section-v-technical specification 20130610 103851

8/18/2019 Section-V-technical Specification 20130610 103851

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E-Tender n o. 8000005410

TECHNICAL BID DOCUMENT

FOR

MRS & DRS


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SCOPE of SUPPLY, WORK & TECHNICAL SPECIFICATION

for

Annual Rate Contract

for

Above-Ground Skid mounted (inside cabinet), Twin Stream District

Regulating Station (DRS) & Metering Station (MRS) with Filtration

and Pressure Regulation for Natural Gas Application


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CONTENTS

1.0 GENERAL

2.0 SCOPE OF SUPPLY, WORK & BIDDER’S RESPONSIBILITY

2.1 Scope of work2.2 Scope of supply2.3 Scope of Work & Supply

3.0 DESIGN PHILOSOPHY

3.1 General3.2 Codes & Standards

3.3 Instrument Design Criteria3.4 Junction Boxes & Cabling Philosophy

3.5 Instrument Painting Requirements

4.0 PROCESS DESCRIPTION

5.0 JOB SPECIFICATION

6.0 TESTING AND INSPECTION

7.0 DOCUMENTATION

8.0 MISCELLANEOUS

9.0 SHIPPING & PACKAGING

10.0 PERFORMANCE GAURANTEE

11.0 INSTALLATION & COMMISSIONING

12.0 BIDS

13.0 MANDATORY SPARES

ANNEXURES

Annexure -1 - Special Instruction to bidderAnnexure -2 - Bidder Scope of Supply & InstallationAnnexure -3 - Schematic line diagram/ Typical P & IDAnnexure -4 - Approved Vendor ListAnnexure -5 - Quality Assurance PlanAnnexure -6 - Data Sheet of Skid Components/ Equipment

Annexure -7 - Technical QuestionnaireAnnexure -8 - Standard Specifications of Equipment & Technical

RequirementsAnnexure -9 - FAT Procedure/ FAT ManualAnnexure -10 - PMS

Annexure -11 - CHECK LIST (TECHNICAL)Annexure -12 - Checklist for evaluation of BEC-TechnicalAnnexure -13 - Standard Register List in Flow computers for SCADAAnnexure -14 - Bidder’s Data Requirement


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JOB SPECIFICATION, SCOPE OF SUPPLY, WORK & TECHNICAL SPECIFICATION

1.0 GENERAL:

i) This bid document is for Annual Rate contract for supply of DRS & MRS and covers requirement andspecification of “Above ground Skid mounted, twin stream District Regulating Station (DRS) and Turbine

flow Meter / RPD flow Meter Based Metering Station (MRS), mounted inside Cabinet”.

ii) The specification provided in bid document, together with all Annexure enclosed covers the requirement for thedesign, engineering, manufacturing, testing, inspection & supply of MRS/ DRS along with all accessories for

various site/ location as per the schematic line diagram/ typical P & ID, Technical specifications, datasheets

provided in the bid document.

iii) This is a NO Deviation tender. Any deviation to tender condition/ job specification/ technical requirement of biddocument, shall lead to rejection of bidder’s offer/bid. Compliance with Technical Specification will be taken for

granted, if during bid submission, deviations are not specifically mentioned in format provided in tender.

iv) For DRS (SOR Items- 1 & 2), the scope of work/ supply includes Design, Engineering, Manufacturing, Inspection,

Testing and Supervision for Installation & commissioning of DRS consisting of twin streams of Filtration andPressure Reduction system along with all the accessories and valves, piping, instruments & fittings as perschematic line diagram and P & ID’s.

v) For MRS (SOR Items- 3 to 8), the scope of work/ supply includes Design, Engineering, Manufacturing, Inspection,Testing and Supervision for Installation & commissioning of Metering Skid consisting of twin streams ofFiltration, Pressure Reduction system, flow measurement (through Turbine flow Meter / RPD Meter) includingField mounted Flow Computer with Data Logger (for SOR Items- 4, 5, 7 and 8) / inbuilt field mounted EVC (forSOR Items- 3 and 6), Solar panel, Battery along with all the accessories and valves, piping, instruments & fittings

as per P & ID’s and schematic line diagram.

vi) The Design, Required capacity, Pressure Rating of the Skids shall be as per schematic line diagram/ typical P &ID’s provided with this document.

1.1 Description and requirements contained in the tender specification are concise by necessity and cannot include all the details.However, it is the responsibility of the bidder to execute the job on turnkey basis in accordance with the specifications andinternationally recognized good engineering practices.

1.2 Any activity which are not specifically listed/ mentioned in the bid document, does not absolve the bidder of theirresponsibility to include such activities in their scope of work and supply, which otherwise is necessary, to meet technicalrequirement of bid document and to complete instrumentation & mechanical work for the project.

All such activities which are not specifically in the tender document shall also be carried out by the bidder to meet the tenderrequirement/ job requirement without any cost & time implication to GAIL.

1.3 In the event of any conflict between these specifications, related standards and codes, any other attachment to this package,

the bidder shall follow the following documents in the order of their priority:

a) Job Specifications for Gas metering package b) Data Sheets and Typical P&IDc) Technical Specification attached in the tender document.d) Standard specifications

In case of any conflict in various documents, same shall be referred to GAIL for clarification. Bidder shall not proceedwithout getting written approval in such a case.

2.0 SCOPE OF WORK & BIDDER’S RESPONSIBILITY

2.1 Scope of Work

Salient features of DRS and MRS skids envisaged under rate contract are as under.

(a) SOR Items-1 & 2: District Regulating Station (DRS), 300# pressure class rating (entire skid inlet & outlet), which shall be

twin-stream skid mounted (inside cabinet).


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(b) SOR Items-3 to 5: MRS will comprise of Metering, Filtration and Pressure reduction section. It shall be Skid mounted(inside cabinet) having pressure class rating of 300# (skid inlet) / 150# (skid outlet). Flow meters for these SOR items shall be as per P&ID/ schematic line diagram.

(c) SOR Items-6 to 8: MRS shall be designed for pressure class rating of 150# and shall comprise of Metering, Filtration andPressure reduction section, which shall be Skid mounted (inside cabinet). Flow meters for these SOR items shall be as per

P&ID/ schematic line diagram.

(d) Electronic Volume Corrector (EVC) installed on RPD Meter is acceptable for SOR Item-3 & 6 only. For rest of the MRSskids, field mounted Flow computer is envisaged.

(e) Turbine flow meter is envisaged for SOR Items-5 & 8. For rest of MRS skids (SOR Items- 3, 4, 6 & 7), RPD flow meter is

envisaged.

2.1.1 The scope of supply and works shall include, all the activities of project management, design, engineering, training, factory

testing, supply, installation, commissioning, site testing, test run, quality assurance and quality control of the system, and

documentation with the turnkey responsibility and meet the requirements, its objectives, functional and specific requirementsdescribed in the specifications and taking care of complete requirements.

Bidder shall be responsible for execution of the package on turnkey basis with scope of work, scope of supply, P&ID and job

Specifications attached in tender but not limited to the following:

i) Design and Engineeringii) Procurement and Supply of bought out items,iii) Inspection, Factory testing and Acceptance

iv) Supervision for Installation, field calibration, testing and commissioning

2.1.2 Performing all works required for designing, engineering, testing, supply, installation, interfacing with the communicationchannels, commissioning (with supply of commissioning spares including consumables), site testing, test run and putting into

operation of the system complete in all respects.

Bidder’s Scope of supply & work includes design, engineering, technical requirement for design, engineering, procurement

of items/ skid components, manufacturing, construction features, assembly, testing & inspection, commissioning of skids

(DRS/ MRS) being procured under rate contract.

2.1.3 The scope of supply and works shall include all the activities required for design, engineering, procurement of bought outitems, manufacturing, assembly, factory testing, supply, installation, commissioning, site testing, test run, training, quality

assurance, quality control of the system and documentation with overall responsibility to meet the tender requirements, itsobjectives, functional and specific requirements described in the tender specifications, technical requirements and

satisfactory performance.

2.1.4 Scope of supply and works also includes packing, forwarding (suitable for storage/ preservation at site), loading, unloading,transportation and transit insurance for delivery of skids at GAIL’s site/stores. Storage and preservation of skids at site is inthe scope of GAIL. However Skids shall be supplied in such a way that the skids are suitable for outdoor installation, properstorage & preservation.

2.1.5 The DRS and MRS shall be manufactured as per all the requirements of PNGRB Technical Standard T4SE, as per thetechnical specification, other relevant standards and statutory requirements. All other relevant standards and requirementsshall also govern design and engineering of DRS and MRS. Bidder shall seek clarification (if any) in this regard before bid

submission. After submission of bid and post award, NO deviation to tender condition shall be entertained. Unless otherwise

specified, the latest edition of the standards mentioned herein this specification, including all addenda and revisions, shallapply.

2.1.6 The design, manufacturing & fabrication of DRS & MRS skids shall be such that each of its equipment / component is easilyaccessible, operable and maintainable and the same shall not obstruct the operation and maintenance of any other skidcomponent/ equipment or part thereof. Unless otherwise specified, the pressure indicated in this tender document is gauge

pressure.

2.1.7 Bidder’s scope of works includes supervision for installation and commissioning of entire skid package, as per the scope ofSupply and Works.

2.1.8 Bidder shall Furnish as built documentation, drawings, reports, certificates and other information required here-in including

operation and maintenance manuals of all the equipment/ skid components.

