GETCO/E/TS - 4XMER02/R0 Mar12 GUJARAT ENERGY TRANSMISSION CORPORATION LTD. SARADAR PATEL VIDYUT BHAVAN, RACE COURSE, BARODA – 390 007. TECHNICAL SPECIFICATION FOR 400/220/33 kV, 500 MVA, 3 PHASE AUTO TRANSFORMER GETCO/E/TS - 4XMER02/R0 Mar12 Sign and Seal of Bidder Page 1 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 SPECIAL INSTRUCTIONS TO BIDDER Please read following instructions carefully before submitting your bid. 1. All the drawings, i.e. elevation, side view, plan, cross sectional view etc., in AutoCAD format and manuals in PDF format, for offered item shall be submitted. Also the hard copies as per specification shall be submitted. 2. The bidder shall submit Quality Assurance Plan with the technical bid. 3. The bidder shall have to submit all the required type test reports for the offered item. In absence of this, the evaluation shall be carried out accordingly as non- submission of type test reports. 4. The bidder must fill up all the points of GTP for offered item/s. Instead of indicating “refer drawing, or as per IS/IEC”, the exact value/s must be filled in. 5. All the points other than GTP, which are asked to confirm in technical specifications must be submitted separately with the bid. 6. The bidder is required to impart training in view of manufacture, assembly, erection, operation and maintenance for offered item, at his works, to the person/s identified by GETCO, in the event of an order, free of cost. The cost of logistics will be bear by GETCO. 7. Please note that the evaluation will be carried out on the strength of content of bid only. No further correspondence will be made. 8. The bidder shall bring out all the technical deviation/s only at the specified annexure. Sign and Seal of Bidder Page 2 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 QUALIFYING REQUIREMENT DATA (For Supply) Bidder to satisfy all the following requirements. 1) The bidder shall be Original Equipment Manufacturer (OEM). The offered equipment have to be designed, manufactured and tested as per relevant IS/IEC with latest amendments. 2) The minimum requirement of manufacturing capacity of offered type, size and rating of equipment shall be THREE times tender/ bid quantity. The bidder should indicate manufacturing capacity by submitting latest updated certificate of a Chartered Engineer (CE). 3) Equipment proposed shall be of similar or higher rating and in service for a minimum period of THREE (3) years and satisfactory performance certificate in respect of this is to be available and submitted. 4) The bidder should clearly indicate the quantity and Single Value Contract executed during last FIVE (5) years, for the offered equipment. Bidder should have executed one single contract during last five years for the quantity equivalent to tender / bid. The details are to be submitted in following format, Sr. ITEMS ORDER ITEMS QUANTITY ORDER STATUS, IF REMARK No SUPP REFEREN FULLY ORDER LIED CE No. & EXECUTED. UNDER TO DATE YES/NO EXECUTION 5) Equipment offered shall have Type Test Certificates from accredited laboratory (accredited based on ISO/IEC Guide 25 / 17025 or EN 45001 by the National accreditation body of the country where laboratory is located), as per IEC / IS / technical specification. The type test reports shall not be older than FIVE years and shall be valid up to expiry of validity of offer. Sign and Seal of Bidder Page 3 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 INDEX Sec. No. Particulars Page no. 1.1 SCOPE : 6 1.1.3 GUARANTEE 6 1.2 TRANSPORT 7 1.3 STANDARDS 7 1.4 DRAWINGS 7 1.5 TYPE OF TRANSFORMER 8 1.6 DESIGN 8 1.7 TANK 9 1.8 UNDER CARRIAGE 11 1.9 CORE 11 1.10 WINDING 13 1.11 INSULATING OIL (Appendix – A) 14 1.12 INSULATION 15 1.13 TEMPERATURE RISE 15 1.14 FREQUENCY 16 1.15 PARALLEL OPERATION 16 1.16 IMPEDANCES 16 1.17 TAP CHANGING MECHANISM 17 1.18 OIL PRESERVING EQUIPMENT 19 1.19 BUSHINGS 19 1.20 COOLING 20 1.21 CENTRE OF GRAVITY 23 1.22 ACCESSORIES 23 1.23 TERMINALS 29 1.24 CURRENT TRANSFORMERS 29 1.25 TERMINAL MARKING 29 1.26 CLEANING AND PAINTING 29 1.27 PACKING AND TRANSPORT 30 1.28 LABLES 30 1.29 INSPECTION 31 1.30.1 INSTALLATION CHECKS 34 1.30.2 COMMISSIONING CHECKS 34 1.30.3 TESTING (Type, Special & Routine) 35 1.30.4 TEST ON TRANSFORMER TANK 37 1.30.5 TEST AT SITE 38 1.31 TESTS ON OLTC 39 1.32 TEST REPORTS 39 1.34 LOSS/DAMAGES 39 1.35 TECHNICAL AND GUARANTEED PARTICULARS 39 1.36 INSRUCTION MANUALS 39 1.37 DEVIATION FROM SPECIFICATION 40 1.38 TRANSFORMER LOSSES AND EVALUATION OF BID 40 1.39 PENALTY FOR