msd-proj-ak-12-00507 - specification for temporary repair

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MSD-PROJ-AK-12-00507 - Specification

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Landsmeer08.06.2020

Arie Nijs 05.03.2021 Marcha Jansen 05.03.2021

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Arie Nijs Marcha Jansen

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Table of Contents

1. Objective, target group and provision ..................................................................... 6

1.1 Objective ........................................................................................................................... 6

1.2 Definitions and Abbreviations ............................................................................................ 7

1.3 References ........................................................................................................................ 8

2. Requirements for piping repair methods ................................................................ 9

2.1 General ............................................................................................................................. 9

2.1.1 Personnel qualifications ...................................................................................................................... 9

2.1.2 Documentation .................................................................................................................................. 10

2.1.3 Inspection .......................................................................................................................................... 10

2.2 Philosophy ...................................................................................................................... 10

2.3 Defect Assessment ......................................................................................................... 10

2.3.1 Corrosion Assessment ...................................................................................................................... 11

2.4 Operating Condition Assessment .................................................................................... 14

2.5 Repair Options ................................................................................................................ 14

2.6 Testing of Temporary Repairs. ........................................................................................ 14

3. Products for Weldless Couplings And Clamps .................................................... 15

3.1 General ........................................................................................................................... 15

3.2 Off-the-shelf Designs ....................................................................................................... 15

3.3 Engineered Designs ........................................................................................................ 16

3.4 Suppliers ......................................................................................................................... 16

4. Products for Composite Wrap Systems ................................................................ 17

4.1 General ........................................................................................................................... 17

4.2 Off-the shelf systems ....................................................................................................... 18

4.3 Engineered Composite systems ...................................................................................... 18

4.4 Application to External Corrosion .................................................................................... 19

4.5 Application to Internal Corrosion ...................................................................................... 19

5. Acceptance Criteria for Damage to Flanges ......................................................... 20

5.1 Repair Methods for Flanges ............................................................................................ 20

5.2 RTJ - Flanges .................................................................................................................. 20

5.2.1 Acceptable damage/repairs to RTJ flanges ...................................................................................... 20

5.3 Raised Face Flanges ...................................................................................................... 23

5.3.1 Acceptable damage/repairs to RF flanges ........................................................................................ 23

5.4 Machining ........................................................................................................................ 24

5.5 Epoxy type flange repair .................................................................................................. 26

5.5.1 Requirements for application ............................................................................................................ 26

5.5.2 Raised Face Flanges ........................................................................................................................ 27

5.5.3 Ring Type Joints ................................................................................................................................ 28




5.6 Repair methods for piping ............................................................................................... 28

5.6.1 General .............................................................................................................................................. 28

5.6.2 Clamps for temporary repair ............................................................................................................. 28

5.6.2.1 Standard Clamp and Coupling for temporary repair .................................................................... 28

5.6.2.1.1 Straub-Open-Flex 1L .................................................................................................................... 29

5.6.2.2 Special Clamp for temporary repair ............................................................................................. 30

5.6.3 Engineered Composite Repairs ........................................................................................................ 31

5.6.3.1 General ......................................................................................................................................... 31

5.6.3.2 Design requirements .................................................................................................................... 32

5.6.3.3 Applicability of repair system ........................................................................................................ 32

5.6.3.4 Internal Corrosion ......................................................................................................................... 32

5.6.3.5 External Corrosion ....................................................................................................................... 33

5.6.3.6 Documentation ............................................................................................................................. 33

5.6.3.7 Deviations ..................................................................................................................................... 33

5.6.3.8 Inspection ..................................................................................................................................... 34

5.6.3.9 Training and qualification ............................................................................................................. 34

5.6.3.10 Curing of composite repairs ......................................................................................................... 34

5.6.4 Tape activated with water for temporary repair ................................................................................. 35

6. Accepted cold installation methods ...................................................................... 36

6.1 General instructions ........................................................................................................ 36

6.2 Selection of cold installation methods .............................................................................. 36

6.3 Materials ......................................................................................................................... 37

6.4 Manufacturers machines and rotating tools ..................................................................... 37

6.5 Qualification of methods .................................................................................................. 37

6.6 Qualification of personnel ................................................................................................ 37

6.7 Documentation ................................................................................................................ 37

6.8 Use of installation flanges in HC systems ........................................................................ 38

6.9 Requirements for mechanical couplings .......................................................................... 38

6.10 Metal to metal press fitted components ........................................................................... 38

6.10.1 Quickflange ....................................................................................................................................... 38

6.10.1.1 Seal .............................................................................................................................................. 39

6.10.1.2 Materials ....................................................................................................................................... 39

6.10.1.3 Special installation considerations ............................................................................................... 39

6.10.1.4 Training ........................................................................................................................................ 39

6.10.1.5 Qualified range for All systems .................................................................................................... 40

6.10.2 Lokring, LTCS-A333 and SS40 ......................................................................................................... 40

6.10.2.1 Description ................................................................................................................................... 40

6.10.2.2 Sealing ......................................................................................................................................... 41


6.10.2.4 Materials ....................................................................................................................................... 41

6.10.2.5 Training ........................................................................................................................................ 41

6.11 Special couplings ............................................................................................................ 42

6.11.1 Morgrip .............................................................................................................................................. 42




6.11.1.1 Description ................................................................................................................................... 42

6.11.1.2 Sealing ......................................................................................................................................... 43


6.11.1.4 Materials ....................................................................................................................................... 44

6.11.1.5 Training ........................................................................................................................................ 44

6.11.1.6 Qualified range ............................................................................................................................. 44

7. Appendices .............................................................................................................. 45

7.1 Appendix A: Design Data Sheet for an Engineered Repair (Ref basis ISO/TS 24817) .... 45

7.2 Appendix B: Suggested Technical Solutions ................................................................... 48

Table of Tables and Figures

Table 1 - Approved Products ........................................................................................................................... 16

Table 2 - Approved Products ........................................................................................................................... 19

Table 3 - Guideline for use of water-activated tape ......................................................................................... 35

Table 4 - Repair Classes ................................................................................................................................. 48

Table 5 - Technical solutions for piping repair and cold installation methods ................................................. 51

Figure 1 - Galvanic Table ................................................................................................................................ 13

Figure 2 - API BX ring Gasket when energised ............................................................................................... 20

Figure 3 - Type 'R' Gasket when energised .................................................................................................... 21

Figure 4 - Location of typical RTJ ring (type R) sealing surface...................................................................... 21

Figure 5 - Acceptable damage to RTJ flanges ................................................................................................ 21

Figure 6 - Damage to ring sealing surface ...................................................................................................... 22

Figure 7 - Damage to ring sealing surface ...................................................................................................... 22

Figure 8 - Damage on sealing surface ............................................................................................................ 23

Figure 9 - Inside edge damage ........................................................................................................................ 23

Figure 10 - Class 150# and 300# .................................................................................................................... 24

Figure 11 - Class 600# and higher (used on some older installations) ........................................................... 24

Figure 12 - Dimensioning of Ring-Joint Facing (all pressure rating classes) .................................................. 25

Figure 13 - Definition E modified and tf modified ............................................................................................. 25

Figure 14 - Straub-Open-Flex 1L type clamp .................................................................................................. 29

Figure 15 - Quickflange system ....................................................................................................................... 39

Figure 16 - Lokring system .............................................................................................................................. 40

Figure 17 - Example of Lokring component..................................................................................................... 40

Figure 18 - Morgrip System ............................................................................................................................. 42

Figure 19 - Morgrip Flange System ................................................................................................................. 43

Figure 20 - Morgrip Sealing System ................................................................................................................ 43




1. OBJECTIVE, TARGET GROUP AND PROVISION

1.1 Objective

The objective of this document is to outline the basic requirements for repair methods and cold installation

methods. The requirements in this document shall form the basis for repairs and cold installation methods

for plants in operation. This document is intended to provide guidelines for evaluation and assessment of

temporary repairs to pipework on the Neptune Netherlands platforms.

For the organisational aspects, refer to the document "raising a Temporary repaired TR Work Order

(doc ref 1319827).

When the need to apply a repair to a piping system arises, a rapid response is normally required. It is

normally preferred to perform repairs without "hot work", and there are a variety of weld less products to

enable this. This document appraises the products and places limitations on their use for hydrocarbon and

utility services. It is also intended that these guidelines will provide information on the application of such

repairs in order to control and prevent inappropriate application and serve as an aide and be used in

conjunction with the temporary repair procedure.

In the context of this work, a repair is taken to mean an existing pipe with a leak or identified defect which

is modified in-situ or a section replaced so that the system is fit for continued operation.

