6 specifications

6. SPECIFICATIONS

♦ SPECIFICATIONS FOR CIVIL ENGINEERING CONSTRUCTION. ♦ SPECIFICATIONS FOR PIPELINE MATERIALS,

VALVES AND APPURTENANCES FOR WATER LINES.

♦ SPECIAL SPECIFICATIONS FOR TIMBER ♦ SPECIFICATIONS FOR TEMPORARY ROAD

REINSTATEMENT

♦ SPECIFICATIONS FOR CIVIL ENGINEERING CONSTRUCTION

♦ GENERAL SPECIFICATIONS FOR CIVIL ENGINEERING CONSTRUCTION The following specifications published by the Institute for Construction,

Training and Development (ICTAD) shall be used in respect of this contract.

a) Specifications for Building Works (Volume I & II)

b) Specifications for Water Supply, Sewerage and Storm Water Drainage Works

c) Specifications for irrigation and Land Drainage Works

d) Specifications for Electrical and Mechanical works associated with Building and Civil Engineering

Specifications in addition to the above specifications are included in the contract document. Specification included in the Contract Document supersedes the ICTAD specifications. Any specifications which are not covered by the above specifications will be issued by the employer on the request.

♦ SPECIFICATIONS FOR PIPELINE MATERIALS, VALVES AND APPURTENANCES FOR WATER LINES

NWSDB/SBD/Civil-Major : Specifications 6 - 1 CAPC : MPC : DPC : - December 2011 – Version 2

SPECIFICATIONS FOR PIPELINE MATERIALS, VALVES AND

APPURTENANCES

TABLE OF CONTENTS

1. GENERAL

1 Ambient Conditions 6 - 7

2 Suitability for Potable Water 6 - 7

3 Definitions 6 - 7

4 Non-metallic Materials 6 - 7

5 Flanges 6 - 7

6 Inspection and Testing 6 - 8

7 Marking of Pipes, Fittings and Specials 6 - 8

8 Protection during Delivery 6 - 10

9 Storing, Handling and Hauling of Pipes, Fittings, Valves and Specials

6 - 10

10 Packing of Bolts, Joint Rings and Gaskets 6 - 10

11 Manufacturer's Certificate 6 - 11

12 Quality and Workmanship 6 - 11

13 Flanged Joint Protection 6 - 11

2. uPVC PIPES AND FITTINGS

1 uPVC Pipes 6 - 12

2 uPVC Fittings 6 - 12

3 Manufacture of uPVC Pipes 6 - 13

4 Jointing of uPVC Pipes and Joint Rings, Sealing Rings and Gaskets

6 - 13

5 Flanges, Nuts and Bolts and Washers 6 - 14

6 Sampling and Testing 6 - 14

7 Acceptance or Rejection of Consignment 6 - 15

8 Saddle straps 6 - 15

9 uPVC couplings

6 - 15


3. POLY ETHYLENE PIPES AND FITTINGS

1. GENERAL 1 Ambient Conditions 6 – 16

2 Suitability for Potable Water 6 – 16

3 Definitions 6 – 16

4 Non-metallic Materials 6 – 16

5 Flanges 6 – 16

6 Inspection and Testing 6 – 17

7 Marking of Pipes, Fittings and Specials 6 – 17

8 Production quality control 6 – 19

9 Protection during Delivery 6 – 19

10 Storing, Handling and Hauling of Pipes, Fittings and Specials 6 – 19

11 Packing of Bolts, Joint Rings and Gaskets 6 – 23

12 Manufacturer's Certificate 6 – 23

13 Quality and Workmanship 6 – 23

4. POLYETHYLEENE PIPES,FITTINGS,SPECIALS AND ACCESSORIES

1 Scope 6 – 25

2 Reference Standards 6 – 25

3 Definitions 6 – 26

4 Materails 6 – 26

5 Dimensions of Pipes & Fittings 6 – 28

6 Method of Manufacture of pipes and Fittings 6 – 28

7 Joint Rings 6 – 30

8 Steel Flange Convertors

6 – 31

9 Gaskets for Flanged Joints 6 – 31

10 Nuts, Bolts and Washers 6 – 32

11 Coatings 6 –32

12 Tolerances

6 – 32

13 Specification for Buttfusion Welding Machine

6 – 33


5. GALVANIZED IRON PIPES AND FITTINGS

1 Standards 6- 34

2 Pipes 6- 34

3 Fittings 6- 34

4 Joints 6- 34

5 Flanges 6- 34

6 Galvanizing 6- 34

7 Protection of Ends 6- 34

6. DI PIPES, FITTINGS, SPECIALS, ACCESSORIES, DI/CI VALVES, MANHOLE COVERS AND SURFACE BOXES- GENERAL SPECIFICATION

1. Ambient Conditions 6 - 36

2. Suitability for Potable Water 6 - 36

3. Definitions 6 - 36 4. Non-metallic Materials 6 - 36 5. Flanges 6 - 36 6. Inspection and Testing 6 - 36

7. Marking of Pipes, Fittings valves and Specials 6 - 37

8. Protection during Delivery 6 - 39

9. Storing handling and hauling of Pipes, Fittings, Valves and Specials

6 - 39

10. Packing of bolts, joint rings and gaskets 6 - 40

11. Manufacturer's Certificate 6 - 40

12. Quality and workmanship 6 - 40

13. Flanged Joint Protection 6 - 40

14. Final Acceptance at site 6 - 40

7. DUCTILE IRON PIPES AND FITTINGS

1. Scope 6 - 42 2. Reference Standards 6 - 42 3. Definitions 6 - 44 4. Classes of Pipes & fittings and Pressure Rating 6 - 44 5. Dimensions of Pipes and Fittings 6 - 44


6. Method of Manufacture of Pipes and Fittings 6 - 45 7. Coating and Lining 6 - 45 8. Socket and spigot joints 6 - 45 9. Joint Rings and Lubricants 6 - 46 10. Flange Joints for pipes and pipeline fittings 6 - 46 11. Gaskets for flanged joints 6 - 47 12. Restrained Self Anchoring Joints 6 - 47 13. Nuts, bolts and washers 6 - 47 14. Polyethylene sleeving for DI pipes and fittings 6 - 48 15. Tolerances 6 - 48 16. Tensile properties of pipes and fittings 6 - 48 17. Hardness of pipes and fittings 6 - 48 18. Works Leak Tightness Test for pipes and fittings 6 - 49

8. DI /CI VALVES, HYDRANTS, SURFACE BOXES AND MANHOLE COVERS - GENERAL SPECIFICATION

1.0 General 6 - 53 1.1 Scope 6 - 53 1.2 Definitions 6 - 53 1.3 Reference Standards 6 - 53

1.4 Records and Drawings for Materials to be supplied 6 - 54

1.5 Materials of Manufacture 6 - 55 1.6 Testing 6 - 55

1.7 Coating 6 - 58

2.0 Types of Valves 6 - 58

2.1 Sluice Valves 6 - 58

2.2 Butterfly valves 6 - 59

2.3 Air Valves 6 - 61

2.4 Check Valves 6 - 66

2.5 Pressure Reducing Valves 6 - 66

2.6 Pressure Sustaining/Relief Valves 6 - 67

2.7 Flow Control Valves 6 - 67


2.8 Altitude Valves 6 - 68

2.9 Ball Float Valves 6 - 68

2.10 Flap Valves 6 - 68

3.0 Extension Spindles, Tee - Keys and Caps 6 - 69

4.0 Fire Hydrants 6 - 69

5.0 Tools 6 - 71

6.0 Surface Boxes 6 - 71

7.0 Manhole Covers and Frames

6 - 71

9. PENSTOCKS 6 – 74

10. FLOW METERS AND WASTE METERS

1 General 6 – 75

2 Differential Pressure Meter 6 – 76

3 Inferential Meters 6 – 76

4 Waste Meters 6 – 77

5 Meters for Service Connections to Domestic, Commercial and Industrial Premises

6 – 77

11.

STEEL PIPES & FITTINGS

1 Standards 6 – 79

2 Grade of Steel used in Pipes and Fittings 6 – 79

3 Welding 6 – 79

4 Manufacturing Process 6 – 79

5 Fittings 6 – 80

6 Pipe Ends 6 – 80

7 Flanges 6 – 81

8 Tolerances 6 – 81

9 Pipe Lengths 6 – 82

10 Inspection and Testing 6 – 82

11 Bitumen (Asphalt) Lining, Coating and Sheathing 6 – 82

12 Preparation of Steel Surfaces 6 – 83

13 Priming 6 – 83


14 Primer under Bitumen (Asphalt) Enamel Coating and Sheathing 6 – 84

15 Enamels 6 – 84

16 Bitumen (Asphalt) Enamel 6 – 84

17 Testing Primers and Enamels 6 – 85

18 Bitumen (Asphalt) Internal Lining 6 – 86

19 Bitumen (Asphalt) Sheathing 6 – 86

20 Sheathing Reinforcement 6 – 87

21 Coating of Fittings 6 – 88

22 Whitewash 6 – 89

23 Pipes to be laid above ground 6 – 89

24 Inspection and Acceptance 6 – 89

25 Mechanical Couplings and Flange Adaptors 6 – 90

26 Marking 6 – 91

27 Protection of Ends 6 – 91

28 Storing Handling and Hauling Pipes and Fittings 6 – 91

29 Protection and Moulding of Couplings 6 – 92

30 Packing of Bolts, Joint Rings and Gaskets 6 – 92

31 Couplings Stools and Pipe saddles 6 – 92

32 Pipes Restraining Bar 6 – 93

33 Cement – Mortar Lining and Coating of Steel Pipes 6 – 93


1. GENERAL 1 Ambient Conditions

All items of materials and equipment shall be in every respect suitable for storage, installation, use and operation in the conditions of temperature and humidity appertaining in Sri Lanka.

The annual average temperature is 32 °C while the relative humidity varies generally

from 70% during the day to 90% at night.

The temperature of potable water to be conveyed in the pipelines will be about 30 deg.C.

2 Suitability for Potable Water

Pipes and pipeline components, including their protective coatings and joint materials, that will or may come into contact with potable water shall not constitute a toxic hazard; shall not support microbial growth; shall not cause taste or odour, cloudiness or discolouration of the water.

3 Definitions

The definitions given in the relevant standards which are referred to in the specification shall apply for the terms used in this specification.

4 Non-metallic Materials

All non-metallic materials supplied shall be listed in the current "Water Fittings and Materials Directory" published by the Water Research Centre, UK, or approved equivalent publication, as a recognized certifying authority having passed full tests of effect on water quality under the requirements for the testing of non-metallic materials for use in contact with potable water.

5 Flanges

All flanges dimensionally shall be in accordance with BS 4504 : Part 3: Section 3.1: 1989 Specification for Steel Flanges - Metric Series. The screw threads in all pipes and fittings shall comply with ISO Metric Screw Threads.


6 Inspection and Testing

The Contractor shall supply, furnish and prepare the necessary test pieces and samples of all materials and supply the labour facilities and appliances for such testing as may be required to be carried out on his premises according to this specification. If there are no facilities at his own works for making the prescribed tests the Contractor shall bear the cost of carrying out the tests elsewhere.

The Engineer or nominated Inspection authority shall have full access to all parts of the plant that are concerned with the testing, furnishing or preparation of materials for the performance and testing of work under this Specification.

The Contractor shall furnish the Engineer with reasonable facilities and space (without charge) for the inspection, testing and obtaining of such information, as he desires regarding the character of material in use and the progress and manner of the work.

Further all valves shall be tested to the appropriate test pressure at the manufacturer’s

works and shall be supported by a test certificate from the manufacturer. The format for test certificate shall be in accordance with the format given in the

schedule of particulars. 7 Marking of Pipes, Fittings, Valves and Specials All markings described below shall be legible and durable unless otherwise specified. All pipes and fittings shall be marked with the information specified in clause 4.6 of

BS EN 545 : 1995. The mark of the manufacturer shall be embossed on all pipes and fittings other markings may be cast on, cold stamped or painted with an indelible paint.

The Sluice valves, Butterfly valves, Check valves and Hydrants shall be marked in

complying with the relevant provisions of BS 5163 : 1986, BS 5155 : 1984, BS 5153 : 1991, BS 750 : 1984 respectively.

All other valves which are not mentioned above but covered under this specifications

shall be marked with at least nominal size, manufacturer’s name (or trade mark), directions of closing, body material designation.

The manhole covers and surface boxes shall be marked in complying with clause 9 of

BS EN 124 : 1994. In addition to what is specified above the additional markings and the lettering sizes

shall be made with details as per the table 1 hereof.


Table 1 Item Diameter (mm) Details required Lettering Heights

Details (mm) Pipes

above 350

"NWSDB"; Pipe standard (BS EN or other); Class or type ; Nominal dia. (at intervals not more than 3 m)

50

150 to 350 (both inclusive)

as above 25

50 to 150

as above 10

Fittings and Specials

above 350

"NWSDB"; Pipe standard (BS EN or other; Class or type ; Nominal dia.

25

150 to 350

as above (except “NWSDB”) 10

as above (“NWSDB”) 25

150 to 350

as above 10

Manhole Covers

All sizes “NWSDB"; "WATER" or "SEWAGE" (whichever is applicable); Standard (BS EN or other); Class or type ; Size of clear opening.

50

Surface Boxes

All sizes

As for manhole covers 20

Valves All sizes

Weight of valve As appropriate

The Contractor shall label and clearly mark all crates and boxes in indelible paint as specified in the notes forming a part of this Specification.

In addition, all fittings shall be marked with the corresponding item number in the Bill of Quantities or other number specified by the Engineer.


8 Protection during Delivery

The Contractor shall provide protection, to the approval of the Engineer, for the ends of all pipes and fittings prior to the pipes and fittings leaving the place of manufacture and shall maintain such protection until the items reach their destination in order to guard effectively against damage during transit and storage and the ingress of foreign matter inside the pipes and fittings.

All valves and fittings shall be securely packed in crates and boxes to prevent damage

during delivery. The cost of packing shall be deemed to be included in the Contract Rates and crates will not be returned.

All details of the proposed method of providing such protection shall be submitted at the time of tendering. The cost of providing protection to the ends of pipes and fittings shall be included in the unit prices tendered in the Bills of quantities.


All materials shall be stored in an approved location and in such a manner as to preserve their quality and condition. Storage shall be in accordance with the manufacturer’s recommendation. Materials and components shall be handled in such a manner as to avoid any damage or contamination and in accordance with all applicable recommendations of the manufacturers. The Contractor shall give instructions to the shipper on precautions to be taken in the handling of the pipes, valves and other components during loading, towage and unloading, and shall give particulars of these instructions to the purchaser. Also particular attention shall be paid when handling pipes and fittings, to avoid damages to external and internal coatings.

10 Packing of Bolts, Joint Rings and Gaskets

Bolts of the same length and size (and their accompanying nuts and washers) shall be packed together in boxes not exceeding 100 kg. gross weight.

Joint rings and gaskets shall be packed in boxes and separate packages shall be provided for each size and description of ring or gasket.


Each box and package therein shall be clearly labelled stating the number, size and description of the contents.

11 Manufacturer's Certificate

The Contractor shall supply to the Engineer a certificate stating that each item supplied has been subjected to the tests laid down herein and conforms in all respects to this Specification or such other Specification which has been submitted to and approved by the Engineer.

12 Quality and Workmanship

All pipes, fittings, accessories, valves, hydrants, surface boxes, and manhole covers shall be manufactured in compliance with the ISO 9001 quality system standards. Quality assurance certification should be from an organisation accredited to issue such certification and the manufacturer shall have this certification valid during the supply and delivery of the materials. Document evidence regarding accreditation together with the scope of certification should be provided.

13 Flanged Joint Protection

All flanged pipes and sluice valves shall be supplied with complete ‘Corrosion’ protection materials in accordance with the manufacturer’s recommendation. The complete joint protection includes the materials, namely profiling mastic or primer, paste, tape and PVC or Polyethylene outer wrapping. The quantity of materials required for each diameter joint shall be calculated in accordance with the manufacturer to cover the whole joint including nuts and bolts. The supplier shall provide the required details of quantities in the schedule of particulars.

14. Final Acceptance at Site

All pipes, fittings, valves & accessories shall conform to the specification at site. Engineer shall carryout necessary inspection at site prior to final acceptance.

NWSDB/SBD/Civil-Major : Specifications 6 - 12 CAPC : MPC: DPC :- December 2011 – Version 2

2. uPVC PIPES AND FITTINGS

1 uPVC Pipes Socket and Spigot uPVC pipes shall be of the type specified, comply with Sri Lanka

Standards 147 : 1993 together with additional clauses set out in this Specification. The pipes shall bear the SLS marking as well as markings as per clause 7 under General of this Specification herein and shall be supplied in lengths not exceeding 6 meters.

2 uPVC Fittings uPVC fittings shall be injection moulded except for bends and repair sockets which shall either be injection moulded or formed from pipe complying with SLS 147: 1993 and shall be compatible with the uPVC pipes offered. Solvent welded fittings shall comply with SLS 659 Part 1: 1993 and/or BS 4346 Part 1: 1969 together with additional clauses set out in this Specification. In case of mechanical jointed fittings, the fitting shall comply with either BS/ISO or other international standard which is acceptable to the Engineer as providing better quality of materials and workmanship than specified above, together with additional clauses set out herein.

The fittings and specials, if imported shall be accepted subject to the temperature correction in accordance with Table 1 below, which requires higher class fittings than that specified for supply, and shall be from manufacturers having quality assurance system ISO 9002 in operation.

Table 1 : Temperature Correction

Type of Fittings Specified in BOQ Type/Class of Fittings to be Supplied, as per BS 3505 : 1986 if imported

Type 600 Type 1000

Class C (9.0 bar) Class D (12.0 bar)

Note: The SLS 147 has classified the uPVC pipes according to the maximum working

pressure at 29°C while BS 3505: 1986 classifies uPVC pipes by maximum sustained working pressure at 20°C. Hence, imported fittings, which comply with BS 4346, shall be supplied in conformity with the above table 1 for temperature correction.

Detailed drawings of all fittings and specials shall be submitted by the Contractor to the Engineer for his approval prior to the commencement of manufacture.

The Contractor shall be responsible for the compatibility of fittings with the uPVC

pipes offered; and satisfy the hydrostatic pressure requirements as set out in clause 5 of BS 4346 : Part 2 : 1970.


3 Manufacture of uPVC Pipes The Contractor shall furnish copies of certificates of quality control tests carried out

during manufacture of the pipes and fittings in accordance with section 8.4 of SLS 147 and shall if required by the Engineer undertake such additional tests as he considers necessary.

The Contractor shall, when required, disclose to the Engineer particulars of all toxic

substances present as the result of tests carried out by the methods described in section 7.2 of SLS 147.

4 Jointing of uPVC Pipes and Joint Rings, Sealing Rings and Gaskets uPVC pipes of diameters 90 mm and above shall be jointed by means of mechanical

joints with joint rings, in accordance with BS 4346: Part 2: 1970 (with latest amendments) Solvent cement joints are only acceptable for pipes of lesser diameters.

All rubber joint rings, rubber sealing rings, rubber gaskets requiring for jointing uPVC socket and spigot pipes and specials and flanged pipes and specials shall conform to BS 2494 : 1990, Type W (Potable Water Application) in Table 3. The Solvent cement shall comply with BS 4346 : Part 3 : 1982 or SLS 935 : 1991. The joint rings, sealing ring and gasket material shall be EPDM/SBR. The hardness range of the material for joint rings and sealing rings shall be 50-60 IRHD and the hardness range of the material for gaskets shall be 70-80 IRHD. All gaskets shall be of the inside bolt circle type. Lubricant proposed for jointing mechanical joints of uPVC pipe shall not impart any taste, affect the quality of the water or be conducive to the growth of organisms. The Contractor shall provide certificates to the effect that rubber joint rings, rubber sealing rings, rubber gaskets provided under this Contract have been designed and manufactured considering the following aspects so as not to render leaky joints at pressures not less than 15 bars when in use. i. cross sectional dimensions

ii. peripheral length

iii. smooth surface finish without any blemishes, depressions, protrusions etc.

iv. gaskets shall be moulded type without any joints.

The Contractor shall provide written instructions on the method of forming the chamfer on cut end of pipe for jointing.


5. Flanges, Nuts and Bolts and Washers

uPVC flanges of pipeline fittings shall comply with BS 4504 : Part 3 : Section 3.1 : 1989, and BS EN 1092 : Part 2 : 1997 for PN 10 or PN 16 nominal pressure rating whichever is stated in the Bill of Quantities.

The flanges shall be of raised faced type. All nuts washers and bolts to be supplied with flanges shall be of high tensile steel complying with BS 4395 parts 1 and 2: 1969. The screw threads in all pipes and fittings shall comply with ISO metric screw threads. The bolt lengths shall be sufficient to ensure that nuts are full threaded when tightened in their final position with two threads showing. Washers shall be provided under the head of the bolt and under the nut.