2.1.9 Type, Make and model number of all components of DRS / MRS shall be mentioned clearly in the bidder’s offer. Biddershall also submit sizing calculation, Cv/ Cg value of offered regulator & slam shut valve, pressure drop calculation across


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filter, performance curve and specific technical catalogue (in English language only) of the models offered in their technical bid.

2.1.10 DRS and MRS shall be designed for following design conditions and Process parameters:

Self-actuated Regulators (PCV) and SSV of DRS & MRS shall be pilot operated. Direct acting pressure regulators / SSV is

NOT Acceptable.

(a) DRS (SOR- 1 & 2) – Design Condition :

DRS shall be designed for pressure of 49 Kg/cm2g. Differential pressure (across DRS) shall be 3 Kg/cm2g or lower.

Monitor regulator with Integral Slam Shut valve is acceptable. However, bidder can also offer independent Regulator andSlam Shut valve.Inlet and outlet (delivery) pressure is being provided separately for each individual SOR items.

(b) MRS envisaged for SOR- 3 to 5 shall be designed for:

Design pressure of Inlet of MRS (up to PRS): 49 Kg/cm2g

Design pressure of outlet of MRS (PRS downstream): 19 Kg/cm2gMaximum differential Pressure across entire MRS skid shall be 2 Kg/cm2g

Regulators (PCV) and SSV shall be pilot operated.Monitor regulator with Integral Slam Shut valve is also acceptable.

Spring range of offered PCV/ Regulator shall be : 1 to 5 Kg/cm2g (Spring range shall be used for selection / supply of Pilot

for PCV and shall be supplied with skid)Spring range of SSV/ CRV shall be 1.5 to 6 Kg/cm2g.Inlet and outlet (delivery) pressure provided elsewhere shall be used for sizing of piping of individual skid(s)/skid componentFor sizing of Regulators and SSV, skid delivery pressure (provided elsewhere in tender) shall be used.

(c) MRS envisaged for SOR-6 to 8 shall be designed for:

Design pressure of MRS (Inlet & Outlet): 19 Kg/cm2g

Maximum differential Pressure across entire MRS skid shall be 2 Kg/cm2gSet point/spring range of offered PCV/ Regulator : 1 to 5 Kg/cm2gSSV/ CRV shall be sized, designed, considering set point/ spring range of 2-6 Kg/cm2g.

Monitor regulator with Integral Slam Shut valve is also acceptable for SOR-6 to 8.

Inlet and outlet (delivery) pressure shall be used for sizing of skid/ its component and is provided separately for individualSOR items (For sizing of Regulators and SSV, skid delivery pressure shall be used).

(d) DRS & MRS shall be designed considering following process parameters i.e. Flow rate, Inlet & outlet (delivery)

Pressure. Minimum size & rating of skid / components selected & offered shall be as indicated below. Offered size shall

be same or higher that the sizes indicated below.

(i) For SOR Item-1 :

Flow Rate : 200-2200 SCMH

Inlet Pressure (range) : 16 - 49 Kg/cm2gOutlet Pressure range : 4 - 8 Kg/cm2g (shall be set at 5.5 Bar pressure)

Minimum size of main line inlet valves/ pipe (upto PRS inlet) : 2”, 300#Minimum size of main line valves/ pipe (downstream of PRS) : 4”, 300#

Minimum size of SSV / Regulator : 1”

(ii) For SOR Item-2 :

Flow Rate : 500-5000 SCMHInlet Pressure (range) : 16 - 49 Kg/cm2gOutlet Pressure range : 4 - 8 Kg/cm2g (shall be set at 5.5 Bar pressure)

Minimum size of main line inlet valves/ pipe (upto PRS inlet) : 3” 300#Minimum size of main line valves/ pipe (downstream of PRS) : 6” 300#Minimum size of SSV/ Regulator : 2”


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(iii) For SOR Item-3 :

Rated Flow Rate : 500-5000 SCMD

Inlet Pressure (range) : 5 - 45 Kg/cm2gOutlet Pressure range : 2 - 5 Kg/cm2g (shall be set at 3 Kg/cm2g pressure)Minimum size of main line inlet valves/ pipe (PRS inlet) : 1” 300#

Minimum size of main line valves/ pipe (downstream of PRS) : 2” 150#

Required G-Rating and size of RPD flow meter : G 65, 2”, 150#

(iv) For SOR Item-4 :

Rated Flow Rate : 1,500-12,000 SCMD

Inlet Pressure (range) : 5-45 Kg/cm2gOutlet Pressure range : 2 - 5 Kg/cm2g (shall be set at 3 Kg/cm2g pressure)Minimum size of main line inlet valves/ pipe (PRS inlet) : 1.5” 300#

Minimum size of main line valves/ pipe (downstream of PRS) : 3” 150#Required G-Rating and size of RPD flow meter : G 160, 3”150#

(v) For SOR Item-5 :


Inlet Pressure (range) : 6 to 45 Kg/cm2gOutlet Pressure range : 2 to 5 Kg/cm2g (shall be set at 3 Kg/cm2g pressure)

Minimum size of main line inlet valves/ pipe (PRS inlet) : 2” 300#

Minimum size of main line valves/ pipe (downstream of PRS) : 4” 150#Required G-Rating and size of Turbine flow meter : G 250/ 400, 4” 150#

(vi) For SOR Item-6 :

Rated Flow Rate : 400-3600 SCMDInlet Pressure (range) : 4 to 8 Kg/cm2gOutlet Pressure (range) : 1.5 to 4 Kg/cm2g (shall be set at 2.5 Kg/cm2g pressure)

Minimum size of main line inlet valves/ pipe (upto PRS inlet) : 1”150#Minimum size of main line valves/ pipe (downstream of PRS) : 2”150#Required G-Rating and size of RPD flow meter : G 65, 2”, 150#

(vii) For SOR Item -7 :

Rated Flow Rate : 1,600-16,000 SCMDInlet Pressure (range) : 4 to 8 Kg/cm2g

Outlet Pressure (range) : 2.5 to 4 Kg/cm2g (shall be set at 3 Kg/cm2g pressure)

Minimum size of main line inlet valves/pipe (upto PRS inlet) : 2”150#Minimum size of main line valves/ pipe (downstream of PRS) : 3”150#Required G-Rating and size of RPD flow meter : G 160, 3” 150#

(viii) For SOR Item-8 :


Inlet Pressure (range) : 5 to 8 Kg/cm2gOutlet Pressure (range) : 2 to 4 Kg/cm2g (PCV shall be set at 3 Kg/cm2g pressure)

Minimum size of main line inlet valves/ pipe (upto PRS inlet) : 2”150#Minimum size of main line valves/ pipe (downstream of PRS) : 4”150#

Required G-Rating and size of Turbine flow meter : G 250/ 400, 4” 150#

2.1.11 GAIL reserves the right to accept / reject the offer of bidder based on the past performance of their product(s) supplied in

GAIL, or elsewhere. Bidder to compulsorily submit report on satisfactory performance of completed/ executed orders by bidder indicating satisfactory working for minimum 6 months period.

2.1.12 Design & Engineering :

(a) The bid package consists of typical Piping & Instrumentation Diagrams, process data sheets and technicalspecification of individual skid items/components. The bidder shall be responsible to carry out the design and

detailed engineering based on the data provided in the bid package and in line with other technical requirements

specified elsewhere in bid document. Scope shall also include sizing and verification for all items including wheredata is dependent upon detailed engineering. Scope of supply/ work also includes detailing of basic engineeringdesigns, preparation of data sheets, drawings for instruments and system oriented items, engineering drawings etc.


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(b) Residual Engineering

The bidder shall also be responsible for carrying out any residual basic engineering necessary for detailedengineering like equipment/ instrument sizing, utility consumption, specifying derived data in process data sheets,type and material selection of instruments/ equipment wherever required.

(c) Engineering Drawings & Documents

i) Vendor Data Requirements indicate the list of drawings and documents required to be supplied by the bidder, as minimum. Bidder to note that the list specifies only the major deliverables. Documents and

drawings not listed but necessary for proper engineering, construction, operation and maintenance shall

also be prepared by the bidder.

ii) Bidder shall be responsible for preparation of all engineering drawings and documents including thosenecessary for construction like instrument index, tray layouts, location plans, cable schedules, installationstandards, bill of material etc.

iii) Bidder shall also be responsible for providing all drawings and documents for package/ sub packageunits.

iv) It is expected that the bidder utilizes uniform data sheet formats enclosed along with this bid document,for preparing specifications for various instruments, equipment and skid component including those,which are being prepared by package/ sub package vendors. Items for which no format has been attached

with the document, bidder may use standard ISA formats. Use of manufacturer standard formats shall beavoided.

v) The bidder shall supply all the documents in both hard copy and soft copy. This includes all thedocumentation including those for package units.

d) The scope for “design and engineering” shall also include review of post-order vendor drawings and documents forall equipment/ instruments and system oriented items. Following methodology must be followed for drawings and

documents being forwarded to GAIL.

i) The Bidder shall thoroughly review and approve their vendor drawings for all equipment/instruments

including sub-package items, before forwarding to GAIL. Only approved drawings duly signed and

stamped by a competent and authorised representative/ engineer of Bidder shall be forwarded.

ii) The Bidder shall be responsible for all System Engineering documents for the Gas metering systems.This shall include all related documents such Functional design specifications, sizing calculations,

pressure drop calculation etc. and Engineering documents such as functional loop schematics,

instrument details and cable schedule, Power supply distribution schemes etc. These documents shall bereviewed and approved by Bidder based on philosophy specified/ agreed for the engineering beforeforwarding to GAIL.

iii) All multidisciplinary fabrication and construction drawings shall be reviewed and signed by bidder’s

representatives before forwarding to GAIL for review/ approval/record.

e) Bidder shall be fully responsible for co-coordinating with all agencies concerned to ensure proper, uniform andsmooth engineering. This shall include coordination with:

i) All individual item suppliers for uniformity in engineering and documentation supplied by them

including P&ID’s, instrument specifications, installation standards etc. and obtaining all requisitedrawing and documents for review, record and final documentation.

ii) All instrument item suppliers including suppliers/ manufacturers of various system oriented items.

iii) Bidder’s own inter-departmental coordination with departments like mechanical, piping, electrical, QC,

pressure vessel, heater group etc. This shall include furnishing all necessary engineering data in the formof drawings & documents and review of drawings & data supplied by other departments.

f) Bidder shall be responsible for preparation of all As-Built drawing / documents including.

i) All P&IDs, GADs, Foundation drawing

ii) All Datasheets, sizing calculation, specifications of instruments

iii) All Purchase documents.iv) All System documents including hardware and software documentation.


