ASSAM POWER DISTRIBUTION COMPANY LIMITED. OFFICE OF THE CHIEF GENERAL MANAGER (HQ),APDCL BIJULEE BHAWAN, PALTANBAZAR, GUWAHATI

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2 ASSAM POWER DISTRIBUTION COMPANY LIMITED. OFFICE OF THE CHIEF GENERAL MANAGER (HQ),APDCL BIJULEE BHAWAN, PALTANBAZAR, GUWAHATI Tender Notice No: 14/7 Sealed offers with validity up to 365 days from the date of opening of tender supported with particulars, illustrated drawing and literature, delivery schedule, type test certificates, order executing details, user s performance certificates, average minimum quantity manufactured per year, annual turn over etc are invited from manufacturers/authorised dealer/supplier are invited for the following item. Technical qualified participants will be eligible for registration as vendors of APDCL for further supplies as per approved rates. Sl No Items Unit Tentative Qty. Required 1 11 kv D.O fuse set kv G.O fuse set kv D.O fuse set kv G.O fuse set G.I WIRE 6 SWG kg G.I WIRE 8 SWG kg HT Stay set set LT Stay set set Stay wire 7/10 kg Stay wire 7/14 kg Disc insulator 70KN each Disc insulator45kn each kv HT Pin insulator each kv HT Pin insulator each LT shackle insulator with set 2041 hardware fitting 16 LT Pin insulator No HT Guy insulator No LT Guy insulator No LT G.I Pin No KV GI Pin No kv G.I Pin No kv L.A, 30KV 10KA set 60 (Class-2 Polymer) kv L.A, 30KV 10KA set 30 (Class-2) kv L.A, 9kV 5KA set 471 (Polymer metal oxide gapless) kv L.A, 9kV 5KA set 314 (metal oxide gapless) 26 Back clamp for V cross arm No kv V cross arm No Pole top bracket No. 60 Security Deposit. Last date and time of sale of tender 20,000/_ 10/09/14 22/09/14 Date and time of submission & opening of Techno- Comm Bid. 2

3 29 MS Channel X Arm (100x50x50x6)mm x 5000mm 30 MS Channel cross arm (100x50x6x3200mm) 31 MS Channel cross arm (100x50x6x2200mm) 32 LT angle cross arm (75x40x6x1020mm) No. 150 No No. 785 A non-refundable documentation fee of Rs. 5,000/-(Rupees five thousand) only by crossed demand draft/ Banker cheque in favour of APDCL, payable at Guwahati shall be submitted for registration and participation in the tender before the due date for opening of the tender. The Security Deposit of Rs 20,000/- should be in the form of D.D or B.G from any nationalised bank of India, homebranches/regional offices situated within Guwahati & cover the validity period is to be pledged in favour of the APDCL, payable at Guwahati. The Security Deposit of technically qualified firms shall be retained till such period, they remain as approved vendor of APDCL. The APDCL s General Conditions of supply & Errection and Additional Terms & Conditions are enclosed for guideline. The under signed reserved the right to reject any/ all tenderes without assigning any reason thereof. Chief General Manager (HQ),APDCL Memo No. CGM(HQ)/Mat/Line Material/2014/ Copy to: - Dated. 1. PS to CMD, APDCL, for kind appraisal of CMD. 2. The Member (T), APDCL, for kind information. 3. The CGM (D), APDCL,UAR/CAR/LAR, for kind information. 4. The CGM( F&A) APDCL, for kind information. 5. The AGM (F&A), APDCL, O/o of the CGM(HQ) APDCL, for kind information. 6. M/s They are requested to submit their Bid along with terms and condition and delivery schedule within the stipulated period. Chief General Manager (HQ),APDCL 3

4 ASSAM POWER DISTRIBUTION COMPANY LIMITED. OFFICE OF THE CHIEF GENERAL MANAGER (HQ),APDCL BIJULEE BHAWAN, PALTANBAZAR, GUWAHATI No. CGM(HQ)/Mat/Line Material/2014/ Sub: Publication of Tender Notice. Dated. Tender Notice ASSAM POWER DISTRIBUTION COMPANY LTD. Tender Notice No: 14/7 Sealed tender in two parts (a) Techno-commercial bid and the (b) Price bids with validity upto 365 days from the date of opening of tender particulars are hereby invited from manufacturers/authorised dealer/supplier for supply of different type of materials. Bid value: Rs 5,000/- Interested manufacturers/authorised dealer/supplier may obtain the Bid documents from office of the CGM(HQ), material Section, 6th floor, Bijulee Bhawan, paltanbazar, Guwahati- 1. Details can also be seen in the APDCL s official website Chief General Manager (HQ),APDCL Memo No. CGM(HQ)/Mat/Line Material/2014/ Copy to: - Dated. 1. PS to CMD, APDCL, for kind appraisal of CMD. 2. The Director (T), APDCL, for kind information. 3. The CGM (D), APDCL,UAR/CAR/LAR, for kind information. 4. The CGM( F&A) APDCL, for kind information. 5. The O.S.D to the CMD. He is requested to upload the tender notice in APDCL website. 6. The Public Relation Officer, APDCL, Bijulee Bhawan, paltanbazar, Guwahati-1,He is requested to publish the tender Notice in one issue of a National and Local daily in English news paper. 7. Relevant file. Chief General Manager (HQ),APDCL 4

5 Additional terms and conditions 1. Offers from the manufacturers / authorized supplier only shall be considered. The validity of offer should be for a minimum of 365 (three hundred sixty five) days from the date of opening of price bid. 2. The tender should be in two parts, i.e. (i) Techno commercial Bid, (ii) Price Bid. Techno commercial bid: In the techno commercial bid, the tenderer shall submit (i) Security Deposit (ii) Other Technical details along-with Type test certificate: from recognized Govt. approved test house (iii) Drawings (iv) Validity of offer (v) Terms of payment (vi) Delivery schedule (vii) Annual turnover (viii) Order executing details (ix) Users' performance certificate. All documents should be submitted in two (2) sets. (Original & duplicate). Price bid: The price bid should distinctly indicate the following clause - Quoted price with clear differentiation of Ex-factory price, Freight &.Insurance and Taxes and Duties, Entry Tax etc. Techno commercial bid and Price bid (Two copies each) are to be submitted separately under two separate sealed covers superscripting Tender no., Name of bidder, due date, etc. In case of Techno commercial bid the earnest money should be superscripted on the body or the sealed covers. 3. The Security Deposit must be submitted with the Techno commercial bid. The Security Deposit should in the form DD/BG cover the validity period preferred for guidline. 4. The Techno commercial bid shall be opened on the due date and due time (or on the next working day, in case of holiday) in presence of the tenderers or their authorized representatives.the bid shall consists of information of all Technical Bidding Schedules (GTP), copy of licenses, financial turnover, experience certificate, PAN etc. The Price bids of techno- commercially approved tenderers will be opened on a separate date after due intimation. 5. The tenderers are to quote FIRM rates. 6. Telegraphic / Telex offer shall not be considered and tenders received after the due time even though posted earlier shall not be accepted. The undersigned shall not be responsible for any postal delay. 7. Post revision of quoted rates, terms and conditions having direct or indirect impact on the quoted rates shall not he accepted and the offer would he rejected and earnest money shall he forfeited. Withdrawal of offer within the quoted validity period shall not he accepted and earnest money shall be forfeited. Purchaser reserves the right for negotiation or rates, Terms and Condition only. 8. Tenderers should furnish order execution details of items of similar specification for a minimum of last 3 years. 9. Each and every paper of the tender / bid should be signed affixing their seal by the tenderer while submitting tender / bid. 5

6 10. In comparing bids and making awards, the purchaser consider such factors as compliance with specifications, relative quality and adaptability of suppliers of services, the technology and process involved in production experience, financial soundness, records or integrity in dealing ability to furnish repair and maintenance services. 11. All other terms and conditions as mentioned in the APDCL General Conditions of Supply and of supply in contravention or the above conditions will remain in force. 12. Delivery being the essence or the contract, the tenderers should preferably quote their delivery to commence within one month from the date of placing of letter of intent / order and to be compiled approximately within three months thereafter at uniform rate in a phased manner. Tenderers may be asked to re-phase delivery schedule as per requirement or APDCL. 13. The materials are required for various plan and non-plan schemes. The purchaser reserves the right to reject any / all tenders without assigning any reason thereof, the right to accept any tender or part of which is advantageous to APDCL and to award the contract to one party or Spilt up amongst the different bidders. 14. Only those bidders whose Part-I Bid i,e Techno commercial Bid (Qualification) is found acceptable shall be considered for opening of Price Bid. The date and time of opening of Part-II Bid (Price) shall be communicated to those bidders whose bids are qualified for opening. 15. The bidding documents are not transferable and cost of bidding document is not refundable under any circumstances. Chief General Manager (HQ), APDCL 6

7 PRICE BID FORMAT (To be filled by the Tenderer) Sl No Items Offered Qty. Rate per free door delivery by road at our stores, inclusive of loading, unloading, forwarding, stacking freight & insurance etc. (Excise Duty and Taxes extra) (In Rs) (Words and Fingures) 1 11 kv D.O fuse 2 11 kv G.O fuse 3 33 kv D.O fuse 4 33 kv G.O fuse 5 G.I WIRE 6 SWG 6 G.I WIRE 8 SWG 7 HT Stay set 8 LT Stay set 9 Stay wire 7/10 10 Stay wire 7/14 11 Disc insulator 70KN 12 Disc insulator45kn kv HT Pin insulator kv HT Pin insulator 15 LT shackle insulator with hardware fitting 16 LT Pin insulator 17 HT Guy insulator 18 LT Guy insulator 19 LT G.I Pin KV GI Pin kv G.I Pin kv L.A, 30KV 10KA (Class-2 Polymer) kv L.A, 30KV 10KA (Class-2) kv L.A, 9kV 5KA (Polymer metal oxide gapless) kv L.A, 9kV 5KA (metal oxide gapless) 26 Back clamp for V cross arm kv V cross arm Guwahati Tezpur Jorhat Silchar 7