Repair methods described in this document is recommended for repair of the unacceptable damage to

flanges, pipes and fittings. The purpose of the repairs is to keep the system running until a replacement

can be made or as a permanent repair. This document is developed to achieve a uniform practice for the

repair of piping systems in operation. This document describes when and how to use patches, clamps, or

wrapping with composite materials, as a temporary or permanent repair method for piping systems, so

that normal operations can be maintained without unnecessary replacement. Choice of repair- and cold

installation method shall be based on a documented technical / economic evaluation.

There are five types of repair:

Replace like for like

Temporary repair, time limited solution

Permanent repair, not like for like but without time limit

Temporary repair requiring engineering approval, time limited solution

Permanent repair requiring engineering approval, not like for like but without time limit.

The cold installation methods described in this document are selected components that are found

qualified and acceptable for use on our platforms.




1.2 Definitions and Abbreviations

ESV Emergency Shutdown Valve

FKM Elastomer (Viton)

GRP Glass-Reinforced Plastic

HNBR Elastomer

IACS International Association of Classification Societies Ltd

NBR Elastomer (Nitrile)

NDT Non Destructive Testing

PCC Post Construction Code

PM Preventive Maintenance

PSV Pressure Safety Valve

PWHT Post Weld Heat Treatment

RF Raised Face

RTJ Ring Type Joint

SAP Systems, Applications, and Products in Data Processing

SCC Stress Corrosion Cracking

SJA Safe job analysis

TA Technical Assessment

WPQ Welding Procedure Qualification

WPQR Welding Procedure Qualification Record

WPS Welding Procedure Specification

can Statement with option for Vendor to implement.

competent person A person with predefined training and certificate

Criticality Verbal form used in to describe the evaluation of HSE / regularity consequences

due to a possible leakage

may Verbal form used to indicate a course of action permissible within the limits of this

specification

non critical

systems

Product or product code where all the following apply: The fluid handled is non-

flammable, nontoxic, and not damaging to human tissues.

Permanent repair Repair where improvement is considered sufficient to restore the integrity of the

pipe for remaining lifetime.

Pipe class design

pressure

The pressure at the system temperature according to piping class sheet

Plant(s) Verbal form used to define validity area of this document. Plant(s) includes topside

offshore installations and above ground on onshore plants / installations.

shall Verbal form used to indicate requirements strictly to be followed in order to

conform to the standard and from which no deviation is permitted, unless

accepted by all involved parties




should Verbal form used to indicate that among several possibilities one is recommended

as particularly suitable, without mentioning or excluding others, or that a certain

course of action is preferred but not necessarily required

System design

pressure

The maximum design pressure for a specific line given on the P&ID and line list or

PSV set pressure in ESV segment

temporary repair Repair where replacement or new repair is planned later and normally at the next

planned shutdown.

1.3 References

API 570 In-service Inspection, Repair and Alteration of Piping Systems

API 2201 Safe Hot Tapping Practices in the Petroleum & Petrochemical

Industries

ASME B16.5 Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24

Metric/Inch Standard

ASME B16.9 Butt Weld shapes

ASME B31.3 Process Piping

ASME PCC-2 Repair of Pressure Equipment and Piping

ISO/TS 24817 Composite repairs for pipework -- Qualification and design,

installation, testing and inspection

ISO 6162-1 Hydraulic fluid power -- Flange connections with split or one-piece

flange clamps and metric or inch screws -- Part 1: Flange connectors,

ports and mounting surfaces for use at pressures of 3,5 MPa (35 bar)

to 35 MPa (350 bar), DN 13 to DN 127

ISO 6162-2 Hydraulic fluid power -- Flange connections with split or one-piece

flange clamps and metric or inch screws -- Part 2: Flange connectors,

ports and mounting surfaces for use at a pressure of 42 MPa (420

bar), DN 13 to DN 76

General Specification 525

(MSD-PROJ-AK-12-000525)

Specification for Painting and Coating

General Specification 503

(MSD-PROJ-AK-12-000503)

Specification for Pipe Fittings and Valves




2. REQUIREMENTS FOR PIPING REPAIR METHODS

2.1 General

During inspections and execution of maintenance for plant in operation it is occasionally found damage

has occurred to pipe, flanges, valves or other equipment that requires some form of repairs. Acceptance

criteria's and repair methods are described in this paragraph. Choice of repair method, Evaluation of repair

method should be based on the following criteria:

Safety and risk consideration

Time until the next scheduled shutdown

System criticality, pressure-class/operational pressure and temperature

Extent of damage and the possibility for further development of damage (media and corrosion)

External or internal damage

The need for inspection

Complexity of repair

Accessibility for inspection

Geometric design, static and dynamic load of the component or system

Repair time and the consequences of shut down

Expected remaining lifetime

2.1.1 Personnel qualifications

Machining:

Machining shall only be performed by a qualified operator with knowledge / experience in the use of

necessary tools.

Application of composite materials (repair composites. GRP lamination, etc.):

Personnel that shall apply the coating shall have the necessary product knowledge and practical exercises

conducted under the supervision of the supplier or paint contractor. The operator shall have knowledge of

the required purity / roughness on the steel surface, the curing time / mix of product, application

techniques, safety, etc.

For composite repairs for pipe work the requirements in ISO/TS 24817 (Petroleum, petrochemical and

natural gas industries -- Composite repairs for pipework -- Qualification and design, installation, testing

and inspection) for "Installer qualifications" shall be fulfilled. On request written documentation /

certification for personnel qualifications shall be provided.

Use of compression type and clamp type fittings

Only personnel trained in the application of these systems shall be allowed to install them.




2.1.2 Documentation

A temporary repair that requires follow up or may have consequences for possible future repair shall be

documented within company guidelines, refer to "raising a Temporary repaired TR Work Order (doc ref

1319827).

2.1.3 Inspection

Repair of damages on piping systems should be categorised as a temporary or permanent repair (see

definitions) prior to performing the repair. Based on damage, damage mechanism and consequence of a

leakage a temporary repair shall be evaluated for the need for future inspections to ensure that the applied

materials / coating remains intact, thus preventing a further development of the damage.

2.2 Philosophy

For Piping Systems, the repair philosophy in descending order of preference shall be:

Replace like for like

Temporary repair, time limited solution

Temporary repair requiring engineering approval, time limited solution

Permanent repair requiring engineering approval, not like for like but without time limit.

Temporary repairs shall be shall time limited to the next scheduled maintenance stop of the system of

which the repair is a part with a maximum duration of 1 year. This time may only be deviated from after

approval by an authorised person.

2.3 Defect Assessment

The defect assessment shall be in line with 'Praktijkregels voor Drukapparatuur’:

3.1 Opstellen herbeoordelingsplan

3.2 Beschrijving en aanvaarding van inspectiemethoden en technieken.

3.3 Beoordeling van lnspectie en onderzoeksresultaten

4.1 Fitness for service

5.2 Stappenplan voor reparatie en niet ingrijpende wijzigingen

Consideration shall be given to:

Has the piping been replaced or repaired before?

Has the piping failed in the same manner as before?

Do redundant connections need to be replaced?

Is there an advantage in reducing the line size if practical?

Is the condition of tie-in flange faces acceptable?

Have operating conditions changed over the life of the problem area?

Has material selection been a factor?




2.3.1 Corrosion Assessment

To properly understand corrosion mechanisms a general description of the major corrosion mechanisms

is given in this paragraph.

The internal or external defects encountered are likely to be attributed to:

Uniform corrosion, general or localised attack.

Crevice Corrosion

Galvanic activity

Pitting

Erosion corrosion

Stress corrosion

Fatigue

In general, the following conditions increase the chance and severity of corrosion:

High temperature

High chloride concentrations (i.e. at lot of salt)

High CO2 concentrations

The presence of water

The presence of oxygen

Carbon Steel

In most cases corrosion of carbon steel is general corrosion, i.e. wall thickness, will reduce over a large area

at a uniform rate. If specific process conditions are right (or wrong) localised corrosion can happen such as

Top of Line corrosion, due to CO2 and condensing water. Carbon steel can also corrode locally due to a

corrosive liquid dripping on to steel. Also, external corrosion, due to damage of the coating, is generally

localised.

Carbon steel / CRA connections

The combination of carbon steel and CRA (Corrosion Resistant Alloy 316, duplex etc.) can also lead to

corrosion, specifically galvanic corrosion when the materials used are electrically connected and there is

an electrolyte (water) present. The CS acts as an Anode and the CRA is the Cathode. The CS will go into

solution (i.e. dissolve, disappear) while the CRA remains unaffected. The smaller the anode the faster it

goes into solution. If the anode is very large compared to the cathode, the rate of corrosion is slow.

