technical specification tankage

8/2/2019 Technical Specification Tankage

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TANKAGE TECHNICAL SPECIFICATION

Signature & Seal of Bidder Page 1

TECHNICAL SPECIFICATION

CONTENTSChapter No. Title Page No.

I Special Instructions to Tenderers 2

II Technical Specification 5

01.00 Scope of work 5

02.00 Scope of Supply of Materials 7

03.00 Material Specification 10

04.00 Design and Drawings 11

05.00 Fabrication and Erection 11

06.00 Fabrication and installation of underground tanks 22

07.00 Cathodic protection 24

08.00 Inspection 30

09.00 Testing of Tanks 31

10.00 Calibration of Tanks 33

11.00 Miscellaneous 33

12.00 Welding Requirements 34

13.00 Gauge Pole sleeve 35

14.00 Data to be furnished by successful bidder 35

15.00Technical specification for Civil works 36

Annexure I Specification for Nozzles and Pipes 50

Annexure II List of Standards 51

Annexure III Quality Assurance Plan 53

Annexure IV Painting details 58

Annexure V Drawing Index 65

Annexure VI Tank Data Sheet 66


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I. SPECIAL INSTRUCTIONS TO TENDERERS

01.00 GENERAL

01.01 Hindustan Petroleum Corporation Limited (HPCL) is setting up additional storagetanks at Ajmer, Jaipur and Rewari Terminals These Terminals are currently under

operation. The tender is being floated for construction of additional tanks for HSD & MS

and also Water storage tank.

01.02 The scope of this tender consists of the construction of mild steel tanks required for

storing MS ,HSD & Water as under

Details of tanks to be constructed are shown in the Table below:

FR Floating Roof, CR- Cone Roof, OR-Open Roof

Floating roof shall be of single-deck pontoon type for tanks of dia. more than 12m andup to 60m. Sand pad foundations shall be provided for supporting the vertical storage

tanks.

01.03 The materials, design and workmanship shall satisfy the relevant Standards, the job

specifications contained herein and codes referred to. Where the job specifications

LOCATION Details of tanks to be constructed Design Code

Ajmer 24 M Dia x 14 M Ht- 2 Nos. (FR)-MS

18 M Dia x 12 M Ht- 2 Nos. (FR)- HSD API 650

Jaipur 28 M Dia x 14 M Ht - 1 Nos (FR)- HSD

18 M Dia x 13 M Ht - 2 Nos (FR)-MS API 650

Rewari 17 M Dia x 12 M Ht - 1 No. (FR)-MS

20 M Dia x 14 M Ht - 2 Nos (CR)-HSD

13 M Dia x 14 M Ht 1 No. (OR)-Water

API 650


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stipulate requirements in addition to those contained in the standard codes and

specifications, these additional requirements shall also be satisfied. In the absence of any

standard / specification / codes of practice for detailed specifications covering any part

of the work covered in this tender document, the instruction / directions of Engineer-in-charge will be binding on the contractor.

01.04 Wherever it is stated in this Tender document that a particular supply is to be effected or

that a particular work is to be carried out, it shall be understood that the same shall be

effected/ carried out by the contractor at his cost, unless a different intention is

specifically and expressly stated herein or otherwise explicit from the context.

01.05 The tenderer shall visit the site before quoting to get himself acquainted with site

conditions, availability of water, power, approach etc, No delay whatsoever shall be

entertained on this account.

01.06 The specification of the products stored will be as per the latest BIS specifications.

02.00 CONSTRUCTION PROGRAMME

02.01 A detailed bar chart showing various activities shall be prepared by the bidders. The work

shall be executed strictly as per the agreed time schedule. The period of completion shall

include, the time required for mobilization and testing as well as rectification, if any,

testing and completion in all respects to the entire satisfaction of the Engineer-in-charge.

02.02 A joint program of execution of work will be prepared by the contractor in consultation

with Engineer-in-charge.

02.03 Monthly / weekly construction program shall be made by the contractor jointly with

Engineer-in-charge based on availability of work fronts and the joint construction

program.

02.04 The contractor shall scrupulously adhere to these Targets / Program by deploying

adequate personnel and construction tools and tackles. He shall also supply all materials

in his scope of supply in time to achieve the targets set out in the weekly and the monthly

program.

02.05 The contractor shall monitor and report about labour and equipment deployed along withthe progress of work done on previous day on daily basis.

03.00 CONSTRUCTION WATER AND POWER

Construction water and power (including the requirement for testing and calibration of

tanks) will not be made available by the owner and the contractor at his own cost shall


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arrange the same without any liabilities on the part of owner. The rates quoted shall be

inclusive of the same.

03.01 The Contractor shall drill the required number of bore wells/ arrange water thru tankers at

his cost.03.02 The Contractor shall arrange his own source of power from their DG set or from SEB

directly without any cost to the owner.

04.00 TESTS AND INSPECTION

04.01 The contractor shall carry out the various tests as enumerated in the technical

specifications of this tender document and the technical documents that will be furnished

to him during the performance of the work. No separate payment shall be made.

04.02 The contractor shall carry out at his cost, all the tests either on the field or through external

laboratories, concerning the execution of the work and supply of materials by the

contractor.

04.03 The work is subject to inspection at all times by the Engineer-in-charge. The contractor

shall carry out all instructions given during inspection and shall ensure that the work is

being carried out according to the technical documents and the relevant codes of practice

during the performance of the work.

04.04 Any work not conforming to the execution drawings, specifications or codes shall be

rejected forthwith and the contractor shall carry out the rectification at his own cost.

04.05 Results of all inspection and tests shall be recorded in the inspection reports, test reports

etc., which will be approved by the Engineer-in-charge. These reports shall form part of

the completion documents.

04.06 Inspection and Acceptance of works shall not relieve the contractor from any of his

responsibilities under this contract.

05.00 SITE CLEANING

05.01 The contractor shall take care to clean the working site from time to time for easy access to

work site and for safety. Working site should be always kept cleared to the entire

satisfaction of the Engineer-in-charge.

05.02 Before handing over any work to the owner, the contractor in addition to other formalities

to be observed as detailed in the document shall clear the site to the entire satisfaction of

Engineer-in-charge.

06.00 COORDINATION WITH OTHER AGENCIESWork shall be carried out in such a manner that the work of other agencies operating at

the site is not hampered due to any action of the contractor. Proper co-ordination with

other agencies will be the responsibility of the contractor. In case of any dispute, the

decision of Engineer-in-charge shall be final and binding on the contractor.


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07.0 SAFETY PRECAUTIONS AND HOT WORK

07.01 Contractor shall have to take all safety precautions for carrying out hot work in the

premises after obtaining hot work permit from location in charge at his own cost as

directed by the Engineer-in-charge. Necessary safety equipment such as safety belts,helmet, etc., and other safety instruments are to be positioned by the contractor and the

same shall be used by the work force as per work requirement. The contractor has to

enforce the same. In addition to the above Contractor shall maintain their own set of

Portable fire extinguishers, hose reel & nozzle for necessary hook up with the nearest

hydrant point in case of emergency.

07.02 Safety distance as per CCE rules and Oil Industry Safety Directorate shall be maintained

strictly.

07.03 All exhaust of vehicle & engines shall be fitted with spark arrestor and all temporary

electrical supplies and cabling should have proper Main Isolator, Distribution board,

ELCB and temporary shade. All cable joints made at site should be properly covered with

insulated.

08.00 Third Party Inspection

08.01 Third Party Inspection will be required for

a. Swivel Joints for Articulated Roof Drain

b. Primary & Secondary Seal

The approved parties for carrying out TPI for a & b are EIL, DNV, BVQI & IRS.


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II. TECHNICAL SPECIFICATION

01.00 SCOPE OF WORK

01.01 The scope of work of the bidder shall include complete design, selection of materials,

preparation of drawings, detailed engineering, supply (except free issue steel plates),obtaining approvals of Engineer in charge/owner, transportation, storage at site,

fabrication, installation, erection, testing, calibration, commissioning and establishing the

required parameters to the satisfaction of HPCL, of the storage tanks inclusive of all

fittings, appurtenances and other attachments there to and sub-assemblies wherever

required. The scope also includes construction of sand pad foundation as well as

installation of cathodic protection system as enumerated elsewhere in the specification.

The complete work shall be done in strict compliance with engineering drawings/ data

sheets, specifications from the below mentioned standards/codes.

API-650, tenth edition, 2000 for above ground tanks.

A list of standards and codes recommended for general guidance is enclosed as

Annexure II.