6 Sampling and Testing The number of samples to be tested for mechanical characteristics of uPVC pipes shall be selected at random in proportion to the total number of pipes and specials of each diameter in the delivery as follows: For deliveries of lots of 50 to 150 - 2%

For deliveries of lots of 151 to 250 -1% For deliveries of lots of over 250- 0.5%

The Contractor shall, if required, undertake a reasonable number of tests on pipes or specials where the delivery is less than 50 in number. Contractor, on the request of the Engineer, shall arrange the manufacturer to test samples from the production line in the presence of the Engineer or a nominated agency and ensure that the pipes and fittings produced are in conformity with the standards specified in SLS 147 : 1993 and BS 4346 : Part 1 : 1969 and BS 4346 : part 2 : 1970. Hydrostatic test certificates in respect of pipes and fittings manufactured in accordance with, or to a standard not inferior to SLS 147 : 1993 and BS 4346 : Part 1 : 1969 and BS 4346 : Part 2 : 1970 shall be supplied for pipes and fittings separately. The Engineer shall have free access at all reasonable times to those parts of the works engaged on the manufacture and testing of pipes and fittings. If there are no facilities at the works the Contractor shall make arrangements for the prescribed test to be carried out elsewhere without any extra charge to the Purchaser.


7 Acceptance or Rejection of Consignments Any pipe or fitting which fails to satisfy the requirements of the Specification shall be rejected.

However the pipe or fitting which fails to satisfy any of the tests specified in the relative clauses of this specification the test in question shall be repeated on two further samples. Such samples shall be selected from the same pipes lot or from a second selection by agreement between the Contractor and the Engineer and should either of these further samples fail any of the tests, the pipes or fittings represented shall be deemed not to comply with these tests in which the samples failed and the whole lot of such pipes or fittings so represented shall be rejected. One set of "Go/No Go" gauges shall be provided for checking the circularity of each size of uPVC pipes and specials on arrival at their destination.

8. Saddle Straps Straps shall be of uPVC in moulded type for uPVC pipes and be of the bolted type. The bolts and nuts shall be of stainless steel conforming to BS EN ISO 3506-1 : 1998 and BS EN ISO 3506-2 : 1998. Straps for tapping 20 and 25 mm shall be drilled and tapped to the ISO metric pipe thread. All straps shall be proof against leakage after tapping. Full details of the straps should be given in Schedule of Particulars. The "O" ring material shall be of EPDM/SBR and shall conform to BS 2494 : 1990, Type W. Table 3.

9. uPVC Couplings uPVC couplings shall be injection moulded, slip over or similar type suitable for working pressure of 12 bar, unless otherwise specified. Joint rings be of material EPDM conforming to BS 2494 : 1990 type W or of SBR conforming to BS EN 681-1.


3. POLYETHYLENE PIPES AND FITTINGS 1. Ambient Conditions


The annual average temperature is 32 °C while the relative humidity varies generally

from 70% during the day to 90% at night. The PH of water to be conveyed ranges from 6.5 – 7.9.

The temperature of potable water to be conveyed in the pipelines will be about 30 deg. C.

2. Suitability for Potable Water

Pipes and pipeline components, including their protective coatings and joint materials, that will or may come into contact with potable water shall not constitute a toxic hazard; shall not support microbial growth; shall not cause taste or odour, cloudiness or discolouration of the water and shall be approved by recognized certifying authority as being suitable for using portable water supply schemes.

3. Definitions


4. Non-metallic Materials


5. Flanges

All flanges dimensionally shall be in accordance with BS 4504 : Part 3: Section 3.1: 1989 Specification for Steel flanges - Metric Series. The screw threads in the pipes and fittings shall be comply with ISO Metric Screw Threads.

NWSDB/SBD/Civil-Major : Specifications CAPC : MPC: DPC :- December 2011 – Version 2 6 - 17

6. Inspection and Testing

The Contractor shall supply, furnish and prepare the necessary test pieces and samples of all materials and supply the labour facilities and appliances for such testing as may be required to be carried out on his premises according to this specification. If there are no facilities at his own works for making the prescribed tests the Contractor shall bear the cost of carrying out the tests elsewhere. The Engineer or nominated inspection authority shall have full access to all parts of the plant that are concerned with the testing, furnishing or preparation of materials for the performance and testing of work under this Specification.


7. Marking of Pipes, Fittings and Specials All markings described below shall be legible and indelible unless otherwise

specified. All pipes and fittings shall be marked as specified in clause 8 of ISO 4427 : 1996 (E)

and as specified in the Table 1 hereof. The manufacturer’s name Identification mark and the PN rating shall be marked legibly and indelibly on the pipes together with the information shown below..

During the manufacture process, the pipe should be marked with pertinent product

and process information at approximately 1m intervals along the pipe. Specifications require at least the following information to be included.

• Manufacturer's identification or logo, • Standard number (Specification number) e.g. WIS 4-32-13

• The designation of the pipe material (PE 80 or PE 100)

• The dimensions (Nominal outside diameter, nominal wall thickness)

• The outside diameter tolerance (A or B)

• Third party certification mark by the inspection agency approved by the

Engineer.

• The production period (date and code) • The nominal pressure (PN)

The marking should be printed in the following colours:


PE 80 SDR 11 Dark blue

SDR 17.6 Red

PE 100 SDR 11 Black

SDR 17.6 Red

SDR 26 Yellow

SDR 33 Orange

Table 1 - Marking

Item Diameter (mm) Details required Lettering Heights Details (mm)

Pipes Fittings and Specials

above 350


50 to 150

above 350

150 to 350

50 to 150

"NWSDB"; "Water" at intervals not more than 3m as above as above "NWSDB"; "Water" as above as above

50

25

10

25

10(All but NWSDB)

25 for NWSDB

10

The Contractor shall label and clearly mark all crates and boxes legibly and indelibly as specified in the notes forming a part of this Specification.

All fittings shall be marked with the corresponding item number in the Bills of Quantities or any other number specified by the Engineer.

8. Production Quality Control


The manufacturer of PE pipes shall follow quality control tests prescribed in the relevant standards in accordance with BS 5750 part 2 or equivalent. In addition to product quality control tests the manufacturers also must perform and satisfy long term type tests to demonstrate long term performance of pipe as detailed in relevant standards.

9. Protection during Delivery

The Contractor shall provide methodology of protection of pipes and fittings, to the approval of the Engineer and obtain written approval prior to the pipes and fittings leaving the place of manufacture and shall maintain such protection until the items reach their destination in order to guard effectively against damage during handling transit and storage and ingress of foreign matter inside the pipes & fittings.

All fittings shall be securely packed in crates and boxes to prevent damage during delivery. The cost of packing shall be deemed to be included in the Contract Rates and crates will not be returned.

10. Storing, Handling and Hauling of Pipes, Fittings and Specials

All materials shall be stored in an approved location and in such a manner as to preserve their quality and condition as recommended by the manufacturer. Materials and components shall be handled in such a manner as to avoid any damage or contamination and in accordance with all applicable recommendations of the manufacturers recommendations. The Supplier shall provide necessary details to the shipping line on precautions to be taken during loading/unloading handling & transport of the pipes, valves and other components, in the sea. Supplier shall provide to the purchaser a set of recommendations of manufacturer for handling, loading, unloading, transporting and storing of polyethylene pipes and fittings.

General Principles

The recommendations for handling and storage are the same for both PE 80 and PE 100 pipes although due to their increased stiffness, even greater care may be required in the handling of PE 100 pipe coils than PE 80 pipes of similar wall thickness.

Polyethylene is a tough resilient material which is relatively light and easy to handle although it is prone to damage through scoring by sharp objects. Therefore careful handling is always required and the dragging of straight pipe and coils should be avoided whenever possible. The maximum allowable depth of scoring of the external surface of the pipe is 10% of the wall thickness. Pipes and fittings showing obvious defects or excessive scoring should be withdrawn, clearly identified as unsuitable and, where appropriate, returned to the source of supply.


The general properties of polyethylene are unaffected by low ambient temperatures but, having very smooth surfaces, the pipes and fittings become slippery in wet or frosty weather. Particular attention should be given to effective securing and storage under such conditions. Extra care should also be taken when handling large diameter prefabricated fittings during very cold weather.

The packaging of pipes by the manufacturer is normally consistent with the requirement to prevent damage and to comply with safety considerations. Usually pipes are delivered strapped into convenient bundles or banded coils. Fittings are normally supplied in separate bags or cartons together with any associated small items, such as bolts and gaskets.

As far as practicable the protective packaging (pallets, strapping, bags etc.) should be kept intact until the material is required for use. The temporary capping or plugging of pipe ends is recommended.

Pipes and fittings likely to be stored outside for periods longer than 12 months should be covered by a tarpaulin or black polyethylene sheeting to prevent ultra violet degradation from sunlight. Electro fusion fittings should be stored under cover and in their protective packaging. For hygiene purposes, the pipe ends must be protected from the ingress of dirt/water etc. This protection should be carefully disposed of following use.

Transport and Delivery

For transporting bulk loads, vehicles should be provided with a clean flat bed, free from nails or other projections, which may cause damage. If high sided lorries are used, special care must be taken to prevent slippage or excessive bowing of the pipes and extra protection given at all sharp edges. Care should be taken to avoid positioning pipes and fittings near or adjacent to exhaust systems or other heat sources and to avoid possible contamination from materials such as diesel oil.

Metal chains or slings should not be brought into direct contact with the material. Webbed slings of polypropylene or nylon are recommended. Straight pipes should be fully supported and bound together. Pipes must not rest on the integral socket, if one is incorporated.

When transporting 'pupped' fittings, these should not be loaded in a way that could distort the pup end.

Both vertical and horizontal deliveries of coiled pipes are permissible, although in the case of horizontal transportation special notification may be required for highway authorities in respect of wide load regulations.

Following the quality control inspection and testing, caps or plugs are to be provided to protect the jointing surfaces during transportation and storage. The finished and


protected pipes are then carefully packed into manageable units (bundles or coils) prepared for shipments.

Off Loading

Bundled Pipes

When lifting by crane, non metallic wide band slings or ropes should be used, and for pipe lengths greater than 6m, load spreading beams of a length at least equivalent to one quarter of the length of the pipe or bundle pack should be employed.

Chains or end hooks should not be used. Care should be taken to avoid damage to pipes and pipe ends during lifting, particularly those pipes with couplers.

Some bending should be allowed for in the middle of the lift when loading and unloading pipes and, because of this, lifting points should always be well spread and evenly spaced.

Standard bundle packs, 6m long, may be handled by fork lift trucks but due allowance should be made for the flexible nature of the pipes in the positioning of the forks and the raising of the load.

Bundle packs greater than 6m long should be handled either by a side loader with a minimum of four supporting forks, or by a crane using a spreader beam and suitable slings. Individual pipes may be and led in the same way. Off-loading on site may be made easier by using skid timbers and rope slings.

Coiled Pipes

Reinforced adhesive tape at least 50 mm wide should be used for banding. Complete coils are secured by outer and intermediate bands and individual layers are also independently secured. These should not be removed until the pipe is required for actual use.

Pipe sized > 63 mm should be moved and uncoiled using and approved dispensing trailer.

Before unstrapping pipe form the coil or drum, both pipe ends must be firmly mechanically restrained. The band securing the outer end of the pipe should be removed first and the movement of the free end carefully controlled. This removal should be followed with those securing successive layers. No more bands should be removed than necessary to release the length of pipe immediately required. After sufficient pipe has been cut from the coil the protective end cap must be replaced on the remainder. The outer end of the pipe should be suitably re-marked as such.

When removed form the coil or drum, the pipe will be oval and curved. The extent of ovality and curvature will depend upon the temperature, SDR rating, pipe diameter, coil diameter and material type. Although both ovality and curvature will reduce naturally with time, special hardware is available to facilitate handling and jointing.


Fittings

Hooks should not be used to lift fittings which are generally supplied in cardboard boxes or polyethylene bags.

Storage at Depot

All materials should be carefully inspected at the time of delivery and any defective material set aside before accepting the delivery into stores. Any such defects should be notified to the supply source immediately.

Materials of different polymer manufacture should be kept separately and clearly identified. Blue polyethylene pipe should preferably be stored under cover and protected from direct sunlight until required for use. Where storage facilities necessitate the material to be exposed externally , suitable opaque protective sheeting should be used.

All pipe stacks should be made on sufficiently firm, flat ground to support the weight of the pipes and any necessary lifting equipment. Stacking heights should be kept to a minimum and adequate space allocated for lifting machinery to manoeuvre without causing accidental damage.

For safety and the convenience of handling, the stacking height for bundles should not be more than 3 metres. To prevent possible deformation of the pipes, bundles must be stored timber to timber.

For similar reasons, pipe coils should be stored flat and the number of coils per stack should be limited to;

• 7 coils for 20 mm diameter pipe






• 1 coil for 110 mm diameter pipe



Where individual pipe lengths are stacked in pyramidal fashion, deformation may occur in the lower layers, particularly in warm weather. Such stacks should therefore be no more than 1 metre high. Socketed pipes should be stacked with the sockets at


alternate ends and with the sockets protruding to avoid uneven stacking which may permanently distort the pipes. Polyethylene fittings should be stored under cover, preferably on racking and in the manufacturer’s protective wrapping or cartons which should be kept intact until the fitting is required for use.

At all times pipes and fittings should be stored away from exhaust outlets and all other high temperature sources. Care should also be taken to avoid contact with lubricating or hydraulic oils, gasoline, solvents and other aggressive chemicals.

All special tools and equipment associated with the jointing of PE pipes and fittings should be stored separately and securely until they are required for use. The heating faces of fusion tools should be kept in a position where the surfaces are protected from scratching or other damage. Tools incorporating cutting edges should likewise be protected from damage that could cause poor joint preparation.

11. Packing of Bolts, Joint Rings and Gaskets


Joint rings and gaskets shall be packed in boxes and separate packages shall be provided for each size and description of ring or gasket. Each box and package therein shall be clearly labeled stating the number, size and description of the contents.

12. Manufacturer's Certificate


13. Quality and Workmanship All pipes, fittings, accessories, valves, hydrants, surface boxes, and manhole covers shall be manufactured in compliance with the ISO 9001 quality system standards. Quality assurance certification should be from an organization accredited to issue such certification and the manufacturer shall have this certification valid during the supply and delivery of the materials. Document evidence regarding accreditation together with the scope of certification should be provided.


4. POLYETHYLENE PIPES, FITTINGS, SPECIALS AND ACCESSORIES

1. Scope

This specification covers polyethylene pipes and associated fittings for the use of cold drinking water.

2 Reference Standards ISO 4427 Polyethylene (PE) pipes for water supply

specifications.

EN12201-1 Plastic piping System for Water Supply –Polyethylene

(PE) Part 1- General

EN12201-2 Part 2- Pipes

EN12201-3 Part 3- Fittings

EN12201-4 Part 4- Valves

EN12201-5 Part 5- Fitness for purpose of the system

BS 2782-11 Thermoplastics pipes for the conveyance of fluids

Method 1121B:1997 Nominal outside diameters and nominal pressures –

Metric series.

BS ISO 4065:1996 Thermoplastic pipes universal wall thickness table.

BS ISO 11922-1:1997 Thermoplastic pipe for conveyance of fluids -

Dimensions and tolerances.

WIS 4-24-01 Specification for mechanical fittings and joints

including flanges for polyethylene pipes for the

conveyance of cold potable water for tee. Size range 90-

1000 inclusive made to metal or plastics or a

combination of both.

WIS-4-32-03-1987 Specification for blue polyethylene pressure pipe for

cold potable water (nominal sizes 90-1000 for

underground or protected use).

WIS-4-32-08 issue 2-1994 Specification for site fusion of PE 80 and PE 100 pipe

& fittings .


WIS 4-32-13-1993 Specification for blue higher performance polyethylene

(HD PE/PE 100) pressure pipes (nominal sizes 90-

1000) for underground or protected use for the

conveyance of water intended for human consumption.

WIS 4-32-15-1995 Specification for PE 80 and PE 100 spigot fittings and

for drawn bends nominal sizes up to and including 1000

mm.

DIN 8075-1999 Polyethylene (PE)pipes General Quality Requirements

and Testing .

DIN 8074-1999 Polyethylene (PE) Pipes-dimension

ISO 12162:1995 Thermoplastics material for pipes and fittings for

pressure applications- clarifications- clarification and

designation overall service (design-co-efficient).

DIN 16963 1-15 series Pipes joints and elements for high Density Polyethylene (HDPE) pressure pipe lines.

BS6572:1985 Specification for blue polyethylene pipes up to nominal

size 63 for below ground use for portable water. WIS-4-32-12-1995 Specification for PE80 and PE100 electrofusion fittings

for nominal sizes up to and including 630mm. BS 2494 : 1990 Material for Electromeric joint rings in pipe work and

pipe lines. 3. Definitions

The definitions given in the relevant standards which are referred to in the specification, shall apply for the terms used in this specification.

4. Materials

4.1 Pipes

4.1.1 Polyethylene Pipes Polyethylene pipes shall be flexible and in pipe form or coil form complying with standards given in the reference standards in the document. Pipes shall be manufactured by using polyethylene as main raw material. During the manufacturing process.


4.2 Fittings

Polyethylene fittings shall be manufactured by injection moulding , factory welding or formed in the factory complying with the standards referred in the document.

Fittings shall be suitable either for electro fusion or but welding as specified in the Bill of quantities.

In addition to the information given in clause 7 of General Specifications following information to be marked on the fitting.

• In case of a bend, bending angle and incase of unequal tee branch line

size and main line size.

• Pressure rating at relevant temperature

• Standard dimension ratio (SDR)

• Fusion time (Seconds)

• Cooling time (minutes)

• System voltage 4.3 Compression Fittings for PE pipes

Couplings, flange adaptors etc shall be compatible with the pipes specified in item 4.1.1. hereof;

4.4. Testing

Testing shall be carried out fully in accordance with the requirements of ISO 4427

and DIN 8075- 1999 or equivalent standard acceptable to the purchaser 5 Dimensions of Pipes and Fittings Dimension of standard pipes shall conform to the following standards. ISO 4427 - PE pipes for water supply specifications BS 2782 - for outside diameter & nominal pressures II: methods II 21B 1997 ISO 161-1 BS ISO 4065 – 1996 - Thermoplastic pipes – universal wall thickness table


ISO 11922 – 1:1997 - Thermoplastic pipes for the conveyance of fluid- Dimensions & tolerances – Part I metric series

DIN 8074 - Polyethylene pipes dimensions August 1999

Dimensions of fittings shall conform to the following standards. WIS – 4 – 32 – 15 - Specifications for PE 80 and PE 100 Spigot

fittings and drawn 1995 bends for nominal sizes up to and including 1000mm

DIN 16963 1-15 series Pipes joints and elements for high Density

Polyethylene (HDPE) pressure pipe lines. Standard lengths of a straight pipe shall be 12 m.

6. Method of manufacturing of pipes & fittings

6.1 Manufacturing of PE Pipes and Fittings 6.1.1 Polyethylene are manufactured by various processes and are blended with anti-

oxidants, pigments and UV stabilizers to ensure the material is suitable for use in the water industry. Amongst other factors, the range and quantities of co-monomers used can result in substantially different basic properties, e.g. melt flow rate, density, creep resistance etc.

The resulting compound is normally delivered to the manufacture in the form of granules and the PE pipes are produced by an extrusion process.

The bidder shall submit full details of manufacturing process that he intended to use with the bid.

6.1.2 The manufacture of PE Pipe is a continuous processing which necessitates strict and accurate control of both materials and plant to achieve the required quality.

6.2 Production Quality Control 6.2.1 The manufacture of PE pipe is a continuous processing which necessitates strict and

accurate control of both materials and plant to achieve the required quality. A range of quality control tests pressures in the relevant standards should be applied within the scope of a quality assurance in accordance with BS 5750: Part II.

6.2.2 These control procedures shall include:

• quality testing of raw materials, i.e. base compound. • Checks on the uniformity and consistency of the granules


• control of processing parameters in terms of temperature, pressure, flow rates, haul off speed and energy input

• visual inspection of the pipes to check general appearance, dimensional

compliance and any indication of inclusions or processing flaws in pipe barrels and jointing ends,

• production short term tests, to identify any variations in the plant function.

6.2.3 Essential short-term quality control tests and procedures are described in the relevant

Water Industry Specifications include the following

• appearance and surface condition • dimensions

• thermal stability

• elongation at break

• hydrostatic pressure test at 800 C

• short term pressure test

6.3 Product Type Tests 6.3.1 In addition to 'production quality control' tests, there are a number of important

longer-term "Type Tests' that must be undertaken to demonstrate the long-term performance of the pipe. These tests are also required whenever there is any change in such parameters as formulation, size, classification or processing technique.

6.3.2 These 'Type Tests' are again detailed in the relevant specifications and include the

following:

• effect on water quality • resistance to weathering

• long term hydrostatic pressure testing

• resistance to fracture on impact tensile strength,

• elongation and weld test

6.3.3 Perhaps the most fundamental Type Test is the long term hydrostatic test which is a

standard means of predicting the long-term performance of the pipe. In this test, samples are subjected different circumferential (hoop) stresses by pressurization and the subsequent time to pressure is recorded. The individual results are plotted as a log stress versus log time graph. They are then subjected to regression analysis to obtain an extrapolated 50 year stress level.