8 28 Pole top bracket 29 MS Channel X Arm (100x50x50x6)mm x 5000mm 30 MS Channel cross arm (100x50x6x3200mm) 31 MS Channel cross arm (100x50x6x2200mm) 32 LT angle cross arm (75x40x6x1020mm) Break-up prices per unit. For door delivery by road should be as below:- Destination stores: Guwahati Tezpur Jorhat Silchar Ex. Factory price...rs Excise duty...%...rs VAT...%...Rs. CST...%...Rs. Freight & Insurance Charge...Rs Total...Rs Entry tax... % Rs. Total Landed cost...rs (Separate sheet may be enclosed for different items.) Signature of Tenderer. (With seal, Address and Contact No.) 8

9 TECHNICAL SPECIFICATION 9

10 TECHNICAL SPECIFICATION FOR 11 KV DROP OUT TYPE EXPULSION FUSE DISCONNECTS to be filled by the Bidder General A.1 Tenderes Name and address - A.2 Manufacturer' Name and address - A.3 Validity of tender - A.4 Guaranteed delivery schedule - A.5 Terms of Payment System details A. Particulars of system details 1.1 Type : 1.2 Number of pole : 1.3 Rated current continues : 1.4 Rated Voltage : 1.5 Rated maximum voltage : 1.6 Short time rating of fuse units : 1.7 Standard MVA Ratings : 1.8 Nominal frequency : 1.9 Particulars of fuse contact i) Materials : ii) Type : iii) Contact pressure : iv) Contract contact : v) Bottom contact : 1.10 Particulars of terminals connectors i) Materials : ii) Dimensions : iii) Type : iv) No. of bolts : v) Size of groves of finish : vi) Base materials : 1.11 Particulars of fuse carrier i) Type : ii) Materials & size : 1.12 Temperature rise of terminals contact corresponding i) At maximum continuous rating : ii) Short time ratings : 10

11 iii) Type of mounting : iv) Centre distance between phase : v) Minimum clearance between live part & earth : 1.13 Anticorrosive provision i) Ferrous parts : ii) Non-ferrous parts : 1.14 Weight of one units including Accessories : 1.15 Particulars of insulators i) Name of manufacturers : ii) Type : iii) Height of insulators : iv) Number of unit per stack : v) Creep age distance : vi) Weight of unit : vii) Weight of non-ferrous part : 1.16 Total weight of one unit : 1.17 Guarantee : 1.18 Reference drawing number : Signature of Tenderer 11

12 SCHEDULE OF GURANTEED TECHNICAL PARTICULARS OF 11 KV G.O.A.B SWITCH to be filled by the Bidder General A (i) Tenders Name and address. A (ii) Manufacturer s name and address. A (iii) Validity of tender. A (iv) Guaranteed delivery schedule. A (v) Terms of payment. 1) PARTICULAR OF INSULATORS : a) Type of Insulator : b) Name of Manufacturer of Insulators. : c) Height of Insulators : d) Diameter of largest shed number of unit per stack : 2) ELECTRICAL CHARACTARISTIS : FOR INSULATORS Flashover voltage. a) Dry frequency : b) Wet power frequency : c) Impulse voltage of 1/50 Microseconds (+) : d) - do - But (-ve) : 2.2. Power frequency withstand of unit : 2.3. Mechanical characteristics. a) Cantilever strength upright. : b) Cantilever strength under. : c) Torsinal strength : d) Tensile strength : 12

13 e) Compression strength : 2.4. General characteristics. a) Minimum crepage distance. : b) Weight of one unit : 2.5. Standard to which insulators conform : NOTES: Values of insulators are given in Metric unit and for one insulator only. Signature with seal. 13

14 TECHNICAL SPECIFICATION FOR 33 KV DROP OUT TYPE EXPULSION FUSE DISCONNECTS to be filled by the Tenderer General A.1 Tenderes Name and address A.2 Manufacturer' Name and address A.3 Validity of tender A.4 Guaranteed delivery schedule A.5 Terms of Payment KV DROP OUT FUSE 2.1 Standard applicable : 2.2 Type : 2.3 Rated voltage (KV) : 2.4 Rated normal current : 2.5 Rated frequency : 2.6 Rated lightning impulse voltage (KV) i) To earth and between pole : ii) Across the isolating distance : 3.0 Power frequency one minute withstand voltage (KV) i) To earth and between pole : ii) Across the isolating distance : 4.0 Rated short time current for 1 sec- (KA) : 5.0 Rated off load breaking current (A) 6.0 Rated active load breaking current (A) : 7.0 Rated line charging breaking current (A) : 8.0 Rated peak withstand current (KA) : 9.0 Electrical endurance : 10.0 Mechanical endurance : 11.0 Minimum Creepage distance : 12.0 Total weight : 13.0 Temperature rise : 13.0 Total weight of one unit : 14.0 Guarantee : 15.0 Reference drawing number : Signature Designation of Signatory Date: 14

15 General A (i) Tenders Name and address. A (ii) Manufacturer s name and address. A (iii) Validity of tender. A (iv) Guaranteed delivery schedule. A (v) Terms of payment. TECHNICAL SPECIFICATION FOR 33 KV G.O.A.B. SWITCH 1.0 SYSTEM DETAILS 1.1. Nominal system voltage : 1.2 Highest system voltage : 1.3 Nominal frequency : 2.0 GENERAL SPECIFICATION 2.1 Rated Voltage : 2.2 Rated Frequency :. 2.3 Rated normal current : 2.4 Rated lightning impulse withstand voltage : i) To earth and between poles. : ii) Across the isolating distance : 2.5 Power frequency one minute withstand voltage : i) To earth and between poles. : ii) Across the isolating distance : 2.6 Temperature rise : 2.7 Rated short time current 1 sec. : 2.8 Rated active load break capacity : 2.9 Rated line changing breaking capacity : 2.10 Rated Peak withstand current : 2.11 Electrical Endurance : 2.12 Mechanical Endurance : 2.13 Minimum insulator creepage distance : 2.14 Total weight of one unit : 2.15 Guarantee : 2.16 Reference drawing number : Seal with Signature 15

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17 SEAL & SIGNATURE OF THE TENDERER 17

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23 SEAL & SIGNATURE OF THE TENDERER 23

24 TECHNICAL SPECIFICATIONS STAY WIRE ( 7/10 & 7/14 SWG ) 1.0 Application Standards Except when they conflict with the specific requirements of this specification, the G.I Stay Stranded Wires shall comply with the specific requirements of IS: IS: & IS: or the latest versions thereof. 2.0 Application and Sizes a) The G.I. stranded wires covered in this Specification are intended for use on the overhead power line poles, distribution transformer structures etc. b) The G.I stranded wires shall be of 7/10SWG (7/3.15 mm for 11KV lines) and 7/14 SWG (7/2.5 mm for LT lines) standard sizes. 3.0 Materials The wires shall be drawn from steel made by the open hearth basic oxygen or electric furnace process and of such quality that when drawn to the size of wire specified and coated with zinc, the finished strand and the individual wires shall be of uniform quality and have the properties and characteristics as specified in this specification. The wires shall not contain sulphur and phosphorus exceeding 0.060% each. 3.1 Tensile Grade The wires shall be of tensile grade 4, having minimum tensile strength of 700 N/mm² conforming to 1S: General Requirements a) The outer wire of strands shall have a right-hand lay. b) The lay length of wire strands shall be 12 to 19 times the strand diameter. 24

25 3.3 Minimum Breaking Load & Galvanising The minimum breaking load of the wires before and after stranding shall be as follows: No. of Wires & Const. Wire Dia (mm Min. breaking load of the Single wire before stranding (KN) 7 (6/1) (6/1) (6/1) Min. breaking load of the standard wire (KN) Minimum weight of zinc coating before stranding Minimum weight of zinc coating before stranding 490 gm/mm2 490 gm/mm2 490 gm/mm2 475 gm/mm2 475 gm/mm2 475 gm/mm2 4.0 Construction a) The galvanized stay wire shall be of 7-wire construction. The wires shall be so stranded together that when an evenly distributed pull is applied at the ends of completed strand, each wire shall take an equal share of the pull. b) Joints are permitted in the individual wires during stranding but such joints shall not be less than 15 metres apart in the finished strands. c) The wire shall be circular and free from scale, irregularities, imperfection, flaws, splits and other defects. 5.0 Tolerances A tolerance of (+) 2.5% on the diameter of wires before stranding shall be permitted. 6.0 Sampling Criteria The sampling criteria shall be in accordance with IS : Tests on Wires before Manufacture 7.1 The wires shall be subjected to the following tests in accordance with IS :2141. a) Ductility Test b) Tolerance on Wire Diameter 7.2 Tests on Completed Strand The completed strand shall be tested for the following tests in accordance with IS:2141. a) Tensile and Elongation Test: The percentage elongation of the stranded wire shall not be less than 6%. b) Chemical analysis c) Galvanizing Test The Zinc Coating shall conform to "Heavy Coating" as laid down in 1S:

26 8.0 Marking Each coil shall carry a metallic tag, securely attached to the inner part of the coil bearing the following information: a) Manufacturers name or trade mark b) Lot number and coil number c) Size d) Construction e) Tensile Designation f) Lay g) Coating h) Length i) Mass j) ISI certification mark, if any 9.0 Packing The wires shall be supplied in Kg. coils. The packing should be done in accordance with the provisions of IS: Other Items: For remaining items of stay sets mentioned in the enclosed drawing, relevant applicable Indian standards shall be applicable. 26

27 GURANTEED TECHNICAL PARTICULARS STAY WIRE ( 7/10 & 7/14 SWG) Sl. GENERAL TECHNICAL PARTICULARS 7/10 SWG 7/14 SWG No 1 Nominal diameter of wire 2 Tolerance in diameter 3 Sectional Area (In Sq. mm.) 4 Tensile strength a Min. N/mm² b Max. N/mm² 5 Minimum breaking load (KN) 6 Type of coating Heavy/Medium/Light 7 Variety Hard/Soft 8 Weight of Zinc coating (Gms/Sq. Mtr.) Min. 9 No. of dips the coating is able to withstand as 18 ± 20ºC 10 Adhesion Test (Wrap Test at 1 turn per second coiling while stress not exceeding % nominal tensile strength) a Min. complete turn of wrap b Dia of mandrel on which wrapped 11 Bend Test a Angle b Dia round a format to be bent 12 Freedom from defect 13 Chemical composition the MS Wire used shall not exceed a Sulphur 0.060% b Phosphorous 0.065% SEAL & SIGNATURE OF THE TENDERER 27

28 1. SCOPE: TECHNICAL SPECIFICATION FOR 11 KV 45 KN / 70 KN DISC INSULATORS This specification covers the manufacture, testing and works supply and delivery of 11 KV Disc insulators. The Porcelain insulators shall conform to IS: ammended upto date. Insulators shall be of Ball & Socket type. 2. SERVICE CONDITIONS: The insulators to be supplied against this specification shall be suitable for satisfactory continuous operation under the following tropical conditions Maximum ambient temperature (Degree C) Minimum ambient temperature (Degree C) Relative Humidity (%) 10 to Maximum Annual Rainfall (mm) Maximum Wind pressure (kg/m.sq.) Maximum wind velocity (km/hour) Maximum altitude above mean sea level (meter) Isoceraunic level (days/year) Seismic level (Horizontal acceleration) 0.3 g Moderately hot and humid tropical climate conductive to rust and fungus growth 3. SYSTEM PARTICULARS: a) Nominal System Voltage 11 KV b) Corresponding highest system Voltage 12 KV c) Frequency 50 Hz with 3% tolerance d) Number of phase 3 e) Neutral earthing effectively grounded. f) Min. Impulse withstand voltage 75 KV 4. STANDARDS: Unless otherwise specified elsewhere in the specifications insulators shall confirm to the latest revisions of all relevant standards available at the time of placement of the order. The standards are as listed in annexure D. 28

29 5. GENERAL REQUIREMENTS : 5.1 The Porcelain insulators shall generally conform to IS: and any amendments up to date to the same. 5.2 Conductors : 5.3 Type The Disc Insulators will be used on lines on which the conductors will be A.A.A. Conductor of size up to 200 sq. mm. and ACSR of any size up to Panther (0.2 sq. inch copper equivalent). The insulators should withstand the conductor tension, the reversible wind load as well as the high frequency vibrations due to wind Insulator shall be suitable for both the suspension and strain type of load & shall be of ball and socket type. The insulators shall conform to Type B of IS: Diameter of porcelain disc insulator shall be 255mm except for 70KN Anti fog type Disc Insulators. Diameter of 70 KN Anti fog type Disc. Insulators shall be 280 mm. The center to center distance between ball & socket shall be 145mm Insulator Ends. Disc Insulators shall have `Ball and Socket ends. The security clips will have to be provided as per fig. 25 of I.S (Part-2) 1989 ( amended up to date) The colour of the units shall be brown for 45 KN Disc Insulators & Greenish for 70 KN Disc Insulators for identification The number of units to be used both on suspension and tension strings shall be as given below : Voltage Class Suspension Single Strings Double Tension Single Strings Double x2 3 3x x2 2 2x x2 1 1x Electromechanical & Mechanical Strength : The mechanical and electromechanical strength of the individual and the complete Disc shall be as specified below : The ball and socket will generally conform to IS: Part-II /1989. For ready reference major are reproduced below : Failing Load Pin Balls(mm) Socket(mm) 45 KN KN The accuracy and Alternative `B of these shall be checked with the corresponding `GO and `NO GO gauge. 29

30 5.5 Creepage Distances : The minimum creepage distance for each disc Insulator shall as mentioned below. Voltage Creepage Distance Creepage Distance 45 KN 70 KN Normal Anti fog Normal Anti fog 11 kv 230 mm 320 mm 320 mm 430 mm 5.6 Inter changeability : The insulator together with the ball and sockets fittings shall be of standard design suitable for use with the hardware of any other indigenous make conforming to relevant standards referred above. 6.0 TESTS: Suitable number of individual units and complete string shall be subject to the following tests in accordance with IS: 731/1971 with its latest amendments. 6.1 Type Tests: Following Type test shall be carried out on porcelain insulators as specified in IS: 731 / 1971 amended up to date. 1. Visual Examination. 2. Verification of dimensions. 3. Visible Discharge Test. 4. Impulse voltage withstand test. 5. Impulse voltage flashover test. 6. Wet one Minute Power Frequency withstand test and West Flashover test. 7. Temperature Cycle test. 8. Electromechanical failing load test. 9. Power frequency puncture withstand test. 10. Porosity test. 11. Galvanizing test. 6.3 Acceptance Tests: The test samples after having withstood the routine test shall be subject to the following acceptance tests in order indicated below: 1. Verification of dimensions. 2. Temperature Cycle test. 3. Twenty four hour mechanical test. 4. Electromechanical failing load test. 5. Power Frequency puncture withstand test. 6. Porosity test. 7. Galvanizing test. 6.4 Routine Tests : 1. Visual Examination. 2. Mechanical test. 3. Electrical test. 4. Twenty four hours mechanical test. 5. Electro mechanical failing load test. 30

31 7 TEST CERTIFICATE : The tenderer shall furnish detailed type test reports of the offered Disc Insulators as per clause 6.1 of the Technical Specifications at the NABL approved laboratories to prove that the Disc Insulators offered meet the requirements of the specification. These Type tests should have been carried out within five years prior to the date of opening of this tender. However, the tenderers who have supplied the Disc Insulators to M.S.E.D.C.L./ erstwhile M.S.E.B. against purchase order shall be exempted from submission of type test reports against this tender, provided. i) The offered Insulators are already fully type tested at Laboratories accredited by the National Accreditation Board of Testing and Calibration Laboratories (NABL) within five years prior to the date of opening of the tender. ii) There is no change in the design of type tested Disc Insulators and those offered against this tender. iii) Such tenderers complying (i) and (ii) above shall furnish an undertaking in the format scheduled F enclosed herewith. The detailed type test reports along with the certified drawings etc. or undertaking seeking exemption from their submission in the format schedule F, are to be submitted along with the offer. The purchaser reserve the right to demand repetition of some or all the Type Tests in presence of purchaser s representative at purchaser s cost. For this purpose, the tenderer shall quote unit rates for carrying out each Type Test. However, such unit rates will not be considered for evaluation of the offer. In case the unit fails in the type tests, the complete supply shall be rejected. The successful tenderer shall take approval/waiver of type tests from C.E. (Dist.), M.S.E.D.C.L. Prakashgad, Bandra, Mumbai, prior to commencement of supply. 8. TESTING FACILITIES : The tenderer must clearly indicate what testing facilities are available in the works of the manufacturer and whether facilities are adequate to carry out all Routine & acceptance Tests. These facilities should be available to Board's Engineers if deputed or carry out or witness the tests in the manufacturer works. If any test cannot be carried out at the manufacturer's work, the reasons should be clearly stated in the tender. The insulators shall be tested in accordance with the procedure detailed in IS-731/1971 amended up to date. 9. MATERIAL QUALITY AND WORKMANSHIP : The quality of porcelain and hardware in case of porcelain insulators and core & housing in case of polymeric insulators shall be of the highest grade and best workmanship such as is suitable and customary for extra high tension lines and shall conform to current IS or IEC (only in absence of the relevant I.S.S.). The porcelain shall be sound, free from defect, thoroughly vitrified and smoothly glazed and brown in colour. Unless otherwise specified the glaze shall cover all exposed porcelain parts of the insulator. Glazing shall be uniform and free from defects. Small and isolated defects in the insulator glaze of a total surface less than 0.5 sq.cm. will however be ignored. Deviation on this account may be supported by relevant IS. 31