01.02 The scope of work of the bidder is defined in general and shall include the following

but not limited to the same. The bidder shall also carry out the jobs that are not listed

here but required for completion of the job in all respects as per the specifications,

standards, drawings, codes and instructions of Engineer-in-charge whether

specifically mentioned in the drawing or not.

01.02.01 Loading, handling and transportation of all free issue materials from supply point /

store of work site / Contractors store and return the unused / scrap materials to work

site storage point after completion of the work including supply of all tools, tacklesand accessories etc.

01.02.02 Procurement and supply of materials and consumables as indicated in contractors

scope of supply.

01.02.03 Erection of the tank shell for vertical tanks shall be by hydraulic jacking arrangement.

Fabrication of tank bottom, shell, roof, wind girders, etc. including cutting of plates

and structural sections to required size, edge preparation, rolling, fitting, welding etc.

01.02.04 Design, Supply and fixing of all nozzles, flanges, elbow, bends etc. as per specification

drawings and data sheets. Only standard forged pipe fittings shall be used. Fabrication

and erection of supports for pipes, instruments etc. on tanks.

01.02.05 Design, Supply, fabrication and erection of spiral stairways, catwalk, handrails,platforms, top landing and maintenance platforms, walkway, self leveling type rolling

ladder and track, curb angles etc.

01.02.06 Design, TPI for design,Supply and installation of distributed anode based impressed

current cathodic protection system for tank bottom plates of product tanks at Ajmer &

Jaipur.


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01.02.07 Design, Supply and installation of water risers and ring mains (fixed spray system) and

spray nozzle arrangement around tank in two/three rows i.e., above and below wind

girders.

01.02.08 Radar level gauges for continuous level measurement and RTDs for averagetemperature measurement are envisaged for all the petroleum storage tanks. Suitable

installation provision and mounting arrangements shall be provided for the same as

required by the instrument supplier.

01.02.09 Design, Supply and installation of fixed foam fire fighting system as per OISD

requirement. Piping , Supply & fixing of foam maker, pourer, deflection board, etc.

01.02.10 Radiography, DP test, MP test and all other tests on tanks as per code, drawings and

testing procedures by approved testing agencies apart from routine, visual and

dimensional check. The Contractor shall arrange necessary tools and tackles for

carrying out the tests.

01.02.11 Carrying out hydrostatic, pneumatic, vacuum and other test as specified in

codes/standards using tenderers own equipment.

01.02.12 Calibration of tanks and getting approval from statutory authorities as per IS 2007 -

1974 and IS 2008 - 1961. Calculations and preparation of calibration charts and

submitting to HPCL.

01.02.13 Carrying out roof floatation test for floating roof as per codes/standards.

01.02.14 Design and Supply of appurtenances like nozzles, manholes, vents, hatches, primary

roof drains, earth connections, gauge connection with covers etc. and installation of

these items on the tanks.

01.02.15 Design, supply and installation of Primary & Secondary Roof seal and its accessories as

per specification.

01.02.16 Clearing job sites of all surplus material, debris, scrap, construction equipment etc. asper directions of Engineer-in-charge.

01.02.17 Internal & External painting of Tanks. Accomplishment of any other item of work

required for making the storage tank ready for commissioning.

01.02.18 Quantity of steel given is approximate. Payment shall be made for quantities of plates

laid / erected duly certified by the Engineer at site. Payment of steel plates will be

made basis theoretical weight taken as 7.85g/cc.

01.02.19 Scope of work of the contractor includes construction of tank foundations for all the

tanks. The foundation shall be of stone columns overlaid with Sand filling,

anticorrosive layer & seal coat.

01.02.20 Design & Preparation of all detailed and working drawings for various components ofstorage tanks (Cone ,Open Top & FR) and getting the same reviewed / approved by

HPCL. Supplying of all drawings and documents as specified.

01.02.21 Supply of spares, wearing parts, consumables for two year trouble free operation

where various sizes are involved such as in gaskets, bolts, nuts, studs etc., quantity of

spares shall be 10% but not less than 2 number for each size.


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01.02.22 Supply of gauge Pole sleeve for Floating roof tanks.

01.02.23 Excavation, sand filling ,anticorrosive layer, seal coat, PCC/RCC & other misc civil

works. Supply & erection of fire screen and temporary wall on Fire wall anddismantling/disposal after completion of work.

01.03 The design, fabrication and installation shall be in conformity with regulations of CCOE,

OISD and other statutory bodies.

01.04 Design calculations for complete roof for buoyancy, stability, roof drains, tilting, leg

supports, bleeder vents etc. and getting the same approved by TPI and submission of

the same for HPCLs review.

01.05 Design, Supply, erection & testing of Articulated Roof Drain for Floating roof tank as per

specification. TPI for swivel joints.

02.00 SCOPE OF SUPPLY OF MATERIAL

The scope of supply of contractor/ owner is given below and contractors shall quote rates

based on this.

02.01 OWNERS SCOPE OF SUPPLY : Only Steel Plates as under:

Steel plates of all thickness for bottom, shell, wind girders and floating roof of all tanks.

Steel plates for fabrication of reinforcement pad plates for shell and roof nozzles and

appurtenances. Steel plates for foam dam and shell extension for deflection for foam

pourer. Datum plates under the gauge well pipes, bearing plates for pipe supports.

Incase of Rewari, pipes and valves required for piping work will also be supplied by

HPCL.

However the fabrication of the above plates in the required shape and size is in the

scope of the contractor. It may be necessary to change the thickness and size of steel

plates before commencement of work or during the progress of work, depending on the

availability of steel plates. The contractor shall have no extra claim because of such

changes and shall accept final measurement of the finished job without any allowance

whatsoever.

MS plates in sizes available as indicated below from SAIL/ ESSAR/ LLOYDS/ TISCO/

JINDAL/Others will be supplied to site and the contractor shall prepare fabricationdrawings accordingly for approval, prior to commencement of fabrication work.

Sl. No. Plate Size (LXW) in mm Plate thickness in mm

1 6300 X 2000 8, 10, 10, 12, 14, 16,18

2 6300 X 1500 5, 6, 8


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3 8000 x 2000 5,6,8,10,12,14,16,18

Basis for procurement of steel plates:

1. API 650 has been adopted for the design of storage tanks.

2. Corrosion allowance of 1.5 mm has been considered.3. Minimum thickness of Bottom plates shall be 8 mm and annular plate as 10mm.

The arrangement of steel plates considered for procurement by the owner for different

locations of the storage tanks and the thickness of the same are indicated in the enclosed

drawings. The contractor shall confirm the adequacy of the same.

02.02 CONTRACTORS SCOPE OF SUPPLY: All other materials other than steel plates for

tanks as under:

Materials, consumable/ non-consumable not mentioned under Owners Scope of supply,

but required for satisfactory completion of the job shall be supplied by the contractorinclusive of the following but not limited to the same:

All the welding rods, erection materials, scaffolding, bending and cutting machine,

oxygen, acetylene, grease, oils, labour etc.

The procurement and supply in sequence and at the appropriate time of all materials

and consumables including structural steel (Plates & sections) required for completion of

works as per drawings, specifications and standards except the materials specifically

listed in Cl.no 2.01 above shall entirely be the contractors responsibility. The items to be

supplied by the contractor are in general but not limited to following:

A) All steel plates required for the components other than those listed in Cl.2.1.2.

B) All consumables such as electrodes, filler wires, acetylene, grease, oil, gases,

electricity etc.

C) All structural steel sections wherever required for Cone roof structure,curb angles,

Top wind girders Supports/stiffeners/ extensions for stairways, Top wind girder

bracings, Secondary wind girders, supports for Fire water Cooling Spray Headers/

risers, supports for Foam system risers, spiral stairways, landings , platforms, handrails,

bracing for foam dam, Inlet and Outlet Nozzle Troughs, Gratings(which may be

fabricated by the Contractor at a workshop/ factory outside HPCL premises), stiffeners

for Shell extension and supports for top platform, etc.

D) All pontoon stiffeners for single deck floating roof.

E) Rolling Ladder, internal ladders, hand rail for stairways, ladders, platforms,etc.

F) All seamless pipes for nozzle necks 200mm NB and below, internal pipes, Nozzle

necks for openings more than 200mm,Materials for Inlet/ Outlet Nozzle troughs, floating


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roof supports, bleeder vents, emergency drain, bottom drain extension, extension piping

for roof drain, etc.

G) All pipe fittings, valves, flanges, matching flanges and blind covers wherever

specified for all nozzles, stainless steel wire mesh for emergency drain, brass items and

brazing for Auto bleeder vents.