6.3.4 It is worth bearing in mind that the above requirements for long-term performance

levels are minimum values and manufacturers usually ensure that their products can comfortably meet these standards, i.e. the pipes have an additional factor of safety built into them to cover any manufacturing variables.

6.4 Classification 6.4.1 The terms PE 80 and PE 100 are a classification developed in line with a decision

taken at CEN/TC 155, the European Technical Committee drafting plastics piping system standards for polyethylene products for water supply.

6.4.2 According to this classification, as detailed in ISO/DIN 12162, PE 80 material has a

Minimum Required Strength (MRS) value of 8 Mpa and PE 100 has a MRS value of 10 Mpa. The international Standards Organisation (ISO) technical procedure ISO TR 9080 (3) identifies these MRS values derived from the 50 year extrapolated 97.5% Lower Confidence Limit (LCL) failure stress.

7. Joint Rings

The physical properties of elastomeric joint rings shall comply with Table 3 of BS 2494: 1990. The joint rings shall also comply with the relevant provisions in BS 2494 for effects on water quality and resistance to microbiological deterioration. The material of joint rings shall be of EPDM/SBR and shall be dual hardness punching type with 76-84 IRHD at the heel of the ring and 46-55 IRHD at the bulb of the ring. Joint rings shall be supplied by the pipe manufacturer. Each joint ring shall be marked clearly and durably in accordance with the following information in a manner that does not interfere with the sealing function of the ring, in complying with clause 3.9 of BS 2494: 1990

a) The nominal size b) Manufacturer’s identification

c) The number of the BS or BSEN with seal type designation

d) Abbreviation for the elastomer

Flange Joints for Pipes and Pipeline Fittings

Flanges for pipes and pipeline fittings shall unless otherwise stated comply with BS 4504: section 3.1: 1989 and BSEN 1092: Part 2: 1997. Flanges shall be of PN16 nominal pressure rating and shall be raised faced, unless otherwise stated. Flanges in accordance with BSEN 545 and ISO 2531 are dimensionally compatible with BS 4504: Section 3.1. Flanged joints shall be complete with all nuts, bolts, gaskets and two washers per bolt.


The flanges of all fittings shall be integrally cast. The flanges of flanged pipes shall either be integrally cast or screwed or factory welded unless otherwise stated. ‘Factory welded’ means that the flanges are welded to the pipes at the point of manufacture under factory conditions with inspection agency certification. The Contractor shall be responsible for checking and ensuring that mating flanges are compatible in all cases, including where connections are required to pipe work and valves associated with pumping plant and inlet/outlet pipe work at service reservoirs or other structures.

8. Steel Flange Converter

Steel Flange Converter shall be made out of polyethylene and shall be conform to the WIS 4-24-01 specification for mechanical fittings and joints including flanges for polyethylene pipes for conveyance of cold portable water for the size range 90-1000 inclusive made of metal or plastics or a combination of both.

9. Gaskets for Flanged Joints

Gaskets for flanged pipe joints shall be of the inside bolt circle type and the dimensions shall comply with BS 4865: Part 1. The physical properties of gaskets shall comply with Table 3 of BS 2494: 1990. The Gaskets shall also comply with the relevant provisions in BS 2494 for effects on water quality and resistance to microbiological deterioration. The Gasket material shall be EPDM/SBR and shall be of average hardness of 76-84. The Gaskets shall be supplied by the manufacturer and shall suit for PN 16 flanges unless otherwise stated. Each gasket shall be marked clearly and durably in accordance with the following information in a manner that does not interfere with the sealing function of the gasket, in complying with clause 3.9 of BS 2494: 1990. a). The nominal size b). Manufacturers identification c). The number of the BS or BSEN with seal type designation. d). Abbreviation for the elastometre

10. Nuts, Bolts and Washers

The nuts, bolts and washers for flanged joints shall be of high tensile steel and shall comply with BS4395: Part 1 and 2: 1969.


The bolting shall comply with the relevant provisions of BS 4504: Section 3.1:1989. The Bolt lengths shall be sufficient to ensure that nuts are full threaded when tightened in their final position with two threads showing. Two washers per each bolt shall be supplied for providing under the head of the bolt and under the nut.

11. Coating

All steel flanges shall be protected against corrosion. The protection shall comprise a coating of metallic zinc or zinc rich. Paint complying with ISO 8179:1985 followed by two coats of bituminous based black paint complying with BS 3416. Type II or an approved coat of epoxy. Coating shall apply under factory conditions in complying with BSEN 545:1995 or ISO 4179:1985/!SO 6600:1980.

12. Tolerances

Tolerances on wall thickness & weight, and length shall be in accordance with BS

ISO 11922 - 1: 1997 or DIN 8074 1999 or ISO 4427 The tolerances on flange thickness and flange diameter shall be in accordance with

BS4504: section 3.1:1989. The tolerances on flange thickness, flange diameter and bolt holes in polyethylene . Steel flange converters to be used of connecting different type of material shall conform to BS 4504:1989.


13. Specification for Butt Fusion Welding Machine

I. Machine shall be hydraulically operated and suitable for welding of PE pipes. II. Machine shall consist of self –aligning frame and compact dimensions, to be

suitable for working on narrow roads.

III. Machine shall be comprised of four clamps in lightweight alloy of which the third one is easily adjustable in order to weld special pieces, and the automatic disconnecting devices to detach the pipes the heating mirror at the end of heating time.

IV. Heating mirror shall be silver stone coated with electronic thermostat and separate

thermometer in order to continuously check the temperature of the heating mirror. Operating electricity requirement of the heating mirror shall be 230V 50Hz.

Also it shall include removable electric facing tool complete with reducing gear, double cutting edged blades, safety micro switch all which allow the engine to start only in operating position.

i. An electrically operated mechanical block device avoiding dislocation during the facing operation. Operating electricity requirement shall be 230V, 50Hz.

ii. A support for facing tool and heating mirror suitable to carry the two part and to

hold them when it is not in use.

iii. Hydraulic double throw pump with precision pressure gauge (class 1.0-100 bar scale and 100mm face to easy reading) incorporates a device which maintains pre-set line pressure even when motor is not running. Allows continuous pressure adjustments and features flexible hoses with quick disconnect dry-lock couplings. Mounted in a tough protective frame, with two transport handles. Operating electricity requirement is 230V 50Hz.

iv. Light weight aluminium reducing inserts (8 inserts per set including 6 inserts for

pipes and 2 inserts for fittings) sizes 200,225,250,280,315,355,400,450mm.

v. Upper fitting clamp 500mm for short fittings.

vi. Stub end device with size range 200 to 500 mm. vii. A Generator of adequate capacity. viii. A 2 year warranty to cover all the equipments offered.

NWSDB/SBD/Civil-Major : Specifications CAPC : MPC: DPC :- December 2011 – Version 2

6-34

5. GALVANIZED IRON PIPES AND FITTINGS 1. Standards Pipes, bends and similar fittings shall comply with BS 1387 : 1985 or ANSI/ASTM A

120 - 79 together with additional clauses and conditions set out in the Bills of Quantities or any other National Standards or Specifications acceptable to the Engineer.

2. Pipes The pipes shall be of heavy quality and conform to the requirements of Table 5 of BS

1387 : 1985. 3. Fittings The dimensions of fittings shall be as indicated in the Bills of Quantities. Where no

dimensions are given, they shall be at the option of the manufacturer and to the approval of the Engineer. The fittings shall conform to the requirements of BS 1387 : 1985.

4. Joints GI pipes of all diameters shall be joined by GI sockets of suitable strength, conforming

to the requirements of Table 6 of BS 1387 : 1985. 5. Flanges GI screwed flanges shall be suitable for the nominal pressures stated in the Bills of

Quantities as follows: N.P. 10 for a nominal working pressure of 10 kgf/cm2. N.P. 16 for a nominal working pressure of 16 kgf/cm2. Dimensions of flanges shall be in accordance with BS 4504 : 1969 or equivalent

National Standards. 6. Galvanizing Galvanizing shall be carried out in accordance with the requirements of Section 4.3 of

BS 1387 : 1985. 7. Protection of Ends

The threads of all pipes shall be effectively covered with a good quality grease or other suitable compound, and each pipe shall have a protecting ring affixed to the unsocketed screwed end.

NWSDB/SBD/Civil-Major : Specifications CAPC : MPC : DPC - December 2011 – Version 2

6 -35

6. DI PIPES, FITTINGS, SPECIALS, ACCESSORIES, DI/CI VALVES, MANHOLE COVERS AND SURFACE BOXES-

GENERAL SPECIFICATION

TABLE OF CONTENTS

PAGE NUMBER

1 Ambient Conditions 6 - 36

2 Suitability for Potable Water 6 - 36

3 Definitions 6 - 36

4 Non-metallic Materials 6 - 36

5 Flanges 6 - 36

6 Inspection and Testing 6 - 36

7 Marking of Pipes, Fittings valves and Specials 6 - 37

8 Protection during Delivery 6 - 39

9 Storing handling and hauling of Pipes, Fittings, Valves and Specials 6 - 39

10 Packing of bolts, joint rings and gaskets 6 - 40

11 Manufacturer's Certificate 6 - 40

12 Quality and workmanship 6 - 40

13 Flanged Joint Protection 6 - 40

14 Final Acceptance at site 6 - 40


6 -36

GENERAL 1 Ambient Conditions


The annual average temperature is 30 °C while the relative humidity varies generally from 70% during the day to 90% at night.

The temperature of potable water to be conveyed in the pipelines will be about 30 °C.

2 Suitability for Potable Water

Pipes and pipeline components, including their protective coatings and joint materials, that will or may come into contact with potable water shall not constitute a toxic hazard; shall not support microbial growth; shall not cause taste or odour, cloudiness or discolouration of the water.

3 Definitions


4 Non-metallic Materials


5 Flanges

All flanges dimensionally shall be in accordance with BSEN 1092-1 : 2007 Specification for Steel Flanges - Metric Series. The screw threads in all pipes and fittings shall comply with ISO Metric Screw Threads.

6 Inspection and Testing

The Contractor shall supply, furnish and prepare the necessary test pieces and samples of all materials and supply the labour facilities and appliances for such testing as may be required to be carried out on his premises according to this specification. If there are no facilities at his own works for making the prescribed tests the Contractor shall bear the cost of carrying out the tests elsewhere.


6 -37

The Engineer or nominated Inspection authority shall have full access to all parts of the plant that are concerned with the testing, furnishing or preparation of materials for the performance and testing of work under this Specification.


Further all valves shall be tested to the appropriate test pressure at the manufacturer’s works and shall be supported by a test certificate from the manufacturer.

The format for test certificate shall be in accordance with the format given in the

schedule of particulars. 7 Marking of Pipes, Fittings, Valves and Specials

All markings described below shall be legible and durable unless otherwise specified. All pipes and fittings shall be marked with the information specified in clause 4.6 of

BS EN 545 : 2006 . The mark of the manufacturers and class of pipe shall be embossed on all pipes and fittings. Other markings may be cast on, cold stamped or painted with an indelible paint.

The Sluice valves, Butterfly valves, Check valves and Hydrants shall be marked in

complying with the relevant provisions of BS 5163 : 2004, BS EN 1171 : 2002,BSEN 593 : 2004, BSEN 12334 : 2001 , BS 750 : 2006 respectively.

All other valves which are not mentioned above but covered under this specifications

shall be marked with at least nominal size, manufacturer’s name (or trade mark), directions of closing, body material designation.

The manhole covers and surface boxes shall be marked in complying with clause 9 of

BS EN 124:1994.

In addition to what is specified above the additional markings and the lettering sizes shall be made with details as per the table 1 hereof.


6 -38

Table 1 Item Diameter (mm) Details required Lettering Heights

Details (mm) Pipes

above 350

"NWSDB"; Pipe standard (BS EN or other); Class or type ; Nominal dia., Manufacture’s name & Year of manufacture (at intervals not more than 3 m)

50


as above 25

50 to 150

as above 10

Fittings and Specials

above 350

"NWSDB"; Pipe standard (BS EN or other; Class or type ; Nominal dia., Manufacture’s name & year of manufacture, PN (for flanges)

25

150 to 350 (Both inclusive)

as above (except “NWSDB”) 10

“NWSDB” 25

50 to 150

"NWSDB"; Pipe standard (BS EN or other; Class or type ; Nominal dia., Manufacture’s name & year of manufacture, PN (for flanges) Bend angle for bends

10

Manhole Covers

All sizes “NWSDB"; "WATER" or "SEWAGE" (whichever is applicable); Standard (BS EN or other); Class or type ; Size of clear opening.

50

Surface Boxes

All sizes

As for manhole covers 20

Valves All sizes

Weight of valve As appropriate


6 -39

The Contractor shall label and clearly mark all crates and boxes in indelible paint as specified in the notes forming a part of this Specification.

In addition, all fittings shall be marked with the corresponding item number in the Bills of Quantities or other number specified by the Engineer.

8 Protection during Delivery

The Contractor shall provide protection, to the approval of the Engineer, for the ends of all pipes and fittings prior to the pipes and fittings leaving the place of manufacture and shall maintain such protection until the items reach their destination in order to guard effectively against damage during transit and storage and the ingress of foreign matter inside the pipes and fittings.

All valves and fittings shall be securely packed in crates and boxes to prevent damage

during delivery. The cost of packing shall be deemed to be included in the Contract Rates and crates will not be returned.

Each box and package therein shall be clearly labeled stating the number, size and description of the contents.

All details of the proposed method of providing such protection shall be submitted at the time of tendering. The cost of providing protection to the ends of pipes and fittings shall be included in the unit prices tendered in the Bills of quantities.


All materials shall be stored in an approved location and in such a manner as to preserve their quality and condition. Storage shall be in accordance with the manufacturers recommendation. Materials and components shall be handled in such a manner as to avoid any damage or contamination and in accordance with all applicable recommendations of the manufacturers. The Contractor shall give instructions to the shipper on precautions to be taken in the handling of the pipes, valves and other components during loading, towage and unloading, and shall give particulars of these instructions to the purchaser. Also particular attention shall be paid when handling pipes and fittings, to avoid damages to external and internal coatings.


6 -40

10 Packing of Bolts, Joint Rings and Gaskets


Joint rings and gaskets shall be packed in boxes and separate packages shall be provided for each size and description of ring or gasket.

11 Manufacturer's Certificate


12 Quality and Workmanship

All pipes, fittings, accessories, valves, hydrants, surface boxes, and manhole covers shall be manufactured in compliance with the ISO 9001 : 2008 Quality Management System requirements. Quality Management system certificate should be from an organisation accredited to issue such certification and the manufacturer shall have this certificate valid during the supply and delivery of the materials. This certificate shall clearly indicate the location of the place of manufacture of goods.

13 Flanged Joint Protection

All flanged pipes and sluice valves shall be supplied with complete ‘Corrosion’

protection materials in accordance with the manufacturers recommendation. The complete joint protection include the materials, namely profiling mastic or primer, paste, tape and PVC or polyethylene outer wrapping. The quantity of materials required for each diameter joint shall be calculated in accordance with the manufacturer to cover the whole joint including nuts and bolts. The supplier shall provide the required details of quantities in the schedule of particulars.

14 Final Acceptance at site

All pipes, fittings, valves and accessories shall conform to the specification at site. Engineer shall carryout necessary inspections at site prior to final acceptance.


6 -41

7. DUCTILE IRON PIPES AND FITTINGS

TABLE OF CONTENTS PAGE NUMBER

1 Scope 6 - 42 2 Reference Standards 6 - 42 3 Definitions 6 - 44 4 Classes of Pipes & fittings and Pressure Rating 6 - 44 5 Dimensions of Pipes and Fittings 6 - 44 6 Method of Manufacture of Pipes and Fittings 6 - 45 7 Coating and Lining 6 - 45 8 Socket and spigot joints 6 - 45 9 Joint Rings and Lubricants 6 - 46 10 Flange Joints for pipes and pipeline fittings 6 - 46 11 Gaskets for flanged joints 6 - 47 12 Restrained Self Anchoring Joints 6 - 47 13 Nuts, bolts and washers 6 - 47 14 Polyethylene sleeving for DI pipes and fittings 6 - 48 15 Tolerances 6 - 48 16 Tensile properties of pipes and fittings 6 - 48 17 Hardness of pipes and fittings 6 - 48 18 Works Leak Tightness Test for pipes and fittings 6 - 49


6 -42

DUCTILE IRON PIPES AND FITTINGS 1 Scope

This section covers the requirement for the supply of Ductile Iron pipes and fittings. 2 Reference Standards

The following standards are referred to ; ISO 2531 : 1998 Ductile iron pipes, fittings and accessories for pressure pipe lines

BS EN 545 : 2006 Ductile Iron pipes, fittings, accessories and their joints

for water pipelines. Requirements and test methods.

. BS 7874 : 1998 Method of tests for microbiological deterioration of

Elastomeric scales for Joints in pipe work and pipe lines.

BSEN 681 -1 : 1996 Elastomeric seals- material requirement for pipe joint

seals used in water and drainage application. (Vulcanized rubber)

BSEN 681 -2 : 2000 Elastomeric seals- material requirement for pipe joint

seals used in water and drainage application. (Thermoplastic elastomers)

ISO 4633:2002 Rubber seals – Joint rings for water supply drainage and

sewerage pipe lines – specification for materials.

BS 3416 : 1991 Bitumen based coatings for cold application, suitable for use in contact with potable water.

BSEN 10 300 : 2005 Steel tubes & fittings for onshore and offshore pipe

lines. Bitumen hot applied material for external coating. BSEN 1092-1 ;2007 Flanges and their joints. Circular flanges for pipes,

valves, fittings and accessories, PN Designated, steel flanges.

BS 14399 : Part 1 : 2005 Specification for high strength structural bolting

assemblies for pre-loading. General requirements.

BSEN 14399 : Part 2: 2005 Specification for high strength structural bolting assemblies for pre- loading. Suitability test for Pre-loading.


6 -43

BS 1514: Part 1:1997 Dimensions of non-metallic Flanges and their joints.

Dimensions of gaskets for PN designated flanges. Non metallic flat gasket with or without inserts gaskets for pressures up to 64 bar.

BS 4320: 1968 Metal washers for general engineering purposes metric

series. ISO 9001 : 2008 Quality Management System Requirement ISO 4179 : 2005 Ductile iron pipes for pressure and non pressure

pipelines Centrifugal cement mortar lining. ISO 6600 : 1980 Ductile iron pipes centrifugal cement mortar lining

(composition controls for freshly applied mortar). JIS G 5528: 2006 Epoxy powder coating for interior of DI pipes and

fittings ANSI A214 Cement Mortar lining for cast iron and Ductile iron

pipes and fittings for water. ISO 8179 : 2004:Part 1 Metallic Zinc with finishing layer. ISO 8179:1995: Part 2 Zinc rich paint with finishing layer BS EN 12329 : 2003 Corrosion Protection of metals. Electrodeposited

coatings of Zinc with supplementary treatment on Iron or Steel

BS EN 14161 : 2003 Code of practice for Pipe Lines. Pipelines on land :

design, construction and installation. Ductile Iron BS EN 10088: Part 2: 2005 Stainless steel – Technical delivery conditions for

sheet/plate and strip of corrosion resisting steels for general purposes.

BS 6076:1996 Polymeric film for use as a protective sleeving for

buried iron pipes and fittings (for site and factory application)

ISO 8180:2006 Ductile Iron pipes – polyethylene sleeving for site

application. ISO 10804 – 1 : 1996 Restraint Joint System for DI Pipe lines. The year of publication of the standards referred to in the following clauses shall be the year as given above.


6 -44

3 Definitions

The definitions given in the relevant standards which are referred to in the specification, shall apply for the terms used in this specification.

4 Classes of Pipes & fittings and Pressure Ratings

Ductile iron pipes and fittings shall be in accordance with ISO 2531 : 1998 or with BS EN 545:2006. The standard class designation of pipes and fittings shall be as follows unless otherwise stated.

- Socket and Spigot Pipes K 9 - Pipes with Integral Flanges K 12 - Pipes with factory welded flanges K 9 - Pipes with screwed flanges K 9 or K 10 - Fittings except tees K 12 - Tees K 14 - Flanges PN 16

The allowable operating pressures shall comply with Annex A of BS EN 545 : 2006 or ISO 2531 : 1998 unless otherwise stated.

5 Dimensions of Pipes and Fittings

Dimensions of standard pipes and fittings shall be to ISO 2531 or BS EN 545 : 2006 unless otherwise shown on the Drawings or required for special purposes. Where pipes or fittings are required in dimensions other than those specified in ISO 2531 : 1998 or BS EN 545 : 2006, they shall be of the same classes as listed above and shall be designed for the works proof test pressures specified in Table 10 of ISO 2531 or Table 13 of BS EN 545 : 2006 for the relevant nominal diameter.

Manufacturer's product catalogue, showing dimensions, mass and other details of all standard fittings shall be submitted to the Engineer for his approval prior to manufacture.