HIGHER LOSSES 41 1.40 REJECTION 41 Sign and Seal of Bidder Page 4 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 1.41 TRAINING TO ENGINEERS 41 1.42 TRANSFORMER OIL 42 1.43 QUALITY ASSURANCE PLAN 42 SECTION – II 2.1 SCOPE 44 2.2 CLIMATIC AND ISOKERAUNIC CONDITIONS 44 2.3 TYPE AND RATING: 44 2.4 EARTHQUAKE & WIND DESIGN LOADS 47 2.5 BUSHING CT 47 2.6 NEUTRAL CT 47 2.7 POWER SUPPLY FOR CONTROLS 48 2.8 OIL STORAGE TANK 48 2.9 OIL SAMPLE BOTTLE 49 SCH-A GTP for Power TR 51 OLTC 62 Control Cabinet 64 Clamps & Connectors 66 Appendix - SPECIFICATION OF TRANSFORMER OIL (uninhibited) 68 A Appendix –B 1.0 QUALIFICATION REQUIREMENTS FOR ERECTION 70 TESTING & COMMISSIONING 2.0 ERECTION OF TRANSFORMER 70 3.0 TOOLS REQUIRD FOR ERECTION 71 Annexure-I AUTOMATIC VOLTAGE REGULATING RELAY 73 Annexure- List of documents to be attached 75 C Annexure-II Technical specification for On line moisture and multiple gas 76 analyzer Annexure- Technical specification for Nitrogen Injection Fire Protection 84 III system GTP for NIFPS 93 Sign and Seal of Bidder Page 5 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 SECTION: I DETAIL SPECIFICATION OF 500 MVA, 400/220/33 kV THREE PHASE AUTO TRANSFORMER GENERAL TECHNICAL REQUIREMENTS 1.1 SCOPE: 1.1.1 This section covers the design, manufacture, assembly, inspection, testing at manufacturer’s works, supply and delivery include loading, transportation & unloading on plinth at site, of the 500 MVA, 400/220 kV with 33 kV loaded tertiary winding rated for 167 MVA active connected in YNaOd11, three phase Auto transformers as detailed in the Schedule of requirements, complete with all accessories required for safe, efficient, satisfactory and trouble free operation of the equipment. 1.1.2 The scope of work shall also include EITHER complete erection, testing and commissioning of all the equipments/accessories furnished under this specification OR only supervision of erection, testing and commissioning of all the equipment furnished under this Specification, as indicated in Schedule – A of the commercial bid. 1.1.2.1 Each transformer shall be supplied with two number of Oil storage tank as per cl. no. 2.8 and 3 nos. of oil sampling bottles as per cl. no. 2.9, Fiber optic sensors, On Line Moisture and Gas In Oil Analyser as per Annexure II, Nitrogen Injection System For Protection against The Fire & Explosion as per specification no. GETCO/E/TS-FF/2902 DTD.JUNE 2008, attached with this specification, On line PD measurement, GPS/GRPS/GSM based on line transformer movement tracking system, Condition controlled maintenance free on line breather as per specification. However, Bidder has to quote the requirement of equipment / Material as indicated in Schedule-A of commercial Bid. 1.1.3 GUARANTEE: The bidder shall among other things guarantee the following: i) Quality and strength of materials used. ii) The tenderer shall give the guarantee as satisfactory working of the complete transformer for 36 months from the date of commissioning of equipment or 42 months from the date of receipt of transformer at site, whichever is earlier. Guarantee period will be reckoned from the date of receipt of 100 % accessories and not from the date of receipt of main tank only. Sign and Seal of Bidder Page 6 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 It may be noted that the service guarantee would be applicable even when the transformers are erected and operated through any other agency appointed by the GETCO. 1.2 TRANSPORT: 1.2.1 The equipment to be furnished under this specification shall be packed for transportation in such a manner as may facilitate easy handling and avoiding any damage during transit. 1.3 STANDARDS: 1.3.1 The Power Transformers covered under this specification shall comply with the requirements of the latest edition of IS: 2026 (amended up to date) except specified herein. However, in the event the offered equipment conforms to any other standard, the salient points of difference between the standard adopted and the specified standard shall be clearly brought out in the bid. 1.4 DRAWINGS: 1.4.1 Drawings in AutoCAD format and in hard copy, incorporating the following particulars shall be submitted by the bidder with the bid. i) General outline drawing showing dimensions, wheel loading, net weight of transformer, tap change gear, marshalling box etc. ii) General arrangements of foundations and structural mounting. iii) Sectional views showing the general constructional features and disposition of various fittings and sectional view of Core Coil assembly clearly indicating boltless construction and other necessary specific details. iv) Dimensions of the largest packages to be transported. v) Drawing showing the complete details of all class condenser bushing and other relevant data. vi) Drawings showing details of Buchholtz relay, winding temperature indicator, oil temperature indicator, FO system, air cell, cooling systems, tap changer etc. vii) Drawings for unit coolers. 