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2.1.13 Procurement & Supply of bought out items, Factory testing and Acceptance

a) Engineering for procurement & supply of bought out items, shall include preparation of various materialrequisitions which shall include process data sheets, typical data sheets for equipment/ instruments, instrumentstandard specifications, special requirements etc., evaluation of offers received from various manufacturers/ sub-

vendors, preparation of Technical Bid Analysis, preparation of purchase requisition and review/ approval of sub-

vendor drawings, incorporation of GAIL’s comments. Installation of all the loose supplied items, itsinterconnection etc shall be in the scope of supplier. In case of any dispute / conflict arising due to difference inopinion/ interpretation, the interpretation of GAIL shall be considered final.

b) All Equipment/ Instrument items/ skid components shall be procured from vendor list attached elsewhere in this

package. Bidder must desist from procuring any items from vendor(s) not approved by GAIL. Along with the bid,the bidder has to provide the list of items/ equipment with size, Make and Model Number selected only form theapproved vendor list provided in the bid document. Non-compliance to this may result into rejection of bid.

c) Bidder shall prepare Bill of Material, purchase requisitions for all equipment/ instruments/ systems which shall

consist of a consolidated purchase document including all purchase specifications including data sheets, sizingcalculation, dimension details, special instructions/ requirements (if any), standard specifications/ purchase

specifications, testing requirements, quality requirements etc. All purchase requisitions shall be furnished to GAILfor information/ review/ approval as applicable.

d) Testing & calibration of all instruments, Factory Acceptance Test (FAT) and Site acceptance Test (SAT) shall be

carried out by the bidder. Range/ calibration span, set points, reports etc shall be modified as per GAIL requirement

by the bidder during FAT and SAT. GAIL shall witness testing of any or all items at various stages duringmanufacture and/or at final stage before shipment at their discretion. Testing shall be carried out as per approved procedures. No instrument shall leave manufacturer’s works without factory acceptance test. All necessary changesshall be incorporated/ implemented as suggested by GAIL during FAT/ SAT etc. As build drawing, final technical

documentation shall be submitted by the bidder. It shall contain all such changes.

e) The skid has to be transported to site in different modules. Individual modules shall be so designed that there areno/ minimum cabling interconnections between various modules and such interconnections (if any) shall be in the

bidder’s scope.

f) The quoted man-day rate for installation supervision and commissioning of skid (as per schedule of rate) shall be

valid for 24 months from date of issuance of FOI. Bidder shall depute qualified and competent person for

installation supervision / commissioning.

g) Testing & Calibration: Bidder’s scope of work includes testing of all supplied items and systems including impulse lines, pneumatic

signal tubes and instrument cables and special instruments/ items if any. Bidder shall also carryout testing and

calibration of all instruments as per the requirements specified elsewhere in tender document. Testing andcalibration of Gas metering system shall be as described elsewhere in the document.

h) Commissioning: It is the responsibility of Bidder to co-ordinate and make available the services of vendors/ sub-vendors for gas

metering system package, control system, etc. and other special instruments/ equipment like Gas flow meters, Flowcomputers, Pressure regulators, testing, FAT, Site acceptance, start-up/ commissioning of the station. The bidder

shall provide assistance during commissioning without any condition/ pre-requisite. It is the responsibility of thevendor to get the certification from site Engineer.

2.1.14 Installation, Field Calibration, Testing and Commissioning

a) Bidder shall carryout installation of all instruments in the skid as described in this document. Installation shallinclude but not limited to installation of all supplied items, installation skid assemblies explained in this package,installation of junction boxes, interconnection between instruments and junction boxes, fabrication, laying and

painting of cable trays, laying of all single pair and multi pair cables in the skid, JB earthing/ grounding, FieldInstruments/ signal earthing/ Grounding, tagging, ferruling, cable glanding and pair/ core identification of all field

cables.

b) Distribution of power to various instruments in the skid from single point in the skid. Separate JB is required for

different type of signals and also for power to field instruments (Power supply to Meter, transmitters and otherField Instruments shall be provided through separate JBs).

c) Installation shall be carried out as per GAIL standards or as recommended in the tender. For special instruments,

the installation may be carried out as per vendor/ manufacturer’s recommendations however all such installationstandards shall be subject to GAIL review.


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d) Bidder’s scope of supply/ work shall include earthing cable/ strips (as applicable) etc. (along with cable tray withsupports for installation) in the skid/ JB/ control room, as per the requirements of various instruments.

e) Junction boxes and cable glands (as per the requirement of area classification) for different types of signals such asintrinsically safe, alarm, power etc. should be supplied and mounted/ installed in skid. Preferably, all JBs shall be

mounted in skid at height of 1.3 meter from ground/ finished floor level/ skid base frame and accessible /

approachable from outside. JBs shall not to be installed inside Skid.

f) Painting of pipes, equipment, instruments, enclosures, platforms, jump-overs/ crossovers, as required; in line withthe painting specifications attached elsewhere in this document.

g) Suitable environmental enclosure for custody transfer field instruments for environmental effect protection with a provision of locking. Any other erection material required for installation and commissioning of skid/ instruments.

h) Any special tools/ tackles required shall be in scope of vendor.

i) Galvanised iron/ copper earthing strip and earthing cables for earthing of all instrumentation items including junction boxes etc. to instrument earthing system. Supply of earthing strip / cable is in bidder’s scope. Earthing pit

at a distance of 20 meters shall be considered for supply of cable/ other items.Making of earth pit and laying of earthing cable/ strips is not in bidder’s scope.

j) Platforms & cross-over(s) / Jump-over(s) shall be provided for the operation and maintenance of the equipment/

instruments/ JBs installed in the skid. Proper spacing shall be maintained between the equipment for operation &

maintenance. The vent & drains in skid shall be provided with proper support. All the vents shall be at a height ofminimum 3 meters above the working platforms. All flanges shall be connected through flexible jumpers ofMinimum 3 mm thickness and 20 mm wide copper strips.

k) All the software used in the system and as specified elsewhere, shall be licensed in the name of GAIL.

l) Compulsory spares and commissioning spares (for each skids separately) as listed elsewhere in this document.

m) Drawings and documents as listed elsewhere in this document.

n) All pipes, tubing, fittings, valves, gaskets, bolts, nuts, spades, etc., within the skid battery limit.

o) A structural skid complete with necessary drip pan, walkways, staircase, platforms, gratings, handrails for accessfor operation and maintenance.

p) Earth bonding system and earthing boss.

q) Lifting lugs and spreader beam / frame, foundation Anchor bolts for the skid.

r) Stainless steel nameplate for each skid, each tagged equipment and component.

s) All Tie-ins (flanged connections) with nuts and bolts.

t) Inlet and Outlet matching flanges and Studs & nuts shall also be supplied along-with the skid.

u) Sun/ rain protection shed for electronic instruments/ FC shall also be supplied by the bidder.

v) Operation and maintenance manual for instruments/ equipment, as built drawing/ documentation.

2.2 SCOPE OF SUPPLY

2.2.1 Supply of all items as indicated in the typical Piping & Instrumentation diagrams (P&ID) / Schematic line diagram and othertechnical documents & specifications attached along with the bid document.

The scope of supply shall be as per the typical P&ID attached and shall include but not limited to the following as aminimum:

a) Skid mounted Custody transfer Gas metering system package (MRS) inclusive of Filtration, Pressure let down skid& Gas metering (through Turbine flow Meter / RPD flow Meter ) complete in all respect as per P & IDs, Process

data sheets & as described in Job specification for Gas metering system package for SOR Items 3 to 8. For SOR

Items 1 & 2, DRS (District regulating station) shall be skid mounted and shall include Filtration & Pressure let


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down skid complete in all respect as per P & IDs, Process data sheets, Job specification, technical details and otherdetails described in bid document.

b) Suitable Weather-proof cabinet for Skids with louvers for ventilation, doors, (with slanted top, checker plate bottom) as specified in tender.

c) All equipment/ field instruments such as Filters, valves, Pressure Transmitters, Pressure Gauges, Temperature

Gauge & RTDs, Pressure Control valves, Slam shut valves, Pressure relief valves, flow meters, FCV, on-lineBattery operated field mounted Flow Computer / EVC, JB, Solar power system, Battery etc. EVC is acceptable forSOR Items- 3 and 6. For balance MRS, Field mounted flow computer is envisaged.

d) GSM and GPRS Modem shall be provided with each Flow Computer for remote data configuration, remote data

uploading (previous 35 days data) and remote data monitoring.

e) All installation and erection materials such as impulse tubing, piping, pipe fittings, valves, tube fittings, cable,

cable tray and supports, foundation bolts of the skid, gaskets, companion flanges for inlet and outlet of the skid, alltype of consumables and accessories for mounting of instruments, instrument supports, tray supports, canopies/

sunshields for all field mounted instruments.

f) Supply of all types of interconnected cables (signal, control, power cables) between field instrument/ JB’s & layingof cables and cable trays in the skid including cable glands at both ends, angle tray, accessories required for cable

laying & JB’s (as required) is in bidder’s scope.

g) Installation arrangement as shown in the schematic drawing shall be used for guidance. Actual arrangement should

be proposed by vendor and shall be reviewed / approved by GAIL.

h) Power source (for Flow computer and Modem):

Each flow computer shall be powered through two different power sources viz. primary re-chargeable battery and

backup lithium battery for un-interrupted operation of flow computer.The 1st (primary) source of power shall be (user selectable) either 230 VAC to 12/14 VDC or solar power whichshould be capable enough to charge the re-chargeable battery, whereas the 2nd (backup) source of power will be

Lithium battery.