Manufacturer's detailed drawings of all special fittings shall be submitted to the Engineer for his approval prior to manufacture. Standard pipe lengths shall comply with Table 3 and 4 of BS EN 545 : 2006 for socket and spigot and flanged pipes respectively or Table 2 & 3 of ISO 2531 : 1998 or their latest revision for socket and spigot pipes and flanged pipes unless otherwise stated.


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6 Method of Manufacture of Pipes and Fittings

All straight pipes shall be spun or centrifugally cast and fittings and joint components shall be cast in sand moulds. Prior approval of the Engineer shall be required for any alternative casting methods.

At all stages of manufacture, rigid control shall be exercised and the pipes and fittings shall be sound and free from surface or other defects. Foundries shall comply with the requirements of ISO 9001:2008 Quality Management Systems.

Manufacturing process of Pipes and Fittings shall comply with the ISO 9001: 2008 quality management system requirements and such quality management system possessed by the manufacturer should be from an organisation accredited to issue such certification. Documentary evidence regarding accreditation together with the scope of certification should be provided. Certificate shall clearly indicate the name and address of the location of factory.

The Bidder shall also submit full details of the manufacturing process he intends to use with his tender. Such details shall include but not be confined to;

(1) Casting and heat treatment processes. (2) Cleaning process and preparation of surface of iron before application of coating

and lining. (3) Specification of all lining and coating materials, their thickness and application

procedures.

(4) Ductile Iron Pipes and Fittings shall be from the same manufacturer.

7 Coating and Lining

All ductile iron pipes and fittings shall be protected internally and externally against corrosion. The external protection shall comprise a coating of metallic zinc or zinc rich paint complying with ISO 8179 : Part 1 : 2004 and ISO 8179 Part II followed by two coats of bituminous based black paint complying with BS 3416 : 1991 Type II or an approved coat of epoxy. The internal protection shall be a cement-mortar lining complying with specified thickness in Table 8 of BSEN 545 : 2006 or relevant Table in ISO 4179 : 2005 or ISO 6600 : 1980. All such coatings and linings shall be applied under factory conditions, in complying with BSEN 545 : 2006 or ISO 4179 : 2005/ ISO 6600 : 1980.

8 Socket and Spigot Joints

Standard pipes and fittings for pipelines of ductile iron shall be supplied with push-in socket and spigot joints similar to joint Type A.1 illustrated in BSEN 14161: 2003.


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9. Joint Rings and Lubricants

The physical properties of elastomeric joint rings shall comply with Table 2 of BSEN 681-1 : 1996. The joint rings shall also comply with the relevant provisions in BSEN 681-1 :1996 for effects on water quality and resistance to microbiological deterioration. The material of joint rings shall be of EPDM/SBR and shall be dual hardness punching type with 76-84 IRHD at the heel of the ring and 46-55 IRHD at the bulb of the ring. Joint rings shall be supplied by the pipe manufacturer. Each joint ring shall be marked clearly and durably in accordance with the following information in a manner that does not interfere with the sealing function of the ring, in complying with clause 10 of BSEN 681-1 :1996 a) The nominal size

b) Manufacturer’s identification c) The number of the BS or BS EN or EN with seal type designation. d) Abbreviation for the elastomer

Joint Lubricants for sliding joints have no deleterious effects on either the joint rings or pipes, and be unaffected by the liquid to be conveyed. Lubricants shall not impart to water taste, colour or any effect known to be injurious to health and shall be resistant to bacterial growth.

10 Flanged Joints for Pipes and Pipeline Fittings

Flanges for pipes and pipeline fittings shall unless otherwise stated comply with BS EN 1092 – 1: 2007. Flanges shall be of PN 16 nominal pressure rating and shall be raised faced, unless otherwise stated. Note: Flanges in accordance with BS EN 545 and ISO 2531 are dimensionally

compatible with BSEN 1092-Part 1:2007 Flanged joints shall be complete with all nuts, bolts, gaskets and two washers per bolt. The flanges of all fittings shall be integrally cast. The flanges of flanged pipes shall either be integrally cast or screwed or factory welded unless otherwise stated. ‘Factory welded’ means that the flanges are welded to the pipes at the point of manufacture under factory conditions with inspection agency certification. The Contractor shall be responsible for checking and ensuring that mating flanges are compatible in all cases, including where connections are required to pipe work and valves associated with pumping plant and inlet/outlet pipe work at service reservoirs or other structures.


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11 Gaskets for Flanged Joints

Gaskets for flanged pipe joints shall be of the inside bolt circle type and the dimensions shall comply with BSEN 1514 – Part 1 : 1997. The physical properties of gaskets shall comply with Table 2 of BSEN 681-1:1996. The Gaskets shall also comply with the relevant provisions in BSEN 681-1:1996 for effects on water quality and resistance to microbiological deterioration. The Gasket material shall be EPDM/SBR and shall be of average hardness of 76-84. The Gaskets shall be supplied by the manufacturer and shall suit for PN 16 flanges unless otherwise stated. Each gasket shall be marked clearly and durably in accordance with the following information in a manner that does not interfere with the sealing function of the gasket, in complying with clause 10 of BSEN 681-1:1996. a). The nominal size b). Manufacturer’ s identification c). The number of the BS or BS EN with seal type designation. d). Abbreviation for the elastomer

12. Restrained Self Anchoring Joints

The design of restrained joints shall comply with ISO 10804-1 or equivalent. The joint may be either internally or externally restrained, however in the case of internally restrained joints the locking system and the rubber gaskets shall not be combined together (gasket and the system taking the axial load to be separate pieces).

The spigot of the restrained joint pipes shall be compatible, with or without modification at site, with the standard and restrained joint fittings.

These joints shall be designed by the pipe manufacturer to transmit axial pipe to pipe forces generated due to change in direction of the pipeline and possible pipe line settlement in weak soil areas without thrust blocks. Rubber gasket shall be of neoprene rubber. Locking ring and possible set bolts shall be ductile iron.

13 Nuts, Bolts and Washers

The nuts, bolts and washers for flanged joints shall be of high tensile steel and shall comply with BSEN 14399 – Part II – 2005. The bolting shall comply with the relevant provisions of BSEN 1092- 1: 2007. The Bolt lengths shall be sufficient to ensure that nuts are full threaded when tightened in their final position with two threads showing.


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Two washers per each bolt shall be supplied for providing under the head of the bolt and under the nut.

14 Polyethylene Sleeving for DI pipes & Fittings

Where specified Tubular polyethylene protective sleeving for burried DI pipes & fittings shall comply with the relevant provisions of BS 6076 : 1996 and shall be in accordance with ISO 8180 : 2006. The polyethylene sleeving shall be coloured blue.

15 Tolerances

Tolerances on wall thickness weights and lengths shall be in accordance with BS EN 545 and/or ISO 2531, and the specific references for compliance are as follows.

BS EN 545 : 2006 ISO 2531 : 1998

Wall thickness

Table 8 Table 1

Weights

- Table 3

Lengths Table 6 Table 4 & 5 The tolerances on flange thickness and flange diameter shall be in accordance with

BSEN 1092-1 : 2007. 16 Tensile properties of pipes and fittings

The tensile properties and testing methods shall be in accordance with BS EN 545 or ISO 2531 and the specific references for compliance are as follows:

BS EN 545:2006 ISO 2531 : 1998 Tensile Properties Table 7 Table 6

Test methods Clause 6.3 Clause 4.3.1

Clause 6.3 17 Hardness of Pipes and Fittings

The Hardness of pipes and fittings shall not exceed the following superficial values, when tested in accordance with brinell hardness tests complying with clause 6.4 of BS EN 545 : 2006 or clause 4.3.2. of ISO 2531 : 1998.

Superficial Hardness Pipes

230 HB


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Fittings & accessories 250 HB

18 Works Leak Tightness Test for Pipes and Fittings All pipes and fittings shall comply with works leak tightness requirements of BS EN 545 : 2006 and ISO 2531 : 1998 and the specific references for compliance are as follows: BS EN 545 : 2006 ISO 2531 : 1998 Method of testing Clause 6.5.2 and

Clause 6.5.3

Clause 6.5.2 and 6.5.3

Minimum work test pressures Table 14 Table 10


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MECHANICAL COUPLINGS, REPAIR CLAMPS AND FLANGE ADAPTORS

TABLE OF CONTENTS PAGE NUMBER 1 Mechanical Couplings, Repair clamps and Flange Adaptors 6 - 51


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MECHANICAL COUPLINGS, REPAIR CLAMPS AND FLANGE ADAPTORS

All mechanical couplings, repair clamps and flange adaptors shall comply with ISO 9001:2000 quality Management system requirement . Quality Management system certificate should be from an organisation accredited to issue such certificate. Documentary evidence regarding accredition together with the scope of certification should be provided. This certificate shall indicate the location of the factory. Mechanical couplings and repair clamps shall comply with WIS 4-21-02 or equivalent and shall be PN 16 pressure rated unless otherwise stated. All these fittings shall be protected against corrosions by the application of Polymeric anti-corrosion coatings in accordance with WIS 4-52-01 Class B. (both internal and external) with the coating thickness of not less than 250 microns. Engineer’s approval shall be obtained for any other type of coating, prior to order. The mechanical couplings and repair clamps shall be designed for a safe allowable angular deflection of 6° without leakage while it shall be 3° for flange adaptors. All fastners of couplings, clamps and adaptors shall be electroplated to BS EN 12329 : 2000 grade Zn 10 or equivalent followed by a suitable primer and then with Polymeric anti-corrosion coatings in accordance with WIS 4-52-01 Class B. to a thickness of 60 – 120 microns. Gaskets and rubber rings shall be of EPDM/SBR and the physical properties shall comply with table 2 of BSEN 681-1:1996. Gaskets shall be of the inside bolt circle type and the dimensions shall comply with BSEN 1514 – Part 1 : 1997. The hardness range for Gaskets is 76-84 IRHD. Prior to the commencement of the manufacture the Contractor shall submit to the Engineer, for approval, detailed drawings of all mechanical couplings repair clamps and flange adapters.


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8. DI /CI VALVES, HYDRANTS, SURFACE BOXES AND MANHOLE COVERS - GENERAL SPECIFICATION

TABLE OF CONTENTS

PAGE NUMBER 1.0 General

1.1 Scope 6 - 53

1.2 Definitions 6 - 53

1.3 Reference Standards 6 - 53

1.4 Records and Drawings for Materials to be supplied 6 - 54

1.5 Materials of Manufacture 6 - 55

1.6 Testing 6 - 55

1.7 Coating 6 - 58 2.0 Types of Valves

2.1 Sluice Valves 6 - 58

2.2 Butterfly valves 6 - 59

2.3 Air Valves 6 - 61

2.4 Check Valves 6 - 66

2.5 Pressure Reducing Valves 6 - 66

2.6 Pressure Sustaining/Relief Valves 6 - 67

2.7 Flow Control Valves 6 - 67

2.8 Altitude Valves 6 - 68

2.9 Ball Float Valves 6 - 68

2.10 Flap Valves 6 - 68 3.0 Extension Spindles, Tee - Keys and Caps 6 - 69 40 Fire Hydrants 6 - 69 5.0 Tools 6 - 71 6.0 Surface Boxes 6 - 71 7.0 Manhole Covers and Frames 6 - 71 Annex D1 - General components of the single orifice Air Valve 6 - 72 Annex D2 - General components of the double orifice Air Valve 6 - 73


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DI/CI VALVES, HYDRANTS, SURFACE BOXES, MANHOLE COVERS 1.0 General 1.1 Scope

This section covers the requirements for the supply of valves, hydrants, surface boxes and manhole covers.

Accessories associated with the valves are also specified.

1.2 Definitions

The definitions given in the relevant standards, which are referred to in the specification, shall apply for the terms used in this specification.

1.3 Reference Standards

The following standards are referred to in this section;

BSEN ISO 1461:2009 Hot dip galvanized coatings on fabricated iron and steel articles. (Specifications & test methods)

BSEN 1982 : 2008 Copper and copper alloys. Ingots and castings.

BSEN 1092-2:2003 Flanges and their joints- Circular flanges for pipes, valves, fittings and accessories, PN designation

BSEN 1171 : 2002 Industrial Valves. Cast Iron Gate Valves.

BSEN 12334:2001 Industrial valves, Cast iron check valves

BS EN 1563:1997 Specification for Spheroidal graphite cast iron. BSEN 593 : 2004 Industrial Valves Metallic Butterfly valves.

BS 5163 : 2004 Predominantly Key-operated cast iron gate valves for waterworks purposes.

BS 750 : 2006 Underground fire hydrants and surface box frames and

covers

BSEN 10293: 2005 Steel castings for general engineering purposes

BS 5834 :Part 2 :1983 Specifications for small Surface boxes. Surface Boxes, guards and underground chamber for gas and water work purposes.


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BS EN 124 : 1994 Gully tops and manhole tops for vehicular and pedestrian areas. Design requirements; type testing, marking quality control.

AWWA C 502-80 Dry Barrel Fire Hydrants

BS 1212 : Part 2 : 1990 Diaphragm type float operated valves (copper alloy

body) (excluding floats)

BS 1212 : Part 3: 1990 Diaphragm type float operated valves (plastic bodied) for cold water services only (excluding floats)

BSEN 558: 2008 Industrial Valves. Face to face and centre to face dimensions of metal valves for use in flange pipe systems. PN and class designated valves.

BSEN 1074 –1: 2000 Valves for water supply. Fitness for purpose

requirements and appropriate verification tests. General Requirements.


requirements and appropriate verification tests. Isolating valves.


requirements and appropriate verification tests. Check valves.


requirements and appropriate verification tests. Air valves.

Note: The year within brackets gives the year of amendments made.

1.4 Records and Drawings for Items(Valves and other Ancillary items) to be

Supplied

The following records and drawings of all types of valves shall be made available by the supplier for inspection. - Drawings showing overall dimensions, valve construction and settings

- Data related to pressure ratings, weights and materials of manufacture (each

component) - Test certificates of works tests

- Performance data of air valves - Seating design and the seating materials of butterfly valves


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1.5 Materials of Manufacture

All materials of manufacture shall be suitable for use with water at temperatures up to 45 deg. C.

Valve body casting shall be ductile iron complying with BS EN 1563 :2004 for diameters above DN 150, while CI valve body casting is acceptable for below DN 150 and shall be capable of withstanding the test pressures specified. The castings shall be close grained, sound, smooth and symmetrical, and shall be carefully cleaned and dressed off. No stopping or plugging will be permitted in the case of air holes appearing in the castings.

Unless otherwise specified, all standard valves shall be flanged type where flanges shall be of PN 16 and complying with BSEN 1092-1 :2007. The direction of closing of valves shall be “clockwise” and hand wheels shall be permanently marked with the words "open" and "closed" and a direction arrow.

All materials shall comply with the appropriate British Standards or equivalent. All castings shall be free of blowholes and other defects.

Sluice valves and butterfly valves shall be suitable for flow in either direction. All standard valves shall be suitable for frequent operation and for infrequent operation after long periods in the open or closed condition.

All non-metallic materials to be provided shall be listed in the current "Water Fittings and Materials Directory" published by the Water Research Centre, UK, or approved equivalent publication, as having passed full tests of effect on water quality under the requirements for the testing of non-metallic materials for use in contact with potable water.

The Engineer shall have the right to reject any casting, forging, bearing etc and the contractor shall replace any such defective parts at his own expense.

1.6 Testing

General The manufacturer shall notify the Engineer at least thirty working days prior to

factory tests. The Engineer reserves the right to witness all tests. (i) Performance Test

Each valve, gate and appurtenance shall be shop-operated three times from the fully closed to the fully opened position, and the reverse, under a no-flow condition, to demonstrate that the complete assembly is workable.


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(ii) Leakage Test (Closed Position)

(a) For Internal Pressure Valves, gates and appurtenances shall be shop-tested for leaks in the closed positions. The hydrostatic pressure shall be applied to one face of the disc for the full test duration at the working pressure when the valve is in closed position. This shall be repeated to the other face of the valve too. The length of test shall be at least 3 minutes and there shall be no indication of leakage past the valve during the test period. The test pressure shall be given in the Table below.

PN Test Pressure (PFA) (Bars) Duration (Minutes) 16 25 3

25 35 3

(b) For External Pressure Valves shall be leak tight to ingress of air, water or any other foreign matter.

a. Hydrostatic Test Valves specified shall be hydrostatically tested. Hydrostatic tests shall conform to the following; With the valve disc in fully open and a slightly open position, internal hydrostatic pressure equivalent to 150% of the specified working pressure a specified in the table below shall be applied to the inside of the valve body of each valve for a period of 3 minutes. During the hydrostatic test, there shall be no leakage through the metal, the end joints, or the valve shaft seal; nor shall any part be permanently deformed. While undergoing testing, the valve body shall be struck with a hammer several times.

PN Test Pressure (PFA) (Bars) Duration (Minutes) 16

25 3

25

35 3


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(iv) Seat Tightness Test

Type of valve Test Procedure Sluice valve Ball float valve

1. Fill in the valve cavity including if appropriate, the bonnet cavity with water.

2. Move the obturator to the closed position. 3. Apply the test pressure, which is 1.1 times the

allowable differential pressure at room temperature, and maintain the test pressure for 3 minutes.

4. Determine the leakage rate. 5. Repeat 3 and 4 inclusive for the other side of the valve. See NOTES 1,2,3 and 4

Butterfly Valve 1. Fill the valve cavity with water. 2. Move the obturator to the closed position. 3. Apply the test pressure, which is 1.1 times the

allowable differential pressure at room temperature in the direction to unseat the obturator and maintain the test pressure for 3 minutes.

4. Determine the leakage rate. See NOTE 5

Check Valve 1. Fill in the downstream valve cavity including, if appropriate, the cover cavity with water.

2. The test pressure, which is 1.1 times the allowable differential pressure at room temperature in the direction tending to close the obturator and maintain the test pressure for 3 minutes.

3. Determine the leakage rate.

NOTE 1. The procedure described may not ensure pressurization of the integrate

space of double seated valves and may not therefore permit verification of the leakage rate of the downstream seat. When such pressurization is a requirement of the product or performance standard or is required by the purchaser, it is necessary to carry out step 3 before step 2.

2. Valves which incorporate “double block and bleed” design feature have the bleed plug removed prior to the test in order to prove the “double block and bleed” capability.

3. Valves with independent double seating (such as two piece obturator or double-seated valves) may be tested by applying the test pressure between the seats and checking each side of the closed valve.

4. Soft seated ball float valves previously subjected to a liquid seat test pressure may have a reduced performance capability in some subsequent services at low differential pressures. If a liquid seat test pressure is specified and is carried out before a low pressure gas seat test, it may be necessary to allow time for the seat material cover.

5. Valves with symmetrical seating may be tested in either direction.


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(v) Field Testing When the valves, gates and appurtenances have been completely installed and as soon as operation conditions permit, they shall be given a field test by the Engineer to demonstrate that they have been suitably installed, that they meet all requirements, are in good operating condition and are, in every way, adequate for the service intended.

1.7 Coating

All exposed cast iron or ductile iron components of valves to the external environment or to the water contained in the valve shall be fully coated to provide protection against corrosion. The external and internal surfaces except mating surfaces of all valves shall be treated with an epoxy coating, a bitumen solution or any other material acceptable to the purchaser at the place of manufacture. Threaded and exposed machined surfaces liable to rusting shall be adequately protected in accordance with BS 5163 : 2004.

2.0 Types of Valves 2.1 Sluice Valves

The sluice valves for pipeline installation shall comply with the BSEN 1074:1-2000 and BSEN 1074 : 2 – 2000 or BS 5163-1:2004 for diameters up to and including 600 mm and BSEN 1171:2002 for diameters above 600 mm and shall be of PN 16 pressure rating, for potable water applications.

Sluice valves shall be standard inside screw, wedge gate valves with resilient seating for diameter from DN 50 – DN 300 inclusive and metal to metal seating from diameters above DN 300. The valve body shall be ductile iron or cast iron upto and including DN 150 complying with BS 5163-1 : 2004 and BSEN 1563 : 2004. For diameters above 150mm, the valve body shall be ductile iron complying with BSEN 1563: 2004. Valves shall have stainless steel stems, machined bronze or gunmetal mating faces securely fixed to the valve body, stuffing box and gland type or approved type stem seal, EPDM / SBR seals at joints between castings.

All Tee-Key operated valves shall be provided with valve cap as per BS 5163 : 2004. By pass arrangement shall be provided for valves of DN 300 and above. Directions of closure of the valves shall be ‘clockwise”. In case of hand wheel operated valves, the hand wheels shall be indelibly marked with words “open” and “close” with direction arrows. The maximum differential pressure in operation for valves shall be as given in items description of the valves in the BOQ or as given in the drawings. Where necessary valves above 300mm diameter shall be provided with gearing to achieve the designed manual operation of valves where it should be assumed that the maximum torque exerted by one man is 130 Nm.

Motorized (Motor operated) valves shall be provided for diameters 500mm and above as given in the item description of BOQ or as given in the drawings.


