Design, Manufacturing, Supply, Erection & Commissioning of Heat

Treatment Furnace with inert atmosphere

1. Scope:

The scope of supply and services include design, manufacturing, inspection, testing at

supplier's works, packing, safe delivery to purchaser's site, erection and commissioning,

performance trial and guarantee / warranty of continuous heat treatment furnace and its

accessories as per details given below.

2. Purpose:

Continuous heat treatment of various grades of stainless steel / Inconel tubes with argon

quenching for obtaining required mechanical & metallurgical properties without coloration

on tube surface (Tube inside & outside).

3. Furnace design Parameters:-

a) Material to be heat treated : Stainless steel/ Inconel tubes

b) Approx density of tube : 8g/cm3.

c) Tube OD to be heat treated : 4mm to 25mm

d) Tube thickness to be heat treated : 0.25mm to 3mm

e) Tube length to be heat treated : 1.5m to 7m

f) Production rate : 90 kg/hour

g) Quenching rate : 1200°C to 400°C in 90-120 seconds

h) Maximum furnace operating temperature : 1200°C

i) Soaking time :60 - 600 seconds at set temperature

j) Job temperature uniformity: ± 3°C along & across the charge under continuous

loading condition

k) Temperature controller accuracy : ±1°C

l) Furnace skin temperature: Maxi. 5°C above the ambient temperature is acceptable.

m) Exit Tube temperature:- Maxi 50 °C

n) Muffle material: To be decided considering maxi. furnace design temperature

4. Furnace Description:

The furnace shall consist of

1. Heating Chamber

2. Quenching chamber

3. Charging and discharging roller tables

4. PLC based control system with SCADA

5. Tube conveying system

6. Gas purging system

7. Chiller unit and other accessories, as required.

4.1 Heating zone:

a) Mode of heating :- Electrical

b) No of heating zones :- 3nos minimum. (With individual PID

Controller)

c) Effective length of the hot zone :- To be given by supplier (Min. 1.3m)

Heating zone shall consist of muffle, heating system, insulation brick lining, and outer

shell. The hot face of the heating zone should be well designed to hold firmly and

support the heating elements and shall be preferably of high of density alumina bricks

or any other insulating material.

4.1.1 Muffle of the furnace:

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Muffle of the furnace shall be designed suitably to provide a minimum life of 10 years.

Supplier has to specify the material, design and size of muffle. Supplier shall provide

material test certificate and QAP for approval at NFC. All the weld joints are to be

qualified through radiography as per ASME section VIII Div-I. Each weld joint shall be

radio graphed and corresponding films and certificates shall be submitted.

Muffle shall be suitable strengthened to avoid warping/distortion/bends.

4.1.2 Heating system:

Heating element:- To be specified by supplier

The heating element of the furnace shall be designed for continuous operation at the

set temperature. The furnace should be able to attain its working temperature within 8

hrs from room temperature. The power density inside the furnace shall be designed in

such a way that there is no temperature fall in any zone during charging of the

material. The final design of the heating element has to be approved by NFC before

fabrication and assembling. The electrical power of 415 + 10% V, 50 +2%Hz, 3-Phase

will be provided at a single point. Supply and laying of necessary cables is to be

included in the scope of supply. Supplier shall provide safety thermocouple in each

zone along with over temperature cut off facility.

4.1.3 Refractory and Insulation Brick:

The Vendor shall design refractory to restrict furnace skin temperature to maximum 5

degree above ambient at the maximum operating temperature.

Refractory brick material:- To be specified by supplier

Insulation brick material:- To be specified by supplier

Following points shall be taken care while designing refractory for the furnace:

a. The Support bricks over which heating muffle directly rests shall be single piece and

shaped bricks. No loose stacking of refractory bricks is allowed and should have

enough strength even at operating temperature.

b. The side structure for Support bricks, as far as possible, shall be integrated with

Support brick structure.

c. Refractory material shall be selected such that there is sufficient margin between

maximum service temperature of the refractory and actual temperature faced by

the material during operation,

d. The top cover should be two pieces with insulation pad to have the skin

temperature as specified with heavy duty lifting hooks for easy removal and re-

placement,

e. Provision for thermocouple points shall be provided at the center of the each zone

from top.

f. The inside refractory shall be designed to hold the heating elements horizontally

both at top & bottom.

g. The Supplier shall submit design of refractory system for approval before

fabrication.

h. Calibration of furnace during heating cycle shall be demonstrated by inserting

thermocouple inside the tube. Supply shall supply the survey thermocouple along

with sheath for thermocouple wire.