32 10 MECHANICAL DESIGN : The design shall be such that stresses due to expansion and contraction in any part of insulator shall not lead to deterioration. Cement used in manufacture of the insulators shall not cause fracture due to expansion or loosening due to contraction. 11. DRAWINGS : The tender shall be accompanied with the detailed drawings showing the dimensions of the individual Disc, Ball & Socket, complete strings giving all the design dimensions of various component parts. The drawing for Insulators should clearly show the method of cementing the porcelain to the metal caps and balls. Generally it shall be as per IS. 12. RETEST AND REJECTION : 12.1 C-2.1 Sample Procedure for testing of insulators shall be as per Appendix C of IS- 731/1971 for Acceptance & Routine Tests. All the insulators selected at random according to col. 1 & 2 of Table 5 of IS- 731/1971 shall be subjected to dimensions and temperature cycle tests. The insulators failing to satisfy either of requirements shall be termed as defectives. The lot shall be considered as conforming to these requirements if the number of defectives found in the sample is less than or equal to corresponding acceptance number given in col. 4 of Table 5. The lot shall be rejected if the number of defectives in the same lot is greater than or equal to the first rejection number (r 1) given in col. 5. If the number of effectives is between the acceptance number and the first rejection number, a second sample of the same size (see col. 3 of Table 5) shall be selected from the lot at random and subjected to these tests. The number of defectives in the first sample and second sample shall be combined. If the combined number of defectives is less than the second rejection number (r2) given in col. 6 of Table 5, the lot shall be considered as confirming to these requirements. Otherwise the lot shall be rejected without further testing. C-2.2 The lot which has been found as confirming to the above requirements shall then be divided into two parts, as shown in col. 7 and 9 of Table 5. The number of insulators to be tested for mechanical, electromechanical and porosity tests shall be in accordance with col. 7 of Table 5. The lot shall be considered as confirming to these requirements if no defective is found in the sample and shall be rejected if there are two or more defectives. If there is one defective, a second sample of the same size (see col.8 of Table 5) shall be selected at random and subjected to the tests. The lot shall be considered as confirming to these requirements if no defective is found in the second sample; otherwise the lot shall be rejected without further testing. C-2.3 The lot which has been found as confirming to the above requirements of C- 2.1 shall then be tested for galvanizing test and puncture test. For this purpose, the sample size is given in col. 9 of Table 5. The lot shall be considered as confirming to these requirements if no defective is found in the sample and shall be rejected if two or more defectives are found in the sample. If there is one defective, a second sample of the same size (see col. 10 of Table 5) shall be selected at random and subjected to the tests. 32

33 The lot shall be considered as confirming to these requirements if no defective is found in the second sample; otherwise the lot shall be rejected without further testing. The lot shall be considered as conforming to the requirements of acceptance tests if conditions in C-2.1,C-2.2 and C-2.3 are satisfied. 13. MARKINGS : 13.1 Each insulator shall be legibly and indelibly marked to show the following : a) Name or trade mark of the manufacturer. b) Voltage & Type c) Month and year of manufacturing. d) Electromechanical strength in KN. e) MSEDCL marking The W clip shall be marked with/punched with the ball and socket sizes for which it is meant e.g.16b,20 etc Marking on porcelain shall be printed and shall be applied before firing. 14 PACKING : All insulators shall be packed in crates or boxes suitable for rough handling. Packing shall be marked with the strength and KV rating. 15 GUARANTEED TECHNICAL PARTICULARS : The tenderer shall furnish in the form attached (Schedule 'A') all the guaranteed technical particulars. 33

34 Name & Signature of Bidder with seal 34

35 GUARANTEED TECHNICAL PARTICULARS FOR 45 KN NORMAL TYPE DISC. INSULATOR UNIT. Sl. No Parameter Name Parameter type 1 Name of Manufacturer 2 Type of insulator 3 Material used for insulator housing 4 Colour of Disc Insulator ( Brown ) 5 Diameter of disc insulator in mm 6 Center to center distance between Ball & Socket in mm 7 Diameter of Ball & Socket is 16 mm (Y / N ) 8 Creepage distance minimum in mm. 9 Working voltage in kv. 10 Highest System Voltage in kv. 11 Impulse Withstand Voltage kv (Peak) 12 Impulse flashover voltage kv (Peak) (+ ve 1.2/50 wave) 13 Impulse flashover voltage kv (Peak) (- ve 1.2/50 wave) 14 Dry 1 min. power frequency withstand Voltage kv. 15 Wet 1 min. power frequency withstand Voltage kv. 16 Weight of single disc (kg) 17 No. of insulators per crate 18 Packed wt. of each crate (kg) Name & Signature of Bidder with seal 35

36 GUARANTEED TECHNICAL PARTICULARS FOR 45 KN ANTI FOG TYPE DISC. INSULATOR UNIT. Sl. No Parameter Name Parameter type 1 Name of Manufacturer 2 Type of insulator 3 Material used for insulator housing 4 Colour of Disc Insulator ( Brown ) 5 Diameter of disc insulator in mm 6 Center to center distance between Ball & Socket in mm 7 Diameter of Ball & Socket is 16 mm (Y / N ) 8 Creepage distance minimum in mm. 9 Working voltage in kv. 10 Highest System Voltage in kv. 11 Impulse Withstand Voltage kv (Peak) 12 Impulse flashover voltage kv (Peak) (+ ve 1.2/50 wave) 13 Impulse flashover voltage kv (Peak) (- ve 1.2/50 wave) 14 Dry 1 min. power frequency withstand Voltage kv. 15 Wet 1 min. power frequency withstand Voltage kv. 16 Weight of single disc (kg) 17 No. of insulators per crate 18 Packed wt. of each crate (kg) Name & Signature of Bidder with seal 36

37 GUARANTEED TECHNICAL PARTICULARS FOR 70 KN NORMAL TYPE DISC. INSULATOR UNIT. Sl. No Parameter Name Parameter type 1 Name of Manufacturer 2 Type of insulator 3 Material used for insulator housing 4 Colour of Disc Insulator ( Brown ) 5 Diameter of disc insulator in mm 6 Center to center distance between Ball & Socket in mm 7 Diameter of Ball & Socket is 16 mm (Y / N ) 8 Creepage distance minimum in mm. 9 Working voltage in kv. 10 Highest System Voltage in kv. 11 Impulse Withstand Voltage kv (Peak) 12 Impulse flashover voltage kv (Peak) (+ ve 1.2/50 wave) 13 Impulse flashover voltage kv (Peak) (- ve 1.2/50 wave) 14 Dry 1 min. power frequency withstand Voltage kv. 15 Wet 1 min. power frequency withstand Voltage kv. 16 Weight of single disc (kg) 17 No. of insulators per crate 18 Packed wt. of each crate (kg) Name & Signature of Bidder with seal 37

38 GUARANTEED TECHNICAL PARTICULARS FOR 70 KN ANTI FOG TYPE DISC. INSULATOR UNIT. Sl. No Parameter Name Parameter type 1 Name of Manufacturer 2 Type of insulator 3 Material used for insulator housing 4 Colour of Disc Insulator ( Brown ) 5 Diameter of disc insulator in mm 6 Center to center distance between Ball & Socket in mm 7 Diameter of Ball & Socket is 16 mm (Y / N ) 8 Creepage distance minimum in mm. 9 Working voltage in kv. 10 Highest System Voltage in kv. 11 Impulse Withstand Voltage kv (Peak) 12 Impulse flashover voltage kv (Peak) (+ ve 1.2/50 wave) 13 Impulse flashover voltage kv (Peak) (- ve 1.2/50 wave) 14 Dry 1 min. power frequency withstand Voltage kv. 15 Wet 1 min. power frequency withstand Voltage kv. 16 Weight of single disc (kg) 17 No. of insulators per crate 18 Packed wt. of each crate (kg) Name & Signature of Bidder with seal 38

39 TECHNICAL SPECIFICATION FOR 11/33 KV H.T. PIN INSULATORS 1. SCOPE: This specification covers the manufacture, testing and works supply and delivery of 11 kv & 33 kv Pin insulators. The Insulators shall be porcelain/composite type pin insulators. 1.1 Bidder must be an indigenous manufacturer and supplier of porcelain/composite type insulators of ratings 33 kv or above OR must have developed proven in house technology and manufacturing process for porcelain/composite type insulators of above rating OR possess technical collaboration/association with a manufacturer of porcelain type insulators of ratings 33 kv or above. The bidder shall furnish necessary evidence in support of the above along with the bid, which can be in the form of certification from the utilities concerned, or any other documents to the satisfaction of the purchaser. 2. SERVICE CONDITIONS: The insulators to be supplied against this specification shall be suitable for satisfactory continuous operation under the following tropical conditions Maximum ambient temperature (Degree C) Minimum ambient temperature (Degree C) Relative Humidity (%) 10 to Maximum Annual Rainfall (mm) Maximum Wind pressure (kg/m.sq.) Maximum wind velocity (km/hour) Maximum altitude above mean sea level (meter) Isoceraunic level (days/year) Seismic level (Horizontal acceleration) 0.3 g Moderately hot and humid tropical climate conductive to rust and fungus growth 3. SYSTEM PARTICULARS: a) Nominal System Voltage 11 kv, 33 kv b) Corresponding highest system Voltage 12 kv, 36 kv c) Frequency 50 Hz with 3% tolerance d) Number of phase e) Neutral earthing effectively grounded. f) Min. Impulse withstand voltage 75 kv, 170 kv 39

40 4. STANDARDS: Unless otherwise specified elsewhere in the specifications insulators shall confirm to IS: 731/1971/ IEC: / with the latest revisions at the time of placement of the order. The standards are listed in Annexure D. 5.0 GENERAL TECHNICAL REQUIREMENTS: The porcelain insulators shall generally conform to IS: 731/1971 and any amendments up to date to the same. The insulators shall confirm to type B of IS: 731/ Conductors: The pin insulators will be used on lines on which the conductors will be A.A.A. Conductor size up to 200 sq.mm. and ACSR of any size up to Panther (0.2 sq. inch copper equivalent). The insulators should withstand the conductor tension, the reversible wind load as well as the high frequency vibrations set up to due to wind. 5.2 Design Specification: The Porcelain Pin Insulators shall conform to the provisions of IS: or its latest version in all respects. The pin insulators shall be suitable for the spindle detailed below: Pin Insulator Suitable for head Shank dia Remarks 11 kv Small head as per Fig.I A of IS mm Lead thimbles Suitable pin (II)/1989 or latest heads shall be version. provided 33 kv Large head as per Fig.I B of IS-2486 (II)/1989 or latest version. 24mm Lead thimbles Suitable pin heads shall be provided For H. T. Pin Insulators, the top and neck of the Insulators should have dimensions as shown in the indicative Drg. No. CE (Dist)/MM-III/ Pin. Ins./1, which is enclosed herewith. 5.3 Strength : For pin insulators of 11 kv the minimum failing load shall be 5 kn and for 33 kv the minimum failing load shall be 10 kn. 40