H) Primary roof drain after (Third Party Inspection for swivels) with associated rigid

piping sections, if any adequately supported on Bottom/ from deck underside, necessary

shoes/ guards, etc as per Manufacturers instructions including swivels, brass non return

valve, extension piping etc.

I) Bolts, nuts and SS spiral wound gaskets for roof & shell manholes, nozzles with blind

cover/ matching flange, bolts & nuts for roof structure and other structural works.

J) Seals (Primary & Secondary) of approved make, guide rollers, roof stoppers, earthingcable, shunts etc. Primary & Secondary seals for MS & ULMS F/R Tanks. Seals shall be

supplied after Third Party Inspection.

K) Rim Vent along with relief valves..

L) Gauge well & Gauge Hatch with cover.

M) Pipes, fittings, flanges and bolts and nuts and spray Nozzles and orifice plates and

structural supports for Piping for Fixed water Cooling spray system.

N) Pipes, fittings, flanges, orifice plates, Foam makers/ Pourers and deflectors on point

of spray on shell and structural supports for Piping for Foam system

O) Support arrangement required for cooling system.

P) Internal Bolts & Gaskets.

Q) Water including CI for hydrotesting & calibration.Strapping tapes & accessories for

calibration.

R) Radiographic Films & Consumables for NDT.

S) Earth connections, support cleats for pipes, structurals & cables.

T) Any Blind flanges, valves, nipples, plugs, bolts, nuts, gaskets, etc required for

conducting hydrostatic testing and any other test required by HPCL.

U) All primer materials and painting materials, scaffolding, blasting medium and

related equipment for Painting.


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V) Brass Plate for sealing still well annular space, Gasket, Gauge Pole sleeve for still well

(W) Providing tools, tackles, hoist/crane, jacks, instruments, supervision etc. required for

completion of the work as per drawing, specification and codes. The contractor shall

hand over test certificates for all items supplied by him to the owner for verification and

approval.

(X) All type of appurtenance for floating roof & shell. All types of paints and paintings

system for A/G Tanks.

(Y) All materials, labor, tools, machinery and accessories required for Civil works related

to Tanks.

(Z) All materials, labor, equipment & accessories related to CP system for tanks

Note:

While every effort has been made to list all the supply items, it shall be the sole

responsibility of the Contractor to review the list and seek clarifications, if any at thetime of Unpriced Bid itself. HPCL undertakes to provide only Free Issue Steel plates

for Fabrication, pipes & valves incase of Rewari, and all the other items shall be

supplied by the Contractor only. No claims/ disputes by the Bidder/ Contractor shall

be entertained by HPCL at a later date. The above items are to be supplied by the

party for Floating Roof, Cone roof & OTVT Tank as applicable. The items have been

covered in SOR & specification, except 10% spares like studs/nuts/gaskets etc which

shall be supplied by the party at the time of handover on the basis of final Bill of

quantities, at no extra cost.

02.03 RECOVERY AND INVENTORY OF STEEL PLATES

02.03.01 Steel plates required for the fabrication and erection of tanks as per the owners scope

of supply will be issued to the contractor by engineer-in-charge with full

measurements. Contractor shall sign and hand over the material receipt to engineer-in-

charge after thorough checking of the same.

02.03.02 All steel plates thus issued shall be strictly accounted by the contractor.

02.03.03 All off cuts and unused plates shall be property of owner and shall be returned by the

contractor to owners store, after weighing all off cuts plates at his cost.

02.03.04 Non-recoverable plates excluding off cuts shall not be more than 0.5% of the erectedplate weight.

02.03.05 Off cuts, unused steel plates non-returned and any excess non recoverable plates

beyond 0.5% of the weight of erected plates shall be recovered at twice the landed cost

of plates from contractors bills.


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02.03.06 Contractor shall be fully responsible for correctness of sizes of plates indicated in the

fabrication drawings to be prepared by him. In case any plate gets damaged/ spoiled

by the contractor due to his fault, cost of the same will be recovered at twice the

landed cost of plates from contractors bills.

02.04 Civil Works

02.04.01 The civil works required for the tanks included under this tender are included in the

scope of the tenderer. Refer to the specification of the civil works part.

03.00 MATERIAL SPECIFICATIONS:

Steel plates for tanks shall conform to IS-2062 Gr. A/B, 1999. Man hole neck rings, bolting

flanges and cover plates shall be fabricated from MS plates conforming to IS 2062 Gr. A/B

1999. Nozzles of all sizes shall be fabricated from seamless pipelines conforming to

specification given in Annexure-I.

All slip on and blind flanges shall be fabricated from SA 105 material. Further they shallconform to ASA class 150 with holes drilled as per ANSI B.16.5.

All structural steel sections for columns, column bases, beams, girders, rafters, curb

angles, hand rails, roof top railings, inter connecting bridges, flat gratings, rolling ladder

with track, rollers, axles, rods and bars shall conform to IS-808 latest edition.

Gauge well pipes shall be seamless pipes for floating roof tank. Gauge hatches shall be ofspark proof aluminium with quick opening cover and locking arrangement. All landing

platform floors, spiral staircase steps, self-levelling steps of the rolling ladder, roof top

platform floors shall be provided with MS flat gratings in honeycomb pattern.

.

Metallic Spiral Wound Gaskets for manholes, nozzles, fitted with blind flanges shall

conform to specification IS 7719 75. Thickness of gaskets shall be 1.5mm up to 300mm

NB nozzle and 3mm above 300mm NB nozzles. However before conducting hydro test

the flange joint shall be provided CAF gaskets. There shall be two numbers of spares for

each size location wise.

Bolts and nuts for all nozzles fitted with blind flanges shall conform to IS 1367 and bolts

and nuts for all structurals shall conform to IS 1363 92.

Gate valves and non-return valves on pressure relief line shall be of forged steel

construction of class 800 conforming to API 602 and BS 5352 respectively.


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Pressure testing shall be done as per API 598/ BS 6755. Pipe fittings shall be of 3000 lbs

rating.

Welding electrodes for all plates of thickness 14mm and above, annular ring to bottomplates and shell to bottom plate welding shall be of low hydrogen (basic coated) as per

AWS classification SFA 5.1. For all other welding high cellulose / rutile type as per AWS

specification SFA 5.1 are acceptable. Advani Orlecon / ESAB/ Phillips / D and H Sechron /

Hanavar / Mailam / GEE make electrodes only shall be used.

Materials listed above shall be considered as minimum qualities for materials. An

equivalent or superior quality may be substituted. No substitution shall be made without

the written consent of Engineer-in-Charge. All materials shall be new, first class quality

and of the type and grade specified.

04.00 DESIGN AND DRAWINGS

Floating /Open roof tanks shall be designed in accordance with API 650, 10th Edition,

2000 and applicable Appendix with latest edition and supplement and the horizontal

cylindrical tanks shall be as per IS: 10987-92.

All basic drawings with design data and material specifications are attached with this

tender document for tendering quotation as listed in Annexure-II. Final drawings with

revisions if any shall be prepared and submitted for review / approval after award of

contract or Purchase order by the contractor.

Floating & Cone roof tanks shall be designed by the contractor considering design data

given in each drawing and calculations shall be submitted for review / approval / records

with regard to following in line with API-650 guidelines.

a) Design calculations / data sheets for plate thickness, stability calculations, wind girders

etc.

b) Buoyancy calculations for roof, calculations for roof drains, bleeder vents etc.

c) Structural calculations for roof leg supports, roof rim plates & Structural supports of

cone roof tank. Venting size calculation for Roof vent of Cone roof and Auto bleeder vent,

rim vent for floating roof tanks.

Design calculations of the tank shall be approved by a competent design agency and shallbe submitted to HPCL.

05.00 FABRICATION AND ERECTION


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Before commencing the job all plates shall be squared, diagonally checked, stenciled and

stacked in order of execution of work. Plates shall be checked for splitting if any

particularly. Split plates or laminated plates shall be rejected. Plates thus prepared shall

be offered for inspection to the Engineer-in-Charge. Contractor shall arrange allequipment and labour necessary for inspecting and measuring all the plates. After the

plates are approved they shall be stencilled and stacked properly. Plates shall be

thoroughly checked for all dimensions and diagonality. Fabrication and erection of the

tanks shall be carried out as per drawings reviewed / approved by HPCL.

05.01 BOTTOM

The underside of bottom plates shall be blast cleaned to SA 21/2 and painted with two

coats of tank mastic paint of approved make before laying. The underside of tank shall be

protected for corrosion by cathodic protection technique.

Bottom plate shall have a uniform slope of 1:50/100. Plates shall be lap welded and the

over lap shall not be less than 5 times the plate thickness unless otherwise specified. For

sketch plates/ annular plates, the overlap shall be given as per the code.