4.1.4 Outer shell:

The outer shell of the heating zone shall be designed suitably to accommodate required

refractory, the total load of the refractory, heating muffle, part of mesh conveyer belt

and charge during operation. The shell shall be made up of MS frame and plate with

heat resistant aluminum color painting. Required provision for heating element

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mounting and electrical connections shall be made. It shall be floor mounted, without

loading the retort.

4.2 Quenching zone

4.2.1 There shall be quenching zone immediately after the hot zone.

Quenching Medium:- Argon gas ( Supplier has to specify the specification of argon gas in

terms of contents) to be used.

Material of construction:- SS304L grade stainless steel with minimum 5mm thickness.

a) Quench rate:

Quench rate shall be enough to cool the biggest size of the tube within 1.5 minutes from

12000C to 4000C. Argon pressure shall be controlled automatically by means of a control

valve to an accuracy of ± 3%.

b) Quenching chamber:

The hot gas shall be collected uniformly from the top of the chamber through a water

cooled heat exchanger and header by means of blower. The out let gas of the top

header shall be cooled down by the evaporator and circulated back into the cooling

chamber by means of the blower through the common header. The rapid cool casing

shall be of gastight adjacent chambers. Two peep sights shall be incorporated at the

entry and exit point of chamber to enable viewing the charge. Supply should mention

the percentage of gas loss per hour during continuous operation.

c) Refrigeration Unit (If applicable) :

The refrigeration unit shall contain a condensing unit, an evaporator, necessary

interconnecting copper tubing etc. The refrigeration unit shall be designed, considering

the heat load from tube and conveyer belt.

1. Condensing unit:

Air cooled Condensing Unit for low temperature application

Accessories: Receiver, Stop Valves, Pressure switch, Electrical Box, Filter drier,

Sight glass, Solenoid valve, Thermostatic expansion valve, etc.

2. Evaporator/ Heat exchanger:

Type: Finned tube type gas (Argon) to water gas tight exchanger.

MOC: Copper for both fin and tube. The fin should be integral and not welded.

The rating/ capacity of evaporator shall suit the condenser unit.

3. Blower:

The capacity of the blower shall be sufficient enough to circulate chilled gas to cool

the maximum size of the ingoing tube within 1.5 minutes from 12000C to 4000C

during cooling from max operating temp. The RPM of the blower shall be regulated

by VFD to achieve different quenching rates as and when required. The blower and

shaft shall be hermetically sealed by means of Standard Mechanical seals to avoid

ingress of atmospheric gas into the system through the shaft sealing. Cooling

arrangement for seal shall be in-built in machine body. Interlock for positive flow of

coolant shall be provided to ensure cooling of sealing system.

Speed Control: Variable with VFD

Noise level: shall be less than 85 dB(A) at 1m, measured in free field.

Important Note:

Supplier should describe their design in the offer.

Note:- (i) Suitable thermal isolation is to be provided between hot zone and super

cooling zone.

(ii) Thermal profile of the furnace shall not be affected by the variation of

pressure of argon gas in the super-cooling zone.

(iii VFD rating should be atleast 25% higher than blower motor.

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4.2.2 Water jacketed cooling zone:

Immediately after quenching zone, water jacketed chambers in required numbers shall

connected to the zone by mean of flange and suitable gasket to prevent leakage of

atmospheric gas. Its purpose is to maintain the exit tube temperature as mentioned in

design basis.

Material:- SS 310 stainless steel sheet of 5mm thick minimum.

4.3 Charging & Discharging table:

Length of the charging and discharging table shall be minimum 7m each. Both charging

and discharging table shall be belt/roller driven and speed of the belt/roller shall be

synchronized in such a way that the linear speed at inlet and outlet shall be exactly

same. Charging table shall be supported by charging trough and that of discharging

table with collection trough. Size of charging trough and collection table should be

minimum 7m length and 500mm width. Tube from charging trough shall be loaded to

charging table manually. Tube from discharging table shall be unloaded to collection

trough by means of semi-automatic (push button type) unloading system or any other

suitable mechanism. Entire tube contact surface of the charging trough and discharging

trough shall be lined with suitable material like Teflon so that processed tube will not be

in contact with metallic part of the table in order to avoid damage during loading and

unloading. It should be equipped with sensors controlling positions of tubes.