41 5.4 Creepage Distance : The minimum creepage distance shall be those given below : Insulators Creepage distance kv Pin Insulator 320 mm 33 kv Pin Insulators 840 mm Material Quality and Workmanship The quality of porcelain/composite material and hardware and all workmanship should be of the highest grade and such as is suitable and customary for extra high tension lines and shall conform to current IS or IEC. (Only in absence of the relevant I.S.S.). The porcelain shall be sound, free from defect, thoroughly vitrified and smoothly glazed and brown in colour. Unless otherwise specified the glaze shall cover all exposed porcelain parts of the insulator. Glazing shall be uniform and free from defects. Small and isolated defects in the insulator glaze of a total surface less than 0.5 sq.cm. will however be ignored. Deviation on this account may be supported by relevant IS. 5.6 Mechanical Design: The design shall be such that stresses due to expansion and contraction in any part of insulator shall not lead to deterioration. Cement used in manufacture of insulator shall not cause fracture due to expansion or loosening due to contraction. 5.7 Design and construction for composite insulators Core The composite insulator shall have a core, housing & weathershed of insulating material and steel/aluminum hardware components for attaching it to the support/conductor. It shall be a glass-fiber reinforced epoxy resin rod of high strength (FRP rod). Glass fibers and resin shall be optimized in the FRP rod. Glass fibers shall be Boron free electrically corrosion resistant (ECR) glass fiber orboron free E-Glass and shall exhibit both high electrical integrity and high resistance to acid corrosion. The matrix of the FRP rod shall be Hydrolysis resistant. The FRP rod shall be manufactured through Pultrusion process. The FRP rod shall be void free. 41

42 5.7.2 Housing (Sheath) The FRP rod shall be covered by a seamless sheath of a silicone elastometric compound or silicone alloy compound of a thickness of 3 mm minimum. It should protect the FRP rod against environmental influences, external pollution and humidity. It shall be extruded or directly molded on the core and shall have chemical bonding with the FRP rod. The strength of the bond shall be greater than the tearing strength of the polymer. Sheath material in the bulk as well as in the sealing / bonding area shall be free from voids Weather sheds The composite polymer weather sheds made of silicone elastometic compound or silicon alloy shall be firmly bonded to the sheath, vulcanized to the sheath or molded as part of the sheath and shall be free from imperfections. The weather sheds should have silicon content of minimum 30% by weight. The strength of the weather sheds to sheath interface shall be greater than the tearing strength of the polymer. The interface, if any, between sheds and sheath (housing) shall be free from voids Metal End Fitting: End fitting transmit the mechanical load to the core. They shall be made of forged steel. G. I. pin shall be connected to the rod by means of a controlled compression technique. G. I. pins shall be of respective specified mechanical load and shall be hot dip galvanized after, all fittings have been completed. The material used in fittings shall be corrosion resistant. As the main duty of the end fittings is the transfer of mechanical loads to the core the fittings should be properly attached to the core by a coaxial or hexagonal compression process & should not damage the individual fibers or crack the core. The gap between fitting and sheath shall be sealed by a flexible silicone elastomeric compound or silicone alloy compound sealant. System of attachment of end fitting to the rod shall provide superior sealing performance between housing, i.e. seamless sheath and metal connection. The sealing must be moisture proof. The dimensions of end fittings of Insulators shall be in accordance with the standard dimensions stated in IEC: 60120/IS: Part-II / Corona and RI Performance All surfaces shall be clean, smooth, without cuts, abrasions or projections. No part shall be subjected to excessive localized pressure. The insulator and metal parts shall be so designed and manufactured that it shall avoid local corona formation and not generate any radio interference beyond specified limit under the operating conditions. 42

43 6.0 TESTS: 6.1 Testing Facilities: The tenderer must clearly indicate what testing facilities are available in the works of the manufacturer and whether facilities are adequate to carry out all Routine &acceptance Tests. If any test cannot be carried out at the manufacturer's work, the reasons should be clearly stated in the tender. The insulators shall be tested in accordance with the procedure detailed in IS-731/1971 or IEC / with latest amendments. 6.2 Design Tests: For composite insulators it is essential to carry out design test as per clause 4.1 of IEC / with latest amendments. The design tests are intended to verify the suitability of the design, materials and method of manufacture (technology). When a composite insulator is submitted to the design tests, the result shall be considered valid for the whole class of insulators, which are represented by the one tested and having the following characteristics: Same materials for the core, and sheds and same manufacturing method; Same material of the fittings, the same design, the same method of attachment; Same or greater layer thickness of the shed material over the core (including a sheath where used); Same or smaller ratio of the highest system voltage to insulation length; Same or smaller ratio of all mechanical loads to the smallest core diameter between fittings Same or greater diameter of the core. The tested composite insulators shall be identified by a drawing giving all the dimensions with the manufacturing tolerances. Manufacturer should submit test reports for Design Tests as per IEC (clause 5) along with the bid. Additionally following tests shall be carried out or reports for the tests shall be submitted after award of contract: UV test: the test shall be carried out in line with clause 7.2 of ANSI C

44 6.3 Type Test : The type tests mentioned below should be carried out on porcelain type of Insulator offered by the tenderer and the test shall conform to requirements as per Table IA & as per clause of IS 731/1971 (latest version). 1. Visual Examination. 2. Verification of dimensions. 3. Visible Discharge Test 4. Impulse Voltage Withstand Test. 5 Wet Power Frequency Voltage Withstand Test 6. Temperature Cycle Test. 7. Electro-Mechanical failing load test. 8. Power frequency puncture withstand test. 9. Porosity test. Following Type test shall be conducted on a suitable number of composite insulator as per: IEC The bidder shall submit type test reports as per IEC along with the bid. Additional type tests required if any shall be carried out by the manufacturer, after award of contract for which no additional charges shall be payable. In case, the tests have already been carried out, the manufacturer shall submit reports for the same. 44

45 6.3.2 Acceptance Tests The Test samples after having withstood the routine test, porcelain type insulators shall be subject to the following acceptance tests in order indicted below as per clause of IS-731/ Verification of dimensions. 2. Temperature Cycle Test. 3. Porosity Test. The test samples after having withstood the routine test, composite insulators shall be subject to the following acceptance tests in order indicated below: Routine Test : Routine test shall be made on every porcelain insulators as specified in clause of IS- 731/1971 or latest version. However for the guidance of the tenderer the routine tests are mentioned below : 1) Visual Examination. 2) Electrical Routine Test. Routine test shall be made on every composite insulators as specified in IEC Every composite insulator shall withstand mechanical routine test at ambient temperature tensile load at RTL corresponding to at least 50 % of the SML for at least 10 sec. 7.0 TEST CERTIFICATE: The tenderer shall furnish detailed type test reports of the offered porcelain/ composite Insulators as per clause of the Technical Specifications at the NABL approved laboratories to prove that the Insulators offered meet the requirements of the specification. These Type tests should have been carried out within five years prior to the date of opening of this tender. i) The offered Insulators are already fully type tested at Laboratories accredited by the National Accreditation Board of Testing and Calibration Laboratories (NABL) within five years prior to the date of opening of the tender. 45

46 ii) (iii) There is no change in the design of type-tested porcelain/composite Insulators and those offers against this tender. Such tenderers complying (i) and (ii) above shall furnish an undertaking in the format scheduled F enclosed herewith. The detailed Type tests along with the relevant certified drawings etc. or undertaking in the format schedule F seeking exemption from their submission of the type test reports are to be submitted along with the offer. The purchaser reserves right to demand repetition of some or all the Type Test in presence of purchaser s representative at purchaser s cost. For this purpose, the tenderer shall quote unit rates for carrying out each Type Test. However, such unit rates will not be considered for evaluation of the offer. In case the unit fails in the Type Tests, the complete supply shall be rejected. 8.0 DRAWINGS: The tender shall be accompanied with the detailed drawings with dimensions for each ratings of pin insulators i.e.11 & 33 KV. The Bidder shall furnish full description and illustration of the material offered.8.1 The Bidder shall furnish along with the bid the outline drawing (3 copies) of each insulator unit including a cross sectional view of the long rod insulator unit. The drawing shall include but not be limited to the following information: (a) Minimum Creepage distance with positive tolerance (b) Protected creepage distance (c) Unit mechanical and electrical characteristics (d) Size and weight of ball and socket/tongue & clevis (e) Weight of composite long rod units (f) Materials (i) Identification mark (ii) Manufacturer s catalogue number 9. Retest and Rejection: 9.1 C-2.1 Sample Procedure for testing of porcelain insulators shall be as per Appendix C of IS- 731/1971 for Acceptance & Routine Tests. All the insulators selected at random according to col. 1 & 2 of Table 5 of IS-731/1971 shall be subjected to dimensions and temperature cycle tests. The insulators failing to satisfy either of requirements shall be termed as defectives. The lot shall be considered as confirming to these requirements if the number of defectives found in the sample is less than or equal to corresponding acceptance number given in col. 4 of Table 5. The lot shall be rejected if the number of defectives in the same lot is greater than or equal to the first rejection number (r1) given in col. 5. If the number of defectives is between the acceptance number and the first rejection number, a second sample of the same size (see col. 3 of Table 5) shall be selected from the lot at random and subjected to these tests. The number of defectives in the first sample and second sample shall be combined. If the combined number of defectives is less than the second rejection number (r2) given in col. 6 of Table 5, the lot shall be considered 46