Therefore, a 316L ½" plug in a carbon steel piping system will not cause a lot of corrosion, but a CS plug in

a duplex system will have a high corrosion rate.

The solution is to choose materials that are closer to each other on the galvanic chart or isolate the

materials from each other.




Galvanic Corrosion

Alloys are listed in the order of the potential they exhibit in flowing sea water. Certain alloys indicated by

the symbol (symbol) in low velocity or poorly aerated water, and at shielded areas, may become active and

exhibit a potential near -0,5 volts.




Figure 1 - Galvanic Table




CRA (Corrosion Resistant Alloys, 316L, duplex, etc.)

CRA's are corrosion resistant due to the passive layer that forms under the influence of oxygen during the

fabrication process. Damage to the passive layer will result in a galvanic cell much like galvanic corrosion

described above, only now within one material. The damaged area becomes the Anode, while the rest of

the pipe is the Cathode. Corrosion of CRA's is therefore localised corrosion manifesting itself as pits,

wormholes or cracks. These are difficult to detect and can propagate quite fast.

2.4 Operating Condition Assessment

A full assessment of the operating conditions to which the repair will be subjected shall be completed

including.

Fluid

Design pressure

Min/Max Operating Temperature

Location

Inspection Access

Hazardous Area

2.5 Repair Options

For repair options see Appendix B.

2.6 Testing of Temporary Repairs.

When a repair is necessary due to loss of wall thickness or a loss of containment (i.e. a hole) and the pipe is

repaired either for a defined period of time or as a permanent repair, the integrity of the repair shall be

proven. Testing shall be performed after completion of the repair and prior to bringing the line back into

service, compliance with En-13480 / Warenwet (0.9 x original test Pressure for 30 minutes duration).

Atmospheric open drain lines are the only exception and may be flushed or filled with water and leak tested

instead of doing a pressure test as described above.




3. PRODUCTS FOR WELDLESS COUPLINGS AND CLAMPS

3.1 General

There are numerous devices available that cover pipe clamps and pipe connectors. As their names imply,

the former usually clamp over the pipe while the latter replaces pipe connections, such as flanges, by being

designed to accept the bare ends of pipe.

Any repair performed using these devices shall be designated as either temporary or permanent as well as

"off-the-shelf' or "Engineered".

With either type (clamp or connector) the performance requires attention to the preparation of the pipe

surface receiving the clamp or the connector. As with over-wrap systems all loose paint and corrosion

deposits shall be removed, and the corrosion effects will be "stopped".

Leakage prevention is usually achieved through the use of elastomeric seals or linings (metal to metal)

incorporated in the devices casing, being forced against the pipe wall.

If used as a repair device on gas conveying lines they shall be classified as temporary, unless the clamp has

been engineered specifically for that situation.

Where used on any other service, "off-the-shelf' designs will only be applied following discussions with the

manufacturer on the suitability of the sealing material for the liquid being handled and on the pressure

rating of the clamp or connector body. Any device must be considered before application for its suitability

to the system design pressure (MAWP) and temperature range.

These devices may counter the effects of internal or external corrosion, but where there is a need for the

repair to contribute to the structural strength of the corroded pipe then only engineered designs shall be

considered as suitable.

A clamp is unlikely to be able to impart sufficient grip to resist axial movement. Depending on the

connector selected some do have a mechanical arrangement that can impart and resist axial movement.

3.2 Off-the-shelf Designs

The most common type of clamp in this design is the elastomer lined clamp, which is deployed by placing

it over the defective area and then tensioning it up circumferentially hence compressing the lining to make

a leak proof connection. A similar application description applies to those clamps using local split

circumferential seals instead of a lining; pressure energised seals are preferred.

These standard clamps are only considered suitable for straight pipes, where they are not required to

impart or resist a mechanical force in an axial direction. In addition, this style of clamp is restricted to class

150# rated piping systems. For class 300# and above, the more robust types of clamp with rigid body are

required.

For bends and where axial restraint is required, only engineered clamps should be utilised or standard off

the shelf clamps can be considered when additional support is added, the repair must engineered for the

application.




3.3 Engineered Designs

These may be considered for application in any medium as a permanent fix. By implication, these are

clamps have been specifically selected, designed and manufactured for a specific application and specific

service conditions.

Engineered clamps can be applied to hydrocarbon liquid and non-hydrocarbon liquid conveying piping as

either temporary or permanent repairs provided the supporting mitigation is prepared and deemed

acceptable.

Engineered clamps are usually a two-piece construction with the mechanical joint in one plane and

injection energised seals along the joint line and around the penetrations. With respect to the casing

pressure retention ability they are likely to be designed to a pressure vessel standard; usually either ASME

VIII or PD5500.

To improve rigidity of the clamp the internal void spaces between the pressure retaining casing and the

enclosed pipe is filled with a solidifying resin; that resin should not be relied on to act as an additional seal.

Due to a possible increase in weight/load using this type of clamp, a support review shall be performed. As

a result, additional support(s) may be required to mitigate undue pipe stress.

It is necessary to ensure that such clamps have incorporated in their design a provision for restraining any

axial movement that may arise due to the application.

Clamps with energised seals will require periodic inspection to ensure the seals remain energised.

Some Manufactures limit the number of times a clamp seal can be re-energised.

TYPE OF PRODUCT VENDOR PRODUCT

Clamp Furmanite Box clamp

Coupling Technom tools Lokring

Hydratight Morgrip

Verwater Quick Flange

Straub METAL-GRIP

Table 1 - Approved Products

3.4 Suppliers

For list of suggested technical solutions specific limitations, see “Appendix B: Suggested Technical

Solutions” to this document. This appendix is for internal use only. Other solutions may be accepted by

Company based on a technology assessment.




4. PRODUCTS FOR COMPOSITE WRAP SYSTEMS

4.1 General

Composite over-wraps are repair systems that encase the pipe in the vicinity of the defect by wrapping

around it several layers of an epoxy impregnated tape (wraps).

Depending on the pressure rating it is an alternative to weld repairs, fitting of metal sleeves or other

mechanical type repairs.

Over-wraps can be used to repair pin holes and compensate for lost wall thickness.

The flexibility of over-wrap materials and the application options are a key advantage with this type of

repair. It is possible to use over-wraps on steel piping Class 150# and 300#. Engineered over-wraps are

available for pressures above Class 300# but need rigorous testing and engineering qualification prior to

installation. All repairs using composite wrap shall comply with the requirements of ISO/TS 24817

(Petroleum, petrochemical and natural gas industries -- Composite repairs for pipework – Qualification

and design, installation, testing and inspection).

Over-wraps can be made compatible with most fluids conveyed on a production platform or gas

processing plant. However, these systems should not unless engineered specifically, be used on gas

systems where there will eventually be a through wall leak within the lifetime of the piping; the

permeability of the over-wrap generally makes it unsuitable for this application. In certain low-pressure

gas; systems there may be circumstances where there use may be technically justifiable considered

acceptable.

The application of over-wraps shall preferably be done with the system shutdown, but it only requires to

be drained where the repair is to a leak.

Over-wrap repair durability is only as good as the bond adhesion between the parent metal and the applied

over-wrap. Therefore, surface condition is the key to a successful repair. Surface abrasion by shot blasting

or other means, followed by chemical cleaning and finally a rinse with potable water is a satisfactory

approach. It is also preferable and good practice to ensure that the prepared surface is dry immediately

prior to applying the over-wrap.

Seawater shall not be used as a final rinse of any surface of the repair area; residual salt crystals can

adversely affect the bond. Once an over-wrap is applied it is necessary to leave it to harden (cure). Even

though it may be dry to the touch this does not indicate that it is fully cured or has reached its full strength.

Always follow the supplier's instructions on cure times and the environmental temperature associated

with these times is met. It may be necessary to build a habitat around the repair and employ warm air

blowers to achieve an adequate air temperature. Application temperatures usually have to be above 10ºC;

data accompanying the supplier's material should advise on this.




Where practicable the corrosion area or pitting should be arrested and filled with an "epoxy putty" prior to

applying an over-wrap; Over-wrap suppliers will advise on a suitable "putty" to use.

When applying an over-wrap, the suppliers' instructions on safety matters shall always be followed.

Rubber gloves, eye protection and long-sleeved coveralls shall be the least protective clothing worn by all,

including standby or inspection personnel involved in the repair. It is recommended that only technicians

trained in the application technique shall make these repairs.

4.2 Off-the shelf systems

These are composite over-wrap systems that can be purchased from a supplier as a "do-it-yourself” kit.