For all tanks diameter more than 13m annular plates shall be provided and these annular

plates shall be butt welded with backing strips. Joints between annular plates and sketch

plates shall be lap welded.

Datum plate for calibration/ gauging of product level in the tanks shall be welded on to

the bottom horizontally to perfect level and directly below the gauge well. Weldingsequence to be adopted shall be indicated in the drawings submitted by contractor and

this shall be followed so as to cause minimum shrinkage and distortion.

Bearing plates of the pipe supports shall be centred under each support for the floating

roof and welded to the tank bottom by continuous fillet weld of size equivalent to plate

thickness. These bearing plates shall be of sizes 600 x 600 x 10mm. Overlaps in joints of

bottom and roof plates will not be measured and paid separately.

05.02 SHELL

All the tanks included in this tender shall be constructed by Hydraulic Jacking uparrangement. All vertical and horizontal shell joints shall be full penetration and full

fusion welds. The shell joints shall be double welded butt joints using any one of the

edge preparation permitted by API 650. Details of the weld and edge cutting shall be

shown in the drawings and shall be approved by HPCL.


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Shell plate arrangement and thickness as planned are as indicated in the enclosed

drawings.

Top curb angle shall be lap welded to the top course of shell with the flange turnedoutwards unless otherwise specified.

Tank heights that are indicated in the tender are nominal and the actual heights might

undergo minor changes to suit the construction.

The stiffening ring or wind girder where necessary shall be welded to the tank at the

location shown in the drawing duly stiffened with gussets and struts welded to shell.

Welding shall be of same quality as used for shell. Primary wind girder shall be provided

as a walkway with all around hand railings. Horizontal portion of stiffening rings shall

be provided with drain holes of 25mm dia. These holes shall have suitable arrangement

so as to avoid rain water from moving to tank shell.

Curb angle and stiffening ring joints shall not come in line with the vertical weld joints of

the shell plate. These joints shall offset each other by at least 1.0M. First shell course

plates shall be so arranged that vertical joints clear the annular ring welds or sketch plate

welds by at least 360mm. Vertical joints of shell course shall also clear the nozzle

attachment welds or reinforcement pad welds as per API 650. Holes shall not be made on

shell plates for erection purpose. Shell plate alignment shall be within the limits specified

in API 650.

D/P test and Oil chalk test shall be carried out for shell to bottom joint. For shell tobottom joint, low hydrogen electrodes shall be used. Internal weld seams of floating roof

tanks shall be smooth and even to allow proper movement of roof without damage to the

seals.

During fabrication contractor shall provide guy ropes and other means to secure semi

finished storage tanks against damage due to wind. Wind girders shall be welded to

tanks at the earliest. The lifting of shells should not be commenced without fixing of wind

girders.

05.03 FLOATING ROOF

Floating roof shall be of pontoon type for diameter more than 12m with multiple

compartments and shall be liquid proof to meet the minimum requirements of API 650.

Each compartment of floating roof shall be provided with specified manhole with cover.

Central deck and pontoons shall be suitably stiffened and calculations for structural


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integrity of floating roof shall be submitted to HPCL for review. Centre deck of the

floating roof shall be fabricated out of 5/6mm thick plates. Pontoon bottom shall be of

6mm plates. Pontoon Roof and compartment plates shall be of 5mm thick plate where the

same shall be 6 mm. Inner and outer rim plates shall be designed by the contractor andcalculations forwarded to HPCL. 16mm and 8mm plates have been considered for the

plate procurement for the inner/ outer rim plates respectively.

Deck shall have permanent slope to the centre to avoid stagnation of rainwater. When

floating roof is in highest position, tank shall be capable of holding its designed capacity.

Foam dam shall be provided with 5mm thick plates, for all the tanks as per standard to

contain the foam to seal area. Floating roof shall be of low deck (minimum vapour space)

type. Central deck of the floating roof shall be provided with two through deck manholes

with ladders. Suitable stainless steel leaf springs shall be provided at the bottom rim of

the deck @ 2.5 m c/c around the periphery for holding the deck centrally. Necessary

stainless steel bolt, nuts, washers, etc, also shall be provided.

05.05 STAIRWAYS, LANDING PLATFORMS AND RAILINGS

05.05.01 Stairways and Platforms

Each tank shall be provided with stairway with hand railing and landing platforms for

access to the roof. Each step shall be supported by a vertical square rod as specified. The

steps shall be fabricated out of MS flats bent in honeycomb pattern. The steps on one

side shall be welded to tank shell. Raised platforms as per size indicated in the standard

drawing shall be provided at the top of the stairway and shall be extended suitably to

permit easy access to the two gauge well pipes for each of the tanks.

A self-levelling rolling stairway shall be provided for access from platform to the

floating roof. Roller track fixed to the roof shall permit movement of the stairway. Brass

rollers for the rolling stairway shall be provided to avoid sparking. The steps for the self-

levelling ladder also shall be of MS flat grating in honeycomb pattern.

05.06 TANK APPURTENANCES

05.06.01 Manholes and nozzles

All manholes shall be according to API 650. The cut edges of the manhole shall be

ground smoothly. The axis connecting both the manholes shall be generally in the

direction of the wind prevailing locally. Shell and deck manholes shall be 600mmnominal diameter. Pontoon manholes shall be of 500 mm nominal diameter. The

dimensions of the nozzle shall be in accordance with API 650 unless otherwise

mentioned in the approved drawings. The out side end of the inlet and outlet nozzles

shall be provided with slip-on flanges to facilitate fixing of the gate valve and the inside

end shall be provided with a semi-circular MS trough as per drawing. Position of the


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nozzles shall be such as to facilitate easy connection to the main running pipeline in the

depot/ installation. Product inlet /outlet nozzle flanges shall be of class 150. Flange holes

shall be drilled as per ANSI-B-16.5. Manhole and nozzle reinforcing pad plates shall be

provided with 6mm threaded tell tale holes for testing purpose. Nozzles shall be weldedto the tank with the same quality electrodes as used for shell welding. Manholes and

nozzles shall be provided with gaskets, nut and bolts as specified.

05.06.02 Floating roof supports

The number of supports shall be sufficient to ensure non-deformity of the roof and tank

bottom when the roof is resting on the legs. The pipe supports shall be provided with

cotter pins as specified in the drawing and suitable for two level operations. For this,

holes shall be provided on the top portion of the legs to adjust the cotter pin. Leg

supports shall be of 80 mm NB seamless SCH 80 pipes and sleeves shall be of 100mm

NB seamless SCH 80 pipes. There shall be two operating levels of 2m and 1.2 m from the

tank bottom plates.

Pipe supports shall rest on the bearing plate after hydro test of tank. These bearing

plates shall be stitch welded 50 to 60 mm c/c. Corrosion allowance shall be provided for

roof supporting pipes and sleeves also.

05.06.03 Roof drain

1.1 The intent of this specification is to cover the scope of design, supply, erection, testing

and commissioning of Swivel Jointed Articulated Roof Drain required for draining rainwater from the roofs of Floating Roof Vertical Tanks for the petroleum products viz

HSD, ULHSD, MS, ULMS and SKO.

1.2 Compliance of this specification will not relieve the tenderer of his responsibility

for supplying the equipment / items of proper design, material and workmanship to

meet the specified operating requirements and also proper workmanship and

performance of the facilities under the contract.

1.3 Any additional material, which are not specifically mentioned in the technical

specifications but are required to make the system complete in all respects for safe

operation and guaranteed performance, shall be included in the scope of work of thetenderer.

1.1 All materials supplied shall be new, of best quality and tested in accordance with the

latest version of the relevant Indian Standards or relevant International Standard and

codes acceptable to HPCL The tenderer shall indicate make and grade of all bought out

items for approval from HPCL.


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1.2 Specification of the products are as given below :

Product HSD ULHSD MS ULMS SKO/ATF

Density at 15 C 0.87 0.86 0.77 0.775 0.84

Viscosity, cst 20 C 8 8 0.7 0.7 1.53

Vapour Pressure,

kg./cm at 38 C

0.1 0.1 0.7 0.7 0.3

Operation

Temperature

50 C

1.3 All drawings and instructions shall be in English language. Dimensions in drawings;

technical data, weights and quantities shall be in metric units.

2.0 SCOPE OF WORK FOR ARTICULATED SWIVEL JOINTED ROOF DRAIN SYSTEM

A. Design, manufacture / fabrication, testing, supply of roof drain system to work site

B. Assembling, transportation at work spot, erection, testing and commissioning of the roof

drain for the storage tanks as per the details given in Bill of Quantities.