Primary Power source:

A re-chargeable battery ( voltage rating :12V, of minimum 50AH rating Battery) shall be provide power to FC for atleast 720 Hours (30 days) of no sun day operation including data polling for a minimum of 5 times a day using GSMand/or every 15 minutes using GPRS.

There shall be provision for charging the offered re-chargeable battery using appropriate charge regulator using :

a) an external 230 VAC to 12/14 VDC power convertor b) Solar panel in such a manner that battery is charged through solar power when sunlight is available else it will

be charged using the external supply (230 VAC to 12/14 VDC converter). The 230 VAC to DC convertor is to be mounted in a NEMA-4 enclosure in safe area where as the re-chargeable battery shall be mounted in an Ex-

proof Junction box in hazardous area

Secondary Power source :

In addition, flow computer should also have in-built back up lithium battery which it to be used in case of non-availability of primary power. The Lithium battery system should be designed to power on the flow computer for a

min. of 7 days. As soon as re-chargeable battery (primary source) is charged, flow computer will get power thoughthe same (primary source) and the Lithium power source shall be cutoff/ go to stand-by mode (Lithium Batteryrequired to power on, only in absence of power through external battery / when external battery gets discharged).

Re-chargeable Battery, SOLAR power charging system shall be designed for 30 NO sun day operation of FlowComputer including data polling through Modem as mentioned elsewhere. Minimum capacity of re-chargeable

battery shall be 50 Amp-hour, 12 V.

External power source i.e. power convertor (230 VAC to 12/14 VDC) shall be installed in a NEMA-4

enclosure/box at distance of 20 meters from skid and same shall be suitable to charge re-chargeable batterymentioned above. Charging cable of appropriate length shall also be supplied by the bidder.

SOLAR PANEL shall be of minimum 50W along with suitable rating rechargeable battery mentioned above.

Certification shall be provided for use of Solar panel in the Class-I, Div-II, Group C&D.


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Charge Regulator should accept power to charge the re-chargeable battery from either througha) 230 VAC to 12/14 VDC convertor or b) Solar panel.

Input and Output required for Flow computers :

For SOR Item- 4 & 7 :

Minimum I/O required is mentioned below.

Pulse input for LF and HF

RTD Pt 100 (4 wire)

Integral pressure sensor or Analog input for metering PT

For SOR 5 & 8 :

Minimum required is as follows

Pulse input for LF and HF

RTD Pt 100 (4 wire)

Integral pressure sensor or Analog input for metering PT

4 Digital Inputs

2 Digital Outputs

2 Analog Inputs (skid inlet pressure and temperature)

1 PID/ Analog Output (for flow control valve)

In addition to above, provision must be there in the flow computers offered in all SOR items to increase the I/O’s withadd on cards.

2.3 SCOPE OF WORK & SUPPLY:

a) Supply of complete skid package-DRS skids (comprising of filtration and pressure reduction with valves, pipe andfittings) and MRS skids consisting of (Filtration, pressure reduction and Turbine Meter / RPD Meter along with Fieldmounted Flow Computer / EVC) as per SOR, typical P&ID / Schematic line diagram and other technical specifications.

The schematic line diagram/ typical P&ID provided along with the bid document shall also be used to understand the

scope of supply/ work.

b) Vendor scope includes Design, Engineering, Manufacturing, Inspection, Testing, Transportation, Supervision forInstallation & commissioning of complete work of custody transfer skids consisting of two Independent streams ofFiltration, Pressure reduction, flow measurement, Stream Flow computers, safety valves, Pressure Instruments,Temperature Instruments, complete integrated field instruments, piping, fittings and valves in a skid with the following

items described below as a minimum and as shown in the typical P&ID/ line diagram.

c) Metering Skid shall consist of complete metering package (consisting of Filtration, PRS and Turbine flow meter/ RPDMeter for flow measurement) with two independent and redundant streams (1 operating + 1 stand by stream) should bedesigned for 100% of maximum flow capacity indicated above (each PRS/ Metering stream should be designed for 100%

of design capacity of skid). Each of the Gas filtration, PRS and Metering Section shall be of required design flowcapacity meeting the specified operating design conditions as per process data of respective skids. The Vendor’s scope ofwork shall include supply of the complete Gas Filtration, PRS & Metering System in accordance with this specificationand any other codes, standards and regulations stated herein. In each skid, one complete stream will be kept in hot

standby mode (including filtration, Pressure reduction, Metering etc).

DRS shall consist of complete package (consisting of Filtration and Pressure reduction) with two independent andredundant streams (1 operating + 1 stand by stream) should be designed for 100% of maximum flow capacity indicated

above (each Pressure reduction stream should be designed for 100% of design capacity of skid). Each of the Gasfiltration, PRS section shall be of required as per design flow capacity meeting the specified operating design conditionsas per process data of respective skids. The Vendor’s scope of work shall include supply of the complete Gas Filtration,PRS System in accordance with this specification and any other codes, standards and regulations stated herein. In each

skid, one complete stream will be kept in hot standby mode (including filtration, Pressure reduction etc). Maximum permitted velocity through main header/ pipe / nozzle of filtration, pressure reduction, Metering shall be limited to 20meter/sec.

d) The scope of supply for DRS (SOR Items- 1 & 2) as a minimum shall include, but not limited to the following.

i) One gas filtration system with two dry gas Horizontal/ Vertical type filters (1 operating + 1 standby stream), eachdesigned for 150 % of rated flow capacity of skid(s). The dry gas filtration system shall be used to remove dust particlesless than 3 micron with 99% efficiency and to remove condensate if any. Fire case Pressure safety Valves (PSV,


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designed for fire case) shall also be provided on each filter. Filter cover shall have arrangement of Davit arm for ease ofmaintenance.

ii) Pressure Reduction system with 2 streams of pilot operated Slam shut valve and Pressure Regulators (1 operating + 1standby stream). Each stream shall contain two regulators (Active and monitor), it means, if active regulator fails then theother one (monitor) will maintain desired output parameters. Under normal conditions, the downstream regulator is

considered as active regulator and upstream regulator performs the monitoring function. Active regulator shall be “fail to

open” and monitor regulator shall be “fail to close” type. Vendor shall confirm that the noise level for the PCV (Active &Monitor) is within 85 dBA. In case, noise level through PCV is ≥ 85 dBA, Vendor shall provide noise treatment to limit

the noise level and include silencers or expanders as required in the scope of supply. Set Point of the PCV Pilots andSlam Shut Valves shall be adjustable. Vendor shall furnish the adjustable range of the offered pilots and slam shut

valves. The construction of the Pressure Regulator shall be such that there will be no continuous gas bleeding.

e) The scope of supply for MRS ( SOR Items- 3 to 8) as a minimum shall include, but not limited to the following.

i) Gas filtration system consisting of two(2) stream of dry gas Vertical type filters (1 operating + 1 standby stream), eachdesigned for 150 % of rated flow capacity of skid(s). Dry gas filtration system shall be used to remove dust particles less

than 3 micron and to remove condensate if any. Fire case Pressure safety Valves (PSV) shall also be provided on eachfilter. Filter cover shall have arrangement of Davit arm for ease of maintenance.

ii) Gas metering system consisting of two(2) streams of metering system (1 operating + 1 stand by stream) with Turbine

flow meters/ RPD flow Meter, flow conditioner, meter runs. Field mounted Flow Computer / EVC (as applicable) shall be provided for each meter stream with all interface accessories. Each metering stream shall be designed for 100 % of

capacity. The maximum permitted velocity through flow meter shall be 20 meter per sec. The Gas Flow Meter shall becertified for custody transfer application by a certifying agency equivalent to Nmi/ PTB/ NPL. For Turbine based skids(SOR- 5 & 8), Meter run (10 D upstream and 5 D downstream) and Flow straightener is envisaged. The Flow metersshall be air calibrated.

iii) Pressure Reduction system consisting of two(2) streams of pilot operated Slam shut valve and Pressure Regulators (1

operating + 1 standby stream) shall be designed. Each stream to contain two regulators (Active, monitor), it means, if oneregulator fails the other one will maintain desired output parameters. Under normal conditions, the downstream regulatoris considered as active regulator and upstream regulator performs the monitoring function. Active regulator shall be “fail

to open” and monitor regulator shall be “fail to close” type. Vendor shall confirm that the noise level for PCV / Regulator

(Active & Monitor) is within 85 dBA. In case, noise level is ≥ 85 dBA, Vendor shall provide noise treatment to limit the

noise level and include silencers or expanders as required in the scope of supply. Set Point of the PCV Pilots and Slam

Shut Valves shall be adjustable. Vendor shall furnish the adjustable range of the offered pilots and slam shut valves. The

design/construction of the Pressure Regulator shall be such that there will be no continuous gas bleeding.

f) Skid mounted field instruments like Pressure & Diff. Pressure gauges, Temperature gauges, Pressure Transmitters,Temperature elements & Thermo wells, limit switches for slam shut valves shall be supplied along-with the skid.

g) The metering stream (flow meter, flow straightener impulse tubing of Pressure transmitter, thermo-well) shall becompletely insulated to ensure an even heat transfer throughout the meter run when subjected to ambient environment.

h) The custody transfer equipment at field like transmitters (pressure & temperature) shall be installed in an environmentalenclosure to minimize the effects of ambient temperature variations and shall be lockable for prevention of unauthorized

data entry.

i) On line Battery operated field mounted Flow Computer is required for all SOR Items 4, 5, 7 and 8. SOR Items 3 & 6,shall be supplied with Electronic Volume corrector (EVC shall be inbuilt with RPD or field mounted EVC).