1.4.2 The successful bidder shall submit the following drawings in AutoCAD format and in hard copy for the approval of the purchaser within commencement period. Sign and Seal of Bidder Page 7 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 i) General out line drawing showing front, side elevation and plan of the transformer and accessories with detailed dimensions. The clearances between HV and LV terminals and ground should also to be shown. ii) Detailed foundation drawings along with structural drawings showing design criteria & loadings. iii) Drawings of each type of bushings, lifting dimensions, clearance between HT and LT terminals and ground, quantity of insulating oil, name plate details etc. showing various weights and ratio of WT – CT, OT-CT, all bushing CT and details of OLTC & RTCC. iv) Large scale drawings of high, medium and low-tension windings of the transformers showing the nature and arrangement of insulators and terminal connections. v) Control and annunciation wiring diagram and drawings showing temperature indicator, FO System, alarm circuits, Buchholz relay, oil surge relay, PRV, MOG, WTI, OTI, AVR relay, OLTC, cooling control etc. vi) Drawing showing construction and mounting details of marshalling boxes. vii) Operation and maintenance guide for transformer and OLTC. viii)Detailed drawing showing wheel loadings and its center of gravity. 1.4.3 The bidder may submit any other drawings found necessary in addition to the drawings mentioned above or as asked during detailed engineering. 1.5 TYPE OF TRANSFORMER: 1.5.1 The transformers shall be of oil immersed type suitable for outdoor installation. The type of working shall be as specified in specific Technical requirements given in Section - II of this Specification. 1.6 DESIGN: 1.6.1 The autotransformer shall be used for bi-directional flow of rated power. The transformer and accessories shall be designed to facilitate inspection, cleaning and repairs and for operation where continuity of supply is the primary consideration. All apparatus shall be designed to ensure satisfactory operation under sudden variations of load and voltage as may be met with under working conditions of the system including those due to short circuits. 1.6.2 All materials used shall be of the best quality and of the class most suitable for working under the conditions specified and shall withstand the variations of temperatures and atmospheric conditions arising under working conditions without inner distortion or deterioration or setting up of undue stresses in any part & also without affecting the strength and suitability of the various parts for the work which they have to perform. Sign and Seal of Bidder Page 8 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 1.6.3 All outdoor apparatus, including bushing insulators with their mountings, shall be so designed as to avoid pockets in which water can collect. All connections and contacts shall be of ample cross-sections and surfaces for carrying continuously the specified current without undue heating and fixed connections shall be secured by bolts or set screws of ample size, adequately locked. Lock nuts shall be used on stud connection carrying current. 1.6.4 Radio Interference and Noise level: The transformer shall be designed with particular attention to the suppression of maximum harmonic voltage, especially the third and fifth so as to minimize interference with communication circuits. The noise level of transformer, when energized at normal voltage and frequency with fans and pumps running shall not exceed, when measured under standard conditions, the values specified in NEMA standard publication TR-I. 1.6.5 The transformer shall be capable of being loading in accordance with IS: 6600/IEC-354. There shall be no limitation imposed by bushings, tap changers etc. or any other associated equipments. 