The following shall also form scope of work.

i) The tenderer shall supply at his cost all equipment / piping, all necessary skilled

and unskilled personnel, hoists, tools and tackles, instruments, safety

implements and other accessories required for assembly, erection, testing and

commissioning of the Roof Drain system for the tanks.

ii) The tenderer shall give complete calculations for design of drain system,

complete technical specification of the equipment offered and general

arrangement drawings for the approval of HPCL, sufficiently in advance of the

commencement of manufacture. Such approval, when accorded, shall however,


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not relieve the tenderer of his responsibilities towards satisfactory and trouble

free performance of the roof drain system.

iii) All the equipment shall be shop tested according to the relevant standards. The

particulars of the proposed tests shall be submitted to HPCL for approval before

conducting the tests. HPCL shall be given full access to all the tests. The

supplier shall inform HPCL sufficiently in advance so that if HPCL desires, his

representative can witness the tests. All the certificates shall be submitted for

the approval of HPCL before clearance for dispatch of the equipment can be

given.

iv) Tenderer shall furnish certificates for swivel joints, pipes, valves etc forming

part of roof drain system.v) The tenderer shall also additionally supply all necessary spares required during

erection and commissioning, free of cost, for roof drain system.

vi) The tenderer shall furnish to HPCL the complete drawings, documents, test

certificates, etc. as indicated in this technical specification for approval /

information and record.

vii) The tenderer shall guarantee the material, workmanship, and satisfactory

performance of the complete roof drain systems for a period of 5 years from

the date of completion of work. The completion date as mentioned in the

Work Completion Certificate shall be considered as starting date. The partyshall give Performance Bank Guarantee equivalent to the cost of Roof drain

with a validity of 5 years as above from any Schedule Bank.

3.0 TECHNICAL SPECIFICATION

3.1 The tenderer shall design and size the roof drain system for each tank for a rainfall of

100 mm / hr. The system shall be suitable for draining the water collected at the roof

sump through the shell nozzle near tank bottom. For design of roof drain, when the

roof is at low leg the height difference between sump drain outlet of roof and at thedischarge end at outlet may be considered as 1.5 m. The offered roof drain system shall

include / incorporate items / equipment that are well proven, tried and tested for

operation in petroleum storage tanks especially in Indian conditions.


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The satisfactory operation of the roof drain without any damage / leakage shall be

ensured, considering the vertical and sideways movements of the roof while in

operation. The materials of constructions of Gaskets and seals shall be compatible for

operation with the product in the tank. All studs and nuts for roof drain shall be of SS.

3.2 ARTICULATED SWIVEL JOINT ROOF DRAIN :

The roof drain system shall be of swivel jointed type with articulated steel pipes. The

system shall include Swivel Joints (ASTM A105 body with viton seals) Split type Design

having anti corrosive sealing surface & Hardened Ball races to Min 55HRC, Seamless

pipe (ASTM A106 Gr. B Schedule 40), Elbows (ASTM A234 WPB Schedule 40), Flanges

including with matching flanges for the roof drain system (ASTM A105 SORF Class 150),

SS 304 spiral wound gasket, Flanged Non-return valves at roof sumps (BS 1868, Class

150, Cast steel body, brass lining on flap), Supporting structures / legs, fasteners, chains

etc complete in all respects for safe operation of the system. The welding of pipe joints

shall be carried out by ASME section IX qualified welders.

Makes of Pipes shall be SAIL, Maharashtra seamless ltd, Jindal pipes ltd, TISCO, MAN,Welspun, PSL or any other reputed make with the approval of HPCL.

Makes of NRV valves shall be Econo valves Pvt. Ltd., BDK Engineering Industries Ltd.,

Fouress Engineering (I) Ltd., Steel Strong Valves Pvt. Ltd., NSSL Ltd, Shalimar Valves Pvt.

Ltd., Flow Chem Industries, AV Valves Ltd., Audco India Ltd, KSB pumps Ltd or Any

other reputed make with the approval of HPCL. Make of Swivel Joint will be Technika,Associate Engineers, PentaTech or any other reputed make with prior approval of HPCL.

Assembly of Two Swivel Joints & pipes till flanged ends will be purchased from the Swivel

Joint Mfgrs for better concentricity & alignments of the Swivel Joints. Only pipes having

flanges at both ends & structures will be made at site.

Roof Drain will have sufficient joints to take care of Vertical movement of the roof and other

movements such as Rolling, pitching, Rocking about vertical axis or Lateral movements of

the roof. This will be achieved by fixing additional Swivel joints

Note: The location of drain sump on the deck shall be considered at the centre of the

deck. The party should refer the scheme attached with the tender. 8 Nos 6 swivel and 2

Nos 8 swivel has to be provided for the Roof drain per tank.

4.0 INSPECTION & TESTING : Swivel joints along with accessories shall have to be

inspected by Third Party agency at bidders cost prior to delivery at site.


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4.1 The items under the scope of supply of Roof Drain System shall be inspected by HPCL

at the manufacturers or his sub contractors works. The tenderer shall furnish, Quality

Assurance Plan (QAP) he proposes to follow at the factory and the tests to be conducted.

This shall clearly define and identify the stages of inspection, scope of test, list ofdocuments to be furnished.

The tests shall include, but not limited to the following :-

Life cycle test for 20000 cycle of rotation at air / hydraulic pressure of 5 Kg/cm. No

indentation mark on ball races shall be there after dismantling the swivel joint (Type

test).

Swivel joint shall be externally pressure tested at 4 Kg/ cm pneumatically.

Bending moment test for base swivel at 1000 cycle of rotation and hydro test for swivel

joint with bending moment at 15 Kg/ cm pressure for 10 min. No indentation marks

shall be there on ball races after dismantling the swivel joint (Type test).

The tenderer shall arrange all facilities required during inspection and testing at his cost.

HPCL shall have the right to inspect / witness the tests at various stages of fabrication /

manufacture / installation. The inspection shall be carried out at suppliers works / his

subcontractors works / site. Inspection of the item shall be done only with a view to

ensure that the same is manufactured, tested and supplied as per prescribed

specifications. The inspection shall in no way relieve the supplier of his responsibility as

per the contract and shall in no way be binding on HPCL

Manufacturers test certificate shall be furnished for all bought out materials. Wherever

such certificates are not available, the tenderer shall get the items tested at his expense at

government recognized laboratories, mutually agreed upon with HPCL.

Any defects noticed during the inspection / testing at site shall be rectified by the

tenderer at his cost as advised by the site engineer and inspection / testing carried out

for fool proof working.

The roof drain system shall be pressure tested to 50 PSI after installation in the tank. The

contractor shall perform the test in the presence of the engineer-in-charge. Any defects /

leakage observed during the testing shall be repaired by the contractor at free of cost toHPCL.

5.0 DRAWINGS / INFORMATION TO BE SUBMITTED


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The following drawings and documents in two copies shall be submitted along with the

offer. Data sheets / catalogues / literature / drawings of the items offered indicating :

a. Materials of construction and standards for different components of the

roof drain system.

b. General arrangement drawings indicating the lay patterns, cross sectional

drawings and showing the highest and lowest operating level details.

c. Make of Swivel joints, Pipes and NRV.

d. Pipe size considered for roof drain system with sizing calculations.

List of deviations, if any.

05.06.04 Roof vents

Two types of roof vents shall be provided in case of floating roof tank. One is auto

bleeder vent and the other is rim vent. For Cone roof tank, single/multiple Roof vent(s)

of adequate size shall be provided

Automatic bleeder vent of specified size shall be so designed as to open before the roof

touches lowest position and to close when the roof rises above this point.

Pressure vacuum relief valve ((PVRV) type Rim vents shall be provided for venting the

void space between the stored liquid and seal. The connecting pipe shall be fabricated

out of MS ERW pipe as specified, with a slip on flange at the top. PVRV shall be of

Aluminium construction.

05.06.05 Gauge well

Gauge wells with perforations shall be provided from rooftop down to the bottom and

have dimensions as indicated in the detailed drawing. The top of the gauge shall be

provided with an aluminium gauge hatch with cover and fireproof gasket and a flange

for 50mm pipe. Cover shall be spark proof type. The other gauge well diametrically

opposite shall be provided with a SORF flange at top. The gauge well shall be fixed in

perfect verticality by means of angle sections as shown in the drawing.

The well pipe shall extend to the top of stair way platform. 2 Nos. of gauge wells located

diametrically opposite shall be provided for each of the tanks. Gauge well shall be of

200mm seamless SCH 40 pipe. The sleeve provided in the pontoon for the gauge well

pipe should be of 350 mm diameter. 20 mm thick brass flange shall be provided in thesleeve for the gauge well pipes to pass through. 50 mm SCH 40 pipe with flange shall be

provided inside one of the gauge-well pipes for average temperature sensing of

products inside the tanks.