47 as confirming to these requirements. Otherwise the lot shall be rejected without further testing. C-2.2 The lot which has been found as confirming to the above requirements shall then be divided into two parts, as shown in col 7 and 9 of Table 5. The number of insulators to be tested for mechanical, electromechanical and porosity tests shall be in accordance with col 7 of Table 5. The lot shall be considered as confirming to these requirements if no defective is found in the sample and shall be rejected if there are two or more defectives. If there is one defective, a second sample of the same size(see col 8 of Table 5) shall be selected at random and subjected to the tests. The lot shall be considered as confirming to these requirements if no defective is found in the second sample; otherwise the lot shall be rejected without further testing. C-2.3 The lot which has been found as confirming to the above requirements of C- 2.1 shall then be tested for galvanizing test and puncture test. For this purpose, the sample size is given in col. 9 of Table 5. The lot shall be considered as confirming to these requirements if no defective is found in the sample and shall be rejected if two or more defectives are found in the sample. If there is one defective, a second sample of the same size (see col. 10 of Table 5) shall be selected at random and subjected to the tests. The lot shall be considered as confirming to these requirements if no defective is found in the second sample; otherwise the lot shall be rejected without further testing. The lot shall be considered as conforming to the requirements of acceptance tests if conditions in C-2.1, C-2.2 and C-2.3 are satisfied. 9.2 Sample Procedure for testing of composite insulators shall be as per clause 7.1 to 7.6 of IEC for Acceptance & Routine Tests. For the sampling tests, two samples are used, E1and E2. The sizes of these samples are indicated in the table below. If more than insulators are concerned, they shall be divided into an optimum number of lots comprising between 2000 and insulators. The results of the tests shall be evaluated separately for each lot. The purchaser s representative shall select the composite insulators from the lot at random. The samples shall be subjected to the applicable sampling tests. The sampling tests are: Verification of dimensions - (E1 + E2) Verification of the locking system - (E2) Verification of tightness of the interface between - (E2) end fittings & Insulator housing 47

48 Verification of the specified mechanical load SML - (E1) Galvanizing test - (E2) In the event of a failure of the sample to satisfy a test, the retesting procedure for composite insulators shall be as per IEC Standard.: Markings: Each insulator shall be legibly and indelibly marked to show the following: a) Name or trademark of the manufacturer. b) Highest system Voltage c) Month and year of manufacturing. d) Min. failing load in KN. e) Tender Reference Number 10.2 Marking on porcelain shall be printed and applied before firing. 11. Packing : All insulators shall be packed in crates or boxes suitable for rough handling. Packing shall be marked with the strength and KV rating. 12. Guaranteed Technical Particulars : The tenderer shall furnish in the attached form (Schedule 'A') all the guaranteed technical particulars. 48

49 GUARANTEED TECHNICAL PARTICULARS FOR 11KV PIN INSULATOR Sl.No. Parameter Name Parameter type 11 KV 1 Name of Manufacturer. 2 Type of insulator 3 Standard according to which the insulators manufactured & tested. 4 Name of material used in manufacture of the insulator with class / grade. 4(a) Material of housing & weather sheds (Silicon content by weight). 5 Diameter of first outer shell 6 Diameter of second middle shell 7 Diameter of third lower shell in mm (min.) 8 Height of Insulator in mm 9 Minimum failing load in KN (5) 10 Min. creepage distance in mm. (320) 11 Suitable for shank diameter in mm (20) 12 Net weight of single Pin. Ins. 13 Nominal System Voltage in kv. 14 Highest System Voltage in kv (rms).(12) 15 Dry 1 min. power frequency withstand Voltage kv (rms) 16 Wet 1 min. power frequency withstands Voltage. KV (rms) 17 Dry flashover voltage. kv (rms) 18 Wet flashover voltage. KV (rms) 19 Dry lighting Impulse Withstand Voltage (Positive) kv (Peak) 20 Dry lighting Impulse Withstand Voltage test (Negative) kv (Peak) 21 Dry lighting Impulse flashover Voltage (Positive) kv (Peak) 22 Dry lighting Impulse flashover Voltage test (Negative)kV (Peak) 23 Method of fixing of sheds to housing (Specify):Single mould or Modular construction (Injection molding/compression molding) 24 Any other particulars which the bidder may like to give 25 Type test reports as per specification are submitted 26 Type test reports SEAL & SIGNATURE OF THE TENDERER 49

50 GUARANTEED TECHNICAL PARTICULARS FOR 33 KV PIN INSULATOR Sl.No. Parameter Name Parameter type 33 KV 1 Name of Manufacturer. 2 Type of insulator 3 Standard according to which the insulators manufactured & tested. 4 Name of material used in manufacture of the insulator with class / grade. 4(a) Material of housing & weather sheds (Silicon content by weight). 5 Diameter of first outer shell 6 Diameter of second middle shell 7 Diameter of third lower shell in mm (min.) 8 Height of Insulator in mm 9 Minimum failing load in KN (10) 10 Min. creepage distance in mm. (900) 11 Suitable for shank diameter in mm (24) 12 Net weight of single Pin. Ins. 13 Nominal System Voltage in kv. 14 Highest System Voltage in kv (rms).(36) 15 Dry 1 min. power frequency withstand Voltage kv (rms) 16 Wet 1 min. power frequency withstands Voltage. KV (rms) 17 Dry flashover voltage. kv (rms) 18 Wet flashover voltage. KV (rms) 19 Dry lighting Impulse Withstand Voltage (Positive) kv (Peak) 20 Dry lighting Impulse Withstand Voltage test (Negative) kv (Peak) 21 Dry lighting Impulse flashover Voltage (Positive) kv (Peak) 22 Dry lighting Impulse flashover Voltage test (Negative)kV (Peak) 23 Method of fixing of sheds to housing (Specify):Single mould or Modular construction (Injection molding/compression molding) 24 Any other particulars which the bidder may like to give 25 Type test reports as per specification are submitted 26 Type test reports SEAL & SIGNATURE OF THE TENDERER 50

51 TECHNICAL SPECIFICATION FOR LT SHACKLE INSULATORS 1. SCOPE: The specification provides for manufacture, testing before dispatch, supply and delivery of LT Shackle Insulators as per the particulars given in "Schedule of Requirements" attached. 2. STANDARDS: The LT Shackle Insulators shall conform to IS:1445/1977 (the latest i thereof) and shall be brown glazed. The tenders shall go through the above thoroughly before making their offer. The material shall be for us moderately hot and humid tropical climate, conducive to rust and fun growth. 3. GENERAL REQUIREMENT: i) The porcelain shall be sound, free from defects thoroughly vitrify and smoothly glazed. ii) The design of Insulator should be such that, stresses due to expans or and contraction in any part of the insulator shall not lead to deterioration. iii) The glaze shall be Brown in colour except for the screw threads the top portion on which the conductor is supported during fir which may be left unglazed, all other surfaces of the insulator shall effectively, glazed. 4. TESTS : The Insulator shall comply with the following routine, type and accepta tests as per IS:1445/1977 (the latest issue thereof) Routine Test : Visual Examination 4.2 Type Test : The firm shall submit the type test report shall be from any NABL accredit laboratory not more than 5 years old along with offer.the following type te are to be carried out on sample in the order mentioned bellow as per 5300/69. a) Visual examination. b) Verification of dimensions. c) Dry one minute power frequency withstand test. d) Wet one minute power frequency withstand test. e) Temperature Cycle test. f) Mechanical strength test g) Porosity test. h) Power frequency puncture withstand test 51

52 NOTE : The identification marks of firm provided on the insulator should be invariably mentioned in the type test certificate. 4.3 Acceptance Tests : (to be conducted in the following order) a) Visual examination. b) Verification of dimensions. c) Temperature Cycle test. d) Mechanical strength test. e) Porosity test (Applicable only to HT Guy Insulator Type-C). 5. MARKING: The Insulators shall be legibly and indelibly marked as shown below. a) Name and trade-mark of the manufacturer. b) Month and year of manufacture and. c) AP PDCL (Name of the purchaser) Markings on porcelain shall be printed and shall be applied before firing. 6. TYPE AND DIMENSIONS: The dimensions shall be of size 90X75 mm and construction of the LT Shackle Insulators should be as per IS 1445/1977 and shall be brown glazed. 7. TEST AND TEST CERTIFICATES: The test shall be carried out as per the IS before dispatch and the test certificates shall be furnished for approval. Copies of type test certificates of identical materials for each type with dimensional drawings shall invariably accompany the tender. The type tests as specified in the IS should be carried out not later than 5 years from the date of opening of bid. 8. PACKING : This shall be done in wooden crates suitable for rough handling. 9. SAMPLES : Two Nos. samples of LT Shackle Insulators shall invariably accompany the tender. Tenders for which samples are not received by the stipulated date will be rejected. 10. GUARANTEED TECHNICAL PARTICULARS : The technical particulars as specified in the IS shall be guaranteed and a statement of guaranteed particulars shall be furnished along with the tender. 52