Entry purge:- It should be designed to reduce the possibility of air ingress.

4.4 Control system:

4.4.1Electronics and instrumentation:

a. Temperature measurement shall be with R-type thermocouple with accuracy standards

conforming to ANSI 96.1 special accuracy. Two thermocouples per zone should be

installed and one for PID & another for Over Temperature Controller (OTC).

b. All thermocouples used in furnace shall be calibrated at intervals of 1000 C. Certificate

conforming to national standards shall also be supplied.

c. Independent Zone temperature control shall be implemented with aid of PID controller

and Digital AC power controller.

d. Survey thermocouples having sheathed cables of length equivalent to hot zone and

quenching zone for online calibration of the furnace shall be supplied in 10 Nos.

i. Specifications of PID controllers:

1. Dimensions : 96 x 96 mm

2. Input type :Universal (all TCs, RTD, 4-20 mA)

3. Output type : 4-20 mA

4. No. Of alarm : At least two.

5. Power supply : 90-230 V AC

6. Relay outputs : Two

7. Communication : MODBUS

ii. Specifications of Over Temperature Controllers:

1 Dimensions : 48 x 48 mm

2 Input type : Universal (all TCs, RTD, 4-20 mA)

3 No. Of alarm : At least one.

4 Auxiliary supply : 90-230 V AC (universal)

5 Relay output : One

iii. Specifications of AC power controllers:

1. Technology : Microprocessor based

2. Configuration : with PC and also with HMI mounted on unit.

Both options are required

3. No. Of phases : suitable for single or phase to phase.

4. Firing modes : Universal: Phase angle, Delayed Triggering +Burst

Firing, Soft start+ Phase Angle

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5. Current rating : Should be over rated at least by 25% than that of

maximum rated load of respective zone.

6. Features : With current limit & HB alarm.

e. Operations: All operations & necessary interlocks should be controlled with aid of PLC.

IO modules: With opto-isolation, 20% inputs/outputs per module

should be left unused as spares.

Adaptors : All special cables/adaptors required to make the

connection complete with PLC & PC shall be in the scope

of supply.

f. Data logging& HMI: Furnace should have a facility for data logging of minimum 30

days if worked on continuous round the clock shift basis. For data logging, report

generation and process mimics, a SCADA software interfaced with all Zone controllers,

PLC, dew point meter, belt speed indicator, gas flow rate, cooling water pressure and

other process parameters should be installed and running on an Operator panel / IPC.

It shall be possible to display the movement of the tube inside the furnace through

dynamic mimic. It should have fault finding provision with trend analysis etc. There

should be a facility of mirroring the SCADA data on separate hard disk.

Tags : 256, 20% more than total utilized tags, whichever is higher

Version : Latest at the time of delivery.

Type : Licensed development & run time both should be provided

for modification of project at a later date, if required.

Size of operator panel: 19”.

PLC shall be used for implementing the interlocks.

There should be a facility to back up the SCADA data on external hard disk.

g. Energy metering : Digital energy meter shall be provided. It shall have

communication facility & integrated with the SCADA.

h. Belt speed control: shall be implemented with VFD.

Integration : VFD output shall be used for actual speed indication which, in turn,

should be integrated with SCADA.

i. Supplier shall indicate total power consumption and required water and Argon supply

per hour

4.4.2 Electrical

a. Complete electrical circuit shall be designed for 415V +10%, 50Hz +2%, 3 phases, 3

wire system. All the required transformer shall be of dry type, single phase, 415V with

digital AC Power Controllers (Point no. 4.5.1-iii)

b. Meter: Each zone of the furnace shall have a digital ammeter, voltmeter and energy

meter. All the meters shall be of digital type and should be able to measure based on

true RMS measurement.

c. Motor: All motors shall be of TEFC squirrel cage induction motor of appropriate duty,

Class F insulation with single phase preventer(MPR preventer).

d. Transformer: All transformers (if any used) shall be of dry type and shall have the

following specifications:

Flux density: 0.8Wb/sq.m.