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05.06.06 Roof seal

Primary Seal

Mechanical Shoe Seals comprise a metallic sealing ring, which is held in permanent

contact with the tank shell and extends into the product by a system of independenthanger and pusher mechanisms, and with a continuous sealing apron curtain closing

the gap between the rim and the top of the Shoe. The product vapors are contained

between the shoe , apron curtain and the floating roof.

The design of the Mechanical Shoe Seal should be Channel Hanger Type with

independent hanger and pusher devices. The design of the Mechanical Shoe Seal

should be such that in service installation is enabled with no hot work allowed i.e. no

welding or flame cutting. The Mechanical Shoe Seal should conform tightly to shell

plate contours adaptable to existing rim and shell configuration, including wide

variations in rim gap.

The seal is characterized by a shoe-to-shoe slip joint connection, which allows for any

variation in the rim space irregularities between the rim and tank shell, while

containing the product vapors. It should be custom designed to suit the tank.

The Channel hanger type assembly should successfully maintain a constant seal

elevation even with a wide rim space. Galvanized shoes shall conform to ASTM A 924

and a G90 coating or equivalent and shall have a minimum nominal thickness of 1.5

mm (16 gauge). Stainless steel shoes shall have a minimum nominal thickness of 1.2

mm (18 gauge). Stainless steel shall conform to the requirements of ASTM A 240/A

240M (austenitic type only).

Pusher mechanism should be SS conforming to the requirement of Stainless Steel as

given above.Static Shunt to be SS conforming to the requirement of Stainless Steel as

given above.All fasteners to be galvanized for seals of galvanized construction & SS for

SS construction. Hanger Channels assembly should be minimum 14 gauge.Seal

Curtain/ Dip.Curtain should be compatible with stored product, recommended 0.5mm

thk PTFE. A protective mechanism should be provided to protect the vapor curtain.

VENDOR / MANUFACTURER ELIGIBILTY

Vendor shall have proven experience in supplying & installing the mechanical Shoe

Seal with necessary documentary proof for having executed such jobs. The seal shouldmeet CPCB requirements

INSPECTION CRITERIA :

Maximum seal gap area will be 200 cm2/m of tank diameter.


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Scope of Third Party Inspection:

Seal Curtain: Testing of properties to be witnessed and verified.

Mass of Zinc Coating on Mechanical Seal Components to be witnessed & Verified.Othertests to be carried out at a reputed laboratory and the results shall be furnished for

review / approval.

Secondary Seal

Secondary seal shall be of compression plate rim mounted horizontal or vertical

(preferably horizontal), made from series of metallic sheet joined together to form a

ring with a non-metallic tip that slide on the inside surface of the tank shell. The joints

to be bolted or sliding and to incorporate gasket at the point of overlap of the

compression plate.

Compression plate of the secondary sealing system should be sized to match the

existing annular space between the tank shell & the floating roof. The compression

plate should be clamped on the Rim flat/angle with channels duly galvanized. The

compression plate to have the compression channel gasketing. It should provide Leak

tight joint between the plates. Each seal plate should be sealed with the adjacent plate

in a fashion to eliminate vapor loss.

Galvanized compression plates shall conform to ASTM A 924 and a G90 coating or

equivalent and shall have a minimum nominal thickness of 1.5 mm (16 gauge).

Stainless steel compression plates shall have a minimum nominal thickness of 1.2 mm

(18 gauge). Stainless steel shall conform to the requirements of ASTM A 240/A 240M(austenitic type only).

Static Shunt to be SS conforming to the requirement of Stainless Steel as given above.All

fasteners to be galvanized for seals of galvanized construction & SS for SS

construction.A protective mechanism should be provided to facilitate smooth re-entry

of the secondary Seal onto the Tank Shell in the event of Tank overfilling. Secondary

seal system shall be tight fitted, rim mounted, with a wiper Tip made of a polymer

compatible to the stored product.The Sealing Gasket to be made of a polymer

compatible to the stored product.

Seal shall have very low coefficient of friction, shall not damage or score the tank shell.

Metallic seal components shall have adequate corrosion protection for long life. All

material used in the seal manufacturing shall be tested and certified for extended use in

hydrocarbon products.


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It should be custom designed to suit the tank. Additionally, the secondary seal should

have the following design features,

A. Safely ground lightening strike.

B. Minimize seal gap and shed water to the extent possible.

C. Capable in operating effectively over irregular rim gaps.

D. To install from above the deck without any hot works.

E. Seal material must be compatible with product stored.

F. Non-metallic parts must resist cracking and tearing.

G. Metallic components must resist corrosion.

H. To be able to dismantle the secondary seal, without affecting evaporative loss control

characteristics of primary seal.

I. Secondary seal shall extend from the roof to the tank shell and shall not be attached

to the primary seal.

VENDOR / MANUFACTURER ELIGIBILTY

Vendor shall have proven experience in supplying & installing the mechanical Shoe

Seal with necessary documentary proof for having executed such jobs. The seal should

meet CPCB requirements.

INSPECTION CRITERIA :

Maximum seal gap area will be 20 cm2/m of tank diameter

Scope of Third Party Inspection.

Wiper Tip Material : Testing of properties to be witnessed and verified.

Mass of Zinc Coating on Secondary Seal Components: To be witnessed & Verified.

Tests of other components to be carried out at a reputed laboratory and the

results shall be furnished for review / approval.05.06.09 Settling marker

ISA 50 x 50 x 6 and 100mm long settling markers shall be provided on the tank shell 0.5

m above the bottom plate for taking readings of tank settlement during hydrostatictesting.

05.06.10 Tolerance in fabrication

Shell plate: Plate cutting: +/- 1.5 mm on length +/- 1.5 mm on width


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Shell: For the purpose of tanks to have acceptable appearance and to permit proper

functioning of floating roof, the tank shall have tolerance strictly as specified in API

650-2000.

Floating roof tolerance: Tolerance allowed and annular clearance between shell andfloating roof shall be compatible with requirements specified as per API 650-2000.

05.06.11 Electrical & Automation System:

The tender envisages supply and installation and commissioning of electrical and

automation system of the additional product tankages and integrate with the existing

electrical and automation system of the location. All the tanks in the above Terminals

are provided with Radar Gauge with tank side indicator ,temperature element with

water bottom sensor of Saab make supplied by Automation vendor for the particular

location. The all the tank valves are provided with one MOV and one HOV. The

contractor shall integrate new MOVs with the help of actuator supplier or thru

automation vendor to the existing MOV panels of the system. The existing

automation system at Ajmer and Jaipur has been installed and commissioned by M/s

L & T ( contact person Mr Wagle09821604718) and in Rewari by M/s Honeywell

(contact person Mr Snehal 09860869200) .

The contractor is required to supply the same make or equivalent instruments which

are already installed in the location for easy maintenance and trouble free operation.

06.00 Underground Tank: Not Applicable

07.00 Cathodic protection for tank bottom of above ground product storage tanks07.01 Design of the system

All materials shall conform to relevant BIS and other standards specified. System shall

be complete in all respects to achieve the protection standards specified. These

specifications provide only the basic requirements. It shall be responsibility of the

Contractor to collect and take into consideration all the parameters to develop

acceptable engineering practice for the Impressed Current Cathodic protection system.

The Contractors scope of work shall include but not be limited to:

1. Soil/ Sand resistivity survey and soil/sand chemical analysis in Tank Farm area.

2. Submission and acceptance of soil / sand resistivity report.

3. Submission of design calculations and layout plan for the CP system.4. Certification / approval by a competent authority / agency for the design calculation

and installation procedure.

5. Preparation and acceptance of Detailed Engineering Package.

6.Supply and installation of all equipments/materials.

7. Preparation and acceptance of Testing and Commissioning Procedures.


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8. Testing and commissioning of Impressed Current Cathodic protection system.

9. As Built documentation.

The major equipment covered under the specification shall include polymeric anodes,

reference electrodes, junction boxes (AJB and CJB), test stations / boxes, transformerrectifier units (TRU), power cables, anode header cables, tail cables, cathode header

cables, reference cables etc. The installation work shall include necessary insulating

joints, backfill, epoxy encapsulations, thermit welding / soldering, cable markers etc. The

work of placing the Anodes, connecting the cable etc. shall be carried out along with the

other civil works at the right time and with proper co-ordination with the other

contractors.