The system shall be designed in such a way that it should operate through battery. Bidder shall submit the Battery sizingcalculation, details of battery (make, model, rating), Product Technical Literature along with offer. The Rating, make and

other necessary details in support of selected model for Battery shall also be submitted along with offer. The powerconsumption of Flow Computer, Modem, PT (low power consumption) and other associated utilities of online systemshall be considered for Backup calculation and finalisation of sizing of Battery.

j) Internal / external USB converter shall also be provided with each Flow Computer and EVC for assessing/ connectingfor configuration through Laptop PC through the USB port of the respective FC/ EVC.

k) Supply and installation of all tubing, instrument fittings, pipes, pipe fittings, other fittings, valves, gaskets, bolts, nuts,

spades, etc, within the skid and its battery limit are in bidder’s scope.

l) Supply and installation of all required cables (including earthing cable), cable trays, earthing strips for grounding/earthing of skid and wiring within the skid. All Interconnecting cables between Skid, Instrument / Junction boxes. Bidder

to supply required mounting accessories for Cabling, glanding, tray work etc.


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m) Supply and installation of Junction boxes (as per the requirement of hazardous area classification) for power, signal,alarm, instrument and control cables with suitable cable glands (if applicable) are in bidder’s scope.

n) Structural skid complete with necessary drip pan, walkways, staircase, platforms, crossover, gratings, handrails for accessfor operation and maintenance are in bidder’s scope. Details of skid assembly, supporting positions, Anchor bolt layoutand equipment weights to be provided prior to equipment supply.

o) Lifting lugs and spreader beam / frame, foundation Anchor bolts, copper jumpers for flanges for the skid, Stainless steelnameplate for each tagged equipment and component; All Tie-ins with flanged connections shall be in bidder’s scope.Earth bonding system and earthing boss for skid are in bidder’s scope. Inlet and Outlet matching flanges and Studs &nuts (for skid interconnection and Inlet & Outlet piping connection), suitable Gaskets shall also be supplied along-with

each skid.

p) Software :

i) Vendor to provide licensed Software in the name of GAIL for authenticating the algorithm written in the Flow

Computer/ EVC as per AGA.

ii) Vendor to provide the necessary hardware/ software (licensed in favour of GAIL) for configuration of FlowComputer / EVC. Vendor shall provide all the details and required soft-ware for SCADA communication.

iii) Vendor to supply all the hardware / software (licensed in name of GAIL) for accessing data of Flow meter/ flowcomputer.

q) The Vendor’s scope of work shall also include:

i) Inspection and testing of all components, sub-assemblies, and complete assemblies of items manufactured atVendor’s works, and other sub-vendor’s works in accordance with approved QA/QC procedure.

ii) Shop assembly and hydro-test and Factory Acceptance Test (FAT) for the complete package at Vendor’s worksas per approved FAT procedure.

iii) Supervision of Installation, start-up and commissioning of the complete package at site. Site acceptance test(SAT) for the complete skid as per approved SAT procedure.

iv) Preparation for shipment, packing and delivery of all packages, equipment and material to site.

v) Installation assistance, Start-up and commissioning assistance at site.vi) Preparation and submission of all documents including final as built drawings, technical documents as per

purchase requisition along with the bid and after award of contract. Preparation and submission of Finaltechnical Documentation, test / calibration reports, certificates, Completion files as per this specification. Two

copy (hard copy and soft copy) shall be submitted along with the complete system at stores / site for each skid.

r) RPD flow meters shall have turn down ratio of 1:40 (minimum) and accuracy shall be within 1% of readings for flowrange from 20% to 100% of Qmax. 5 point Air calibration is required for RPD flow meters.

2.3.1 Any work not specifically mentioned but otherwise required, as per statutory rules/ codes and standards/ specifications and/

or for the completion and operation of equipment to the entire satisfaction of GAIL have to be done by the VENDORwithout any commercial implications.

2.3.2 The scope of work also includes the mechanical and structural detailed design of the skid, procurement of materials,

preparation of fabrication drawings, detailing of internals, fabrication, inspection and testing of the piping and structuralitems at fabrication shop, painting, internal coating if any, preservation, transportation and undertaking Guarantee for the

equipment.

2.3.3 The scope of supply of skid also includes supply of mandatory spares as per list provided elsewhere.

2.3.4 The VENDOR shall assume single point responsibility for all aspects of job. This shall include timely completion, liaisonwith CONTRACTOR, liaison with VENDOR of specified items, co-ordination of the work, quality and guarantee

for the equipment.

2.3.5 Where parts of the package are subcontracted and purchased by the VENDOR, these become part of the Vendor’s package

and it is the Vendor’s responsibility to ensure that the complete package complies with the specifications, codes andstandards and statutory regulations.

2.3.6 Scope of supply/ installation includes all instruments shown in the P&ID/ schematic, as within the Vendor’s scope.

2.3.7 The Vendor shall be responsible for obtaining necessary approvals, authorization and certification from local Government /


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Local Statutory bodies, Authorized Inspector and Third Party Inspection Agency as applicable.

2.3.8 The equipment shall be suitable for the site conditions specified. All components/ consumables used shall be new and of

current manufacture.

2.3.9 In the event of any conflict between this specifications, data sheets, related standards codes etc., vendor shall refer the matter

to the PURCHASER for clarifications and only after obtaining the clarification shall proceed with the manufacture of the

items in question.

2.3.10 Vendor shall take single point responsibility for the engineering, design, certification, procurement, inspection, testing,supply & performance of the Gas Pressure Reducing and custody transfer metering skids along with all instruments,

equipment and valves offered/ supplied in the skids based on the data sheets and the specifications furnished, taking into

consideration successful operation, safety and established International standards for the complete skids. As a part of skiddesign & engineering, the following shall be undertaken/ decided/ furnished by bidder:

a) Calibration of flow Meters (using air at/ near atmospheric pressure) considering the above mentioned overallaccuracy/uncertainty. RPD meter shall be air calibrated at 5 points. RPD Meter shall be calibrated at 0.05 Qmax,

0.2 Qmax, 0.4 Qmax, 0.7 Qmax, and Qmax. (i.e at flow rates of 5%, 20%, 40%, 70% and 100% of Qmax), subjectto minimum flow rate of 5 M3/Hr (or minimum flow rate as per calibration agency/ Laboratory).

b) The calibration of Turbine meter shall be performed at 7 different flow points. Calibration of Turbine Flow Meters

shall be done at the following nominal flow rates: 0.025 Qmax, 0.05 Qmax, 0.1 Qmax, 0.25 Qmax, 0.5 Qmax, 0.75Qmax, and Qmax. as per AGA- 7. (i.e at flow rates of 2.5%, 5%, 10%, 25%, 50%, 75% and 100% of Qmax),

subject to minimum flow rate of 5 M3/Hr (or minimum flow rate as per calibration agency/ Laboratory).

c) Based on the approved design and tender requirement, Sizing of pipes, filtration, flow meters, self-actuatedPressure control valves, Safety Shut Off (Slam Shut) valves, Pressure relief valves, Creep relief valve.

d) Set points for Pressure Regulators (active, monitor) and slam shut valves.

e) Instrument ranges to meet the Process operating and design conditions.

f) Noise calculations for Regulators. Vendor to provide detailed Noise calculation and standard used and assumptionconsidered (if any).

g) All the instruments/ equipment to be procured as per the approved vendor list provided in bid document.

2.3.11 Typical instrument data sheets for Pilot operated control valves (PCVs), Slam shut valves, pressure relief valves, fieldtransmitters, pressure gauges, and accessories indicate materials for body, internals etc. However, this does not absolve theVendor of the responsibility for proper selection with respect to the fluid and its operating and design conditions. Proper

sizing and selection of the pipe, isolation valves, self-actuated pressure control valves for monitor and active regulator, slam

shut valves, pressure relief valves and accessories are vendor’s responsibility.

2.3.12 All the major items like valves (Plug & Ball), Pressure control valves, Slam shut valves, Flow computers, Pressure relief

valves, Pressure & diff. Pressure transmitters, Temperature instruments etc. shall be supplied from the vendor list attachedelsewhere and the offered model of equipment shall have proven track record of successful operation for at least 6 months till

bid submission date (certificate, performance report to be provided as proof).