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Valve spindles shall be of the internal non-rising type. Hand wheels shall be made of cast iron and shall have arrows and words ‘open’ and ‘close’ cast on to indicate direction of rotation for opening and closing the valve.

All sluice valves shall be subjected to all type testing in accordance clause 1.6 above including 'open ended' works test of which the test certificates issued by the manufacturer to this effect, shall be submitted.

The face-to-face (FTF) dimensions of the sluice valves as specified in BSEN 558:2008 shall be as follows.

Sluice Valves - Series 3

Diameter (mm)

FTF dimension (mm) PN 10/PN 16 PN 25

10 102 - 15 108 140 20 117 152 25 127 165 32 140 178 40 165 190 50 178 216 65 190 241 80 203 283 100 229 305 125 254 381 150 267 403 200 292 419 250 330 457 300 356 502 350 381 572 400 406 610 450 432 660 500 457 711 600 508 787 700 610 - 800 660 - 900 711 - 1000 813 -

2.2 Butterfly Valves

Standard butterfly valves shall conform to BS EN 593: 2004 for PN 16 (i.e. 16 bar) pressure rating. However higher PN range shall be provided as given in the item of BOQ.

Except where otherwise specified, all butterfly valves shall be equipped with manual operators with hand wheels and shall be resilient seated and shall give tight closure


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against unbalanced water pressure in either direction. The unbalanced water pressure shall be the design pressure rating of the valve.

The valve body shall be ductile iron complying with BS EN 1563 : 2004 and shall be designed to withstand the maximum working pressure specified and the maximum differential pressure of 0.6 MPa.

The manufacturer's preferred direction of flow for the valve shall be clearly marked on it.

The valve seat shall be replaceable and be formed of EPDM/SBR or other approved resilient material. Seats shall be of a design that permits removal and replacements at the site of installation. The valve seat shall be securely clamped into a machined groove in the valve body or to the edge of the disc by seat retention members or other equivalent retention device, in such a manner as to prevent leakage of water under the seats and to hold the seat securely in position during opening and closing of the valve disc. The seat retention members shall be of stainless steel and shall be securely fastened to the body or disc with stainless steel fasteners. The valve disc shall be made of ductile iron. Disc edges shall be machined with rounded corners and shall be polished to a smooth finish. The valve disc shall rotate through an angle of 90 degrees from the fully opened to the fully closed position and the seat shall be of such design as to allow the valve disc to seat at an angle normal to the axis of the pipe when the disc is in the fully closed position. Adjustable mechanical stops shall be provided in the valve body to be capable of absorbing full operating torque with a minimum design safety factor of 5 (five).

The shaft and nuts and bolts shall be fabricated of stainless steel complying with relevant provisions of BS 970:1996. The shaft and disc fixing shall be capable of absorbing the full operating torque with a minimum design safety factor of five. Shaft seals, when used, shall be EPDM / SBR rubber O-ring type. Packing shall be either rubber O-ring or self-adjusting chevron type.

When all the seat retention members are in place, the finished edges shall fit closely and the surface shall be smooth with all fastenings set flush in the water passage so as to offer the least resistance possible to the flow of water through the valve.

Valve seats which extend over the face of the flanges to secure the seat in place, or which require surface grinding and/or hand fitting of the disc; or designs which require the adjoining pipe flange to retain the seat in place and resist line pressure, shall not be supplied.

Operating gear for butterfly valves shall be of the fully enclosed type. Valves shall be suitable for operation by one man at all pressure conditions that can apply. A valve position indicator shall be provided for butterfly valves in chambers. Where a hand wheel is used for operating such a valve, the indicator shall be clearly visible from the hand wheel operating position. Where a containing chamber is not shown, butterfly valves shall be specially adapted for buried use. Inline valves shall be operated by means of a hand wheel or tee key and be provided with gearing to prevent rapid


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closure of the valve. Gear ratios shall be at least 20:1. The valve bodies shall be protected by a bitumen coating and the valve discs by a Nylon Coating or similar.

All butterfly valves shall be tested at the manufacturer's works in accordance with BS EN 593:2004 as specified here and as per clause 1.6 above and under 'open-end' conditions. The seat test shall be for tight closure under maximum unbalanced water test pressure in either direction. The maximum permissible leakage for each valve shall be 0.05 liter per hour per 100 mm nominal diameter of the valve. The word “CLOSE” or its abbreviation and the arrow mark indicating the direction of rotation to close the valve shall also be cast on the cover of the body. The face-to-face (FTF) dimensions of the sluice valves as specified in BSEN 558 : 2008 , Table 4 shall be as follows

Diameter

(mm)

FTF dimension (mm) PN 2.5,6,10,16,25 PN 40

40 106 140 140 50 108 150 150 65 112 170 170 80 114 180 180 100 127 190 190 125 140 200 200 150 140 210 210 200 152 230 230 250 165 250 250 300 178 270 270 350 190 290 290 400 216 310 310 450 222 330 330 500 229 350 350 600 267 390 390 700 292 430 430 800 318 470 470 900 330 510 510 1000 410 550 550 1200 470 630 630 1400 530 710 710 1600 600 790 790 1800 670 870 870 2000 760 950 950

2.3 Air Valves

All air valves for water supply shall comply with the BSEN 1074-4:2000. Air valves shall be constructed so that internal working parts, which may become necessary for repairs shall be readily accessible, removable and replaceable without use of special tools and removing the valve from the line. Standard air valves shall be designed so


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that the floats seat against orifices without leakage at all pressures between 0.1 bar and the maximum field test pressure. The design for the floats and seats shall be such that the risk of adhesion is a minimum and shall be of a type proved by experience to be suitable for the duties required. All valves shall be suitable for operation under working pressures conforming to clause 4.3 and Table 1 of BSEN 1074-1:2000, Valves shall be so designed that the floats cannot be held or blown shut against the orifices by air pressure or turbulence due to escaping air.

Standard air valves shall have a minimum pressure rating of 16 bar and in all cases shall be supplied with PN 16 (i.e. 16 bar) flanges, complying with BS EN 1092-1: 2007. However higher PN range shall be provided as given in the item of BOQ.

2.3.1 Single Orifice Type Single orifice type air valve shall be of cast iron or ductile iron body and single float actuated air valves with flanged ends. Small orifice air valves shall have an orifice diameter of not less than 1.5 mm and shall be designed for automatically releasing air accumulated in pipelines during normal working conditions so as to prevent accumulations of air interfering with pipeline capacity. Small orifice air valves shall be provided with an isolating valve. The valve shall be capable of discharging air out of the pipe line in according to the graph given below. General components of the single orifice air valves is given in Annex D1. Air Discharge of Single Orifice (Small Orifice) Air Valve


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Large orifice air valves shall be required to release or admit air while the pipeline is being filled or emptied and also to perform surge control functions. The airflow characteristics of air valves shall be in accordance with BSEN 1074-4:2000 and they shall be capable of passing air out of the pipeline under a differential pressure of 0.5 bar, and into the pipeline at a differential pressure of 0.2 bar at rates depending on the graph given below;.

Large Orifice air valves shall be provided with separate isolating valve.


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2.3.2 Double Orifice Type

Double orifice valves shall comprise one large orifice air valve and one small orifice air valve integrated into a single unit assembly and having a single pipeline connection. It shall have cast iron or ductile iron body and double float actuated air valves with flanged ends.

Double orifice air valves shall be provided with a separate isolating valve. Isolating valves must be so arranged that they can be closed from the ground surface above, with a tee key even when the air valve chamber is flooded. Where required, a short length of double-flanged pipe could be supplied to increase the height above the main to suit the operational requirements depending on the depth of installation of Air valve. Air valves shall be insect proof at the outlet vents leading to the atmosphere.

Tests shall be carried out on all types of air valves, as specified in BSEN 1074-4:2000 and BSEN 1074-1:2000 and as mentioned below and the contractor shall submit the manufacturer’s certificates certifying that such tests have been conducted satisfactorily.

General components of Double Orifice Air Valve is given in Annex D2.

The valve shall be capable of discharging air out of the pipe line in according to the graph given below.

Air Discharge of Double Orifice (Small Orifice) Air Valve

Air Discharge of Double Orifice (Large Orifice) Air Valve


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(a) Body Strength Test

Each complete valve shall be water tested for strength using a test pressure 1.5 times the specified working pressure. No damage or permanent deformation of the valve body, ball or seat shall occur and there shall be no leakage through the metal or any joints of the body.

(b) Leakage Test

Each complete valve shall be water tested at all pressures between 0.1 bar and the maximum field test pressure for the valve and the seat shall be drop tight throughout this range of pressure.

(c) Performance Tests

One valve of each size shall be tested as follows; (i) Air shall be introduced under the flange at the minimum outflow rate

specified above for the size of pipeline being tested. The pressure difference required to maintain this flow shall not be more than 0.5 bars.

(ii) Air shall be exhausted from beneath the flange at the minimum inflow

rate specified above for the size of valve being tested. The pressure difference required to maintain this flow shall not exceed 0.2 bars.

All air valves shall be coated as given in clause 1.7 above.


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2.4 Check Valves

Unless otherwise specified, check valves shall be swing type conforming to BSEN 12334:2001 with a pressure rating of PN 16 (i.e. 16 bar). Check valves shall be constructed so that disc, seat, seat rings and other internal working parts, which may become necessary for repairs, shall be readily accessible, removable and replaceable without use of special tools and removing the valve from the line. The valve body and the disc shall be of ductile iron complying with BS EN 1563 : 1997 and having smooth operating stainless steel hinge pins with gun metal bushes, EPDM / SBR encapsulated discs. They shall possess high speed closing characteristics with minimum shock on closing. All valves shall be tested to BSEN 12334:2001 and as specified in BSEN 12266-1 : 2003 and the test certificates issued by the manufacturer shall be submitted. All check valves shall be coated to as specified in clause 1.7 above. The flange drilling shall comply with BSEN 1092-1:2007, BSEN 1092-2:2007 or BSEN 1092-3:2007.

2.5 Pressure Reducing Valves

Pressure reducing valves shall be designed to reduce a constant or variable inlet pressure to a predetermined constant outlet pressure, at flows varying from the maximum capacity of the valve to zero flow.

All valves shall be suitable for use with water temperature up to 400C and in climatic conditions encountered in Sri Lanka such as humidity 85%, dusty environment, corrosive atmosphere etc. Valves shall be minimum rating of 10 bars and shall provide to higher ratings of 16, 25 or 40 when specified in the item of BOQ. The valve operation shall be achieved by the inter-action of the inlet pressure, outlet pressure and an intermediate pressure, which is produced by a pilot valve or relay system acting on the upper side of the main valve. Other equally effective and reliable systems may be accepted by the Engineer. Operating primary pressure of 16 bar and at an adjustable secondary pressure range 0f 25 or 40 bars shall be as specified in the BOQ.

The pilot valve or relay system shall be actuated by a diaphragm connected to the outlet pressure on its underside and a constant pressure on its upper side derived either from weights or from a spring. The weights or spring shall be capable of an adjustment. Gauge indicating upstream pressure and downstream pressure shall be incorporated. Two pressure gauges shall be provided with the valve.

Nominal pressure rating shall be 16 bars, unless otherwise stated.

Body ends shall be flanged and drilled to BS EN 1092-1:2007, with a pressure rating of PN 16. Materials for construction of the valve shall be ductile iron, grey cast iron, stainless steel (SS316 or higher) or Equivalent and shall be non-corrodible, hard wearing and suitable for use with potable water. Gunmetal, aluminum bronze and stainless steel shall be used for internal components.


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Marking of valves shall include the manufacturing standard; manufacturer’s name or trademark; nominal diameter (N.D.) in mm; pressure rating in bars; Flow direction; an individual serial number which relates directly to the manufacture’s test certificate; and month and year of manufacture.

All valves shall be tested to the appropriate test pressure as specified in Clause 4 of BSEN 1074 – 1 : 2000 and as given below at the manufacturer’s works, and shall be supported by a test certificate from the manufacturer. The Supplier shall provide the original manufacturer’s test certificate. The certificate shall relate to the individual number cast on each valve and shall give the date of test and the performance of test with test pressure and the time.

PN Test Pressure (PFA) (Bars) Duration (Minutes) 16

25 3

25

35 3

2.6 Pressure Sustaining/Relief Valves

Pressure sustaining valves shall be capable of maintaining a constant pressure in the main upstream of the valve. They may be used to reduce excess pressure when installed in a branch main.

Operation shall be achieved in a similar manner to the pressure reducing valve except that the relay system shall be actuated by the upstream pressure. Manufacturing of the valve shall generally be in accordance with the specification for pressure reducing valves.

Testing shall be carried out according to clause 1.6 hereof. 2.7 Flow Control Valves

Flow control valves shall be designed to prevent the rate of flow rising above that specified for the particular application, regardless of the operating pressure in the system upstream or downstream of the valve. The valve operation shall be achieved by the operation of a relay system responding to the pressure difference measured across an orifice in the flow upstream of the valve. The manufacturing of the valve shall be generally in accordance with that specified for pressure reducing valves above.


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2.8 Altitude Valves Altitude valves shall be designed to control inflow into an overhead tank or reservoir, the valve being installed in the main line to the tank and controlled by a small diameter ball valve in the tank, so that when the tank is full, the ball valve closes, which in turn shuts the main valve. The valve operation shall be achieved by the interaction of the inlet pressure, the pressure in a small bore pipe in to the ball cock and an intermediate pressure produced by a pilot valve or relay system acting on the upper side of the main valve which in turn shuts the main valve. The pilot valve or relay system shall be actuated by a diaphragm connected to the small bore pipeline to the ball valve on its underside and having a constant pressure on its upper side derived from either weights or a spring. Manufacturing of the valves shall generally be in accordance with the specification for pressure reducing valves.

2.9 Ball Float Valves

Ball float valves shall be designed for installation on the inlet pipe to a storage tank to shut the water off automatically when it reaches a predetermined level. They shall be of the single or double beat type or pilot operated with direct float and lever operation.

Valves shall be designed for the working pressure specified and shall be tested for leakage at that pressure, when they should be drop tight. They shall be tested for body and valve element strength with the valve closed and a test pressure 1.5 times the working pressure applied to the inlet end.

The body end shall be flanged, faced and drilled to BS EN 1092 – 1 : 2007

Valves shall not contain brasses containing more than 5% zinc. Gunmetal (to BS EN 1982:2008 Grade LG 2), aluminum bronze or nickel copper alloy may be used for internal components. The body or stopper shall be of ductile iron or grey or Meehanite cast iron.

Floats shall be copper or glass fibre. The lever and links shall be of mild steel with bronze pins.

Where a stilling tank arrangement is required it shall accommodate a cheese type float mounted on a central tube connected to the valve operating lever and sliding vertically on a guide rod secured to the base of a galvanized wrought iron cylindrical tank perforated at the base.

2.10 Flap Valves

Flap valves shall have frames and doors of ductile iron to BS EN 1563 : 1997, sealing faces of gunmetal to BS EN 1952:2008 Grade LG 2 or LG 4 and hinge pins and links of ductile iron, steel nickel iron or stainless steel. They shall be flanged for mounting to pipe work or bolting to concrete. Sealing surfaces of flaps and frames shall be of non-ferrous metal (excluding aluminium) accurately machined to ensure a watertight fit in the closed position. All flaps shall be double hung and seat off the vertical.


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In case of plastic flap valves they shall have doors constructed from non-toxic, ultraviolet stabilized, flexible reinforced plastic material and the frames shall be fabricated from mild steel, blast cleaned and painted with 25 microns of two pack epoxy blast primer and one 75 micron coat of micaceous iron oxide two pack epoxy.

All immersed steelwork shall be hot dipped galvanized to BS 729 or as appropriate. Nuts and bolts shall be galvanized. Flanges shall be of PN 16 conforming to BS EN 1092 – 1 : 2007., coated in either fusion bonded epoxy, minimum thickness 150 microns or cold applied black bitumen.

3.0 Extension Spindles, Tee - Keys and Caps

The depths of installation of all valves are as indicated in the BOQ descriptions (or as shown on the drawings) and a Tee - Key for the operation of valves shall be supplied in the following manner. Four Tee - Keys for each size of valves to be supplied. The maximum length of Tee key shall be limited to 1m and Valves shall be provided with extended spindle to the Valve. The material of Tee - Keys shall be galvanized mild steel. In case extension spindles are necessary, extension spindles shall be provided with suitable bearings, which are rigidly held on brackets or stays. Bearings and extension spindles shall be suitably protected against corrosion. Where a valve does not require an operating or extension spindle, the valve spindle shall be protected with a properly fitting cap as per BS 5163: 2004.

4.0 Fire Hydrants General

Fire hydrants shall be supplied and installed at the locations shown on the key plan and drawings and distribution pipelines. The exact locations of the fire hydrants shall be identified at site in the presence of the Engineer’s Representative and approved by the Engineer. (a) Screw down Type

Screw down fire hydrants shall conform to BS 750 : 2006 (type 2) with “captive” internal valve. The hydrant body material shall be ductile iron, which complies with BS EN 1563 : 2004.

The inlet flange shall be of PN 16 complying with BS EN 1092 – 1 : 2007 and

shall be faced and drilled to table ‘E’ of BS 10:1962. The outlet piece shall be Gunmetal complying with BS EN 1982:2008 Grade LG 2 or stainless steel complying to BSEN 10088-1 with minimum chromium content of 13% or


6 - 70

copper alloy. The hydrants shall be of round threaded conforming to BS 750 : 2006.

The hydrant body shall be capable of withstanding a pressure of 24 bars and

the valve and seat pressure of 16 bars. The test certificates of body and seating tests shall be submitted.

The outlet cap shall be of polypropylene or equivalent, without threads and shall be securely attached. The direction of closing of hydrant valve shall be clockwise.

(b) Dry - Barrel Type

Dry-Barrel type Fire Hydrants shall comply with ANSI/AWWA C 502-80 standards or an equivalent with the following requirements; i. Buried length shall be 4.5 feet. (1.35m) ii. Number of hose and pump outlet nozzles shall be two. iii. 2.5 inches (63.5 mm) nominal inside diameter two number outlet nozzles

shall be provided with round threads to BS 750:2006. iv. Size of hydrant shall be 4 inches (100 mm). v. Inlet connection shall be 6 inches (150 mm) in diameter flange type (side

inlet). Suitable Double Flanged Ductile Iron Reducers shall be supplied to connect the Fire Hydrants to the existing pipe diameter flanges.

The bonnet, foot piece or elbow, packing plate, gate, bottom plate and outlet nozzle cap should be of ductile iron while miscellaneous structural parts can be grey iron, ductile iron or malleable iron. Valve seats, seat rings for the main valve and the drain valve and outlet nozzle shall be made of grade A,B, D or E bronze. The threaded portion of the operating stem or threaded stem nut (or sleeve) shall be made of grade A,B,C,D or E bronze too. The Supplier shall supply the necessary gaskets, conforming to BSEN 681-1 and nuts, bolts and washers for the 6 inches (150 mm) flange joint between the reducer and the Fire Hydrant.

vi. Direction of rotation of the operating wheel to open the hydrant shall be

counter clockwise. vii. Colour of the finish paint above the ground line shall be red. viii.The following parts may be made out of grey or ductile cast iron, but the

Bidder has to submit with the tender the material he is going to use: Barrel, top or bonnet, foot piece or elbow, packing plates, gates, bottom plates, outlet nozzle caps and miscellaneous structural parts.


6 - 71

5.0 Tools

The Contractor shall supply two complete sets of tools adequate for the erection and maintenance of all valves, hydrants and other fittings supplied.

6.0 Surface Boxes

Surface boxes shall be Ductile iron, grade “A” heavy duty complying to BS 5834 Part 2 : 1983 with the minimum clear opening sizes (mm), of 100mm, 135mm,225mm and 300mm depending on the location and as specified in the BOQ. Surface boxes shall be painted before installation with two coats of bituminous paint. They shall be with captive hinge arrangement to prevent vandals and with suitable watertight arrangement to prevent ingress of surface water into the keyhole. The hinge pin shall be made from steel or ductile iron manufactured to suit the design and dimension of the unit. The diameter of the hinge pin shall not be less than 6mm. The lids or covers of surface boxes shall have cast in-letters of words in English to indicate the function of the fittings as “FH, WO, SV, METER” and also the marking “NWSDB – WATER” in suitable size, cast in raised letters.

7.0 Manhole Covers and Frames Manhole covers and frames shall be of class D 400 as per BS EN 124: 1994 unless

otherwise stated. They shall be made from Ductile Iron. The covers shall be non-ventilating non rock, black bitumen coated. The keyways

shall be closed and the couplings bolts, etc. shall be galvanized. They shall be with clear opening of 600 mm, with captive hinge arrangement to

prevent vandals and with suitable watertight arrangement to prevent ingress of surface water into the manhole. Manhole covers for fire hydrants shall comply with requirements of fire authority while the manhole covers for air valves and washouts shall be ventilated type. The manhole covers for sluice valves shall be watertight. The manhole covers shall have letter or words in English to indicate the function of the fitting, “FH, WO, SV” and also marking “NWSDB – WATER ” in suitable size, cast in raised letters.