07.02 Design Guidelines

The cathodic protection system for the tank bottom shall be specifically engineered to

protect tank bottom structure continuously for a minimum period of 30 years. The CP

system shall be designed for 100% bare steel. The cathodic protection system shall be

ngineered to meet the following protection criteria:

1. The structure to soil potential shall be 0.85V (minimum) to - 1.2 V (maximum) (OFF

condition) with reference to Copper/Copper Sulphate Reference Electrode.

2. Minimum polarization shift of 100 mV measured between the tank bottom metallic

surface and permanent reference electrode in contact with soil.

3. The minimum requirement of cathodic protection current shall be 10 mA / sq. m for

the tank bottom plate.

07.03 Codes and Standards

The cathodic protection system shall be engineered, supplied, installed, tested and

commissioned in accordance with latest applicable standards / recommended practices

of NACE, API, ANSI, BS and IS. In particular, the system shall conform to:API RP 651 1997: Cathodic protection of above ground storage Tanks.

NACE RP0193-2001: External cathodic protection of on-Grade Metallic

Storage Tank Bottoms.

NACE RP0285 : Control of External Corrosion on metallic Buried, Partially buried or

Submerged Liquid storage Systems.

BS CP-1021 : Code of practice of cathodic protection.In addition the work shall conform

to requirements of following regulations. (latestrevision)Indian electricity acts and rules.

CCOE regulations, (Nagpur) Chief electrical inspectorate of the respective state. Indian

petroleum act. Fire insurance regulation.

Equipment and materials shall be engineered, manufactured and selected for use under

the following site conditions:

Ambient Temperature : 50C to 500C : 00C to 500C

Relative humidity : 95% maximum : 95% maximum

Climate description : Tropical / Marine normal corrosive or saline soil


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: Tropical normal corrosive soil

The cathodic protection system shall be engineered for continuous operation under the

above site conditions and fully tropicalized.

07.05 Materials and Construction07.05.01 General

Requirements of major equipments are indicated in these specifications. However

contractor shall submit detail specifications of each equipment. All equipments shall be

new and procured from approved and reputed manufacturers. Contractor shall offer

only equipments which have proven service track record and a reference list of similar

make / type shall be provided. As far as possible, all equipments shall be located in safe

areas. Any equipment required to be installed in hazardous area shall satisfy all

requirements dictated by the hazard classification of area in which the equipment and /

or materials are to be installed. It will be ensured that manufacturer of installed electrical

equipments, incorporates all statutory safety provisions. Electrical equipment and

materials for use in hazardous areas shall be certified by an approved certifying

authority such as CCOE/CMRS.

07.05.02 Anode

The distributed anode design shall be based on soil resistivity survey data, external

bituminous padding / sand padding and other specification of tank foundation. The

number and configuration of distributed anodes will be determined by total current

requirement of structure to be protected and optimum current density of the anode

material selected. It shall be so engineered that a uniform and ample current distribution

will be obtained. Anode material shall be carbon based conductive polymer cable

(factory packed carbonaceous material) or equivalent of reputed make with provensupply records of use in Storage Tank Bottom plate cathodic protection. It is preferred to

avoid splicing of anodes in the sand pad foundation.

07.05.03 Transformer Rectifier Unit

Cathodic protection system of each tank shall be in general powered by a separate

transformer rectifier unit. In some cases 2 tanks can be combined for a single power

source. However, voltage drop shall be checked to be within the tolerance. Transformer

will be double wound, air cooled type with electrostatic shield between the windings.

The transformer insulation will be F class. It shall be floor mounted, suitable for indoor

installation and shall be dust / vermin proof. Transformer rectifier unit shall be sized tocater to the protective current demand required for installation with 100% spare

capacity. The DC output voltage of rectifier unit shall not exceed 50V. The rectifier shall

have continuous reading flush mounted DC voltmeter and ammeter for measuring

output voltage and current. Meters shall be accurate and shall be linear from zero to full

scale. Rectifier will be silicon type with adequate cooling arrangement and with


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moisture and humidity resistant finish. It will be mounted on suitable supports.

Adequate filtering arrangement will be provided to limit the ripple content to less than

5% at rated output. The Input/ output of rectifier units will be protected by fast acting

fuses of suitable ratings. Transient surge suppressors will also be provided across. DCoutput terminals and AC input terminals to protect the rectifier against surges. Each

diode and SCR will be provided with suitable surge suppressors. The TRU shall be

equipped with a circuit breaker for the incoming power supply. Power supply to TR

units will be drawn from the feeders of PMCC provided in the Terminal / Depot at 415V,

50 Hz. All the CP TR unit panels shall be located in a room earmarked for the panels.

A) Auto Mode

The unit will be generally working in this mode. The operation of the unit in this mode

will be controlled by upto three reference signals, which will be fed simultaneously. The

unit will have fully solid state Automatic Reference Selector logic to select the least

protected reference out of the three reference signals. The output DC voltage of the unit

in this mode will vary right from 0 V to 50V and from 0A to 50 A (or 75 A as the case

may be) to maintain all the reference signals within the protected range under all

operating conditions. The response of the unit will be instantaneous in order to suppress

extremely fast acting external stray currents. The typical reference regulation in this

mode will be within + 10 mV under all conditions. In case of failure of any reference

signal, the unit will ignore that signal and provided an alarm to indicate failure of that

particular reference input. However, the operation of the unit will not be affected in any

manner due to failure of any of the reference inputs. The unit will continue maintaining

the remaining healthy signals at the protective level. In event of failure of all reference

signals, the unit will provide alarm All Reference Fail and output of the unit will be

adjusted to preset value which will be operator adjustable from 0 V to rated value.Facility will also be provided for manual selection of any one of the three reference

inputs for control. Suitable metering arrangement will also be provided to monitor all

the three external reference signals as well as the internal reference signal

independently. Independent fast acting electronic current limit circuit will be provided

to limit the output current of the unit in Auto Mode to any value from 0 A to rated value

as desired by the operator.

B) Automatic Voltage Current Control mode (AVCC) mode

This will be the second mode of operation. The working of this mode will be

independent of the Manual mode and failure of the unit in Auto mode will not affect

operation in this mode. The output voltage of the unit will be adjustable to any valuefrom OV to rated voltage by means of step less voltage setter. The set voltage will be

maintained within 1% of the set value for change in line voltage from 180V to 270 V

and change in load from zero to full load. The output current of the unit will be

adjustable to any value from 0A to rated value by means of a step less current setter. The

current will be regulated within + 1% of the set value for change in line voltage from 180


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V to 270V and change in load within the specified limits. The response of both current

controller and voltage controller will be ultra fast, instantaneous type there will be no

change in output voltage and current even for a step change in load and input.

C) Manual modeThe control of output in this mode will be without any electronic component. A separate

Auto Transformer with tappings will be provided for voltage control in this mode. The

output will be adjustable from OV to rated value in steps.

Annunciation system

Complete annunciation system will be provided to indicate the followings

1. Under protection.

2. Over protection.

3. Over current (Automatically adjustable over complete range).

4. Ref. 1 fail.

5. Ref. 2 fail.

6. Ref. 3 fail.

7. All Ref. Fail.

8. Reference 1 lowest.



11. Subsequent reference electrodes

The transformer rectifier unit shall be provided with current interrupter to facilitate

recording of ON/OFF structure-to-soil potential.

07.05.04 Test station / box

The test boxes shall be used for potential measurement. It shall be installed near each

tank at four different locations. Test box shall be flameproof, weatherproof, with push-button and DC voltmeter suitable for outdoor installation in hazardous area. Test box

shall be made of aluminum alloy (LM-6) or stainless steel. Test box shall be suitable for

mounting on MS support. A minimum of 30% spare terminals shall be provided in each

test box. DC voltmeter with scale 0-3V shall be incorporated in the-test box for taking

potential measurement. The accuracy of voltmeter shall be not less than + 1%. The

nameplate of test box shall carry following information:

Test box number. Test box connection scheme.

07.05.05 Permanent reference cells

High purity Copper / Copper Sulphate Reference electrodes with proven high reliabilityshall be provided for stable structure to soil potential measurement. The permanent

reference electrode shall have negligible drift in its lifetime and should have a stability of

0.1%. The life of half cell permanent reference electrode shall be comparable with the

design of CP system. Permanent Copper/Copper sulphate reference electrode shall be

Stelth 2 of M/s Borin / Harco of USA. A minimum of six permanent reference


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electrodes for tank dia > 30 m and three for tank dia < 30 m shall be located underneath

the tank bottom plate at the following locations:

- At the center of bottom plate

- Near the rim of the bottom plate- In between center and the rim of the bottom plate.