Only systems that come complete with "How-to-use", Safety instructions shall be purchased. As they have

not been "Engineered" for a specific repair the information on the number of layers to be supplied or the

extent of the overlap are unlikely to be included. For that reason, off-the-shelf systems shall only be used

on ANSI 150# piping, also, any repair shall be classified as temporary. Neither shall they be used in any

hydrocarbon liquid service where the repair is expected to contribute to the strength of the pipe or survive

a future leak.

As guidance on the number of layers and overlap to be applied, unless previous experience suggests

differently, the following rules of thumb shall be used.

(i) The minimum over-wrap built up thickness shall be greater than 5 mm or the thickness equivalent

to 5 layers of wrap, whichever gives the greater value.

(ii) The extent of the lay-up in way of the repair zone shall be the larger of 100 mm or (2 x sq root of

the (pipe o.d. (mm) x wall thickness (mm)) either side of the periphery of the area under repair.

Note: the 100 mm size will cover ASME Class 150# and 300# pipes up to 10" Nominal Diameter and wall

schedule 30 and 40. Above this range the extent of the lay-up shall be calculated.

4.3 Engineered Composite systems

These are composite over-wrap systems that shall be engineered, and purpose designed for each

application and pipe work configuration. They shall usually be applied either by specialist supplier or by

specially trained third party contractors under his supervision.

The design validation will be made by the specialist supplier or his appointed contractor and as a minimum

shall meet the requirements the AEA technology guidelines (March 2002). Published by H.S.E. (UK).

All designs shall be validated by qualification testing to demonstrate dependability and durability as well

as application technique and step plan. The latter two shall mirror the procedures that will be used for the

on-site repair, including surface preparation.

All designed over-wrap repairs shall be performed, as a matter of choice, by the supplier who has

engineered the repair and conducted the qualification tests. Similarly, the personnel involved in applying

the over-wrap shall also carry out the on-site repair.




4.4 Application to External Corrosion

For external corrosion, without perforation of the pipe wall, such a repair shall maintain the mechanical

properties of the pipe in the event of a complete perforation. The arrangement of such repairs shall permit

regular and meaningful inspection to be carried out. It shall also be a requisite that all surface pits etc. are

filled with epoxy putty prior to the application of the over-wrap.

For external corrosion, where there has been a perforation of the pipe wall, such a repair shall be classified

as temporary where the pipe is conveying hydrocarbon liquids. If the pipe were conveying non-

hydrocarbon liquids, then the repair can be permanent. The arrangement of such repairs shall permit

regular and meaningful inspection to be carried out.

4.5 Application to Internal Corrosion

It is likely that countering this form of corrosion can only be tackled by applying an Engineered Overlay to

the outside of the pipe. Therefore, applying the same approach as for external corrosion will be the only

course of action available. Should however suitable access be available then an internal repair may be

engineered. These latter repairs will also follow the terms noted for the external corrosion.

TYPE OF PRODUCT VENDOR PRODUCT

Composite Wrap

Synthoglass type SG

Table 2 - Approved Products




5. ACCEPTANCE CRITERIA FOR DAMAGE TO FLANGES

5.1 Repair Methods for Flanges

General requirements:

Before considering a repair with the use of repair compound (epoxy) or welding investigate

whether the damage can be repaired by machining.

Flanges must be checked with respect to critical dimensions and any measurements above

tolerance will be a deciding factor in whether welding is required or if machining is sufficient.

For welding repairs of gasket surface (ring grooves, flat face, raised face, etc.) machining tools

must always be used to prepare a new gasket surface. Other repaired areas can be smoothed by

grinding.

Repairs using epoxy shall only be performed to prevent further development of a damaged

component. This will have no compensatory effect to the strength of the component.

If the damage is greater than the acceptance criteria given, then one of the following actions must be

taken prior to operation:

Permanent repair: Damage removed by machining, welding or replacement.

Temporary repairs: Machining to a minimum thickness, the damage is not removed but reduced to

within the acceptance criteria and the damage is accepted for further operation.

Temporary repairs with compensating measures: Applicable when the damage is outside the

acceptance criteria. This option should only be used after a comprehensive risk assessment.

(Compensatory measures may be gas measurement on hydrocarbon lines and splash cover for

water injection etc.)

5.2 RTJ - Flanges

5.2.1 Acceptable damage/repairs to RTJ flanges

It is not acceptable to use epoxy for the repair of the ring sealing surface.

Damage that may cause the ring to be in contact with the bottom of the groove is not acceptable due to

possible metal to metal contact between the raised faces. There shall always be a gap between the RF of

the flanges; blade thickness gauge must be used to verify that there is sufficient gap, with the exception

of API flanges where the final gap is much smaller.

Figure 2 - API BX ring Gasket when energised




Figure 3 - Type 'R' Gasket when energised

A limited uniform circumferential mark from previous installed rings is acceptable if depth is less than

approximately 1 mm.

Figure 4 - Location of typical RTJ ring (type R) sealing surface

Damage outside the ring sealing surface:

Damage outside "ring sealing surface" can normally be

accepted. The ring sealing surface is normally visible when

opening flanges in operation. The ring sealing surface is

defined as the area between: maximum 15% of the groove

depth from top or bottom of ring groove, see Error!

Reference source not found..

Restricted damage outside the ring groove is acceptable

on the "raised portions.

Repair with epoxy can be performed for damage outside

the ring groove.




Figure 5 - Acceptable damage to RTJ flanges

Damage of the ring sealing surface

Damage is accepted if they do not cover more than

25% of the width of the ring sealing surface.

When there are multiple independent damages

across the ring sealing surface, the distance

between the damages shall be at least 4 times the

width of the damage.

Small patchy damage (pitting) may be acceptable

provided:

D ≤ 1mm

The distance between the pits: >2 x D

Damage area shall be less than 50% of the

ring sealing surface width.

D = diameter of each pit

Figure 6 - Damage to ring sealing surface

Figure 7 - Damage to ring sealing surface




5.3 Raised Face Flanges

5.3.1 Acceptable damage/repairs to RF flanges

Raised Face Flanges the damage can be repaired with epoxy as detailed below.

Where spiral wound gaskets are used, epoxy shall not be used on the active sealing surface.

Damage in the sealing surface

Localized damages as shown in the figure and

damages from the outside into the raised face

surface can normally be accepted.

When there are multiple pits within large parts of

the sealing surface, the clearance between the

individual pits shall be at least 4 times the extent

of each pit.

Damages in the seal faces, measured as a radial

projection, can be accepted if they do not cover

more than 30% of the width of the gasket surface.

Damages should not be deeper than 5mm, except

the edge damage as shown in Figure 8. A radial

projection is defined as the difference between an

inner and outer radius surrounding the damage

which is the radius from the centre line of the pipe.

Damages less than 0,5mm do not need to be

repaired.

Figure 8 - Damage on sealing surface

Damages of internal edge

Damages of internal edge around the bore, may be

acceptable if it does not cover more than 30% of

the width of the gasket surface:

BMax = 0.20 x A

A=OUTSIDE DIAMETER RAISED FACE-INSIDE DIAMETER PIPE

2

Figure 9 - Inside edge damage




5.4 Machining

Machining as a repair method for flanges (without welding) may be used provided that the thickness and

tolerances are according to ASME B16.5 and requirements given below.

A repair done by means of machining can result in that component thickness reaches its minimum value.

In such cases it is important to follow up with inspections to ensure that a further reduction of the material

thickness does not result in an unacceptable condition. For flanges that has been previously machined this

must be taken into consideration.

Prior to machining flange faces, the pipe flexibility shall be evaluated to ensure that the reduced length of

the flange not will impose additional stress to the piping system.

The pipe assembly after repair shall be according to C097-AKE-L-SP-0002 "Piping Fabrication,

Installation and Testing Specification" without springing or forcing pipe work to avoid undue stressing.

Raised face flanges

Machining of Raised Face flanges can be carried out according to the following guideline:

1) Machining of the flange raced face is acceptable if damage ≤ 1.2 mm for class 150# and 300#. If

the flanges touch the outer diameter this indicates too high bolt tensioning.

2) Machining of the flange raced face is acceptable if damage ≤ 6.2 mm for class 600#. If the flanges

have contact on the outer diameter this indicates too high bolt tensioning.