Insulation: > 100M ohm

The transformer shall be provided with lifting hooks and movable wheels.

e. Cable: All the cables shall be of 1.1kV grade Cu cables. Armored and unarmored cables

shall be used as per requirement. The supplier shall submit detailed test reports of all

the cables, switchgear and motors as per IS standards.

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f. Earthing: Suitable earthing with GI strip of 25x3, 50x6mm shall be laid out as and

where required and as per IS-3043 standards. Furnace and panels shall be provided

with double earthing.

g. Switchgear: Buttons/ LED indication lamps, etc shall be of M/s Siemens make only.

h. Panel:

i. The power and control panel of the main furnace shall be in a single panel with front

opening door, separated with a sheet steel.

ii. The panel shall have a panel incomer MCCB of greater than or equal to 800A rating

with adjustable trip set facility.

iii. Each zone of the main furnace shall have CBCT based E/F tripping mechanism of

suitable rating.

iv. The panel shall be made of CRCA sheet metal and shall be dust and vermin proof,

IP- 54 and as per IS standards.

v. Reputed panel manufacturers only shall carryout wiring and assembling of the

panel.

vi. The panel shall be have 10% extra space to meet any future requirement.

vii. The supplier shall provide GA and layout drawing of control and power panels for

approval before start of fabrication of panel.

viii. Emergency stop buttons shall be provided at suitable locations.

ix. It should have a AC of suitable capacity.

4.5 Tube Drive Mechanism.

The tube to be processed shall be conveyed through the furnace by means of a

conveyer mesh belt drive system. The conveyer mesh belt material shall be specified

by supplier. There shall be provision of stopper in regular interval at the edge of

the mesh belt, so that tube loaded on the mesh belt will never be out of the belt during

operation. The conveyer mesh belt shall be positive driven by AC motor with step less

speed variation. Supplier should ensure proper belt tensioning mechanism such that

belt should not sag due to thermal expansion. The mesh belt shall be run over idler

rollers of the muffle to avoid rubbing between belt surface and entire muffle surface.

Pitch of roller should be 200 mm or less. Designer shall ensure that the tube doesn’t

stop during the movement from entry to exit and should move in the required speed

without getting struck up due to obstacle or bending of tube due to temperature. It

shall also be ensure that tube doesn’t bend during the heat treatment operation.

4.6 Gas Purging system

The protecting atmospheric gas of the furnace shall be argon. It shall be provided as a

battery bank consisting of approx 150 kg cylinders. The argon gas bank shall be

installed around 10m away from the equipment. All the required piping, valves,

pressure gauge, flow control and measurement system are in the supplier’s scope. The

argon battery bank will be made available by NFC. Provision should be made for easy

fixing and dismantling of the argon battery bank via regulator/valve. Supplier has to

specify the argon consumption rate on continuous run basis

4.7 Chilling Unit (If any) :

Chilled water is to be used for cooling purpose and hence, suitable chilling unit shall be

provided to meet the requirement. 2 Nos of units shall be supplied with

interconnections in such a way as to ensure 1 in running and other as hot standby. NFC

will provide DM water at the inlet of the chilling unit. All necessary piping from chilling

unit to that of the furnace shall be in the scope of supplier. Water flow rate, pressure,

chemical quality requirements if any, etc; shall be indicated in the technical offer so

that same can by planned by NFC. The material of chilling unit shall be SS304L.

4.8 Thermal simulation and modeling:

Supplier shall carryout thermal simulation & modeling studies for both the hot zone as

well as the quench zone and submit the calculations and report the results for checking

by NFC before start of fabrication of the furnace. The studies shall include the effect of

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change of zone temperature, zone length, speed and argon pressure on variation of

job temperature along furnace length and similarly, variation of temperature with time

along the quenching chamber and effect of zone temperature, argon temperature and

pressure on quenching rate. If required, the supplier shall engage approved experts for

carrying out such studies.

4.9 Other requirements:

1. In addition to the above following requirements shall be incorporated in the equipment

a) Oxygen analysis: On line oxygen analysis of the furnace inside atmosphere with an

MDL of 1 ppm or less.

b) Dew point measurement:

Dew point of the atmospheric gas shall be measured online at least at two points.