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ANNEX D1 General Components of the Single Orifice Air Valve


6 - 73

ANNEX D2 General Components of the Double Orifice Air Valve


9. PENSTOCKS All penstocks shall be of the flatback type and shall be drop-tight in the ranges of duty

for which they are required. Penstocks, frames and doors shall be of best quality cast iron complying with BS 1352

with two annular gunmetal sealing faces on frame and door. An adequate number of cast iron wedges shall be provided on the doors of adjustable gunmetal faced wedge blocks as necessary fixed to the frames. The frame shall be of substantial construction.

The gunmetal shall comply with the requirements of BS 1400. All screw penstocks shall be provided with a mild steel spindle screwed for anti-

clockwise opening and running in a gunmetal nut housed in a suitable head gear which shall have handwheel or key for operation as detailed in the Bill of Quantities. The extended spindles shall be of cadmium plated mild steel with protection tubes; wherever their length so requires, steadying brackets shall be provided.

Suitable bevel gearing and anti-friction devices such as ball bearing thrust collars shall

be provided as necessary to enable each penstock to be operated. Full details must be given with the tender.

All headstocks shall have a forged steel rod and be complete with a gunmetal index

pointer working over a polished and graduated gunmetal indicator plate fixed to the side of the pillar.

NWSDB/SBD/Civil-Major : Specifications 6 -75 CAPC : MPC: DPC :- December 2011 – Version 2

10. FLOW METERS AND WASTE METERS 1.0 General 1.1 Meters shall be suitable for waterworks purposes for measurement of flow of

potable water. 1.2 Differential pressure, inferential and waste meters shall have flanged ends faced

and drilled and conform to the dimensions specified in B.S. 4504. The flanges of the waste meters may have slotted holes.

1.3 Meter bodies shall be hydraulically tested for a period of not less than 15 seconds

to the hydrostatic test pressure stated in the Bills of Quantities and shall be suitable for the working pressure stated therein.

1.4 Recorder charts shall be of the waxed type suitable for marking with a stylus. 1.5 The Contractor shall supply with each recording instrument two spare stylus,

refill quantity of any working fluid such as mercury and one hundred charts for each recording instrument. The charts shall be headed as specified in the notes forming a part of this Specification. Charts shall be graduated in cubic metres and the Tenderer shall submit specimen copies with his tender for approval. The charts shall be suitable for use in the tropical conditions previously mentioned.

1.6 The chart recorder drums for use on inferential waste meters shall be spring

driven and suitable for rewinding when the charts are changed. 1.7 Each meter shall bear the mark of the Manufacturer and indication of its nominal

diameter where appropriate. Such marks may be either cast on, or stamped on. 1.8 Differential pressure and inferential meters shall be suitable for placing in

chambers which may become flooded. Waste meters shall be similarly suitable when the recording mechanism is not in place.

1.9 The Contractor shall label and clearly mark all items in indelible paint as

specified in the notes forming a part of this Specification. All lettering and numbering shall be at least 50 mm high. In addition, all fittings shall be marked with the corresponding item numbers in

the Bills of Quantities, or other number notified by the Engineer. 1.10 Every precaution shall be taken to avoid damage to meters, instruments and

fittings, which shall be carefully packed in boxes and crates.


1.11 Delicate parts of recording instruments shall be packed separately in purpose made polyurethane foam containers, or otherwise carefully protected. Moving parts of instruments shall be restrained during transit.

1.12 Each package shall be clearly labeled with the numbers and size and particulars

of the contents. 1.13 The Tenderer shall give full particulars of all meters and instruments offered in

the Schedule of Particulars, supported by drawings and dimensions. 2.0 Differential Pressure Meter 2.1 The differential pressure meter shall be of the venturi Tube or `Dall' Tube type. 2.2 Indicating, integrating and recording instruments shall conform with B.S. 1986. 2.3 Instruments shall be fitted with linear scales. 2.4 Recorder Charts shall be of the circular type and suitable for replacement not

more frequently than once per week. Chart speed shall be such as will give a clear indication of variations of flow. The design shall allow for site adjustment of the chart speed.

2.5 The maximum range of the instruments shall be 25% greater than the normal

maximum indication. 2.6 The circular chart recorder and integrator shall be spring driven and suitable for

rewinding every seven days. 2.7 The indicator integrator and recorder will be mounted in a small building over or

close to the differential pressure producer. The tenderer shall indicate by a drawing the suggested relative positions, dimensions, and levels of the differential pressure producer, chamber and associated small building.

2.8 The indicator and recorder shall read in cubic metres. The integrator mechanism

shall register in cubic metres. 3.0 Inferential Meters 3.1 Inferential meters for district metering shall be of the helix type with integration

of flow registered by 7 digit cyclometer in cubic metres. 3.2 The entire mechanism of an inferential meter shall be removable from the body

for cleaning and maintenance purposes. A blank cover shall be supplied with each meter.


4.0 Waste Meters 4.1 Waste water meters shall be of the gate type. Recording mechanisms shall be

suitable for fixing in position before, and removing after waste detection tests are carried out. The recording mechanism shall be supplied in stout lock-up boxes.

5.0 Meters for Service Connections to Domestic, Commercial and Industrial Premises 5.1 All meters shall be of the "Dry Dial Type". 5.2 The body shall be of an alloy of metal of adequate strength and durability to

withstand corrosion and wear and tear. 5.3 The cover lids shall be so designed and manufactured that they cannot be easily

broken or detached from the meters. 5.4 Service meters shall be robust, have a high degree of accuracy of measurement at

low flows replaceable working parts and cyclometer counters. 5.5 The meters shall be calibrated to read in cubic metres and liters, with a return to

zero at not less than : Size of Meter Integrated quantity Up to and including 80 mm 99,999 m3 Larger than 80 mm 999,000 m3 5.6 The head losses caused by installing meters in service pipes should not exceed

the following at the maximum continuous flow rates quoted.

Size of Meter

(mm)

Max. Continuous Flow rate

(Cubic metres/hr)

Approx. head loss

(Metres)

15

20

25

40

50

1.5

2.5

3.5

6.5

8.0

2.5

2.5

2.5

1.0

0.75


Size of Meter (mm)

Max. Continuous Flow rate (Cubic metres/hr)

Approx. head loss (Metres)

80

100

150

13.0

25.0

42.0

0.70

0.4

0.4

5.7 The Contractor shall state in the Schedule of Particulars the head losses which

will occur in the meters he proposes to supply at the maximum continuous flow rates quoted.

5.8 For sizes up to and including 40 mm, each meter shall have union connections to

enable the body to be removed from the service pipe. A male connection screwed B.S.P. shall be provided for connecting to a stop valve on the upstream side of the meter, and a similar male connection shall be provided on the downstream side of the meter.

For sizes 50, 80, 100, 150 and 200 mm, the meters shall be flanged to Table

16/11 BS 4504. Tenderers shall state the length of straight pipe required, if any, on each side of the meter for accurate measurement of flow.

5.9 Direction of flow arrows shall be integral with the body metal. 5.10 The meters shall have strainers in the body of the meter on the upstream side of

the mechanism. 5.11 All meters shall be suitable for horizontal or vertical installation.

5.12 The Contractor shall state the percentage minimum accurate registration in liters per hour for sizes up to 50 mm and in cubic metres for larger sizes, the recommended maximum continuous rate of flow, and the recommended maximum daily and monthly flows.

5.13 Accuracy of the meter reading shall be within the range of +2% when tested at

flows ranging from 150 litres/hr. to the maximum flows stated in Clause 8.30.


11. STEEL PIPES AND FITTINGS 1. Standards Steel Pipes and Fittings shall be supplied in accordance with:- (a) The American Petroleum Institute Specification for Line Pipe, A.P.I. Standard

51 (25th Edition, April 1970) together with the additional clauses or amendments set out in this Specification or,

(b) The American Petroleum Institute Specification for Spiral Weld Line Pipe,

A.P.I. Standard 5 L S (5th Edition, April 1970) together with the additional clauses or amendments set out in this Specification, or,

(c) Any other National Standard or Specification acceptable to the Engineer as

providing Equivalent or better quality of materials and workmanship together with additional clauses set out in this Specification.

2. Grade of Steel used in Pipes and Fittings 2.1 The Grade of steel used in the pipes and fittings shall be Grade A for welded

pipe in accordance with Table 3.1 of the A.P.I. Standard. 2.2 The Contractor shall submit to the Engineer ladle and check analyses in

accordance with Section 3 Clauses3.2 and 3.3 of the relevant A.P.I. Standard. 3. Welding 3.1 Pipes may be manufactured by either an electric resistance welding process or

by a submerged are welding process. Pipes less than 200 mm nominal diameter may be manufactured by seamless process at the option of the Tenderer.

3.2 Fittings shall be manufactured by an electric resistance welding process

unless an alternative method is approved by the Engineer.

3.3 Skelp end joints shall not be permitted within any pipe or fitting. Section 2.2 of A.P.I. Standard 5 LS shall be deleted.

4. Manufacturing Process 4.1 The Tenderer shall at the time of tendering submit full details of the

manufacturing processes he intends to use.


4.2 The Contractor shall advice the Engineer of all details of fabrication, welding, cleaning and coating procedures prior to the commencement of fabrication. Such details shall include but not be confined to:

(1) Type or brand of steel (2) Welding process

(3) Type and size of electrodes, number of bends and rate of deposition of weld metal.

(4) Electrical characteristics (5) Weld position and direction of welding (6) Time lapse between passes

(7) Cleaning process and preparation of surface of steel before application of coating. (8) Specifications of all lining and sheathing materials, their thickness and application procedures.

4.3 The Contractor shall not change any details of manufacture procedure without

the approval of the Engineer. 5. Fittings 5.1 Fittings shall be fabricated from pipe conforming with the requirements of

this Specification. In addition between 5% and 10% of all welds shall be radiographed and the exposed film made available for inspection by the Engineer. Where considered necessary the Engineer may require additional radiographic tests and hydraulic tests may also be required on all flanged fittings or fittings on which doubtful weld inspection results are revealed.

5.2 Prior to the commencement of fabrication of fittings the Contractor shall

submit detailed drawings of the fittings and shall obtain the approval of the Engineer to his proposals. Overall dimensions of the fittings shall be as indicated on the Drawings attached to the Bills of Quantities or otherwise as given in British Standard 534.

6. Pipe Ends

6.1 Unless stated otherwise in the Bills of Quantities the pipes shall be supplied

with unbevelled plain ends in accordance with Section 7 Clause 7.4 of A.P.I. Standard 5 LS or the relevant clause of the adopted Standard suitable for use with Dresser Viking Johnson or similar couplings and shall be sufficiently free from indentations, projections or roll marks for a minimum distance of 150 mm from all plain ends to permit a tight joint make-up with the rubber gasket type of coupling.

6.2 If so stated in the Bills of Quantities but not otherwise the ends of pipes to be

coupled with mechanical couplings shall have a steel plate 75 mm x 50 mm x 10 mm thick welded to them before the application of the internal lining. These plates shall be supplied a clear 150 mm from the pipe ends to ensure


that no interference is caused to the jointing operation. The plates shall be welded to the pipes so that they lay on the same longitudinal line on the pipe.

6.3 If required the Contractor shall provide in accordance with the Provisional

items included in the Bills of Quantities similar 75 mm x 50 mm x 10 mm thick steel plates for site welding to the plain ends of pipes and fittings.

7. Flanges 7.1 Flanges shall be suitable for the nominal pressure stated in the Bills of

Quantities as follows. NP 10 for a nominal hydraulic working pressure of up to 10 kgf/cm2 NP 16 for a nominal hydraulic working pressure of up to 16 kgf/cm2 Dimensions of flanges shall be in accordance with BS 4504 : 1969 7.2 All bolts to be supplied with flanges shall be of ductile iron or high tensile

steel to the approval of the Engineer. 7.3 All gaskets shall be of the "inside bolt circle" type manufactured from Class

`A' natural rubber in accordance with the requirement of British Standard Specification BS 2494.

7.4 Two washers shall be supplied with each bolt and nut. 8. Tolerances 8.1 Paragraphs headed "Pipe Ends" and "Out of Roundness" in Table 6.3 of the

A.P.I. Standard shall be deleted and replaced by the following paragraph: 8.2 Pipe Ends Pipe 250 mm and smaller shall not be more than 0.40 mm smaller than the

specified outside diameter for a distance of 100 mm from the end of the pipe and shall permit the passage over the ends for a distance of 100 mm of a ring gauge which has a bore 1.6 mm larger than the specified out side diameter of the pipe. Pipe 300 mm to 500 mm inclusive shall not be more than 1.6 mm smaller than the specified outside diameter for a distance of 150 mm from the end of the pipe and shall permit passage over the ends for a distance of 150 mm of a ring gauge which has a bore 1.6 mm larger than the specified outside diameter of the pipe. At the option of the Contractor the minimum outside diameter of pipes 500 mm and smaller may be measured with a diameter tape. Pipe 550 mm and larger shall not be more than 1.6 mm larger than the specified outside diameter for a distance of 150 mm from the end of the pipe as measured with a diameter tape.


8.3 Out-of-Roundness For a distance of 150 mm from the ends of the pipe the maximum outside

diameter shall not be more than 1 per cent larger than specified and the minimum outside diameter shall not be more than 1 per cent smaller than specified.

8.4 Pipes supplied sized over their entire length within the above tolerance shall

be suitably marked for identification purposes. 9. Pipe Lengths 9.1 The average length of pipe in 90% of the entire consignment shall be 8 metres

and none of these pipes shall be shorter than 6 metres or longer than 10 meters.

9.2 The average length of pipe in 10% of the entire consignment shall be 4 metres and none of these pipes shall be shorter than 3.5 metres or longer than 4.5 metres. 9.3 Pipes for crossings shall be of the exact lengths stated in the Bills of Quantities + 50 mm.

10. Inspection and Testing 10.1 The Contractor shall obtain such facilities for inspection by the Engineer as

would be his as purchaser under the relevant A.P.I. Standard and he shall arrange for the Engineer to be supplied with a copy of the reports called for in the relevant Standard. The Contractor shall dispatch to the Engineer all films or records of inspection immediately after processing and in no case more than 24 hours after the inspection.

10.2 The Bill Inspection Hydrostatic Test Pressures shall be not less than those

stated in the Bills of Quantities. 11. Bitumen (Asphalt) Lining, Coating and Sheathing 11.1 All pipes shall be protected internally and externally in accordance with this

Specification. The term "lining": describes the coating of the internal surfaces. The term "coating" is used to denote an unreinforced coating applied to external surfaces and the term "sheathing" is used to denote a reinforced coating applied to external surfaces.

11.2 Tenderers shall use bitumen (asphalt) lining and sheathing. 11.3 The enamel shall be the same for lining and coating or sheathing.


11.4 All kettles shall be equipped with an efficient thermometer and adequate screens to prevent particles of foreign matter or other deleterious materials from appearing on the finished lining.

11.5 All materials rejected by the Engineer by reason of prolonged heating, over heating charring, contamination etc. shall be dumped and on no circumstances reheated for re-use.

11.6 At all times during cold weather when the pipe temperature is below 8oC or

during rainy or foggy weather when moisture tends to collect on cold pipe enamelling shall be preceeded by warming the pipe. Warming shall be done by any method which will heat the pipe uniformly to the recommended temperature without injury to the primer. Steel temperature of the pipes shall not exceed 70oC.

12. Preparation of Steel Surfaces 12.1 Immediately prior to the application of coating materials the surface of the

steel, shall be completely dry and free from contamination by oil, grease, dirt or other deleterious matter.

12.2 The method used by the Contractor to prepare the surface of the steel and the

degree of cleanliness and roughness of the surface shall be subject to the approval of the Engineer.

12.3 If necessary, the pipes shall be cleaned of oil, grease or wax by means of

immersion in a bath of 10% by wt. solution of sodium hydroxide at a temperature at least 50oC or other method approved by the Engineer.

12.4 Steel surfaces shall preferably be blast cleaned. The quality of surface finish

or blasted cleaned surfaces shall be not less than "Second quality" as defined in British Standard Specification BS 4232 : 1967, equivalent to Swedish Standard SA 2.5.

13. Priming 13.1 Immediately following the preparation of the steel surfaces, primers shall be

applied to the pipes and fittings in accordance with the requirements of AWWA Standard 0203-66.

13.2 All primers shall have good spraying and brushing properties and a minimum

tendency to produce bubbles during application. The primer shall dry hard to the touch when applied as recommended.

13.3 Primers shall produce an effective bond between the metal the subsequent

coating of enamel. They shall contain no benzol or other toxic or highly volatile solvents and no added pigments or inert fillers, or other substances and shall show no tendency to settle out in the container.

13.4 The primer shall be thoroughly agitated in the drums before use and care shall

be taken to ensure that loss of the volatile portions of the primer has not


caused thickening and that the primer is not contaminated by water, dirt or any other substances. Any primer so deteriorated or contaminated shall not be used.

13.5 Primers shall be cold applied in accordance with Clause 9.14 or may be hot

applied. 13.6 Other methods of obtaining an effective bond between the metal and coating

of enamel without the use of a primer, including pre-heating the pipe, shall be subject to the approval of the Engineer.

14. Primer under Bitumen (Asphalt) Enamel Coating and Sheathing 14.1 Primer to be used under bitumen (asphalt) enamel pipe coating and sheathing

shall be composed of a petroleum bitumen (asphalt) base and petroleum solvents suitably blended to produce a liquid coating which may be applied cold by brushing or spraying and shall be that recommended by the suppliers of the bitumen (asphalt) enamel specified in Clause 9.16.

15. Enamels 15.1 Bitumen (asphalt) enamel shall be specified in Clause 9.16. Alternatively for

the lining only an unfilled bitumen enamel to the approval of the Engineer may be used.

15.2 The enamel shall be such that it does not impart either taste or toxic

substances to chlorinated drinking water. 16. Bitumen (Asphalt) Enamel 16.1 Bitumen (asphalt) enamel shall consist of either bitumen derived from

petroleum or naturally occurring asphalt or a uniform blend of the two materials combined with an inert mineral filler which shall have a minimum tendency to settle in a fluid state. The enamel shall be uniform in character free from water and shall not foam when heated to 205oC,. The filler used shall be ground slate flour or talc. Limestone or asbestos filler shall not be used except with the prior approval of the Engineer. The enamel shall conform with the physical specification given in Table 1.


Table 1 Physical Specification of Bitumen (Asphalt) Enamel -------------------------------------------------------------------------------------------------- Properties Test Requirements Method Min. Max. -------------------------------------------------------------------------------------------------- Softening Point (ring and ball) ASTM D36 115oC 130oC Filler (ash) ASTM D271 25% 35% Filler fineness, through 200 mesh ASTM D546 90% - Specific gravity at 25oC ASTM D71 1.20 1.40 Penetration:25oC 100 g. 5 Sec. ASTM D5 8 15 Flash Point (Cleveland open cup) ASTM D92 200oC - Loss on heating at, 163o : 5hrs. ASTM D6 - 0.5% Settlement (ratio of ash in bottom half to ash in top half after 5 hours at 200oC) - - 2.1 Water content, by weight BS 3235 - 0.05% Sag after 24 hours at 75oC BS 4147 or AWWA 1.6 mm C.203 Cracking after 6 hours at -18oC AWWA C. 203 - None Peel test AWWA C. 203 No peeling ----------------------------------------------------------------------------------------------------- 17. Testing Primers and Enamels

i. The test procedure for primers and enamels shall be as set out in Table 1. If required by the Engineer the Contractor shall submit samples (not less than 20 kgs. of enamel and 2.5 litres of primer) for testing and approval before use.


18. Bitumen (Asphalt) Internal Lining 18.1 Except as otherwise provided herein the inside lining enamel shall be bitumen

(asphalt) enamel. 18.2 The Contractor shall ensure that the internal surfaces of the pipe are clean, dry

and free of dust before the application of the lining. 18.3 The application of the enamel to the inside surface of all pipes other than

fittings shall be by centrifugal casting by either the Trough Method or by the Retracting Weir of Food line Method.

18.4 The temperature of the enamel on application shall be as recommended by the

Supplier of the enamel and the Contractor shall provide the Engineer with a copy of the Supplier's instructions and recommendations for the application of the enamel. Care shall be taken to ensure that it is at no time heated above the maximum temperature recommended. In the event of the enamel being subjected to a temperature above that recommended it shall not be used but shall be discarded.

18.5 During application of enamel the pipe shall be revolved at the speed best

suited to produce a smooth glossy lining of uniform thickness. Finished enamel lining shall be free from wrinkles, sags, blisters or blow holes.

18.6 The thickness of the lining shall be 2.4 mm and allowable variations in

thickness shall not be out side the range 2 to 4 mm except within, 25 mm of the longitudinal weld where the allowable maximum thickness will be 5 mm.

18.7 All pieces of lined pipe in which excessive rough areas appear or other

irregularities exist which the Engineer considered unsatisfactory shall be stripped of the entire lining and relined.