53 SEAL & SIGNATURE OF THE TENDERER 53

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57 TECHNICAL SPECIFICATION OF LT PIN INSULATOR 1. SCOPE : The specification covers the manufacture, testing at works supply and delivery of Porcelain insulators for overhead power lines with a nominal voltage below 1000 volts. Both LT Pin insulator (105x80)mm & (100x75)mm are covered. 2. APPLICABLE STANDARDS: Except when they conflict with the specific requirements of this specification, the insulators shall comply with IS : 1445/1977 or the latest version thereof. 3. GENERAL REQUIREMENTS: The porcelain shall be sound, free from defects, thoroughly vitrified and smoothly glazed. The design of the insulators shall be such that the stresses due to expansion and contraction in any part of the insulator shall not lead to its deterioration. The glaze shall be brown in color for insulators. The glaze shall cover the entire porcelain surface parts except those areas that serve as supports during firing. The insulators shall be suitable for use with all Aluminium Conductor or Copper conductor or ACSR upto 100 sq.mm. The insulators should withstand the conductor tension the reversible wind load as well as the high frequency vibrations set due to wind. 4. SYSTEM CONDITIONS: Frequency : 50 Hz Nominal System Voltage : 400/230 V Maximum System Voltage LT System : 440/250 V Minimum LT Voltage : 370 V Power frequency one minute withstand Voltage(wet) : 10 KV Neutral Earthing arrangement LT System : Solidly Earthed 5. TESTS: a. Type tests: a) Visual examination b) Verification of dimensions c) Temperature cycle test d) Dry one minute power frequency withstand test e) Wet one minute power frequency withstand test 57

58 f) Mechanical strength test g) Porosity test 5.2 Acceptance test: The insulators, after having withstood the routine test shall be subjected to the following acceptance tests in the order given below: a) Verification of Dimensions. b) Temperature cycle test c) Mechanical strength test d) Porosity test 5.3 Routine tests: ii) Visual examination 6. TESTING FACILITIES: a. The Bidder must clearly indicate what testing facilities are avail able in the works of the manufacturer and whether the facilities, are adequate to carr y out all the routine as well as type tests. These facilities should be made available to Purchaser,s Engineers if deputed to carry out or witness the tests. I f any tests cannot be carried out at the manufacturer s works, the reasons should be clearly stated in the tender. b. The Bidder shall furnish detailed t y pe test reports of the offered LT Pin insulator as per clause 5.1 of this specification. All the above Type Tests shall be carried out at laboratories, which are accredited, by the National Accreditation Board of Testing and Calibration Laboratories (NABL) of Government of India to prove that the insulators offered meet the requirements of the specification. These Type Tests should have been carried out within five years prior to the date of opening of this tender. c. There offered L.T. pin insulators are already fully Type Tested at Laboratories accredited by the National Accreditation Board of Testing and Calibration Laboratories (NABL) within five years prior to the date of opening of the tender. 7. Drawings : The tender shall be accompanied with the detailed drawings showing the dimensions of the individual insulator, giving all the design dimensions of various component parts. Generally it shall be as per IS. 8. MARKING: a. Each insulator shall be legibly and indelibly marked to show the following: i) Name of Purchaser- NESCO ii)name or trade mark of the manufacturer 58

59 iii) Year of manufacturer iv) ISI certificate, mark, if any. b. Marking on porcelain shall be applied before firing. 9. Packing : All insulators shall be packed in crates or boxes suitable for rough handling. Packing shall be marked with the strength and voltage rating. SEAL & SIGNATURE OF THE TENDERER 59

60 NB- Every insulator should bear the marking of manufacturer s name and ISI mark Name & Signature of Bidder with seal 60

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66 TECIINICAL SPECIFICATION OF G.I. PIN FOR L.T. PIN INSULATOR I. SCOPE: This specification covers design manufacture testing, supply and delivery of the porcelain insulators, fittings to be used on 415/240 volts overhead power lines within the state of Assam. II. STANDARD: The L.T. Pin shall be as per REC 8pecification no. 14/1972 and shall be suitable for use in L.T. Pin Insulator conforming to 188:1445/1966. III. GENERAL REQUIREMENT: The Pins shall be as single piece obtained by process of forging. They shall be of good finish, free from flaws and other defects. The finish of the collar shall be such that a sharp angle between the collar and the shank is avoided. All ferrous pins, nuts and washers shall be galvanized and small fittings like spring washes, nuts etc. may he with zinc. The threads of nuts & lapped holes shall be electroplated/cut after galvanizing and shall be well oiled or greased. The edges on the outside of fittings such as at the holes etc. shall be rounded. The galvanizing should be as per ISS: 2633/l964. The dimensions of the pins shall be as follows: - (a) Stalk length mm. (b) Shank length mm. (c) Thickness of collar - 5 mm. (d) Dia of collar - 32 mm. (e) Dia of shank - 16 mm. (f) Threaded length of shank - 75 mm. (g) Dia of the shank head - 16 mm. (h) Threaded length of stalk - 32 ± 3 mm. The pins shall have minimum failing load of 2 KN. IV. PACKING: For packing of insulator pins, double gunny bags or wooden cases if deemed necessary, shall be employed. The gross weight of the packing shall not normally exceed 50 Kg. The gunny bags of wooden case shall contain an identification mark and should be strong enough to withstand rough handling during transit. 66

67 V. TESTS: LT. Pin shall comply with the following test Type test a) Visual Examination test. b) Verification of dimensions c) Checking of threads. d) Galvanizing tests. e) Mechanical strength test. VI. Routine Test: (a) Visual Examination Test. VII. Acceptance Test: (a) (b) Checking of threads on heads. Galvanizing test. VIII. Sample: The Tenderer shall submit the sample complete with accessories at his own cost along with the technical Bid. Samples not received within the stipulated time may disqualify the tender. The tender without sample shall be rejected outright. Tenderer whose samples have been approved earlier in this office need not furnish the same. IX. INSPECTION: All tests and inspection shall be carried out at the works of the manufacturer unless otherwise agreed by the purchaser and the manufacturer at the time of purchase. A manufacturer shall afford the inspector representing the purchaser, all reasonable facilities without charge to satisfy that the materials are being purchased as per specification. The purchaser reserves the right to have the test carried out at his cost by independent agency, whenever there is dispute regarding the quality of the materials supplied. 67

68 X. GUARANTEED TECHNICAL PARTICULARS: (To be filled in by the tenderer) 1. Name and address of the manufacturer. 2. Trade mark of the manufacturer. 3. Physical dimensions. (a) Stalk length in mm. (c) Thickness of collar in mm. (e) Threaded length of shank in mm. (g) Dia of stalk head in mm. (b) Shank length in mm (d) Diameter of shank in mm. (f) Diameter of shank in mm. (h) Threaded length of stalk in mm. 4. Gross weight in KG. 5. Weight of zinc coating in gms. 6. Mechanical failing load. 7. Other particulars if any. 11 DRAWING: Drawing specifically showing all dimensions is to be submitted along with technical bid. SEAL & SIGNATURE OF THE TENDERER 68

69 TECIINICAL SPECIFICATION OF G.I. PIN FOR 33 KV PIN INSULATOR 1. SCOPE: This specification covers design manufacture testing, supply and delivery of the porcelain insulators, fittings to be used on 415/240 volts overhead power lines within the state of Assam. 2. STANDARD: The L.T. Pin shall be as per REC 8pecification no. 14/1972 and shall be suitable for use in L.T. Pin Insulator conforming to 188:1445/ GENERAL REQUIREMENT: The Pins shall be as single piece obtained by process of forging. They shall be of good finish, free from flaws and other defects. The finish of the collar shall be such that a sharp angle between the collar and the shank is avoided. All ferrous pins, nuts and washers shall be galvanized and small fittings like spring washes, nuts etc. may he with zinc. The threads of nuts & lapped holes shall be electroplated/cut after galvanizing and shall be well oiled or greased. The edges on the outside of fittings such as at the holes etc. shall be rounded. The galvanizing should be as per ISS: 2633/l964. The dimensions of the pins shall be as follows: - (a) Stalk length mm. (b) Shank length mm. (c) Thickness of collar - 6 mm. (d) Dia of collar - 50 mm. (e) Dia of shank - 24 mm. (f) Threaded length of shank mm. (g) Dia of the shank head mm. (h) Threaded length of stalk - 47 mm. The pins shall have minimum failing load of 10 KN. 4. PACKING: For packing of insulator pins, double gunny bags or wooden cases if deemed necessary, shall be employed. The gross weight of the packing shall not normally exceed 50 Kg. The gunny bags of wooden case shall contain an identification mark and should be strong enough to withstand rough handling during transit. 5. TESTS: LT. Pin shall comply with the following test Type test a. Visual Examination test. b) Verification of dimensions d) Checking of threads. d) Galvanizing tests. 69

70 f) Mechanical strength test. 6. Routine Test: (a) Visual Examination Test. 7. Acceptance Test: (a) (b) Checking of threads on heads. Galvanizing test. 8. Sample: The Tenderer shall submit the sample complete with accessories at his own cost along with the technical Bid. Samples not received within the stipulated time may disqualify the tender. The tender without sample shall be rejected outright. Tenderer whose samples have been approved earlier in this office need not furnish the same. 9. INSPECTION: All tests and inspection shall be carried out at the works of the manufacturer unless otherwise agreed by the purchaser and the manufacturer at the time of purchase. A manufacturer shall afford the inspector representing the purchaser, all reasonable facilities without charge to satisfy that the materials are being purchased as per specification. The purchaser reserves the right to have the test carried out at his cost by independent agency, whenever there is dispute regarding the quality of the materials supplied. 10. GUARANTEED TECHNICAL PARTICULARS: (To be filled in by the tenderer) 8. Name and address of the manufacturer. 9. Trade mark of the manufacturer. 10. Physical dimensions. (a) Stalk length in mm. (b) Shank length in mm (c) Thickness of collar in mm. (e) Threaded length of shank in mm. (g) Dia of stalk head in mm. (d) Diameter of shank in mm. (f) Diameter of shank in mm. (h) Threaded length of stalk in mm. 11. Gross weight in KG. 12. Weight of zinc coating in gms. 13. Mechanical failing load. 14. Other particulars if any. 11 DRAWING: Drawing specifically showing all dimensions is to be submitted along with technical bid. SEAL & SIGNATURE OF THE TENDERER 70