07.05.06 Anode Junction Box

Anode Junction Box shall be made of stainless steel or cast aluminum alloy having

degree of protection lP55. It shall have arrangement for terminating main positive and

negative cables. The anode junction box shall have current divide facility and measuring

shunt for current measurement. The anode junction box shall beflameproof/explosion

proof, if installed in classified area.

07.05.07 Backfill (If required)

The backfill material of anode cable trench shall consist of charcoal/coke powder having

minimum carbon content of 80 to 90%. This additional charcoal / coke shall be provided

in the trench so that anode cable sets embedded with charcoal / coke. Above it normal

soil available in the foundation shall be provided.

07.05.08 Cables

All cables used for cathode and anode header circuits (including test leads) shall be 1100

V grade, single core, copper conductor, and PVC insulated GI wire armored cable. The

reference electrode cable and anode lead wire cable shall be 1100V grade single core

standard copper conductor with a double insulation system. The primary insulation

shall be PVC sheathing jacket over the primary insulation. The minimum cross section

shall be as follows:

Copper conductor:Test Lead cable 6 mm2

Anode and Cathode header cable (for tanks 48 m dia and below)35 mm2Anode and Cathode header cable (for tanks 64 m dia and below)50 mm2

Anode lead cables 16 mm2

Cathode lead cable 16 mm2

Reference electrode cable 6 mm2

Multi core reference cable 1.5 mm2

07.06. Soil Resistivity survey

The contractor shall carry out soil resistivity survey of the tank farm area and shall study

the details of all backfill materials used for the entire tank foundation and accordingly

judiciously select the design soil resistivity data. To carry out soil resistivity

measurement, Wenners 4-pin method shall be used. Contractor shall also carryout teststo check the presence of chlorides and Sulphate Reducing Bacteria.

07.07 Laying and installation

07.07.01 Installation of Anode (Cable)

The anode cable is to be installed beneath the tank bottom with normal cable laying

technique. A proper coke fill around the anodes has to be ensured. Anode cable shall be


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laid in trench approximately within 1 m depth from the tank bottom. A perforated PE

pipe shall be used as a conduit through gravel and concrete foundation ring in order to

provide mechanical protection to the cable. The anode cable shall be in individual loops/

single cable with each loop / cable extending outside tank wall. This will help to powereach anode cable / loop individually and to access as required. The CP Contractor will

provide a detailed methodology of laying the anodes in foundation for owners

approval.

07.07.02 Laying of PVC pipe for monitoring of Tank to Soil potential using portable

reference electrode

A perforated PVC or FRP pipe will be provided for getting a continuous profile of tank

to soil potential from the perimeter to the center. The pipe will be laid from the

perimeter of the tank to the center of the tank during the period of installation of

permanent half cell itself. The pipe will be installed at shallow angle so as to reduce IR

drop and perforated in a manner that it allows to be temporarily flooded. The intent of

this arrangement is that a submersible Copper / Copper Sulphate electrode can be

inserted into the pipe using stiff wire or small diameter pipe to obtain a profile of tank to

soil potential across the tank bottom. The open end of the pipe shall have arrangement

of plugging through threaded socket.

07.07.03 Installation of Permanent Half Cell

Minimum of three nos. of permanent half cells per tank shall be installed at a suitable

depth preferably at a depth of 300 mm from the tank bottom plate so as to provide a

close measurement of structure (tank bottom) to soil potential. The lead wires from the

reference electrodes will be corrosion resistant type and will pass through PE /PVC pipe

laid from the tank outer foundation ring to tank center place. These wires will then

properly be laid upto the Test box for termination.07.07.04 Cable to structure connection

All cable connections to the tank bottom plate / structure shall be made by an exothermic

process, CADWELD, THERMOWELD or equivalent method.

07.07.05 Installation schedule

The installation of cathodic protection system shall be broadly grouped in following

manner:

Laying of main anode cable beneath the tank bottom. This work shall be scheduled to

undertake during the tank foundation construction. The jobs may be planned in the

following manner:

a) During the construction of tank foundation, the construction of foundation is haltedwhen it is at desired height from the level of tank bottom plate for laying the anode

cable.

b) Laying of anode cable as per engineered configuration will start with normal cable

laying technique using manual excavation.


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c) The cable shall be laid extending the tank concrete foundation ring with cable passing

through a perforated PE duct put on the gravel portion and upto the concrete

foundation ring of the foundation.

d) The cable ends appearing outside the foundation ring shall be properly sealed so as toimpede any water or soil ingressing the cable. The protruded cable ends so protected

shall be kept temporarily embedded in with proper marking so as to locate afterwards.

Similarly laying of permanent half cells, intent to monitoring CP system shall be

completed at this stage only. The permanent half cell wires shall be taken though a hard

PE pipe similar to the arrangement detailed above.

e) Once completed the foundation work of this tank will restart, the cable laying activity,

shall resume in other tank in the similar manner as described in the foregoing.

f) The other activities like Anode junction box installation, all cable laying work, cathode

cable, test lead cable jointing tank body, test lead boxes etc shall be undertaken after

completion of tank painting jobs. This measure is considered to avoid any potential

damage to cable and other equipment of the CP system intended to install in the Tank

Farm Area.

g) While details in foregoing para are kept pending, the installation of TR unit in the

Tank Farm MCC room/ CP Panel room including all its related civil work and electrical

interconnection with MCC shall be taken up consequent to the completion of anode

cable laying work.

07.08 Civil Works

All civil works associated with complete Impressed Current Cathodic Protection system

are included in the scope of contractor. This shall include making cable trenches and

foundation of all equipments, Anode junction box, test boxes and minor civil works. etc.

07.09 CommissioningThe installed CP system shall be commissioned as per approved testing / commissioning

procedures and by following model:

Before the energisation of CP unit, natural structure to soil potential value shall be

recorded at test station of each tank. After taking natural soil to tank potential, the CP

output for the relevant tank shall be switched ON. Output current of the TR Unit shall

be adjusted to achieve the maximum potential value of - 1.5V with respect to copper /

Copper Sulphate Electrode for at least 48 hours.Output current of anodes shall be

adjusted. CP station output of the respective tank shall be set at the designed values.

Observation of structure-to-soil potential shall be recorded at each of the installed test

station. CP station operating parameters shall be recorded. Utmost care shall beexercised to allow the structure to polarize before structure to soil potential values are

recorded across the span for the tank bottoms Structure to soil potential measurement

with both ON / OFF potential method shall be repeated after 15 days of polarization

using current interruption technique. The maximum OFF potential shall be 1.2 V. As a

result of these tests / commissioning if any deficiencies are found in the system, the same


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shall be rectified by the contractor at no extra cost or time effect, to the complete

satisfaction of the Owner/ Owners representative.

07.10 Credentials of CP Contractor and Preferred makes

The Contractor for carrying out the Cathodic protection system shall have a proventrack record of minimum 5 years of designing, installing, testing and commissioning of

similar jobs for above ground storage tanks. Relevant documentary proof shall be

furnished for verification of the experience. In the absence of these credentials this

portion of the tender will not be evaluated.

Preferred makes: Polymer anodes : Raychem / Matcor USA

TRU : Canara electric controls.

Reference electrodes : Borin USA / Harco USA.

Polarisation Cells : Kirk.

Cables : CCI / Fort Gloster / RPG / Special Cables /Nicco

Universal Surge Arresters : Dehn + Sohne Germany.

Junction Boxes : FEPL / Sudhir electrical / FCG GEAG / Baliga

The tenderer can indicate alternate makes, with process performance for the above

items,

which will be subject to evaluation / approval by client / consultant.

08.00 INSPECTION

08.01 ACCESS FOR INSPECTION

Inspection shall be co-ordinated with the Engineer-in-Charge at all times. All tanks shall

be offered for inspection to Engineer-in-Charge in stages as desired by him. In-Charge

shall have free access to all works at all times. The contractor shall provide all tools,

equipment and labour to the Engineer-in-Charge for proper inspection. All inspections

will be carried in accordance with the requirements of this specification. Approval ofEngineer-in-Charge shall in no way relieve the contractor of his responsibilities for

proper execution of works.

08.02 lnspection and Testing of Cathodic Protection Equipment at Manufacturers Works

All components / equipments of Cathodic protection system shall be subjected to

minimum testing and inspection requirements, manufacturers works, as per relevant

codes and standards in presence of Contractor. Owner reserves right to depute his

representative for inspection/testing. The manufacturer/contractor shall furnish all

facilities to Owner for entry to respective works and for testing / inspection at his own

care and expense. Minimum 15 days notice shall be given for inspection.08.03 Field Testing of Cathodic Protection syste

technical specification tankage

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