18.8 The lining shall be carried up to the end of the pipe where a cut off of

approximately 45o shall be cleanly made while the enamel is plastic. 19. Bitumen (Asphalt) Sheathing 19.1 The Contractor shall ensure that the pipe is clean, dry and free of dust before

the application of the first flood coat of bitumen (asphalt) enamel. This shall be applied as soon as possible after the priming coat is dry and in any case before the primer has gone `dead'. In the event of the primer having gone `dead' the Contractor shall strip the dead primer and then re-prime the pipe.

The Contractor shall apply the first flood coat of enamel and while the

enamel is still hot the pipe shall be wrapped with fibre glass inner wrap. This shall be wound on with enough tension to ensure that it is fully saturated but care shall be taken to avoid pulling it through the enamel to the metal. The overlap of the inner wrap shall not be less than 25 mm and the thickness of the first coat shall be 2.4 mm with an allowable tolerance of + 0.8 mm.


19.2 The pipe shall then receive a second flood coat of enamel and whilst this is still hot shall be wound with outer wrap. Alternatively, the second coat of enamel may be applied simultaneously with the outer wrap. The overlap of the outer wrap shall be 25 mm and the thickness of the second coat shall be not less than 0.8 mm.

19.3 The total thickness of the sheathing shall in no place be less than 2.4 mm. 19.4 The sheathing shall be terminated cleanly at a distance of 150 mm from the

ends of the pipes and fittings or such other distance as required to be compatible with the dimensions of the couplings and moulding boxes.

19.5 After sheathing the outer surface shall be given a coat of water resistant

whitewash as specified in Clause 9.22. 20. Sheathing Reinforcement

20.1 Inner Wrap

20.1.1 The inner wrap shall be a glass fibre tissue which shall consist of a uniformly porous mat of chemically resistant bore-silicate glass containing not less than 5% B 203 as defined by ASTM definition C162-52.

20.1.2 The glass fibre monofilaments making up the mat shall be in a random

arrangement bonded with a phenolic type resin compatible with bitumen (asphalt) Enamel. Continuous filament glass yarn to provide longitudinal reinforcement shall be embedded in the mat at 20 mm centres.

20.1.3 The glass fibre base shall have the physical characteristics shown in

Table3. Table 3 - Physical Characteristics of Glass Fibre Base

Nominal Thickness Tensile Strength (per 150 mm wide strip) Porosity Temperature Resistance Phenolic Type Binder Content

0.5 mm 45 kg minimum 1.3 mm W.G. Unaffected under load in hot bitumen at 288oC for 1 minute 12% + 2%

20.1.3.1 Alternatively a woven glass fibre mat to the approval of the Engineer may

be used for the inner wrap. The composition of the fibre monofilaments and physical and chemical characteristics of the woven mat shall be similar to those specified for the glass fibre tissue and be in accordance with Section A.2.2 of AWWA Standard 0203-66.


20.2 Outer Wrap 20.2.1 The outer wrap shall consist of a glass tissue or mat as specified in clause

23.1 saturated with plasticised bitumen (asphalt) enamel. The resultant outer wrap shall be uniform flexible and with random pin holes to facilitate the release of hot gases.

20.2.2 The finished outer wrap shall have the physical properties shown in Table

4. Table 4 - Physical Characteristics of Outer Wrap

Thickness (nominal) Weight per 10 sq.m Tensile strength (per 150 mm wide strip) Tear strength (transverse)

0.75 mm 4.5 kg 54.5 kg minimum 4.5 kg minimum

20.2.3 The glass fibre base shall be saturated with bitumen (asphalt) compound

having the physical characteristics as given in Table 5 and which shall be fully compatible with the bitumen (asphalt) enamel specified for the pipe line coating.

Table 5 - Physical Characteristics of Bitumen Saturant

Test

Min Max

Softening Point-Ring &

Ball, ASTM D36-26 Penetration - 25oC -100 g per 5 Sec. - ASTM D5-52

80oC

15

85oC

25

20.2.4 Subject to the approval of the Engineer the Contractor may draw the glass

fibre tissue or woven mat through a bath of bitumen (asphalt) saturant, immediately prior to the application of the outer wrap to the pipe.

20.2.5 The Contractor may if he wishes and with the prior approval of the

Engineer use an outer wrap consisting of an asbestos felt base conforming to AWWA standard 0203-66 Section A2.1 saturated with bitumen (asphalt) as specified in sub-clause 20.2.3 hereof.

21. Coating Of Fittings 21.1 Fittings shall be cleaned, primed and coated to give results which are

equivalent to similar work on straight pipe sections. If the shape precludes spinning internal surfaces shall be double coated by application of enamel


with hand daubers. The brush strokes of enamel shall be made in the direction of flow. All brush strokes shall overlap to form a continuous coating.

22. Whitewash 22.1 The whitewash finish applied to the sheathing shall be of the following

composition. Water 200 litres Boiled Linseed oil 4 litres Processed quicklime 72 kg Salt (sodium chloride) 4.8 kg 22.2 Lime and oil shall be slowly added simultaneously to the water and mixed

thoroughly. The mixture shall be allowed to stand for not less than 3 days before it is used.

22.3 For the purpose of distinguishing between pipe type coloured pigment shall

be added to the whitewash as follows. Pipes sizes overall - light green In the case of unsheathed pipes a light green band shall be painted

longitudinally for the full length of pipes supplied sized overall. 23. Pipes to be laid above ground 23.1 Pipes for river over crossings and fittings to be laid above ground shall be

supplied lined as specified in Clause 9.18 hereof and with an external shop coat of type B (fast drying) primer as specified in Clause 9.14.1 or other primer approved by the Engineer which is compatible with the material to be subsequently used for painting.

24. Inspection and acceptance 24.1 The Contractor shall provide facilities and equipment as required by the

Engineer to test the interior and exterior coating of all pipes for holidays and any defects so revealed shall be made good in a manner approved by the Engineer. Voltages applied shall be not less than 8000 V in the case of the lining and 12000 V in the case of the sheathing.

24.2 Should the coating of any pipes exhibit six or more faults as revealed in

holiday detection the coating is to be stripped and the pipe recoated. 24.3 Repairs to the satisfaction of the Engineer will be allowed on these coatings

having between one and five faults. 24.4 Where up to four holidays occur within a single area of 400 sq.mm these four

holidays are to be taken as a single fault.


24.5 The Contractor shall provide facilities for the Engineer to carry out an adhesion test on the coating of up to 5% of the pipes. The adhesion test on the pipes shall follow the procedure for carrying out a peel test on test plates as described under Section 244 (5) in AWWA Std. C 203-66. The adhesion of the enamel coating shall be such that no peeling of the coating results from such tests. The coating shall be made good to the satisfaction of the Engineer after completion of adhesion tests. The adhesion test will be carried out over a temperature range consistent with the temperature of service conditions.

24.6 The Engineer shall have full access to all those parts of the plant that are

concerned with the testing, furnishing or preparation of materials or the performance and testing of work under this specification.

24.7 The Contractor shall furnish the Engineer with reasonable facilities and space

(without charge) for the inspection, testing and obtaining of such information as he desires respecting the character of material in use and the progress and manner of the work.

25. Mechanical Couplings and Flanged Adaptors 25.1 Mechanical couplings for jointing plain-ended pipes shall be of the Dresser

Viking Johnson or similar type approved by the Engineer. 25.2 The thickness of the steel in both the middle ring (sleeve) and the follower

rings (flanges) shall be not less than 1.6 mm thicker than the thickness of the walls of the adjoining pipes. The middle ring (sleeve) and the follower rings (flanges) shall be of such materials and dimensions that they are not stressed beyond half the yield stress of the material when the pipes connected by them are subjected to the hydrostatic test pressure stated in the Bills of Quantities.

25.3 Except where otherwise stated the middle ring (sleeve) of the coupling shall

be provided with a suitable pipe stop (centre register). 25.4 The joint rings used shall be of Class `A' natural rubber in accordance with

the requirements of British Standard Specification B.S. 2494 or other Specifications approved by the Engineer.

25.5 Flanged adaptors for jointing flanged fittings to plain ended pipes shall

conform to the foregoing contents of this Clause. 25.6 Prior to the commencement of fabrication the Contractor shall submit to the

Engineer for approval detailed drawings of all mechanical couplings and flanged adaptors.

25.7 All mechanical couplings and flanged adaptors shall be supplied with a shop

coat of Type B (fast drying) primer as specified in Clause 9.14.1 or other primer approved by the Engineer which is compatible with the material to be subsequently used for moulding or painting.


25.8 Moulding boxes for moulding mechanical couplings shall be of cast aluminium alloy to the approval of the Engineer. They shall be of economical design sized so that the minimum clearance over any part of the coupling shall be 6 mm and also make a close fit over the external surface of the pipe sheathing and steel pad specified in Clause 9.6.2

26. Marking 26.1 The contractor shall label and clearly mark all pipes, fittings crates and boxes

in indelible paint specified in the notes forming a part of this Specification. 26.2 All lettering and numbering shall be at least 50 mm high. 26.3 In addition all fittings shall be marked with the corresponding item number in

the Bills of Quantities or other number specified by the Engineer. 27. Protection of Ends 27.1 The Contractor shall provide protection to the approval of the Engineer for the

ends of all pipes and fittings prior to the pipes and fittings leaving the manufacturers works in order to guard effectively against damage during transit and storage and the ingress of foreign matter inside the pipes and fittings. Suitable ventilation openings shall be incorporated in all end caps.

27.2 All details of the proposed methods of providing such protection shall be

submitted at the time of tendering. 28. Storing Handling and Hauling of Pipes and Fittings 28.1 Every precaution shall be taken to avoid damage to pipes and fittings. The

pipes shall not be stacked more than three tiers high. 28.2 In handling pipes and fittings every care should be taken to avoid distortion,

flattening denting scoring or other damage. Pipes and fittings shall not be allowed to drop or strike objects and shall be lifted or lowered from one level to another by means of approved equipment only.

28.3 When lifting pipes and fittings special lifting hooks with a curved plate to fit the curvature of the pipes or fittings shall be used. Alternatively, Webbing slings not less than 300 mm wide or other approved means shall be used. Pillows shall also be provided between securing chains or lashings when loads are being transported.

28.4 Lined and sheathed pipes and fittings shall not be handled or transported

when the ambient temperature is below 5oC unless the manufacturer of the enamel indicates otherwise.


29. Protection and Moulding of Couplings 29.1 All couplings will be protected externally after assembling with bituminous

composition poured into moulds. The ends of each pipe and the inside of each coupling will be protected by coating with bituminous paste before assembly.

29.2 The Contractor shall supply all the necessary bituminous composition and

paste required for this work and he shall include the details in the appropriate items of the Bills of Quantities.

29.3 All buried joint made with Johnson Flange Adaptors of flanges will be

protected externally after assembly with `Denso' paste, mastic and tape wrap manufactured by Messrs. Winn & Coales or equally suitable materials to the approval of the Engineer. The paste mastic and wrapping materials shall be suitable for application in wet conditions.

The contractor shall supply all the necessary materials and shall give details

of those proposed in the appropriate items in the Schedule of Particulars and Bills of Quantities.

30. Packing of Bolts, Joint Rings and Gaskets 30.1 Bolts of the same length and size (and their accompanying nuts and washers)

shall be packed together in boxes not exceeding 100 kg gross weight. 30.2 Joint rings and gaskets shall be packed in boxes and separate packages shall

be provided for each size and description of ring or gasket. 30.3 Each box and package therein shall be clearly labelled stating the number,

size and description of the contents. 31. Couplings Stools and Pipe Saddles 31.1 The Contractor shall supply coupling stools and pipe saddles for the support

of pipe above ground. The coupling shall be manufactured generally in accordance with the drawings shows in the appendices and shall where appropriate conform with the Specification Clauses relating to mechanical couplings and flanged adaptors.

31.2 Prior to the commencement of fabrication the contractor shall submit to the

Engineer for approval detailed drawings of the coupling stools and pipe saddles required.

31.3 All couplings and saddles shall be supplied with a shop coat of Type B (fast

drying) primes as specified in Clause 9.14.1 or other primer approved by the Engineer which is compatible with the material to be subsequently used for painting.


32. Pipes Restraining Bar 32.1 The Contractor shall supply pipe restraining bars for side welding or

otherwise to pipes laid at steep gradients over ground as indicated in Appendix.

32.2 The method of fixing the bars shall be such that the internal lining of the pipe

shall not be damaged. Where greater thickness of pipe wall is required to prevent damage to the lining by welding heat, the number of pipes requiring restraining bars shall have pads welded on at the time of fabrication for later fixing of the bars on site.

32.3 Prior to commencement of fabrication of the bars the Contractor shall submit

detailed drawings to the Engineer for approval. 32.4 All bars shall be supplied with a shop coat of Type B (fast drying) primer as

specified in Clause 9.14.1 or other primer approved by the Engineer which is compatible with the material to be subsequently used for painting.

33. Cement-Mortar Lining and Coating of Steel Pipes 33.1 As an alternative, the tenderers are requested to quote for cement-mortar lined

and coated steel pipes. 33.2 Cement-Mortar lining and coating of steel pipes shall be according to

AWWA Standard C 205 - 71 for Cement - Mortar protective lining and coating for steel Water Pipes - 4 in and Larger Shop applied or any other equivalent standards acceptable to the Engineer as providing equivalent or better quality of materials and workmanship.

33.3 The length of lining and coating hold back are the same as those specified for

Bitumen (asphalt) lining, coating and sheathing in this section. 33.4 Wire fabric reinforcement shall be used for lining specials. 33.5 Thicknesses of lining and coating and the respective tolerances shall be those

given in Table 1 and 2 of AWWA Standard C 205 - 71. 33.6 Spiral Wire reinforcement shall be used for mortar coating of pipes. 33.7 Dielectric under coat will not be necessary for coating of the pipes. 33.8 The Bidder shall state the type of curing he proposes to adopt.

♦ SPECIAL SPECIFICATIONS FOR TIMBER


♦ SPECIAL SPECIFICATIONS FOR TIMBER 1 Timber Unless otherwise specified in the respective items of the BOQ, the timber for all trades shall be

as follows: 1.1 Door, Window and Fanlight Frames Category A: 1. Jak 2. Satin 3. Palu 4. Milla 5. Local Teak 6. Halmilla 7. Wewarana 8. Hulanhik Category B: 1. Kohomba 2. Palu 3. Kumbuk 1.2 Door, Window and Fanlight Sashes, Cupboards, Counters and Shelving: Category A: 1. Jak 2. Satin 3. Mahogany 4. Sooriya Mara 5. Halmilla 6. Wewarana 7. Hulanhik 8. Local Teak Category B: 1. Ranai 2. Kohomba 3. Valdel 1.3 Roof Framework Category A: 1. Jak 2. Wewarana 3. Milla 4. Palu 5. Madan 6. Mee Category B: 1. Etathimbiri 2. Batadomba 3. Dun 4. Alubo 5. Liyan 6. Yellow Balaw 7. Kon 8. Kolon 9. Domba 10.Karaw 11.Ketakalal 12.Uberiya 13.Kohomba 14.Valdel 1.4 Ceiling Framework Category A: 1. Jak 2. Wewarana 3. Milla 4. Palu 5. Madan 6. Mee 7. Local Teak 8. Hulanhik Category B: 1. Etathimbiri 2. Batadomba 3. Dun 4. Alubo 5. Liyan 6. Yellow Balaw 7. Kon 8. Kolon 9. Domba 10.Karaw 11.Ketakalal 12.Uberiya 13.Kohomba 14.Valdel 15.Ranai 1.5 Valance Board and Valley Boarding & Barge Board Category A: 1. Jak 2. Mahogany 3. Wewarana 4. Hulanhik 5. Sooriya Mara Category B: 1. Kolon 2. Ginisapu 3. Valdel 4. Kohomba 5. Yellow Balaw

SPECIFICATION FOR TRENCH EXCAVATION, BACKFILLING AND

ROAD REINSTATEMENT FOR PIPE LAYING


Specification for Trench Excavation, Backfilling and Road Reinstatement for Pipe Laying

1. Pipe Trench Excavation - General Trench excavation means excavation in all materials of whatever nature encountered

for trenches into which pipes are to be laid or pipe appurtenances constructed. Pipe shall mean pipe of all kinds and for whatever purposes.

The contractor would be required to provide shoring for the trenches in order to minimize damage to the roads and also other utilities. If the Contractor is required to excavate a trench, wider than the maximum trenches width, prior approval of the Engineer should be obtained. However, the contractor shall bear the total responsibility for damages to utilities, backfilling and compaction of the trench as per specifications and reinstatement of roads occurred as a results of collapse of side of the trench. Road reinstatement both temporary and permanent shall be measured in linear meters along the top surface of trenches for different diameters of pipes.

Disruption to traffic should be minimized. The Contractor should provide necessary measures for the safety of pedestrians, vehicles etc. All open trenches and backfilled areas should be protected by providing proper barricading, night lighting and also steel plates etc. when necessary. Road signs at either ends of the road warning motorists and pedestrians should be erected. Any damage to vehicles or injured to public and the damage to third party property due to the above excavation work or during movement of machinery should be the responsibility of the Contractor. It may be necessary to transport the excavated material temporarily to other locations. Required traffic control arrangements in concurrence with the traffic police and Local Authority should also be provided by the Contractor.

Contractor shall take every precautions to minimize damages to third party property due to excavation and backfilling of pipe trenches. Any damages to third party property shall be rectified and made to the good condition at the contractor’s cost. Trenches shall be carried out manually if excavation using machinery poses a potential danger to the roads and third party property including other utilities. The trench shall be excavated to required depth and trimmed the bottom to specified gradient as shown in the drawings. Any excessive excavation shall be filled and compacted by the contractor at his own cost as directed by the Engineer.

Asphalt cutters should be used when damaging asphalt concrete and concrete paved roads. Prior to the commencement of pipe laying as far as practicable, Engineer shall nominate a soil testing laboratory and inspected the pipeline trace jointly with the Contractor to decide on the suitability of the materials to be excavated for backfilling of the trenches.

Engineer along with the soil laboratory personnel will decide on the locations where the soil tests are to be carried out to determine the soil parameters setout in Clause 2(v) and details given in the drawing Nos. WT 301/BT/01 & WT 301/BT/02 and

Revised on 14-02-2012


decide on the suitability of the excavated material for backfilling based on the test results and recommendations of the soil laboratory personnel. If the excavated soil is found to be unsuitable, Engineer shall inform the Contractor of the sections of the pipeline trace to be backfilled with imported soil from the approved borrow pits.

2. Trench Alignment and Grade Before starting excavation in any road the Contractor shall have obtained the approval

of the Engineer and Engineer shall obtain the approval of the relevant Road Authority for Contractor’s detailed work programme for the trench excavation in roads ahead of the particular work. This programme shall contain the names of the roads and chainages to be excavated, date of commencement and planned completion date of backfilling, planned dates of completion of temporary and permanent road reinstatement, and the dates of handing over to the relevant Road Authority. No excavation shall be permitted unless the Contractor shall have obtained approval of the said programme as aforesaid and can demonstrate that all necessary pipes fittings materials and plant are available on site for the speedy completion of all the work.

i Construction Alignment and Grade The line and level of trenches shall be as shown on the Drawings or as

determined from the Drawings or as may be directed by the Engineer. Before commencing trench excavations, the route of the trench shall be pegged out accurately and the natural ground levels shall be agreed with the Engineer. Strong sight rails shall then be fixed and maintained at each change of gradient, and at as many intermediate points as may be necessary. On these rails shall be marked the centre line and the level to which the excavation is to be carried out, such rails being not more than 50 m. apart and at changes of direction and grade.

ii. Changes in Line and Grade

In the event obstructions not shown on the plans are encountered during the progress of the work which will require alternations to the plans, the Engineer shall have the authority to change the plans and order the necessary deviation from the line and/or grade. The Contractor shall not make any deviation from the specified line and/or grade without approval by the Engineer. Should any deviations in line and/or grade be permitted by the Engineer in order to reduce the amount of rock excavation or for other similar convenience to the Contractor, any additional costs for thrust blocks, valves, air and vacuum assemblies, blow-off assemblies, extra pipe footage, manholes or other appurtenances shall be borne by the Contractor. The Contractor shall include in his unit rates in the contract provision to cover any deviation from the invert grade shown on the plans to facilitate extra depth required to eliminate possible conflicts between culverts and other utilities.



iii. Trench widths

Trench excavation shall be carried out by such methods and to such lines, dimensions and depths as shall allow for the proper construction of the works, provided always that, unless the Engineer permits otherwise, for trench excavation, the Table 1, shall be referred for nominal trench widths and depths. Any changes to Table 1, if necessary depending on the special conditions shall be authorized by the Engineer. Trenches shall have vertical sides or battered trench as specified herein unless otherwise authorized by the Engineer. Notwithstanding the foregoing, any rock in trench excavation shall be so excavated that the clearance between the pipe when laid and the rock sides and bottom of the trench is kept to the minimum limits necessary to provide for the specified thickness of bedding and concrete protection of the pipe. Bell holes and holes and depressions for couplings, valves and the like shall be excavated the same distance below these installations.

iv. Working Space

Excavation for structures such as valve chambers etc. shall be allowed 30 cm working space for purposes of establishing Contractor’s liability for permanent reinstatement costs.

v. Backfill Material

Soils used as backfilling material shall be naturally occurring soils and shall not be highly plastic clays, silts, peat of other organic soils or any soil that is mixed or contaminated with the top soil, vegetation and other deleterious matter. Material used for backfilling shall conform to the requirement of Type 1 materials as given below. Type 1 material shall be soil having the maximum dry density under standard conditions of proctor compaction not less than 1600 Kg/m3 with the properties plastic limit <15, liquid limit (LL) < 40, CBR >20. Materials excavated from the trenches may be used as backfill provided it meets the requirements specified for backfill material. Surplus materials from excavations shall be removed and disposed of by the Contractor as required by the Engineer and as specified on contractors cost. The trench shall be dug only so far in advance of pipe laying as the Engineer shall permit. Where in the opinion of the Engineer sufficient supplies of the aforesaid material for trench refilling cannot reasonably be obtained from excavations, the Engineer may order the Contractor to carryout following.


a) Remove Stones

To carry out such work as may be necessary to sieve out stones, from the excavated material at contractors cost.

b) Borrow

If the excavated soil from trench is not satisfy the requirements, imported soil to be used for backfilling of trench. The Contractor shall take every steps to excavate suitable material from borrow areas and transport it to the length of trench to be backfilled, and the Contractor shall do any or all of these things as directed and as specified in the drawings and the specifications with own cost.