2.3.13 Vendor shall be fully responsible for proper integration of their supplied systems with GAIL’s SCADA (RTU) systems andshall provide all the technical details to GAIL for configuration at SCADA/ RTU end. Configuration in the supplied Flow

Computer / EVC shall be bidder’s responsibility.

2.3.14 Apart from the above, Bidder shall follow the design and specification listed below.

a. The size of line pipe, inlet/outlet valve size, mentioned in tender is the minimum size of line pipe / port/ nozzle size of eachcomponent of Skid package. Components should be selected and designed for maximum designed gas flow rate at the

minimum pressure (inlet/ outlet as the case may be). All pressure parts shall be designed for design pressure and temperaturementioned elsewhere. Unless specified & clarified by GAIL, sizes indicated in P&ID shall be followed for all pipe, mainline

valves and nozzle size. Materials, Equipment, items, components selected for skid should be suitable for natural gas applicationand shall not erode during operation at worst process condition. All pipe work and equipment must be capable of withstandingthe maximum pressure resulting from a fault condition.

b. Gas velocity in main line pipe, equipment, flow meter, main line valves, check valve etc must not exceed 20 meters/second,(except SSV and PCV), when the maximum flow rate occurs at the lowest expected inlet pressure. Velocity limit for SSV shall

be 40 m/s.


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c. Regulators/ SSV of minimum 1” size is required in this project. Regulator and SSV of lower than 1” size shall not be accepted. Noise through Regulator (Active/ monitor) shall be limited to 85 dB. The allowable pressure drop and noise values in regulatorshould not exceed permissible limits.

d. Complete DRS (SOR Items 1 and 2) shall be designed for 49 Kg/cm2g. Whereas MRS envisaged in SOR Items- 3 to 5, shall bedesigned for 49 Kg/cm2g up to downstream header of Pressure Reduction (Inlet, Filtration and Pressure reduction system,

including downstream valves of pressure reduction system) and the downstream of pressure regulation (after downstream ball

valves) shall be designed for 19 Kg/cm2g. Safety Valve (provided on Filter of these MRS skids) shall be set at design pressure,i.e. 49 Kg/cm2g.

For SOR Items- 6 to 8: Complete skid shall be designed for 19 Kg/cm2g pressure. All pipe, fitting and equipment (except

RPD Meter) must be capable of withstanding the maximum pressure resulting from a fault condition. RPD meter shall be

designed for 12 Kg/cm2g pressure. Safety Valve (provided on Filter) shall be set at design pressure, i.e. 19 Kg/cm2g. DesignTemperature for MRS and DRS shall be -29 deg. C to +65 Deg.C.

Charpy Test for all PRS downstream components (including Regulators, valves etc) shall be done at 0 (zero) degree C.

e. In MRS, Metering shall be done though Turbine meter (for SOR- 5 & 8) / RPD Meter (for SOR- 3, 4, 6 & 7). For SOR Items-4, 5, 7 and 8, Solar powered Flow computer with integral pressure sensor (for metering pressure sensing with pressure range of

gauge pressure sensor shall be 0-8 Kg/cm2g) is envisaged. However for SOR Items-3 & 6, Electronic volume corrector with battery pack is acceptable.

Turbine flow meter and RPD flow meter shall be designed for 19 Kg/cm2g and 12 Kg/cm2g pressure respectively.

f. Flow computer with In-built MVS sensor (for metering pressure) is acceptable. Alternately, separate/ independent meteringPressure transmitter is also acceptable.

g. The DRS and MRS should have provision for stream selection. Automatic switch over from active stream to hot stand-bystream should take place in the event of shut down/ trip of the active stream for any abnormal reason.

In DRS, apart from skid inlet & outlet ball valves, there shall be one inlet and one outlet valve (of 300#) on every stream offiltration with pressure reduction. PRS downstream header shall be designed for 150# and a flanged connection shall be

provided at PRS downstream header. Suitable transition piece (from vendor list) suitable for connecting to MDPE pipes,PE100 shall be provided. Each of the valves shall be designed to seal on both upstream and downstream faces and the space between the faces shall be fitted with vents.

h. Pressure test points, pressure gauges, purge and vents shall be provided as specified in the schematic line diagram/ drawing/typical line diagram/ schematic provided in tender. All the ends of drain shall be blinded/ plugged. The drain and purge valves provided at the inlet and outlet ends shall be fitted at sufficient gap from the base level of the skid, so as to facilitate an easyoperation of the same. Vent valves shall be provided at sufficient height to facilitate venting (at 3 meters height from platform/

base).

i. Schematic line diagram/ P&ID of DRS and MRS provided in tender shall be used for guidance purpose. Before fabrication,actual arrangement (GAD) shall be proposed in soft & hard form by the vendor, for review and approval by GAIL. No

procurement/ fabrication job shall be undertaken/ started without written approval of GAIL.

j. Vendor list provided in tender for bought out items, shall be followed for procurement for bought out items required in DRS/MRS. The acceptance of make/ model of instrument, equipment, component offered by the bidder shall be at the sole discretion

of GAIL.

k. The data sheet (provided with tender) should be filled up completely, signed, stamped and enclosed along with sizingcalculation, catalogue and drawings in the Technical Bid submitted by the bidder. Technical literature in English language,

along with dimensional details of the equipment and system hook up drawing shall be submitted by bidder along with thetechnical bid.

l. In general, all the connections in the DRS having design rating of 300# should be of welded or flanged type (threaded joints/connections are not allowed) only. Only flanged and welded connection shall be used in DRS/ MRS. Unless clarified/ specified by GAIL, no threaded connection shall be used in DRS/ MRS. Only blind plugs for drain connection can have threaded

connection in DRS and MRS.

m. Hole tight / leak tight shall not be used on threaded / flange joints. For all flange joints, Stud with nuts (hot dip galvanized)shall be provided on flange joints. All Studs and nut used in this project shall be hot dip galvanized as per ASTM A 153 orequivalent.

n. No Flange made of cast iron, ductile iron or non-ferrous materials (brass or bronze) shall be used in skid. Flanged connections(in mainline, inlet and outlet) of the DRS and MRS should be in sizes of 1”, 1.5”, 2”, 3”, 4” and 6” only (as defined in line


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diagram). All instrument fitting/ tubing etc shall be of SS316 (minimum). No tube fitting/ tube of brass/ copper shall be used. No valve Components like Valve body, bonnet, cover and / or end flanges made of cast iron or ductile iron shall be used.

o. Suitable transition fittings (required for connecting to MDPE pipes) shall be provided at DRS outlet end. Suitable transitionfittings (required for connecting to MDPE pipes) shall be provided at inlet and outlet of MRS.

p. The MRS shall have twin independent streams of Filtration, pressure regulation and Turbine meter/ RPD metering system

(along with solar powered flow computers). Solar panel, battery, flow computer etc shall be installed with required mountingarrangement and accessories as per best engineering practices. GPRS enabled GSM Modem shall also be provided in Flowcomputers. For metering temperature a RTD sensor shall be installed at Meter downstream and shall be connected for flowcomputer.

q. DRS and MRS shall be skid mounted on base frame of required size/ dimension. Suitable cabinet is required for DRS and MRS(entire skid shall be provided in cabinet). Cabinet shall be made out of frame comprising of angle of minimum 75 mm widthand 5 mm thickness (minimum) and covered with MS sheet/ plate of 2.6 mm thickness from all sides and top. Suitable stiffener

shall be provided as per requirement. Checkered plate of appropriate strength shall be provided at bottom of skid cabinet.Suitable mounting arrangement/ anchoring shall be provided in skid base frame. The cabinet shall be suitable for outdoor

installation. Top shall be slanted to avoid water inrush during rain. One side (front side) of cabinet shall be lockable fromoutside, whereas the other sides (rear, top, side etc) of cabinet shall be lockable from inside the cabinet (GAD to be got

approved before proceeding for fabrication).

r. DRS & MRS shall have pressure gauges provided at skid Inlet & skid outlet, mounted suitably in the cabinet of DRS / MRS, soas to view it from outside of cabinet (without opening the cabinet). A cut out of suitable dimension shall be provided in cabinetof DRS/ MRS for viewing reading of Pressure gauge and flow computers. Suitable glass cover (with locking arrangement) shall

be provided in cabinet to read/view the flow computer.

s. Vendor shall supply the flow computer with IS Junction Box installed on the suitable Mounting frame/arrangement as perGAIL site requirement. It shall have the stainless steel tubing connected to the pressure inputs using suitable SS tube fit ting and

the other end of the tubing will be terminated in 2-Way Manifold Valve.

t. The pressure gauges shall be aligned with reference to the regulator, such that it facilitates an easy viewing of the readings inthe pressure gauges. Arrangement for venting of pressure gauge and also pressure sensing lines shall be provided in skid. For

DRS/ MRS, the DP gauge shall be supplied along with 3-way, 5-valve manifold, whereas 2-way manifold is required for PGs.

DRS and MRS design shall meet various requirements of national/ international standards such as ANSI B-31.3/31.8; ASME

Sec. VIII, Div-I; EN-12279; EN-12186; IGE-TD-13; AGA-5, AGA-7 & AGA-8 and PED 97/23/EC Compliance.

Vendor shall design the DRS and MRS suitable for outdoor installation in tropical climate with the following conditions: Ambient temperature: 0 to +60°C. Humidity: 100%. Design Temperature shall be -29 to +65°C.

u. DRS shall have twin stream dry gas filters & Pressure reduction (with hot stand-by) in Active-Monitor configuration. Nometering is required in DRS. Whereas, MRS shall have twin stream of dry gas filters, twin-stream Pressure reduction (with

hot stand-by) in Active-Monitor configuration and twin-stream turbine flow metering/ RPD Metering system.