One at quick/super cooling chamber and another at the out let of the dryer. The dew

point meter shall be able to measure up to -700C or better.

c) Water pressure sensor with alarm/indication

d)Furnace pressure sensor with transmitter for switching over to the full argon cylinder

or giving alarm in case of fall of pressure below given value.

e) Thermocouple to measure super-cooling zone temperature, argon temperature etc.

f) Water flow switches are to be used at all the water outlets from the furnace.

2. The design shall take care of thermal expansion of the furnace.

5 Scope of Supply:

5.1 Motor driven roller tables for charging and discharging with semi-automatic loading

and unloading of tube from the respective table. Rollers shall be of soft material.

5.2 Furnace body shall consisting of

a. Furnace chamber

b. Heating muffle

c. Electric heater assembly and wring

d. Refractory/ insulation brick work

e. Main drive conveyor equipment

f. Inlet and outlet hoods

g. Cooling muffle and jacketed sections for cooling water circulation.

5.3 Fast cooling section consisting of atmosphere gas circulation ducting, Circulating

fan, fin-coolers, chiller units etc.

5.4 Main electric control panel including instrumentation panel & associated I&C

components as described earlier in point 4.4.

5.5 Gas and water flow meter, flow switches, pressure switches etc.

5.6 Chiller unit.

5.7 Electric power will be provided at the main electric control panel. All

interconnecting power & control, cabling, earthing & other wiring between the

panels to the field, shall be in the scope of supply.

5.8 Compressed air required for the furnace will be provided at one location of the

furnace. All other piping for compressed air shall be in the scope of supply. The

maximum pressure of 6kg/cm2 compressed air will be provided.

5.9 All water piping for the fast cooling system and the slow cooling system are to be

included in the scope of supply.

6 Mandatory Spares

Firm shall quote for all the following components which are planned to be additionally

procured as spares along with the main machine. Cost of the following spares will be included

for comparison of offers:

a) Metallic mesh conveyor belt - 50 meters

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b) Heating muffle - 01 nos

c) Heating elements - 10 nos

d) Thermocouples - 2 Nos

e) Muffle gasket 4 Nos

f) Mesh belt drive system rollers - One Set

g) Self-tensioning mechanism for mesh belt drive

Note: If any of the above components is not used in the mill, firm need not supply the same.

However any other component performing similar function shall be given as spare. Item-wise

cost shall be quoted for all the above.

7 Inspection and Testing

7.1 PDI At Manufacturer’s works:

All required tests & inspections including the following will be carried out by the

purchaser at various stages of manufacturing and before dispatch and reports shall be

submitted:

a. Complete functionality and temperature accuracy of the furnace is to be demonstrated

at manufacturer’s works before dispatch. It shall confirm to the process parameters

and product quality as per the acceptance criteria in point-7.3 and as per furnace

design parameters point 3. It shall be demonstrated on Inconel alloy tubes of any two

sizes between 4mm to 10mm and 11mm to 25mm respectively. Supplier has to

arrange for the Inconel tubes at their works for hot trial. Wall thickness can be from

0.3mm to 3 mm. Supplier has to arrange the 100 kg of Inconel tubes of each size of

length 2m to 6m. Supplier has to demonstrate the temperature profile in the furnace as

per annexure 1.

b) Transformer: Routine tests & Type tests including temperature rise test, short circuit

current test, open circuit voltage test, test for flux density of 0.8Wb/sqm are to be

demonstrated as per IS standards.

c) Heating Element: Each heating element will be heated in open air by applying a voltage

that will cause them to dissipate rated surface loading of 5Watt/cm2 to reach uniform

temperature. Any black rings/ bands/ spots if found on the heating element after

attaining uniform temperature will be rejected.

d) Control panel: The control panel will be tested for full load at the supplier's site.

However, in the event of the supplier's inability to offer testing at full power, the same

will be carried out at NFC during commissioning trials. Any limitations/ defects

observed with respect to the performance of the components during these trials at NFC

will have to be replaced by the supplier at no additional cost and this shall be binding

on the supplier.

e) All thermocouples used in furnace shall be calibrated at intervals of 1000 C. Certificate

confirming to international standards shall also be provided.

f) Calibration certificates of used shall be provided.

g) The original test certificate of the refractory shall be provided by supplier conforming to

the following standards:

Sr.