TABLE 1. DETAILS OF TRENCH WIDTH AND DEPTH UPTO THE INVERT FOR THE PIPE LAYING (Minimum Recommended)

PE Pipes DI Pipes

Dia. (mm)

Trench Width

(m) depth (m)

80 0.60 0.95 100 0.60 0.95 150 0.60 1.00 200 0.60 1.20 250 0.60 1.25 300 0.60 1.30 350 0.75 1.35 400 0.90 1.40 450 0.90 1.45 500 0.90 1.50 600 1.10 1.60 700 1.20 1.70 800 1.30 1.90 900 1.50 2.00

1000 1.60 2.10 1100 1.70 2.25 1200 1.80 2.40 1400 2.00 2.60

Dia. (mm)

Trench Width

(m) depth (m)

90 0.30 1.00 110 0.40 1.12 125 0.40 1.14 140 0.40 1.15 160 0.45 1.17 180 0.45 1.19 200 0.45 1.21 225 0.50 1.24 250 0.50 1.26 280 0.60 1.29 315 0.60 1.33 355 0.70 1.37 400 0.70 1.41 450 0.70 1.46 500 0.75 1.51 560 0.90 1.64 630 0.90 1.64


PVC Pipes

Note :- Thickness of bedding is excluded. 3. Trial Holes Trial holes shall be excavated well ahead of the trench excavation to such depths as

necessary to determine and confirm the alignment for the trench. Trial holes may also be required by the Contractor to determine the position of underground services, sub-soil drains or rock profile for any other reason. The Contractor shall obtain all necessary permissions from the Road Authorities for the excavation of trial holes. Trial holes shall be excavated at a distance of 50 m or as directed by the Engineer.

3.1 Reinstatement of Trial Holes

The Contractor shall arrange the refilling and reinstatement of trial holes to be carried out immediately after the required information is obtained. The reinstatement of the surfaces of trial holes shall be carried out to the approval of the Engineer and the relevant Roads Authority at the contractor’s cost.

4. Trench Excavation in Roads When excavating trenches along public roads, the Contractor shall comply with the

requirements and conditions of the relevant road maintenance authority having jurisdiction over the particular road, viz, the Road Development Authority (for major roads) the Provincial Road Development Authority (for secondary roads) for the Local Government Authorities (for minor roads).

The information provided regarding jurisdictions in the drawings titled ‘Key Plan –

Miscellaneous Information’ is only as a guide and not to be taken as the final status. The Contractor shall obtain the information regarding the final status from the relevant authorities.

All trench excavation and other work carried out within the limits of any public road

shall be completed as rapidly as possible and the Contractor shall make every effort to ensure that no more than half of the width of the carriageway shall be obstructed at one time. Road drains and kurbs shall be kept free from obstruction. The Engineer may direct that trench excavation in highways shall be located in footpaths or in

Dia. (mm)

Trench Width

(m) depth (m)

63 0.30 0.90

90 0.45 1.10

110 0.45 1.20

160 0.60 1.20

225 0.60 1.30

280 0.60 1.30

315 0.75 1.35


verges rather than in the carriageway. If that is the case, trench excavation shall wherever practicable be carried out in such a way that every part of the excavation is at least 1m clear of the existing edge of the carriageway. In any event the Contractor shall take special precautions, which shall include the continuous support of the sides of the excavation, from the time when excavation is begun until the refilling of the trench is completed, to ensure that there is no disturbance of the adjacent road or road foundation. Where excavated material has temporarily been deposited on an adjacent surface, the surface shall on completion of refilling be restored entirely to its original condition and left free of loose stones.

4.1 Excavation in carriageway

The excavation of trenches in RDA roads shall be in the shoulders as far as possible.

However, when excavations are needed within the carriageway, the Contractor shall take all the necessary care to minimize the area of damage to the road surface. Before starting excavation, the Contractor shall use asphalt cutting apparatus comprising a diamond disc or similar, to cut the surface of the carriageway along the intended line of excavation. Necessary shoring and road barricades, traffic diversion etc shall be provided by the Contractor.

4.2 Security requirements

The Contractor shall inform the relevant local police station regarding the excavation in public road at least one week prior to commencement.

4.3 Safety precautions

The Contractor shall erect and continuously maintain road signs and adequate lighting through out the night ahead of each end of excavation of trenches, warning about the excavation, until the temporary and Permanent reinstatement are completed. The road signs should be written in red luminous paint on white background so that they are visible at night to the vehicle drivers.

Safety precautions of workers and public shall always be taken during day time and also in night if night works are done. Contractor shall take all precautions to protect workers, public and third party property during or in the process of rock excavation. In case of rock blasting, all precautions specified in the safety guidelines or Manuals or any other acceptable Manuals to the Employer by the Department of Labour, Sri Lanka shall be strictly followed. Suitable blasting technique shall be selected. Any damages to workers, public, third party property shall be compensated by the contractor at his cost. Adequate protection shall be provided along the trench excavation to the approval of the Engineer. The excavated material shall not be deposited or dumped along the trench so that it will obstruct the movement of vehicles or pedestrians. If the Engineer or the Road Maintenance Authority directs so, Contractor shall remove the excavated material and store it elsewhere, until it is used for backfilling, at his own cost.


The Contractor shall maintain warning lights and barricades throughout the night at the road crossings until it is temporarily reinstated, or at the trench excavations if it has to be kept open overnight, or at any road excavation as directed by the Engineer.

The Contractor shall supply any reasonable materials and/or manpower necessary to maintain a smooth traffic flow as required and as directed by the Engineer.

4.4 Road Closure

The Contractor shall make every effort to avoid complete closure of the roads for traffic due to the Construction activities.

In any event that this is unavoidable, the Contractor shall obtain the approval of the Engineer to that effect, furnishing all the details of the work. Contractor shall also obtain the permission from the Road Maintenance Authority, Local Government Authorities (MC, UC, PS) the Local Police Station and any other relevant authority, and shall abide by their requirements. The Contractor shall allow in his work programme for any delays which may arise in obtaining such permissions.

Contractor shall obtain necessary Insurance coverage or any other means to compensate the loss of Revenue of the Third Party Business Men, Transport Agencies, Bus Services etc. contractor shall relieve the Employer from any claims what so ever arising out of the closure of road.

5. Trench Excavation in Surfaces Other than Roads

Trench excavation in surfaces other than roads shall include all surfaces except those asphalt surfaces which require road reinstatement. These surfaces include but are not limited to fields, paddy fields, pasture land and the like, footpaths, verges, non-asphalted roads, lanes, alleys, bund embankment and all public and private lands. Trench excavation located in fields shall, if the Engineer so requires, have temporary fencing erected around that length. Temporary fencing shall not normally be removed until the trench excavation has been refilled and reinstated. The Contractor is hereby notified that generally pipe alignments not in streets are covered with a vegetation growth which must be removed and disposed off the site of work. The Contractor shall have particular regard to the safety of livestock which may be in the area, and shall ensure that all open excavations, access routes and steep or loose slopes arising from the Contractor’s operations are adequately fenced and protected. After the erection of temporary fencing where required, the Contractor shall remove top soil to such depth and over such area as may be necessary to provide sufficient material to ensure adequate surface reinstatement of the working areas occupied by the Contractor for construction of the pipeline.

Excavation in Asphalt roads and concrete paved roads shall be done using Asphalt cutter and concrete cutter to avoid damages to other parts of the road. Contractor shall remove re-concrete and Asphalt parts of the excavated soil as directed by the Engineer at this own cost.


6. Temporary Buildings

Temporary buildings sites (squatters) may also occupy pipeline rights-of-way. The Employer will remove the occupants and the Contractor may demolish the buildings as directed by the Engineer. The Employer, under the laws of Sri Lanka, is not required to obtain easements or be liable for loss of business for construction of water pipelines and appurtenances. However, the Contractor is required to limit the damage to any existing improvement and to make full compensation for any damage done as a result of the construction activities.

7. Bedding Types and Special Protection

It should be ensured that the trench bed is leveled in conformity with the levels as indicated in the drawing. The pipe bedding material shall be well graded and free from organic matter. Excavated material also could be used if it satisfies the requirements laid down in the drawing and with the approval of the Engineer. The Contractor shall adopt the special bedding type A,B, C and D specified in the relevant type drawing where appropriate. When ground conditions requiring the use of special bedding types are encountered, the Contractor shall inform the Engineer, and with his approval, adopt the proper bedding type. The chainages indicate in the LS drawings for special bedding types, are only for guidance. Decision of the Engineer in this regard shall be final. The filling material shall be the soil having the maximum dry density under standard conditions of compaction not less than 1600 Kg/m3 with the properties PL<15 , LL<40 , CBR >20 and the particle sizes not greater than 25mm. The bedding material shall be Quarry dust, Mined sand or Crushed stone as specified in the relevant type drawing. When sand is used as bedding material, 100mm wide RCC grade 20 barriers at 50m intervals across the trench to cover full widths of the trench and full depth of the bedding shall be provided. The trench shall have special protection when the soil condition is unfavorable in such a way the bearing capacity is less than 75 KN/m2. The Geotextiles shall be used to bear the soil load above where it is specified in the type drawing (attached) or directed by the Engineer. The Table 2 given below shall be referred for the properties of Geotextiles. The Geotextiles shall be wholly synthetic and is tropic fibrous material. It shall have properties not inferior to those listed in Table 2.

When the minimum specified cover to the pipe line from the surface cannot be maintained due to some special reason, the Contractor shall adopt the special protection type using concrete pre-cast slabs as specified in the relevant type drawing and as instructed by the Engineer.


TABLE 2

Property Test Method Value Unit Tensile strength (wet and dry) under uniform applied stress

7500

N/m2

Grab tensile strength ASTM 1682 100m

660

N

Trapezoidal tear strength ASTM 117 300 N

CBR Puncture resistance DIN 54307E 1600 N

Burst Strength ASTM 3786 1400 KPA

Pore Size > 0.03 < 0.10

mm mm

Permeability to water under 100mm head

50

l/m2/sec

8. Supporting Trench Excavation

The Contractor shall effectively support the sides of all trench excavations which shall include the use of steel sheet piles where necessary to prevent any fall or sliding of the embankments or run from any portion of the ground outside the excavation into the trench and to prevent settlement of or damage to structures adjacent to the excavation. The Contractor shall be deemed to have made his own allowance for shoring up the sides of trenches, any extra excavation necessary to provide space for such support and for any other working space. If for any reason any portion of trench excavation shall give away, the Contractor shall at his own expense take all necessary remedial measures including the excavation and removal of all the ground thereby disturbed.

8.1 Battered Trench Sides Where the Contractor elects and is permitted by the Engineer to execute trench excavations with battered sides instead of providing support as aforesaid they shall be excavated to stable slopes and heights as a slope of not steeper than one to one from a point of 30 cm above the top of the pipe. The toe shall be set back not less than 30 cm from the vertical face of the trench.


9. Trimming Trench Excavation

When excavating to specified levels for trench excavation or to specified limits for the face of any structure therein required to about undisturbed ground, the Contractor shall not excavate the last 15 cm until the Engineer permits otherwise. Should the Contractor have excavated to within 15 cm above these specified levels or to within 15 cm of these specified limits before he is ready or able to commence the constructional work he shall where required by the Engineer excavate further so as to remove not less that 15 cm and any such further excavation and additional foundation material ordered by the Engineer shall be at the cost of the Contractor. The bottom of trench excavations shall be carefully boned in and trimmed true to grade with the aid of a straight edge at least 6 m long as to ensure a continuous support for the pipes. Any stones or flints either likely to cause the pipe to bed unevenly or to damage the pipe and its coating of greater than 15 mm in size shall be picked out of the trench bottom and any holes so formed shall be filled in with soft material and trimmed to the correct level. All shattered and loose material shall be removed from the bottom of the trench excavations so that the bedding material rests on a solid and clean foundation.

10. Inspection by Engineer

When the specified levels of trench excavation are reached the Engineer will inspect the ground exposed and if he considers that any part of the ground is by its nature unsuitable, he may direct the Contractor to excavate further and to refill the further excavation with such materials as he may direct. Should the bottom of any trench excavation while acceptable to the Engineer at the time of the inspection subsequently become unacceptable due to exposure to weather conditions or due to flooding or have become puddled, soft or loose during the progress of the works, the Contractor shall remove such damaged, softened or loosened material and excavate further by hand. In this case the cost of the extra excavation and of the additional foundation materials required will be the Contractor’s responsibility.

11. Disposing Material from Trench Excavation

Subject to any specific requirements of the Contract, the Contractor shall make his own arrangements for the temporary storage of any excavated material which is required for use in refilling trench excavations, including any necessary double handling. In this connection the Contractor shall have regard to the working areas available to him for the construction of the pipeline particularly where this is located in roads or in other places to which the public has free access. Any temporary tips alongside the trench excavations shall be to stable slopes and heights. Where the nature the excavated materials is suitable, the Contractor’s temporary storage as aforesaid shall include for separate storage as the Engineer may direct of any of the various grades of material hereinafter specified for the refilling and surface reinstatement of trench excavation, namely, soft material , coarse material, hard material and topsoil. Any excavated material not required for or not suitable for use as refilling as aforesaid or use elsewhere in the Works shall become the property of the Contractor and he shall be entirely responsible for its removal from the Site and for its ultimate disposal. Contractors are reminded that when working along the


carriageways it is often not possible to stack or place excavated materials along the trench and they may be required to remove such materials required for backfill to temporary sites to be provided by the Contractor and to return these materials on completion of pipe laying.

12. Trenches not to be Left Open

Trench excavation shall be carried out expeditiously and; subject to any specific requirements of the Contract, the refilling and surface reinstatement of trench excavations shall be commenced and completed as soon as reasonably practicable after the pipes have been laid and jointed. Pipe laying shall follow closely upon the progress of trench excavation, and the Contractor shall not permit more than 20 m of trench excavation ahead of pipe laying to remain open. The Contractor shall take precautions to prevent floatation of pipes in locations where open trench excavations may become flooded, and these precautions may include the partial refilling of the trench. If the Engineer considers that the Contractor is not complying with any of the foregoing requirements he may prohibit further trench excavation until he is satisfied with the progress of laying and testing of pipes and refilling of trench excavation. The Contractor shall not excavate trenches in more than one location in any one road at a given time without the Engineer’s permission.

13. Control of Water

All excavation and placement of backfill and fill shall be carried out in the dry. The Contractor shall furnish, install and operate all necessary machinery, appliances and equipment to keep excavations free from water during construction, and shall dewater and dispose of the water so as not to cause injury to public or private property, or to cause a nuisance or a menace to the public. He shall at all times have on hand sufficient pumping equipment, potable Generators and other machinery in good working condition for all ordinary emergencies, including power outage, and shall have available at all times competent workmen for the operation of the pumping equipment. During excavation, construction of pits, etc. installation of pipelines and fittings, placing of structure and trench backfill and the placing and setting of concrete, excavations shall be kept free of water. The Contractor shall control surface runoff so as to prevent entry or collection of water in excavations. The static water level shall be drawn down a minimum of one of foot below the bottom of the excavation so as to maintain the undisturbed state of the foundations soils and allow the placement of any fill or backfill. The dewatering system shall be installed and operated so that the ground water level outside the excavation is not reduced to the extent that would damage or endanger adjacent structure or property. i Submittals

Before dewatering is started the Contractor shall file for record purposes only with the Engineer the method, installation and details of the dewatering systems he proposes to use.

ii Release of Groundwater


The release of ground water to its static level shall be performed so as to maintain the undisturbed state of the natural foundation soils, prevent disturbance of compacted fill or backfill and prevent flotation or movement of structures, pipelines and sewers.

14. Backfilling Trench Excavations and Compaction

The backfilling material to be used shall be as specified above and indicated in drawings for type of pipes at different level in trench. Accordingly the backfill material which shall be used upto 300mm from the top of the pipe, or as indicating shall be a sandy material or quarry dust free of stones, hard objects etc. Excavated earth may be used for this purpose provided it meets the requirements and approved by the Engineer. For the remaining backfill excavated earth could be used if suitable. However the backfill material shall be free of particle size as specified in different level of layers in trench. If excavated material is not suitable the Contractor should bring specified material from outside. During wet condition, if the excavated material from the trench cannot be compacted to the required degree, the Contractor may be required to use imported materials as backfilling. However if the excavated material have been spoiled by the Contractor due to his negligence, the Contractor shall be required to use imported material as directed by the Engineer at his own cost. The standard compaction test shall be carried out as per test 12 of BS 1377 – 75 or ASTM D 698 – 98. The backfill material shall be placed in layers of 150mm thick and well compacted. Where necessary the Contractor shall adjust the moisture content of the fill material either by drying out or by adding water to assist the compaction of the materials. During the compaction the backfill shall have a uniform moisture content equal to or a little above the optimum moisture content recorded in the compaction test. Backfill shall be compacted to a dry density of not less than 98% [or as indicated in the relevant drawing at different layers in the trench] of the maximum dry density. Suitable approved mechanical rammers shall be used for compaction. The remainder of the refilling may consist of coarse material including broken rock from excavation not greater than 25mm, free and clods of earth larger than 15 cm in size and boulders of any size and shall satisfy the soil properties given in Clause 2(v) hereof provided that the compacted backfill is, in the opinion of the Engineer, sufficiently dense to prevent material from the superimposed layers being washed into the voids in such backfill. This coarse material shall be spread in layers of not greater depth than 20 cm and be thoroughly rammed by an approved mechanical rammer.

The coarse filling is to be carried up to the surface level existed before the commencement of the Works (in roads and footpaths) or (elsewhere) to such level as with the surface reinstatement. Hard material such as broken rock and original road metalling shall not be used for the reinstatement of road.


i. Compaction

Where necessary, the Contractor shall adjust the moisture content of the refill material either by drying out or by adding water to assist the compaction of the materials. During the compaction, the backfill shall have a uniform moisture content equal to or a little above the optimum moisture content recorded in the Compaction Test. Backfill shall be compacted to a dry density of not less than 98% of the Laboratory Proctor Density when tested in accordance with these specifications. The Contractor shall carry out a minimum of one compaction test each working day that back filling is taking place. The Contractor is advised to use clean sand or other clean granular material approved by the Engineer to obtain the required compaction in the presence of wet conditions, if the excavated materials or selected backfill materials cannot be compacted and the compaction work is held up.

The Contractor is advised to consider the cost of such materials in his rates. Sand backfilling shall only be laid on level areas and the sand water jetted to consolidate completely. When sand or clean granular materials are used, they shall be protected from washing away by capping with 150 mm of lateritic soil with proper moisture content compacted to 98%.

ii Miscellaneous

Should the material being placed as backfill, while acceptable at the time when approved, become unacceptable to the Engineer due to exposure to weather conditions or due to flooding or have become puddled, soft or segregated during the progress of works, the Contractor shall at his own expense remove such damaged, softened or segregated material and replace it with fresh approved material. To permit the proper consolidation of backfill into the voids behind trench sheeting and supports, trench sheeting shall be withdrawn gradually as backfill progresses in depth and along the trench. On no account shall any excavated material be dozed back when refilling trenches in roads and no backfilling shall be carried out unless in the opinion of the Engineer, sufficient mechanical rammers are in operation on that portion of the work. Where directed by the Engineer, trench excavations shall be refilled with concrete.

15. Road Reinstatement

Road reinstatement shall be done as stated in the drawing Nos. WT 301/BT/01 & WT 301/BT/02 and as specified in the ICTAD Specification No. SCA/5, Second Edition June 2009 for Construction and Maintenance of Roads and Bridges.


6 specifications

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