Skids shall have Lifting lugs/ Hooks of adequate strength provided to facilitate its lifting and convenience in handling.

v. Working platforms, if required should be provided in the skids at appropriate locations (and shown clearly in the drawing) tofacilitate easy access to all parts of the skid and to avoid any operational or maintenance problems.

w. Pressure test points, purge and vent points shall be fitted as indicated in the Installation Schematic drawing attached

herewith. When a test point is not provided on an item of equipment, a point shall be provided on the adjacent pipe work. Allthe ends of drain and vent points shall be plugged. The vent purge valves provided at the inlet and outlet ends shall not befitted very close to the base level of the skid, which will be very difficult to be operated. A common vent header with flamearrestor along with flapper shall be provided.

x. The bidder shall use only SS Pressure tubes ½” OD (SS316) or 3/8” OD(SS316) (of make: - Sandvik), SS tube fittings (of

make: Parker/ Swage lock / HYLOK). No other make is acceptable.

y. Bidder shall take care of requirement of Pressure Tubing’ & its associated job for connection from the ½ Inch tap off

provided from the Pipe to the 2-way valve manifold for Inlet Pressure connection (single stream) & outlet pressureconnection (twin stream).

Suitable provision shall be provided by bidder to avoid entrainment of liquids in the gas entering regulator assembly. If

required, means for removal should be provided by bidder. Sizing of components should be done considering avoidance ofunacceptably low temperatures, which may lead to requirement of preheating.


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Skid should have a provision for stream selection wherever specified / mentioned in the specific requirements. Automaticswitch over from active stream to the hot standby stream should take place in the event of shut down of the active stream for

any abnormal reason.

In MRS, there shall be separate inlet and outlet valve in each stream of Metering section. Each valve shall be designed to seal

on both upstream and downstream faces and the space between the faces shall be fitted with vents.

Turbine/ RPD flow meter (of MRS) shall be positioned in such a way that the index can be read conveniently. Suitablemeans to avoid condensation of water inside index head shall be provided by the bidder. When reading/ viewing the indexhead, the gas flow direction through the meter shall be from the left to the right.

Technical literature (in English language only), dimensional details of the equipment and system hook up drawing shall besubmitted along with the technical bid. The data sheet should be filled up completely and should be enclosed along with theTechnical Bid.

Compliance with Technical Specification will be taken for granted by GAIL, if deviations are not specifically mentioned and

accepted by GAIL. Any deviation from the specified technical specification, vendor list, datasheet etc should be highlighted by vendor. However, the acceptance of the same shall be at the sole discretion of GAIL.

As far as possible, all joints shall be Flanged joint only. No threaded joint shall be proposed / considered by the bidder. Stud

nuts are to be provided on flange joints. Hole tight / leak tight should not be used on threaded / flange joints in skid.

Flanges, fitting or any other skid component made of cast iron/ ductile iron/ non-ferrous materials (brass or bronze) is not

acceptable. Cast iron, ductile iron, non-ferrous materials (brass or bronze) shall not be used in skid/ skid components. All theflanges used in skid shall be raised face. Flanged end connections for station piping (inlet and outlet) of the DRS/MRSshould be in sizes of 4” and 6” only. Bidder to provide suitable transition fittings on flanged ends and to ensure compatibilitywith MDPE pipes. All stud bolts and nuts used in CGD networks shall be hot dipped galvanized as per ASTM A 153 or

equivalent.

Vendor shall confirm that the Skid is suitable for outdoor installation in tropical climate with the conditions specified intender. All required cable, conduit and suitable cable gland (ex-proof) required for power, signal, pulse input, RTD shall be

supplied / installed by bidder. The Supply & laying of perforated cable tray on supports and accessories required for cablelaying and routing lies in the scope of the bidder. All interconnecting signal, power, control cables used in the skid shall bearmoured. The signal/control cables shall be individual pair shielded and overall shielded. Vendor shall follow the cable

specifications as per control cable standard specifications. Battery shall be installed in ex-proof JB/ enclosure. Certificates

for JBs, enclosure shall be provided by bidder.

Bidder shall carry out installation of junction boxes on separate support, JB earthing / grounding, tagging, ferruling, cableglanding & termination, pair/ core identification of all cables.

The Supply & laying of earthing strip and earthing cables (copper) for earthing of instruments, junction boxes etc. toinstrument earthing system lies in bidder’s scope. Bidder shall supply required earthing strip/ cable for earthing.(Earth pit shall be provided by GAIL. However Hardware required for interconnection shall be provided by bidder).

Provision for anchoring skid (on foundation) shall be provided by bidder. Supply of suitable anchor bolts (preferably of 16

mm size) also lies in bidder’s scope.

Tapping with valve required for PG connection shall be of 3/4". PG shall have 1/2" NPT(M) as process connection.

Spring range of offered PCV/ Regulator in MRS (SOR-3 to 8) shall be 1 to 5 Kg/cm2g. SSV and CRV shall be designedaccordingly. For sizing of skid- PRS downstream components/ skid items/ equipment like Meter, Valves, Pipe etc, delivery

pressure (outlet pressure) shall be considered.

The following performance characteristic curves should be furnished:

a) Outlet pressure v/s flow (for various inlet pressures) b) Inlet pressure v/s flow (for various outlet pressures)

3.0 DESIGN PHILOSOPHY

3.1 GENERAL

3.1.1 This Document together with the attachments covers the minimum requirements for the design and engineering of skid

complete with all accessories. Bidder shall be responsible for Design, engineering, sizing, selection, manufacture and/ or

procurement, of materials, components and equipment necessary for complete package.


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3.1.2 This document provides in detail, the minimum qualitative requirements of most of the instruments. For instruments, whereno such requirements are indicated in this document, the bidder shall submit the same for GAIL,s approval. For meteringsystem, vendor shall submit the complete design and engineering of the skid including piping duly approved by NMI/ PTB/

NPL or Meter manufacturer for custody transfer application.

3.2 CODES AND STANDARDS

3.2.1 Design and terminology shall comply, as a minimum, with the latest edition prior to the date of bid enquiry of followingcodes, standard practices and publications:

AGA American Gas Association, Gas Measurement Committee

Report No.3 – Orifice Metering of Natural Gas.

Report No.7 - Measurement of Gas by Turbine flow Meter / RPD Meters.ANSI / ASME American National Standards Institute/ American Society of Mechanical Engineers.B 1.20.1 Pipe Threads.

B 16.47 Steel Pipe Flanges and Flanged Fittings.B 16.20 Ring Joint Gaskets and Grooves for Steel Pipe Flanges.

ANSI/FCI American National Standards Institute/Fluid Controls Institute70.2 Control valve seat leakage classification.

API American Petroleum InstituteRP 520 Sizing, selection and installation of pressure relieving system in refineries.

Part-I - Sizing and selectionPart-II - Installation

RP 521 Guide for pressure relieving and depressurizing systems

P 526 Flanged steel safety relief valves.RP 527 Seat tightness of pressure relief valves.MPMS Manual of Petroleum Measurement Standards.RP 551 Process Measurement Instrumentation.

Part 1 - Process Control and Instrumentation

RP 552 Transmission SystemsS 1101 Measurement of Petroleum liquid hydrocarbon by Positive Displacement meter.S 2000 Venting Atmospheric and low pressure storage tank.

S 2534 Measurement of liquid hydrocarbons by Turbine Meter / RPD Meter systems.S 670 Vibration, Axial-Position and Bearing-Temperature Monitoring Systems.ASTM American Society for Tests and Materials.

BS British StandardsBS-1042 Measurement of fluid flow in closed conduits.BS-4368 Compression coupling for tubes.BS-4800 Colours for ready mixed paint.

BS-5308 Part-2 Specification for PVC insulated cables.

BS-6364 Specification for valves for cryogenic service.BS-7244 Flame Arrestors for general useDIN-43760 Temperature v/s Resistance curves for RTDs.

DIN-19234 Electrical Distance Sensors; DC interface for Distance Sensor and Signal Convertor.IBR Indian Boiler Regulations.

IEC International Electro-technical Commission.

IEC 60079 Electrical Apparatus for Explosive Gas atmosphereIEC 60085 Thermal Evaluation and Classification of Electrical Insulation

IEC 60332 Test on bunched wires or cables. Part 3 Cat 1IEC 60331 Fire resistance characteristics of electrical cables

IEC 60529 Classification of degree of protection provided by enclosures.IEC 60534-2 Industrial Process Control Valves-Flow capacityIEC 60584-2 Thermocouples - TolerancesIEC 60584-3 Thermocouples extension and compensating cables, tolerances and Identification system.

IEC 60751 Industrial platinum resistance thermometer sensors

IS Indian StandardIS-5 Colours for ready mixed paints.IS-319 Specification for free cutting Brass bars, rods and sections

IS-1239 Mild steel tubes, tubular and other wrought steel fittings.IS-1271 Specification of Thermal Evaluation and Classification of Electrical Insulation.IS-1554-part I PVC insulated (heavy duty) electric cables-working voltage up to and including 1100 V.

IS-2074 Ready mixed paints, air drying, red oxide- zinc chrome.

IS-13947 Degree of Protection provided by enclosures for low voltage switch gear and control gear.IS-2148 Flame proof enclosures for electrical apparatus.