No Standard Parameter

1 ASTM C201-93

(2013)

Thermal Conductivity

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2 ASTM C269-70 Permanent Linear Change (PLC) for castable

refractories

3 ASTM C24-

09(2013)

Pyrometric Cone Equivalent (PCE)

4 ASTM C583-10 High Temp. Modulus of Rupture (HMOR)

5 ASTM C133-97 Cold Crushing Strength (CCS) & Modulus of

Rupture (MOR)

6 ASTM C832-00

(2010)

Thermal expansion & creep of RUL

h) All the power controllers will be tested for their ratings mentioned on their respective

name plates at the supplier's site. In case the supplier is unable to provide required

test facilities, then these would be tested at NFC for the rated name plate capacity

during commissioning. Any limitations/ defects observed with respect to the

performance of the components during these trials at NFC will have to be replaced by

the supplier at no additional cost and this shall be binding on the supplier.

i) Chemical composition & IGC test certificate of the material shall be provided.

j) Hydro-test report of annular space of the water jacketed chamber shall be provided.

k) Dye penetration test report of all welds shall be provided.

l) All the weld joints of the muffle are to be qualified through radiography as per ASME

section VIII Div-I.

The manufacturer shall give at least 30 working days advance notice of the proposed

date of PDI.

7.2 At NFC after installation and commissioning

All required tests including following will be carried out:

a. Continuous operation at maximum working temperature for minimum 3 shifts

(General shift/day) with full load conforming to the process parameters and product

quality as per the acceptance criteria in point-7.3.

b. The job temperature uniformity along & across the charge under continuous loading

condition will be checked by 3 nos of survey thermocouples placed across the width

of the muffle. Supplier has to demonstrate the temperature profile in the furnace as

per annexure 1.

c. Skin temperature of the furnace shall be checked by RTD / Thermal Imaging

camera. ( Thermal Imaging camera will be made available by NFC)

d. Demonstration of entire operation through PLC.

e. Complete software shall be demonstrated at NFC, during trials, along with its un-

installation and installation.

f. Supplier should provide training for a minimum of four NFC engineers at NFC site for

operation and maintenance of equipment.

7.3 Acceptance Criteria:

The supplier shall demonstrate the following output rate & quality during

commissioning at NFC:

i. Output rate of annealing: 90 kg/hour for any two sizes between 4mm to 10mm and

11mm to 25mm respectively and 3000mm - 5000mmlength. Sizes will be selected by

NFC.

ii. Quench rate from 12000C to 4000C within 1.5 minutes

iii. The external and internal surfaces of the annealed tubes shall be bright with a

lustrous finish, free from any type of scale, patches, stain or any other mark. It will

be ensured that the feed tube is thoroughly cleaned without any oil stains.

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The above shall be demonstrated during performance trial after successful

commissioning.

8.0 Erection, commissioning and performance demonstration of equipment at purchaser’s site.

Erection & commission of the equipment is in the scope of the supplier. However, the following

shall be arranged by the purchaser during receipt, erection and commissioning of the equipment.

8.1 Unloading of the consignment

Will be carried out by the purchaser, However, packing list of the consignment along with weight

and dimensions of individual packages shall be submitted by the supplier immediately after the

dispatch of equipment.

8.2 Erection of the equipment

Erection works will be as follows. These works will be carried out by the purchaser in the presence

of responsible technical person of supplier.

- Unpacking and physical verification of all items as per packing list

- Positioning and integration of all sub assemblies. The tools and tackles required shall be

intimated by the supplier in advance.

- Grouting of all foundations. The foundation bolts, nuts and washers are to be supplied along

with equipment.

- Laying of all piping. Pipes and pipe fitting are to be supplied along with equipment.

- Laying and termination of electrical and instrumentation cables. Cables, cable accessories and

cable trays are to be supplied along with equipment. Electrical power will be provided by the

purchaser in the main incomer.

- Providing double earthing.

- All the utilities i.e. cooling water and compressed air will be provided at single point only. The

distribution of the same at different points shall be in supplier’s scope.

- Other points specific to equipment if any, may be included by the Indentor.

8.3 Commissioning of the equipment

Commissioning is to be carried out by the supplier. However, the following will be arranged by

the purchaser.