Figure 10 - Class 150# and 300# Figure 11 - Class 600# and higher (used

on some older installations)

3) Machining of the flange raced face with damage deeper than 1,2mm for class 150#, 300# and

600#.

a. Check the extent of damage (depth/height)

b. Height E shall be no less than 0,8 mm

c. Check the required machining of the flange ring (tf) to establish the re-establish the raised

face E of minimum 0,8 mm.

d. The flange thicknesses between all bolts holes shall be measured by callipers, minimum

measurements are noted.

e. Check that tf is thicker than minimum thickness according to ASME B16.5 after the

required machining

f. tf is thinner than minimum thickness according to ASME B16.5 flange calculation shall be

performed to verify the flange capacity.




g. Machining to be performed according to the geometry requirements of ASME B16.5.

RTJ flanges

Damaged RTJ flanges can machined according to the following guideline:

Figure 12 - Dimensioning of Ring-Joint Facing (all pressure rating classes)

a) Check the flange history to ensure that the flange is not previously machined

b) Check the extent of damage in the groove (depth/height)

c) Check the machining depth required to the flange face and groove to re-establish undamaged

groove dimensions

d) Based on c) establish the new E modified (height of raised face)

e) The flange thicknesses over all bolt holes tt are measured by calliper, minimum measurements are

noted.

f) tt modified in the groove is tt +E modified - E according to table 5 in ASME B16.5

g) Check that tt modified is thicker than minimum thickness according to ASME B16.5 (tt minimum)

after the required machining.

h) If tt modified is thinner than minimum thickness according to ASME B16.5 (tt minimum) flange

calculation shall be performed to verify the flange capacity. Calculation is not required if tt

minimum - tt modified according to table 2.2.

i) Machining to be performed according to the geometry requirements of ASME B16.5.

j) Check if piping system is flexible enough to compensate reduction of the length of the flange.

k) Check roughness of groove.

Figure 13 - Definition E modified and tf modified




5.5 Epoxy type flange repair

Epoxy type filler materials shall be applied according to the supplier's application procedure. The

Application Procedure shall be accepted by Company and be in accordance with the requirements of this

paragraph. Damages shall not exceed the acceptance criteria given above. in paragraphs 5.2.1 / 5.3.1

A Material Safety Data Sheet shall be available for all products.

The filler material datasheet shall state limitations to upper and lower temperature limits for dry

conditions and in contact with fluid. Materials in contact with the fluid shall be checked for chemical

resistance. The filler material limits shall be compatible with design criteria's for the piping system that it

shall be used on.

A repair with epoxy shall be categorised as a temporary or a permanent repair based on the criticality of

the system.

A temporary repair shall be subject to inspection to ensure that the applied coating remains intact, thus

preventing a further development of the damage.

5.5.1 Requirements for application

Preparation of damaged area:

For damages with deep pits, the transition between adjacent surfaces and damage surface need to be

ground to achieve a smooth transition with no sharp edges.

Epoxy must not be applied to "needle pitting" as these should always be opened up with grinding tools

before epoxy is applied.

Clean and dry surface:

If there is oil residue on the steel surfaces, for example in the pores, this must be removed before

application of epoxy. Salt residues must be removed and the cleanliness must be verified by using the

salinity tester. Dirt, grease, oil, etc. shall be removed with suitable detergent (Belzona NF, Chesterton 277

or equivalent). The environmental condition for applying the product shall be according to

recommendations from the manufacturer.

Blast Cleaning:

The surfaces shall be repaired must be blasted to SA 2.5 and a surface profile of min 75µm. Epoxy should

be applied immediately after blast cleaning to prevent the steel to oxidize.

If it is not possible to blast clean the surface should be sanded or scratched mechanically to achieve the

specified cleanliness and surface profile.




Application Technique:

Epoxy shall be applied according to recommendations from the manufacturer, using a stiff bristles brush

or plastic applicator. It is important to avoid air pockets between the applied mass and the surface.

Trapping of air must be avoided by wetting the surface profile with a stiff bristles brush and work the mass

into the surface profile to assure good adhesion to the surface. The coating is formed to the desired pattern

with a trowel/spatula.

Maximum thickness for application of epoxy is normally 6 mm, ref manufacturer's recommendation. If the

depth of the damage exceeds 6 mm additional layers is required to avoid air bubbles in the epoxy materials.

Due to amine diffusion on the surface during the first part of the curing process, additional layers must be

applied within 2 hours (at a temperature 20 - 25°C). If the time exceeds 2 hours the epoxy must be rubbed

or cold jet /dry ice blasting before the next layer is applied.

5.5.2 Raised Face Flanges

Minor damage:

By repairing minor damage to the gasket surface, where flange mould is not used, the epoxy is applied on

the flange surface as evenly as possible over the damaged area.

Apply epoxy according to the application technique described above.

Avoid filling the grooves with epoxy in the intact part of the gasket sealing surface.

After curing, the gasket surface shall be smoothed by machining or by using grinding paste, etc.

Larger damages repaired with flange mould:

Use of flange mould shall be according to recommendations from the manufacturer. Flange mould and

bolts shall be applied with minimum 2 layers with a suitable release agent.

Apply epoxy according to the application technique described above. By using the plastic applicator

additional material shall be applied as a V shaped to ensure that trapped air is squeezed out during

assembly of the mould.

The profile in the flange mould shall be wetted using stiff bristles brush and extra material shall be applied

so that the obstruction of air is avoided. The flange mould shall be pressed directly against the flange

surface and the bolts tightened using the cross tightening technique while the excess epoxy is removed.

The flange mould is fabricated with machined grooves (gramophone grooves) which creates a replica in

the epoxy flange facing.

The curing shall be according to the manufacturer's recommendation. After curing the bolts shall be

loosened and release the mould by using flange mould jack bolts. The form should not be hammered loose.




5.5.3 Ring Type Joints

Epoxy can be used to completely fill the ring groove and cover the complete face of the flange, effectively

changing the flange to a flat face. Only a flat face gasket can now be installed. This type of repair requires

TA approval. (HOLD)

5.6 Repair methods for piping

5.6.1 General

Below the following terminology are used:

Pipe class design pressure: The pressure at the system temperature according to piping class

sheet.

System design pressure: The maximum design pressure for a specific line given on the P&ID and

line list or PSV set pressure in ESV segment.

The repair of piping shall be performed to meet the pipe class design pressure and temperature.

When there are no other alternatives than repairing the line according to the system design pressure, the

repair shall be approved by the system technical responsible and discipline technical responsible.

The repair shall be documented in Maximo or other relevant systems.

Repair of a pipe according to operational pressure is not acceptable.

The below described methods shall not be used when cracks are present.

For list of qualified technical solutions specific limitations, see appendix to this document. The appendix is

for internal use only. Other solutions may be accepted by Company based on a technology assessment.

5.6.2 Clamps for temporary repair

Clamps may be used as a temporary repair to stop a leakage or to reinforce and secure the integrity when

the wall thickness is reduced.

5.6.2.1 Standard Clamp and Coupling for temporary repair

This section includes clamps and couplings that can be installed without cutting the pipe.

Clamp/coupling may be used as a temporary repair to stop a leakage or secure the integrity of the piping

system when the wall thickness is reduced.

Lifetime is limited to the first opportunity to perform a permanent repair. A permanent repair shall be

performed maximum 3 years after the temporary repair.

Standard clamp/coupling shall be used according the requirements herein and to manufacturer’s

installation procedure.




The clamp/coupling materials shall be selected and evaluated based on the pipe materials and location

due to exposure to saliferous atmosphere.

The soft sealing material shall be compatible with the medium and temperature.

Requirements for fire insulation shall be evaluated based on the system criticality and area fire

classification. If clamp/coupling with soft sealing material is used on firewater systems, the

clamp/coupling shall be fire insulated.

The damage shall be completely covered by the clamp/coupling and the pipe shall be free from damages

in the clamp/coupling seal area.

Establish work order for permanent repair when temporary clamp/coupling is used.

For fully rated piping (Typical: 20 barg / class 150#) shall the piping system be de-rated to maximum

system design pressure. The maximum system design pressure shall be below or equal to the

clamp/coupling maximum pressure as specified in the tables below.

5.6.2.1.1 Straub-Open-Flex 1L

Straub-Open-Flex 1L rubber seal clamp can be used as temporary repair method on systems with

maximum system design pressure 16 barg.

Description

Straub-Open-Flex 1L shall be installed without

cutting the pipe and is therefore suitable for

temporary repairs on pipes with typical minor

corrosion damages.

Figure 14 - Straub-Open-Flex 1L type clamp

Sealing materials

Soft sealing material shall be NBR.

Clamp Materials

The materials shall be SS316 (manufacturer's materials specification W5)




5.6.2.2 Special Clamp for temporary repair

Split sleeve repair special clamps may be used as a temporary bolted type repair method to stop leakages

or to secure the integrity when the wall thickness is reduced. These types of clamps are typically tailor-

made and may be used based on economical and safety evaluation compared with a system shutdown.