71 TECHNICAL SPECIFICATION OF G.I. PIN FOR 11 KV PIN INSULATOR 1. SCOPE: This specification covers design manufacture testing, supply and delivery of the porcelain insulators, fittings to be used on 415/240 volts overhead power lines within the state of Assam. 2. STANDARD: The L.T. Pin shall be as per REC 8pecification no. 14/1972 and shall be suitable for use in L.T. Pin Insulator conforming to 188:1445/ GENERAL REQUIREMENT: The Pins shall be as single piece obtained by process of forging. They shall be of good finish, free from flaws and other defects. The finish of the collar shall be such that a sharp angle between the collar and the shank is avoided. All ferrous pins, nuts and washers shall be galvanized and small fittings like spring washes, nuts etc. may he with zinc. The threads of nuts & lapped holes shall be electroplated/cut after galvanizing and shall be well oiled or greased. The edges on the outside of fittings such as at the holes etc. shall be rounded. The galvanizing should be as per ISS: 2633/l964. The dimensions of the pins shall be as follows: - (a) Stalk length mm. (b) Shank length mm. (c) Thickness of collar - 5 mm. (d) Dia of collar - 40 mm. (e) Dia of shank - 24 mm. (f) Threaded length of shank mm. (g) Dia of the shank head mm. (h) Threaded length of stalk - 44 mm. The pins shall have minimum failing load of 5 KN. 5. PACKING: For packing of insulator pins, double gunny bags or wooden cases if deemed necessary, shall be employed. The gross weight of the packing shall not normally exceed 50 Kg. The gunny bags of wooden case shall contain an identification mark and should be strong enough to withstand rough handling during transit. 6. TESTS: LT. Pin shall comply with the following test Type test 71

72 a. Visual Examination test. b) Verification of dimensions e) Checking of threads. d) Galvanizing tests. g) Mechanical strength test. 7. Routine Test: (a) Visual Examination Test. 8. Acceptance Test: (a) (b) Checking of threads on heads. Galvanizing test. 9. Sample: The Tenderer shall submit the sample complete with accessories at his own cost along with the technical Bid. Samples not received within the stipulated time may disqualify the tender. The tender without sample shall be rejected outright. Tenderer whose samples have been approved earlier in this office need not furnish the same. 10. INSPECTION: All tests and inspection shall be carried out at the works of the manufacturer unless otherwise agreed by the purchaser and the manufacturer at the time of purchase. A manufacturer shall afford the inspector representing the purchaser, all reasonable facilities without charge to satisfy that the materials are being purchased as per specification. The purchaser reserves the right to have the test carried out at his cost by independent agency, whenever there is dispute regarding the quality of the materials supplied. 11. GUARANTEED TECHNICAL PARTICULARS: (To be filled in by the tenderer) 1 Name and address of the manufacturer. 2 Trade mark of the manufacturer. 3 Physical dimensions. (a) Stalk length in mm. (b) Shank length in mm (c) Thickness of collar in mm. (e) Threaded length of shank in mm. (g) Dia of stalk head in mm. (d) Diameter of shank in mm. (f) Diameter of shank in mm. (h) Threaded length of stalk in mm. 4 Gross weight in KG. 5 Weight of zinc coating in gms. 6 Mechanical failing load. 7 Other particulars if any. 12. DRAWING: Drawing specifically showing all dimensions is to be submitted along with technical bid. SEAL & SIGNATURE OF THE TENDERER 72

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101 TECHNICAL SPECIFICATIONS 33 KV V CROSS ARM, BACK CLAMP FOR V CROSS ARM & POLE TOP BRACKET 1.0 Cross arms and Pole Top Brackets for 33 kv construction at intermediate and light angle pole shall be fabricated from grade 43A mild steel of channel section and for heavy angle poles, end poles and section poles fabricated from grade 43A mild steel of angle section. The grades of structural steel shall conform to IS 226: The V Cross arm shall be made out of 100 x 50 x 6.4 mm MS Channel as per REC Standard M-1. Weight of channel is 7.9 kg/mtr. The Back Clamp shall be made out of 50 x 8 MS Flat as per REC Standard & shall be suitably designed to fit PSC Pole 9 Mtr x 300 Kg / 8 Mtr x 200 Kg. The Pole Top Bracket shall be made out of 65 x 65 x 6 mm MS Angle & 100x 50x 6.4 M.S.Channel welded together as per REC Standard M-4, suitably designed to fit PSC Pole 9 Mtr x 300 Kg / 8 Mtr x 200 Kg./ 11 Mtr x 300 Kg 3.0 Except where otherwise indicated all dimensions are subject to the following tolerances: a) dimensions up to and including 50mm:+1mm: and b) dimensions greater than 50mm: +2% All steel members and other parts of fabricated material as delivered shall be free of warps, local deformation, unauthorized splices, or unauthorized bends. Bending of flat strap shall be carried out cold. Straightening shall be carried out by pressure and not by hammering. Straightness is of particular importance if the alignment of bolt holes along a member is referred to its edges. Holes and other provisions for field assembly shall be properly marked and cross referenced. Where required, either by notations on the drawing or by the necessity of proper identification and fittings for field assembly, the connection shall be match marked. A tolerance of not more than 1mm shall be permitted in the distance between the center lines of bolt holes. The holes may be either drilled or punched and, unless otherwise stated, shall be not more than 2mm greater in diameter than the bolts. When assembling the components force may be used to bring the bolt holes together (provided neither members nor holes are thereby distorted) but all force must be removed before the bolt is inserted. Otherwise strain shall be deemed to be present and the structure may be rejected even though it may be, in all other respects, in conformity with the specification. The back of the inner angle irons of lap joints shall be chamfered and the ends of the members cut where necessary and such other measures taken as will ensure that all members can be bolted together without strain or distortion. In particular, steps shall be taken to relieve stress in cold worked steel so as to prevent the onset of embrittlement during galvanizing. Similar parts shall be interchangeable. 101

102 Shapes and plates shall be fabricated and assembled in the shop to the greatest extent practice able. Shearing flame cutting and chipping shall be done carefully, neatly and accurately. Holes shall be cut, drilled or punched at right angles to the surface and shall not be made or enlarged by burning. Holes shall be clean-cut without torn or ragged edges, and burrs resulting from drilling or reaming operations shall be removed with the proper tool. Shapes and plates shall be fabricated to the tolerance that will permit field erection within tolerance, except as otherwise specified. All fabrication shall be carried out in a neat and workmanlike manner so as to facilitate cleaning, painting, galvanizing and inspection and to avoid areas in which water and other matter can lodge. Contact surfaces at all connections shall befree of loose scale, dirt, burrs, oil and other foreign materials that might prevent solid seating of the parts. 4.0 GALVANISING For use in construction at coastal areas it shall be required for galvanizing the Cross arms and Pole top brackets as following : All galvanizing shall be carried out by the hot dip process, in accordance with Specification IS However, high tensile steel nuts, bolts and spring washer shall be electro galvanized to Service Condition 4. The zinc coating shall be mooth, continuous and uniform. It shall be free from acid spot and shall not scale, blister or be removable by handling or packing. There shall be no impurities in the zinc or additives to the galvanic bath which could have a detrimental effect on the durability of the zinc coating. Before picking, all welding, drilling, cutting, grinding and other finishing operations must be completed and all grease, paints, varnish, oil, welding slag and other foreign matter completely removed. All protuberances which would affect the life of galvanizing shall also be removed. The weight of zinc deposited shall be in accordance with that stated in Standard IS 2629 and shall not less than 0.61kg/m² with a minimum thickness of 86 microns for items of thickness more than 5mm, 0.46kg/m² (64 microns) for items of thickness between 2mm and 5mm and 0.33kg/m² (47 microns) for items less than 2mm thick. Parts shall not be galvanized if their shapes are such that the pickling solutions cannot be removed with certainty or if galvanizing would be unsatisfactory or if their mechanical strength would be reduced. Surfaces in contact with oil shall not be galvanized unless they are subsequently coated with an oil resistant varnish or paint. In the event of damage to the galvanizing the method used for repair shall be subject to the approval of the Project Manager or that of his representative. Repair of galvanizing on site will generally not be permitted. The threads of all galvanized bolts and screwed rods shall be cleared of spelter by spinning or brushing. A die shall not be used for cleaning the threads unless 102

103 specifically approved by the Project Manager. All nuts shall be galvanized. The threads of nuts shall be cleaned with a tap and the threads oiled. Partial immersion of the work shall not be permitted and the galvanizing tank must therefore be sufficiently large to permit galvanizing to be carried out by one immersion. After galvanizing no drilling or welding shall be performed on the galvanized parts of the equipment excepting that nuts may be threaded after galvanizing. To avoid the formation of white rust galvanized materials shall be stacked during transport and stored in such a manner as to permit adequate ventilation. Sodium dichromate treatment shall be provided to avoid formation of white rust after hot dip galvanization. The galvanized steel shall be subjected to test as per IS

104 SEAL & SIGNATURE OF THE TENDERER 104