- The first fill of oils

- Shop floor work force for testing of sub assemblies and their integration

- General tools & tackles

8.4 Spares / items if any, consumed during the erection and commissioning of equipment until

completion of performance demonstration shall be arranged by the supplier.

9 Drawings and Documents

9.1 The supplier shall submit 3 sets of general arrangement drawings and detailed

engineering drawings of equipment, including sub systems, instrumentation, control

system piping etc. along with the design calculations for the heating elements/modules

within 6 weeks from the placement of order for purchaser's approval. The

comments/suggestions if any indicated by purchaser shall be incorporated and revised

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drawings shall be submitted. Fabrication can be started only after obtaining approval. All

approved drawings shall be provided as Soft copy in Auto CAD or pdf format.

9.2 In addition to the above following documents shall be provided as hard copies along with

delivery of the machine.

a) All electric schematic, wiring, cable layout, junction box diagram, circuit diagram

power, control panel layout etc.

b) Editable soft copy of PLC program and SCADA project.

c) GA drawing of control, power panel and heating element.

d) Complete part list indicating details of the switchgear- MCB/ MPCB/ Fuses, their Model

No (Bill of material).

e) The supplier shall provide approved drawings and electrical circuits as Soft copy.

*The above shall be as built incorporating all changes carried out during installation and

commissioning

9.3 Supplier shall provide equipment foundation drawings before 6 months of supply.

9.4 The supplier shall provide 3 sets of the following detailed documents along with

delivery to enable the purchaser to maintain, dismantle, reassemble and adjust all

parts of the equipment for carrying out maintenance work.

a) Electric circuit diagram in single line standard arrangements showing

nomenclature, symbols and other relevant information as well as diagram for

electrical circuit.

b) Instruction manuals including drawings for assembly and erection of all equipment.

c) Instruction manual for operation of all equipment.

d) Spare parts lists with engineering drawings, specifications and manufacturer’s

catalogues.

e) Bills of materials of all electrical, mechanical and instrumentation and control items

and software.

f) Individual wear out part Engineering Drawings along with material details.

g) List of Wearing Parts.

h) Specific instructions required for Preventive Maintenance Schedules.

i) Specific instructions for dismantling parts/subassembly, if any shall be brought

out explicitly.

j) Engineering drawings for Muffle, ladder, mesh belt rollers, mechanical seals etc.

shall be explicitly furnished.

k) Bearings list along with type, designation, quantity and location, shall be

provided.

9.5 On completion of successful performance trial, the supplier shall provide the following:

a) 4 sets of as built drawings incorporating all the changes and also soft copy.

b) 4 sets of operation, maintenance and safety manuals along with preventive

maintenance schedule and troubleshooting along with soft copy in compatible format.

10 General Requirement

The following are the general requirement of the specification.

i. The requirements specified in the tender are not exhaustive. The equipment and all

works shall conform in all respects to high standards of engineering, design and

workmanship and be capable of performing in continuous commercial operation up

to the supplier's guarantee in a manner acceptable to purchaser who will interpret

the meaning of drawings and specification and shall be entitled to reject any work

or materials which in purchaser's judgment are not in full accordance therewith.

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ii. Supplier has to provide detailed manufacturing schedule, QAP to the purchaser.

Actual manufacturing of the furnace shall be started only after obtaining approval of

QAP by purchaser

iii. If it is found at any stage that the equipment is not meeting the requirements of

specification, minor changes/rectification required shall be done at no extra cost to

the purchaser.

iv. The shade of paint for the equipment and painting procedure shall be approved by

purchaser.

v. All Power cables shall be routed through metal conduits. Power cables and control

cables shall be routed separately.

vi. Purchaser has the right to select the appropriate design and his decision will be

final.

vii. Supplier shall make his own arrangement for the welfare of his personnel and their

stay during the erection and commissioning period.

viii. Tools, tackles instruments & consumables etc required for erecting commissioning

and successful performance trial shall be brought by the supplier on a returnable

basis.