To ensure correct design of the clamp the following information shall be provided to the

manufacturer/supplier:

Pipe size and reference to actual piping class sheet and the exact measured diameter/ovality of

the pipe.

Available length and volume around the pipe and restrictions if any

Piping isometric (geometry)

Working condition (access, scaffolding requirements)

System design pressure and temperature range

Required lifetime the repair shall be designed for

Material handling equipment available and the need for lifting lugs

Bolt lubricant used on the plant

Environmental condition (saline atmosphere, water spray, mechanical ventilated area, etc).

Medium and chemical content (e.g. methanol, oil, hydrocarbon gas, etc.)

Supplier shall advise:

Required pipe surface finish where clamp shall be installed

Clamp weight and specific material handling requirements

Required assistance for installation of clamp

Supplier shall provide:

Special clamp with design documentation including calculations and drawings

Installation procedure including bolt torque required for bolted connections based on specified

lubricant

Installation if requested

Specific requirements:

The damage shall be completely covered by the clamp

The clamp should be accessible for visual inspection. (Need for inspection shall be evaluated based

on the media in the pipe).

Establish work order for permanent repair

The repair shall be documented in relevant systems.

Requirements for fire insulation shall be evaluated based on the system criticality and area fire

classification. If clamps with soft sealing material on firewater systems, the couplings shall be fire

insulated.

The use of clamp shall be in accordance with ASME PCC-2 "Mechanical Clamp Repair"

Clamp shall as a minimum be approved for system design pressure




Additional weight caused by the clamp shall be evaluated by a stress/pipe support engineer.

Evaluate if the clamp shall be able to take additional axial loads (structural clamp)

Ensure that the chemical resistance of gasket materials is compatible with the medium

Default clamp materials should be CS. However the clamp materials should be evaluated based on

pipe material, the corrosion effect of the medium and expected lifetime

5.6.3 Engineered Composite Repairs

5.6.3.1 General

The purpose of piping repair by Composite Repair is to reinforce the piping with unacceptable wall

thickness in order to re-establish the pipe's pressure capacity for systems 600# and above.

The quality of the composite repair system comprises, but is not limited to:

Initial pipe

Surface treatment of initial pipe

Composite Repair Systems including reinforcement (e.g. fiberglass) and resin (e.g. epoxy)

Qualification, design, installation, testing and inspection of Composite Repair shall be according to ISO/TS

24817 ("Petroleum, petrochemical and natural industries - Composite repairs for pipe work - Qualification

and design, installation, testing and inspection"), except as modified herein.

Other general requirements:

For enquiry to repair system Supplier, appendix A shall be filled in by Neptune and issued to

supplier (if applicable), to ensure relevant information is available to design the composite repair.

The personnel used to perform the composite repair shall meet the requirements in section 5.6.3.9

The qualified Suppliers and limitations to the products are listed in appendix B. The appendix is for

internal use only. Other Suppliers may be accepted by Company based on a technology

assessment/Qualification.

The repair shall be done according to Suppliers installation procedure.

Surface finish shall be minimum SA 2.5 in bonding area. (A coupon may be located above the thin

area or the hole in the pipe. The area under the coupon or a reduced surface finish locally on the

damaged area may be acceptable if there is a risk for further damage/leak. The area covered by

the coupon or the local damage area not blasted shall be taken as the actual defect.)

Post curing shall be specified by Supplier (if required).

Requirements for fire protection shall be evaluated

Fire protection shall be applied if required. Alternative methods of fire protection may be used

upon Company acceptance.

For pipes with both internal and external corrosion, the table for internal corrosion shall be used.




5.6.3.2 Design requirements

In addition to ISO/TS 24817, the following design requirements apply for the repair system:

The resin shall be self-extinguishing.

The pipe without laminate shall be able to sustain all loads except for the circumferential load from

internal pressure (hoop stress). Additional pipe supports may be added to fulfil this requirement.

5.6.3.3 Applicability of repair system

Composite Repair Systems shall not be used to repair:

Circumferential and longitudinal cracks

Damage surrounding the entire circumference of the pipe, unless detailed pipe stress calculations

can document that remaining piping has sufficient structural strength (without Composite Repair)

Repair lifetime

The required lifetime of the repair system shall be defined in the repair data sheet, Appendix A.

For the purpose of standardization the minimum lifetime of the repair shall be designed for 10 years unless

specified otherwise in the tables below.

Short lifetimes are intended to apply to those situations where the repair is required to sustain until the

next shutdown. It may be limited by the defect type and service conditions, e.g. internal corrosion.

Long lifetimes are intended to apply to those situations where the repair is required to re- instate the

substrate to its original design lifetime or to extend its design life for a specified period.

Once the lifetime of the repair has expired, the owner shall either remove or revalidate the repair system.

5.6.3.4 Internal Corrosion

General requirements for internal corrosion:

Prior to lamination, carry out corrosion mapping of the damaged area.

Establish corrosion rate based on historical data.

For substrates with active internal corrosion, the repair laminate shall be designed on the

assumption that a through-wall defect will occur if the remaining wall thickness at the end of

service life is expected to be less than 1 mm.

If it can be documented by NDT that there has been no further wall thinning then the repair lifetime

may be extended. Repeat inspection at determined intervals to evaluate development of damage.

Damages that are not covered by below acceptable limits shall be subject to local evaluation and

deviation request (See Appendix A).

Max extent of damage 25% of circumference.




5.6.3.5 External Corrosion

General requirements for external corrosion:

Prior to lamination carry out corrosion mapping of the damaged area.

Repair lifetime shall be defined and included in the design data sheet in appendix A and shall be

within the lifetime guaranteed by the composite suppliers.

Damages that are not covered by below acceptable limits shall be subject to local evaluation and

deviation request (See section 5.6.3.7)

Max extent of damage 25% of circumference

5.6.3.6 Documentation

In addition to documentation requirements detailed in ISO/TS 24817, the following additional

requirements apply:

The repair system supplier shall provide application procedure developed by the supplier and

accepted by the Company.

HSE datasheets for products used shall be according to "Technical environment for offshore

platforms and facilities".

Applicable isometric drawings shall be updated and inspection number shall be included on the

drawing.

The following As Built documentation shall be provided: Design report, material data, surface

treatment report, hardness/curing log of primer and laminate build up.

For documentation update requirements refer to EPN Management system

5.6.3.7 Deviations

Deviations should be avoided. However if a deviation is required the following information shall be

provided in the application through the MOC procedure

Design data sheet in Appendix A (including important information like expected future corrosion

rate for internal corrosion/erosion). One data sheet to be completed for each repair.

Pictures of piping to be repaired

Applicable isometric drawing(s) and P&ID(s)

The content in the dispensation application shall be based on local knowledge of the piping system, pipe

supporting and medium in the pipe and shall be technical recommended by the local piping responsible.

Dispensation shall contain documented information about corrosion rate, details of damage, area, layout

(geometry) etc. This information shall be added into the Data sheet in Appendix A.




5.6.3.8 Inspection

Laminate

The repair system supplier shall provide guidance on techniques and methods for inspecting the repair

system (ref. ISO/TS 24817). This guidance shall as a minimum include defect types and allowable limits for

the composite repair systems. These techniques shall be applied immediately after the repair system

application and during the lifetime of the repair system.

The lamented area shall be inspected according to extent of the damage and consequence of a leakage.

The maximum inspection interval shall be 4 years, in order to determine condition of the repaired system.

5.6.3.9 Training and qualification

This section outlines the minimum qualification of installer and supervisor on NEPTUNE ENERGY BV

installations or plants:

The basic skills/experience and training level of Installer and supervisor shall be according to the

requirements given in ISO/TS 24817.

The personnel that shall undertake repairs shall be approved to class 3 repairs and defect type B

qualification test (ref. ISO/TS 24817) and shall hold a certificate providing details of the repair

method qualified for. The certificate shall follow the holder and shall be documented when

requested. The validity of the certificate shall follow ISO/TS 24817.

The employer of the repair system installer shall keep a record of the completed training and a

logbook of all repair applications performed.

5.6.3.10 Curing of composite repairs

The time for full cure is dependent on the type of resin used in the repair and on the ambient conditions.

The repaired substrate may be returned to service only after full cure has been achieved.

Supplier shall describe required temperature and time for curing in their design report and calculations.