1.6.6 The transformer and all its accessories including CTs etc shall be designed to withstand without any injury, the thermal and mechanical effects of any external short circuit to earth and of short circuits at the terminals of any winding for a period of 3 secs. The short circuit level of the HV and LV system to which the subject transformer will be connected is 40 kA (sym, rms, 3 phase fault on 400 and 220 kV) & 25 kA (sym, rms, 3 phase fault on 33 kV). 1.6.7 Transformer shall be capable of withstanding thermal and mechanical stresses caused by symmetrical or asymmetrical faults on any winding. 1.7 TANK: 1.7.1 The transformer tank and cover or BELL type tank shall be fabricated from good commercial grade low carbon steel suitable for welding and of adequate thickness. The thickness of each side plate shall be indicated in GTP. The tank and the cover shall be of welded construction. All seams shall be welded and where practicable they shall be double welded. The tank wall shall be reinforced by stiffener of structural steel for general rigidity. The tank shall have sufficient strength to withstand without permanent distortion (i) filling by vacuum, (ii) continuous internal gas pressure of 0.35 atmospheres with oil at operating level and (iii) mechanical shock during transportation. The tank cover shall be bolted to the tank and the transformer design shall be such that the tank will not be split between the lower and upper cooler connection for untanking. The tank covers shall be fitted with pockets at the position of maximum oil temperature corresponding to MCR (Maximum Continuous Rating) for RTD sensors and bulbs of oil and winding Sign and Seal of Bidder Page 9 of 96 GETCO/E/TS - 4XMER02/R0 Mar12 temperature indicators. It shall be possible to remove these sensors bulbs without lowering the oil in the tank. The tank wall penetrations shall be leak proof, suitably marked with respective sensor identification. 1.7.2 A man-hole with a welded flange and a bolted cover shall be provided on the tank cover. The man-hole shall be of a sufficient size to ease access to the lower ends of the bushings, terminals etc. 1.7.3 All bolted connections to tank shall be fitted with suitable oil-tight gasket, which shall give satisfactory service under the operating conditions. Special attention shall be given to the methods of making the hot oil-tight joints between the tank and cover as also between the cover and the bushings and all other to ensure that the joints can be remade satisfactorily and with ease, with the help of semi-skilled labours. Where compressible gaskets are used, steps shall be provided to prevent over compression. Bushings, turrets, cover of accessories, holes and other devices shall be designed to prevent any leakage of water into or oil from the tank. There should not be any leakage at least for three years and this should be guaranteed. All the gaskets to be provided shall be of RC70C or RC80C grade. Necessary tests certificates from manufacturer shall be submitted along with acceptance test report. The gasket to be used shall not be older than One year. 1.7.4 Suitable guides shall be provided for positioning the various parts during assembly or dismantling. Adequate space shall be provided between the covers and windings and the bottom of the tank for collection of any sediment. 1.7.5 Lifting eyes or lugs shall be provided on all parts of the transformer requiring independent handling during assembly or dismantling. In addition, the transformer tank shall be provided with lifting lugs and bosses properly secured to the sides of the tank for lifting the transformers either by crane or by jacks. 1.7.6 The design of the tank, the lifting lugs and bosses shall be such that the complete transformer assembly filled with oil can be lifted with the use of those lugs without any damage or distortions. 1.7.7 The tank shall be provided with two suitable copper alloy or any other suitable material lugs for the purpose of grounding. 1.7.8 The tank shall be equipped with the following valves with standard screw connection for external piping. All valves up to and including 100 mm shall be of GM and larger valves shall be of Cast Iron bodies with GM fittings. They shall be of full way type with internal screw and shall open when turned counter clock wise when facing the hand wheel, along with suitable locking in open and close positions. i) One drain valve of adequate size with eccentric reducer and flange, located on the low voltage side of the transformer. This valve shall be equipped with a small sampling cock. The draining valve must be at bottommost location of the tank. Sign and Seal of Bidder Page 10 of 96