11.0 Safety and Interlocks

11.1 Safety

The Furnace should meet requirements of all latest codes and applicable standards including electrical, fire and safety standards. a. In all modes of operation; automatic, manual & maintenance, safety of the furnace

shall be ensured during power interruption or in case of emergency stop. A key lock shall be provided for the maintenance mode.

b. Welding shall be carried out by welders qualified in accordance with latest version of the ASME section VIII Div-I. The Weld Procedure Specification (WPS), Procedure Qualification Record (PQR), and Welder Performance Qualification (WPQ) shall be included in the documents provided by the manufacturer.

c. Details of interlocks for safe & smooth functioning of the furnace & its sub systems shall be provided. During normal operation, the protection of equipment as well as job, against malfunctioning shall be ensured by the manufacturer.

d. Audio-visual alarm and the levels of the alarms shall be defined by the manufacturer in order to ensure safe operation of the furnace.

11.2 Interlocks:

The furnace control shall have interlocks for thermal cycle, cooling system, etc. and other safety features for protection of the equipment, its sub systems as well as the job. The manufacturer shall provide the complete list of interlocks in the offer. Typical interlocks required are

Over-shooting of temperature in the furnace

Inadequate water flow

Low water pressure

Inadequate compressed air pressure

Interlock for control atmosphere gas All the instruments required obtaining the above signals to PLCs such as level switch, pressure switch, flow switches, thermo-couples etc. shall be included in the offer.

12.0 Acceptable Makes

13

Sr

No

Components /

subsystems

Makes

1 Condenser Unit Danfoss / Emerson / Tecumseh/Daiken

2 Blower Nadi / Flakt / Accel /Kruge/ Nicotra.

3 Mechanical seal Eagle / Burgmann / John Crane / Flow Serve

4 Chiller Voltas/Blue Star/ Carrier/ York

5 PID controller Eurotherm/YOKOGAWA / Honeywell

6 OTC Eurotherm/ASCON/YOKOGAWA

7 AC Power controller Eurotherm / AEG

8 PLC SIEMENS s7-300 / Schneider

9 SCADA WINCC Flexible / Schneider

10 Energy meter CONZERV / Enercon / Fluke

11 Industrial PC Advantech/SIEMENS

12 VFD SIEMENS / ABB

13 Ammeter / Volt Meter AEPL / MECO / AE or equivalent imported make

14 Motor SIEMENS / IEC / Kirloskar

15 Cable CC/ UNIVERSAL / RPG / FINECAB / GEM / FINOLEX /

L&T / Anchor/ Havells or equivalent imported make

16 Switchgear SIEMENS

17 Dew point meter GE-sensing / Testo / SHAW SUPER DEW

18 Oxygen Analyzer SHAW / Orthodyne

19 Refractory

Horizon / CUMI / AZARAKHSH or equivalent imported

make

20 Electrical Panel/

cabinet

Rittal

21 Pressure Switch Indfos/ switzer/ forbes marshal

22 Flow Switch IFM/ TRAC

NB: Approval required by NFC for different makes other than specified and any quality test

required shall be carried out by the supplier at no extra cost.

13.0 Bidders Qualification Criteria.

a. The bidders shall have past experience in design and manufacturing of continuous

furnace (>/= 10500C) with reduced/inert atmosphere for annealing followed by gas

quenching of steel tubes of length 4m or above, or any other product, without

which the offer is liable for rejection.

b. Bidder should have experience in designing of a continuous furnace for more than 5

years.

c. Bidders shall provide documental evidence if asked for of their past experience in

successful manufacturing of similar control atmosphere furnace and continuous

feeding systems, in the Part-I offer along with details of the previous order

executed.

d. The party shall facilitate purchaser’s visit if asked for to their customer site to whom

they have supplied such furnace and working satisfactorily for evaluating the

performance.

e. The bidders shall have executed a single order of more than 5 crores for similar

equipment.

14.0 Terms & Conditions.

a) Bidders have to provide detailed calculations for achieving specified quench rate along

with their offers.

b) The price comparison of technically suitable offers will be based on total cost of the

basic equipment along with mandatory spares.

c) The bidder shall submit their un-priced price bid along with part-I offer.

14

d) Deviation to technical specifications and terms & conditions, if any shall be clearly

brought out in the part-I offer, without which offer will be considered as incomplete.

e) A compliance statement of the technical specifications of the furnace tendered versus

the furnace being offered shall be enclosed along with technical offer.

15

Annexure 1

Sample Survey Temperature profile

1150°C

600°C

Temp

°C

400°C

60 sec 400 sec 90 secs

Room <50°C

temperature

Time