5.6.4 Tape activated with water for temporary repair

Defect type Maximum system design pressure (bar)

for 150# piping class

Maximum

temperature

(°C)

Service

conditions

Maximum

lifetime

(years)Surface

preparation

Sa2.5

Surface

preparation

ST3

Surface

preparation

ST2

Internal

corrosion

(wall loss

and/or

through

wall defect)

15 (1) 10 (1) 2.5 (1) 70 Non critical

systems.

Limited to

water

systems See

guideline in

Appendix C

1

Note 1: For large defects, i.e. greater than a diameter of 20 mm then this pressure limit should be

reduced by 50%.

Table 3 - Guideline for use of water-activated tape

Water-activated tape (water activated polyurethane) is a quick temporary repair method used to seal or

stop leaks by winding a glass fibre cloth with resin around the pipe.

Requirements:

Pipe dimensions 8" and smaller.

Use Supplier’s installation procedure




6. ACCEPTED COLD INSTALLATION METHODS

6.1 General instructions

The methods for cold installations described in this section can be used as permanent installations and will

as a basis not require special inspection and follow up.

Surface preparation and protective coating of cold installation methods shall be performed according to

General Spec 525 "Surface preparation and protective coating" (MSD-PROJ-AK-12-00525).

All couplings shall be used according to manufacturer's recommendation and procedures unless described

otherwise in this section.

All permanent couplings not included in piping class shall be registered as a special item. See paragraph

6.7. Installation shall be according to Manufacturer's instructions. Additional requirements are specified

where required for each coupling type.

6.2 Selection of cold installation methods

These cold installation methods shall only be used for tie-in’s, replacement of spools (repair works) and

modifications for plants in operation after evaluation of all other alternatives.

General evaluation:

Service

Pressure Class

Temperature

Area classification

Lifetime evaluation based on coupling materials and remaining plant lifetime

Tie-ins to existing systems:

Condition of existing piping systems (wall thickness, ovality and surface condition)

Evaluation of tie-in alternatives for live systems

Hot tapping with clamp on branch

Evaluation of tie-in alternatives for systems that are shut down

Mechanical couplings

Piping system installation methods:

Evaluate if spooling with cold installation methods is acceptable

Cost of alternative acceptable methods

The degree of prefabrication of shop made spools




6.3 Materials

All components shall have equivalent to or better corrosion resistance than the component they are

connected to, including low/high temperature compatibility. The possibility of galvanic corrosion should

be kept in mind when selecting the repair method.

All sealing material shall be suitable for the design pressure, temperature and the services specified. The

materials and gasket shall be compatible with the medium and temperature.

6.4 Manufacturers machines and rotating tools

Several of the products described in this document include use of rotating and other equipment that may

represent a risk for injury. Procedure for use of equipment shall be made available to personnel involved.

The rotating equipment shall be CE marked or have records of safe use.

6.5 Qualification of methods

The products specified in this document are those that so far have been through a technology assessment

or qualification. Other manufacturers may be accepted by Company based on a technology assessment /

qualification.

The technology assessment shall in general be based on test documentation from the manufacturer

including type approval documents and certificates.

6.6 Qualification of personnel

All products shall be installed by competent personnel. Special requirements for installation are

specified for each product.

6.7 Documentation

Piping components defined in the plant's piping classes 503 "Piping and Valve Specification" (MSD-PROJ-

AK-12-00525) shall be documented according to standard documentation requirements. For other

components Special Item numbers shall be used and marked up on the P&ID. If specific couplings are used

widely in a system, a general note can be added on the P&ID to document the use. Location of the special

item shall be marked on the Piping Isometric.

Temporary repair documentation shall be attached to the TMOC.




6.8 Use of installation flanges in HC systems

The flanges that are described in this section are flanges that are used as alternative to field welding and

normally not split during the facilities lifetime. The intention with this paragraph is to open up for use of

flanges in areas where not accepted in new plants / Greenfield projects.

To maintain the intention of the safety case, which require that the number of flange connections should

be kept to a minimum, the following principles will apply to plants in operation.

Welded connections are preferred, but where there is a major cost / time benefit, spooling with flanged

connections may be an alternative under the following conditions:

Use of metallic ring gasket or spiral wounded gasket

Maximizing the length of spools, i.e. the number of flange connections should be minimised.

Use of installation flanges is accepted unless the explosion risk is above acceptance criteria for the area.

When evaluating the use of installation flanges, the existing risk in the area must be taken into

consideration. For example if the explosion risk is already above the normal tolerance criteria,

care/measures should be taken not to increase the risk any further.

6.9 Requirements for mechanical couplings

General requirements:

The pipe surface area shall be prepared prior to installation of the coupling

For welded pipe the weld bead shall be ground flush with pipe wall

Visual inspection shall be performed after installation.

6.10 Metal to metal press fitted components

For general technical requirements see sections 6.1 - 6.9.

6.10.1 Quickflange

The Quickflange coupling consists of a modified ASME flange installed with a hydraulic tool. This flange is

machined in such a way that it can slide onto the pipe, and the hydraulic tool expands the pipe into grooves

machined inside the flange. The result is a metal- to -metal seal between the pipe and flange.

The crevice on the inner and outer bore of the flange is sealed with a sealing compound to prevent crevice-

corrosion.




Figure 15 - Quickflange system

6.10.1.1 Seal

The sealing system is a metal- to -metal seal between the pipe and flange. A sealing compound is used to

prevent crevice-corrosion.

6.10.1.2 Materials

The range of materials that can be used are:

Low strength carbon steel

Duplex

SS 316

Cunifer

6.10.1.3 Special installation considerations

The existing pipe where Quickflange is to be installed shall have acceptable wall thickness and shall be

within tolerances as regards ovality and damage. Visual inspection shall be performed after installation

and no cracking of base material is allowed. Pipe condition shall be checked for damages prior to

installation. Minor damages may be accepted based on acceptance from competent person / Contractor.

Sealing compound shall be used between pipe and flange to avoid corrosion. The sealing compound shall

be qualified for the service. Typical sealing compound is Belzona Type 1111. NBI Typical curing time before

testing is 4 hours.

6.10.1.4 Training

Quickflange shall be installed by competent person with "Quickflange certificate", according to

Quickflange's procedures.




6.10.1.5 Qualified range for All systems

Quickflange is approved to 20 bar (pipe class 150#).

Quickflange may be used as permanent coupling on fully rated 150# piping class.

6.10.2 Lokring, LTCS-A333 and SS40

6.10.2.1 Description

Lokring pipe coupling consists of three parts: fitting body and two driver rings.

The coupling is installed on the outer surface of the pipe and the rings are pressed into the fitting body

using a hydraulic tool.

Figure 16 - Lokring system

Lokring is delivered as a coupling for straight pipe and couplings including reducers, caps, elbows, tees,

flanges and adapters.

Figure 17 - Example of Lokring component




6.10.2.2 Sealing

Lokring sealing zone is defined as the area from pipe end and 1.5 x D inward.

The coupling has three metal-to-metal seals at each end. These seals are part of the coupling body and

pressed into the pipe wall when the driver ring is pressed over the fitting body. The seal are called Primary

Seal, Main Seal and the Outboard Seal as shown in the figure above.


Longitudinal scratches of any significance on the sealing area must not occur. Elevations such as

longitudinal welds, must be ground smooth with the pipe. Bumps or flat sections of the pipe must not

occur. Dimension Tolerance and ovality is controlled by an interpreter that comes with installation tool.

After installation of a lokring coupling care should be taken to restore the paint system on the pipe and

coupling as soon as possible to avoid crevice corrosion.

6.10.2.4 Materials

The coupling is delivered in material qualities CS-MAS with max corr. Allowance 1.5 mm, LTCS-A333 with

max corr. allowance 3.2 mm and 316 SS.

The coupling in carbon steel supplied in quality ASTM A675 or A513 can be used to pipe in quality ASTM

A106, A333, A53, A53E, A53S and A587.

The coupling in stainless steel is supplied in quality ASTM A276 gr. 316L SS and ASTM A479 gr. 316L SS

and can be used on pipes in quality ASTM A312 gr. 316 or 316L. The coupling of stainless steel can also be

used on pipes in the above-mentioned carbon steel grades.

6.10.2.5 Training

Lokring shall be installed by qualified personnel with "Lokring certificate", according to Lokring's

procedures.

Training required for installation is 4-hour courses qualifying for operator's certificate.




6.11 Special couplings

For general technical requirements see sections 6.1 - 6.9.

6.11.1 Morgrip

6.11.1.1 Description

Morgrip product's may be used for critical system and high pressure repair and is available in sizes ½" - 24".