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IS-3624 Specification for pressure and vacuum gaugesIS-5831 PVC insulation and sheath of electric cables.IS-7358 Specifications for Thermocouples

ISA Instrument Society of America.S-5.2 Binary logic diagrams for process operations.S-7.3 Quality standard for instrument air.

S-75.01 Flow equations for sizing control valves.

ISO 5167 Measurement of fluid flow by means of orifice plates, nozzles and venturi tubes. NEC National Electric Code. NFPA National Fire Protection Association. NFPA-496 Purged and pressurised enclosures for electrical equipment.

EN European Standard

EN334 European standard for pressure regulators upto 100 barEN12186 Gas Pressure Regulating Stations for Transmission and distributionEN14382 Safety systems for Gas distribution

3.2.2 In general, Bidder shall carryout engineering as per IEC/ BIS standards.

Any other standard, if necessary, can also be referred by bidder during the execution of the job, without diluting the basicrequirements, however with prior information to Owner/ Owner’s Representative. In any case bidder must furnish a list of

codes and standards other than those specified in this document, which shall be followed by them during engineering.

3.3. INSTRUMENT DESIGN CRITERIA

3.3.1 Instrument air shall not be provided by GAIL for FCV operation. Special care shall be paid for dealing the problem arisingfrom possible condensation due to pressure reduction. A well proven system shall be used for this application. Filterregulators, Actuators, pneumatic positioner, I/P converter etc shall be suitable for Natural gas (sour) application.

3.3.2 The Equipment and instrumentation selected for the skids shall be rugged in design and must be well proven in thehydrocarbon industry. Prototype design or equipment of experimental nature or design undergoing testing etc. shall not be

selected and supplied. Following criteria must be applied before selecting a particular instrument item: “The instruments as

being offered/ supplied should have been operating satisfactorily in hydrocarbon industry like Refinery, Petrochemical andGas Processing Plant under similar process conditions for at least 4000 hrs. from the bid due date”. Certificate of end usershall be provided for the same.

3.3.3 All the mainline ball valves of complete skid package shall be full bore type only.

3.3.4 The complete station shall be designed in such a way that the mean gas velocity remains within 20 Meter per second exceptin Pressure regulating valve / slam shut valve. Velocity in the piping upstream / downstream of Pressure reduction stationshall be within 20 Meter per second. Maximum seat velocity of Slam shut valves is limited to 40 meter / second. The

complete skid shall be designed for 100 % of the maximum flow capacity (except Filtration system, which shall be designedfor 150% of skid capacity).

3.3.5 Instrument Requirements for classified area:

a) All electronic/electrical instruments and equipment shall be suitable for area classification as per IEC codes and shall betested by any recognized authority like BASEEFA, FM, PTB, CMRI etc. and shall be certified by CCOE. All the

configurators shall be certified by CCOE.

b) Certified Intrinsically Safe (IS) equipment as per IEC-60079-11 shall be used, in general, in hazardous area. In caseintrinsically safe equipment is not available, flameproof enclosures as per IEC-60079.01 may be considered.

c) Junction boxes and accessories required for flameproof instruments shall also be certified flameproof.

d) All non-flameproof panels and cabinets installed in classified area shall be purged as per requirements specified in NFPA-496; as a minimum.

e) Other type of protection as specified in IEC-60079 shall not be used.

3.3.6 Statutory Approvals

a) Bidder shall be responsible for obtaining all statutory approvals, as applicable for all instruments, equipment.

b) In addition, equipment/instruments/systems located in the hazardous area shall be certified by the local statutoryauthorities for their use in the area of their installation. In general following certification shall be given:

For all intrinsically safe/ explosion proof/ flameproof equipment/ instruments/ systems or equipment with any othertype of protection allowable as per this package which are manufactured abroad and certified by any statutory authority


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like BASEEFA, FM, UL, PTB, LCIE etc. should also have the approval of Chief Controller of Explosives (CCOE), Nagpur.

For all flame proof equipment manufactured locally (indigenously), the testing shall be carried out by any of theapproved test house like CMRI/ERTL etc. The equipment shall in addition bear the valid approval from ChiefController of Explosives, Nagpur and a valid BIS license.

For all intrinsically safe equipment manufactured locally (indigenously), the testing shall be carried out by any of theapproved test house like CMRI/ERTL etc. The equipment shall in addition bear the valid approval from ChiefController of Explosives, Nagpur.

Custody transfer approval from NMI/ PTB/ NPL or equivalent body from the country of origin.

CCOE certificate for the skid items / components shall be submitted during detailed engineering, however appropriateapproval certificates from the country of origin shall be provided with the bid.

3.3.7 All instruments in the skid shall be certified for IEC Zone 1 Gas Group IIA/IIB, T3.

3.3.8 Instruments, which are not available as per their standard design from any reputed manufacturer as intrinsic safe, can be

supplied in flameproof design. All such instruments shall be certified flameproof for the area classification and requirementsindicated in clause 3.3.6 above.

3.3.9 Flame-proof (explosion proof) junction boxes as applicable shall be certified for IEC-Zone-1, IIA/IIB for all the classified

areas for flame proof instruments.

3.3.10 The sizing for Pipe, Filters, Safety valves, Pilot operated self-actuating pressure control valve, Monitor valve, slam shutvalve, Turbine Meter / RPD Meter.

3.3.11 Any change in instrument size or revision in line sizes because of sizing shall be carried out by bidder without any financial

implications to GAIL.

3.3.12 All field instruments shall be provided with canopies of adequate size and strength to protect instruments from direct rain &

sunlight. All such canopies shall be prefabricated type of FRP material with sufficient strength.

3.3.13 Tube Fittings used for the installation of instruments shall be tested as per BS 4368 or equivalent standards.

3.4 JUNCTION BOXES AND CABLING PHILOSOPHY

3.4.1 Cable Routing

3.4.1.1 Single / multiple pair cables between instrument and junction box shall be through perforated trays. Cable glands shall be

provided at instrument end and junction box end. Supply of interconnected Cables is in bidder’s scope.

3.4.2 Junction Box

3.4.2.1 In general separate junction boxes shall be used for the following (if applicable):

a) 4-20 mA DC signals (IS)

b) Metering Signalc) Contact signals (Field switches, Limit switches, push buttons etc.)

d) Power supply to various instruments ( Flow Meters/ Flow computers/ Transmitters)

Separate JBs and cable are required for power supply to flow Meters and flow computers. The JBs shall have side entry forBranch cable/ single pair cable and Bottom entry for multi-pair cable entry. No top entry shall be considered.

3.4.2.2 The multi-cable entry for 6-pair JB and 12 pair JB shall be 1" NPT (F) and 1.5” NPT (F) respectively. Each junction box

shall be provided with 2 multi-cable entries from the bottom of the junction box with one plugged with weather proof plugs.

3.4.2.3 Junction boxes, cable glands and accessories shall be weather proof in general. Slipper type PVC sleeves shall be used overcable glands for all cable entries in junction boxes to avoid water entry in junction boxes. In case of explosion-proofcomponents used (only for packages), the respective junction boxes, cable glands and accessories shall be certified weather-

proof and explosion proof.

3.4.2.4 Only one multi-cable entry shall be used in the junction box. The other cable entry shall be plugged.

3.4.2.5 The junction boxes in the field as well as in local panel shall be provided with sufficient number of terminals to terminate allthe pairs of multi-cable (including spare pairs) and shields of individual pairs as applicable.


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3.5 INSTRUMENT PAINTING REQUIREMENTS

3.5.1 All instrument impulse lines (except SS 316 Tubing) and instrument structural items shall be painted by the bidder.

3.5.2 The painting/ coating shall be performed in totality for all instrument items such as:

a) All line mounting and equipment mounted instruments. b) All instrument impulse piping (except SS 316 Tubing)c) All instrument structural items like M.S. cable trays, instrument supports and tray supports, instrument stanchion,

impulse line supports etc.

d) All surfaces of GI items wherever repair has been carried out shall also undergo painting.

e) All cabinets/panels, base frames which have undergone repair at site shall also be painted.f) The final coating on external surfaces shall be applied just before handing over the plant or commissioning of the

plant. Name of the manufacturer, colour and quality of all types of primers and paints shall be subject to approval

of the owner/owner’s representative.

3.5.3 Painting of other equipment shall be as per Painting specifications attached elsewhere.

4.0 PROCESS DESCRIPTION

4.1. The bidders shall design the skid considering the worst case process condition scenario.The set pressure of Pilots for PCV (Active & Monitor) & SDV shall cover the complete range of inlet & outlet condition. In

case of PCV / regulator (Active & Monitor) and Slam shut Valve, if one single pilot is not able to cater the complete set

pressure range, then additional suitable pilot / loose springs shall be supplied for each PCV / regulator (Active & Monitor)and Slam shut Valve for each skid.The Filter-PSV shall be set at maximum design pressure. However it shall be designed in such a way that the set pressure can be adjusted within the operating pressure range/ set points. Separate spring(s) shall be provided, if one spring is not sufficient

to meet the requirement.

10 % of the maximum flow capacity shall be considered as the minimum flow.Design Temperature: -29 to 65 deg C.The maximum permissible pressure drop across the complete DRS skid and MRS skid is 3.0 kg/cm2g and 2.0 kg/cm2g

respectively.

4.2. Detailed Process conditions:

Each stream of PRS / Metering in the quoted skid shall be designed for flow capacity of 100% of maximum flow mentionedabove.The Heating value of Natural gas (GCV) shall be 9200 to 9880