The MORGRIP design comprises of 2 key elements:

The mechanical gripping system, which comprises of balls rolling on tapers and swaging into the

outer surface of the pipe to produce the required mechanical grip

The sealing system which consists of metal-graphite-metal composite seals compressed radially

onto the pipe outer surface

Number of gripping segments varies depending on the material, wall thickness and pressure.

External test ports are normally a part of the coupling. The test port may be used to verify the sealing

system prior to applying pressure in the pipe or to verify no leakage through the first sealing barrier after

pressurizing the pipe. The test port will normally not be under pressure.

Morgrip connectors may be supplied as a pipe connector, flange couplings and end cap.

Figure 18 - Morgrip System




Figure 19 - Morgrip Flange System

6.11.1.2 Sealing

The Morgrip sealing system consists of graphite seal combined with anti-extrusion rings on both sides of

the graphite ring.

Seals are energised by connector bolting (Tensioning or Torqueing):

Twin seals with external test facility as standard

Tolerant of surface imperfections, pipeline diameter tolerances and high/low temperature

Figure 20 - Morgrip Sealing System





Due to normally high weight of the coupling additional supporting need to be evaluated.

Installation of Morgrip does not require special tools other than cutting equipment and bolt tightening

equipment.

6.11.1.4 Materials

Coupling and anti-extrusion rings may be delivered in Carbon Steel, 316 Stainless Steel and Duplex

Stainless Steel.

6.11.1.5 Training

MORGRIP connectors shall be installed only by qualified Hydratight personnel with documented

qualification. Product specialists and installation technicians can be supplied direct from Hydratight on a

case-by-case basis.

If a significant order of topside connectors is required for a single installation, then Hydratight can offer

training packages for NEPTUNE ENERGY BV technicians to enable fast turnaround during shut down

periods.

6.11.1.6 Qualified range

Morgrip connectors may be used as permanent coupling.

Taylor-made Morgrip connectors may be supplied for sizes 1" to 42" and for pressure class up to and

including 2500#.




7. APPENDICES

7.1 Appendix A: Design Data Sheet for an Engineered Repair (Ref basis ISO/TS 24817)

This data sheet shall form the basis of the record of the repair and scope of work provided by the owner to

the repair system supplier, and shall be used in the preparation of the design of the repair if applicable.

One data sheet shall be completed for each repair required. This shall form part of the documentation to

support Company's permanent record. (Maximo, Synergy or TMOC)

Customer Details

Contact person

Company and Plant

Address

Telephone

e-mail

Pipe Details

Location (module and if

the area is classified)

Pipe identification / line

number(s)

Pipe item reference

(typical: pipe / elbow /

tee)

Pipe specification

Material

Pipe diameter

Wall thickness acc. to

pipe spec. (mm)

Medium

Design Temperature Minimum Maximum

Pipe coating

Insulation

Is there existing repair

on pipe for leak seal

Risk Assessment

Criticality

(critical / non-critical)

Repair lifetime

Other data

Loading

(See Note 1 and 2)

System Design

(temporary repair)

Pipe Class Pressure

(Permanent repair)

Comments

Pressure rating (bar)




Axial load (kN)

Bending moment (Nm)

Shear load (kN)

Torsion (Nm)

Other loads (N)

Note 1 Any original design calculations / stress isometrics and piping isometrics should be appended to this data

sheet.

Note 2 Loads should be defined as either sustained or occasional in the comments column.

Details of Defect Area

Attach drawings of pipe system, inspection reports, digital photographs, etc. where available.

Indicate any access restrictions and proximity to other equipment.

Type of defect

(corrosion, pinhole,

crack.)

Location of defect on

elbow (see fig. x below)

Intrados Extrados

Location of defect. (12

on top of pipe and 6

bottom of pipe)

Is the defect circular

around the pipe

Defect location External (x) Internal (x)

Current wall thk (see fig.

y below)

Tmin 5 (mm) Tmin 6 (mm)

Current Area of defect

(see fig. y below)

ØD1 (mm) ØD2 (mm)

Expected wall thk (see

fig. y below)

Tmin 5 (mm) Tmin 6 (mm)

Expected Area of defect

(see Figures below)

ØD1 (mm) ØD2 (mm)

Cause Corrosion Erosion

Expected corrosion rate

(mm/year)

Fig. x: Definitions for elbow Fig. y: Definition of pipe wall thickness and areas

Anticipated Conditions during Implementation of Repair

Pipe temperature (°C)

Ambient temperature

(°C)




Pipe pressure (MPa)

Pipe contents

Humidity (%)

External environment

Constraints

Facilities to be Provided by Client / Installation (surface prep., etc.)

Other Information

Notes: This section should include any remarks on previous repairs, fire protection requirements, etc

Prepared By: Date:




7.2 Appendix B: Suggested Technical Solutions

The table below provides a list of process fluids and the allowable repair class for each.

Other solutions may be accepted by Company based on a technical assessment.

The responsible persons for the technical assessment shall be the Piping or Mechanical TA.

Allowable Repair Class

Produced Fluids Class A – Safety (or Environmental) Critical

Engineered Repair OnlyProduced Oil

Produced Gas

Fuel Gas

LP& HP Vent

Chemical Injection (High Pressure)

Water Injection (High Pressure)

Produced Water Class B – Safety (or Environmental) Critical

Engineered Repair Preferred. Non-Engineered

Repair may be suitable in some circumstances but

only when supported by appropriate assessment.

Closed Drains / Glycol Systems

Chemical Injection

Fire Water / AFFF

Open Drains (Hazardous)

Diesel

Domestic Services

Heating / Cooling Medium (Water Based)

Seawater Class C - Non-Safety Critical Non-Engineered

Repair Allowable Water Injection (Low Pressure)

Air Systems

Open Drains (Non-Hazardous)

Table 4 - Repair Classes




The technical solutions for piping repair and cold installation methods outlined in Table 5 below.

Restrictions and conditions for use are stated for each repair and cold installation methods. An approved

dispensation is required for solutions not listed in table below. Additional qualified piping repair and cold

installation methods to the products listed below described herein.

Fluids Repair Rating

(Press. / Temp)

Pipe

Material

Typical Products NOTES

See Table 4 for

Class B & C Fluids

150#

All

Straub

Axial grip type coupling to

be used.

Size range 1” to 8” NB.

Larger sizes only on

approval by Tech Auth.

Use NBR seal

METAL-GRIP coupling

(20Bar g)

-20 to 80°C

Class A, B & C To 300 Bar gAll except

GRE

Pressure Containment

Clamp

Furmanite Ltd

Engineering specification

required for procurement.

Size range 4” to 24” NB

Specialist vendor

installation. Nitrile Seals

Optional grout sealant.

Class A, B & CTo 2500#

-40 to 120°C

All except

GRE

Morgrip

Hydratight LtdEngineering specification


Size range 1” to 24” NB

Specialist vendor

installation.

Class A, B & C All ratings AllBox clamp

Furmanite Ltd

Engineering specification


Specialist vendor

installation.

Fire protection

requirements to be

considered.

Not acceptable to over

wrap with composite repair

system as long term.

Cannot take axial loads





(Press. / Temp)

Pipe

Material


Class B & C

150# (20Bar g)

-10C° to 60°C

All materials Syntho-glass

For leaking pipes Uni-wrap

must also be applied.

Recommended as a

temporary DLR only.

Class A, B & C

<50 Bar g

<90 °C

All except

GRE

Belzona 1111 (Super

Metal)

Belzona International

Ltd

A two-component repair

and rebuilding material

based on ceramic steel

reinforced polymer system,

for flange facing only.

Class A, B & C

<50 Bar g

>90, <120 °C

All except

GRE

Belzona 1511 (Super HT-

Metal)

Belzona International Ltd

A two-component paste

grade system based on a

silicon steel alloy blended

with high molecular weight

reactive polymers &

oligomers. When cured,

the material id durable yet

fully machinable, for flange

facing only.

Class A, B & C

<50 Bar g

-50 to 180 °C

All except

GRE

Belzona 4301 (Magma

CR1 Hi-Build)

Belzona International Ltd

A high-performance two-

part paste that protects

against chemical attack,

for flange facing only.

See Table 4

For fluid Class

A, B & C

150#

300#

600#

900#

All except

GRE

Lokring Lokring

Technology LLC

½” up to and included 4”





(Press. / Temp)

Pipe

Material


Class B & C Fluids

150# (20Bar g)

-20C° to 80°C

All except

GRE

Quickflange

Quickflange AS Engineering specification


Size range 1” to 12” NB.

Specialist vendor

installation. Metal to metal

& grout seals ASME B31.3

Table 5 - Technical solutions for piping repair and cold installation methods

msd-proj-ak-12-00507 - specification for temporary repair

Documents