SCHEDULE A SR. NO. 1 No.

Transcription

1 SCHEDULE A SR. DESCRIPTION OF MATERIAL QUANTITY Nos. NO. Tender Offered 1. Power Transformer 3500KVA, 11 KV / 6.9KV Voltage Ratio, 183 A / 293 A current ratio, YNyn0 vector, ON cooling, with NGR on LV side. Make: Ashok / Apex / Voltamp/ BHEL/TELK/ Crompton Greaves /ABB/ EASSUN/ AREVA T&D. The detail specifications are as per GTP (Schedule B1) (Section I to V). The transformer is required for CCPP Unit-2 black start facility at Dhuvaran. 1 No. Type : 3 phase, oil filled normal continuous rating (KVA) : 3500 KVA No load voltage ratio (KV) : 11 / 6.9 KV Winding material : Copper. Connection (A) High voltage : Star (Neutral Brought out) (B) Low voltage : Star (Neutral Brought out) Vector Group : YNyn0 Tapping on H.V. Side for giving voltage variation of HV : + 7.5% to 7.5% in steps of 2.5% Type of Tap changer: OFF LOAD Circuit tap changer. Temperature rise of oil / WDG, by thermometers resistance method over specified Ambient temp. of 50 Degree Cent. At Principal Tap: 40/45 Degree cent. No load loss at rated current at 75 C at Normal Tap : KW Max. (Tol. As per IS) Load loss at rated current at 75 C at Normal Tap : - 20 KW Max. (Tol. As per IS) Terminal (HV/LV/Orientation): Cable Box/Cable Box / 180 Degree Impedance at rated current at 75 Degree: 6.25 % as per (Tol. As per IS) Fitting : Rating and diagram plate, Terminal Marketing Plate, lifting and jacking lugs, Silica gel breather, Bottom drain cum filter valve, Top filter valve, Thermometer pocket, Conservator with oil filling hole and drum plug, flat rollers, PRV, oil temperature indicator, winding temperature indicator, Buchholz relay with 2 Nos. shut-off valves, Magnetic oil level gauge, Marshalling Box. Paint: Epoxy as per I.S. 1. The estimated cost of this tender is Rs..31,72, Cost of the Tender Documents is Rs. 1,000/- which is non refundable. Details of Tender fees are as under: Demand Draft No. dtd. of Bank Rs. For Rs. 1, EMD amount to be paid is Rs.. Details of the EMD are as under: Demand Draft No. dtd. of Bank Rs. For Signature And seal of Bidder Page 1 of 27

2 4 Delivery Period: The delivery schedule of the materials against this tender shall be commencing within one month and completed in one quarter thereafter. The delivery period will be reckoned from the date of receipt of order. The inspected material is to be dispatched within 15 days from the date of Dispatch Instructions. 5 Bidder shall have to arrange for inspections and routine tests on subject transformer and terminal connectors at their works in presence of GSECL Engineer. 6 The tenderers are requested to clarify whether they have laboratory having facility to carry out routine tests as mentioned in GTP. 7 The Bidder shall furnish four sets of the type test reports for the type and Design of transformer offered by him along with the offer. The Type Test report shall not be older then 5 (five) years prior to the date of opening of the Bid, otherwise the offer will not be considered. 8 Guarantee: - The Guarantee from the date of supply shall be as per Clause No.46 of the Commercial Terms & Conditions for 60 months as applicable. 9 Performance Guarantee:- The performance Guarantee shall be as per Clause No. 47 of Commercial Terms & conditions, amounting to 10% of the order value ( End Cost) shall be paid either in form of Bank Guarantee or in Cash / Demand Draft by you, immediately on commencing the supply for satisfactory performance of the materials. 10 EMD cover must contain the following documents (a, b & c) : (a) Details & Documents as per clause No. 11 (Commercial terms and conditions) of this tender. However company would accept B.G. issued by all Public Sector Banks & private Banks like IDBI Bank, UTI Bank, HDFC Bank & ICICI Bank only. (b) List of Orders executed during last three (3) years from the date of publication of tender notice (including supplied made to erstwhile GEB) for the tendered items. (c) Vender Registration Certificate: Irrespective of the bidder being Regular supplier or new entrant to the GSECL, the copy of valid vendor registration certificate must be enclosed otherwise the offer is likely to be rejected. 10. In case Corporation finds that there is an attempt of cartel in the prices. Corporation reserves the right to consider or reject any or all the parties offer without assigning any reason thereof. 11 Corporation reserves the right to terminate the contract at any time, without assigning any reason, whatsoever, by giving a notice period of one month from the date of notice of termination of the contract. Suppliers will not be entitled for any compensation/ damages / losses, whatsoever, on account of such termination of the contract. Other text portion of Clause No. 57 Termination Of Contract will also be applicable. Signature And seal of Bidder Page 2 of 27

3 SCHEDULE B1 QUALIFYING REQUIREMENT FOR BIDDERS FOR 11/6.9 KV, 3500 KVA Transformer for GSECL Dhuvaran CCPP 1. Bidder should be a manufacturer, who have designed, manufactured 11 KV Class transformers and successfully tested as per IS/IEC or any equivalent standard, which are in successful operation for not less than 3 years any where as on the date of bid opening. 2. Bidders not meeting the requirements at 1 above but where the manufacturer has designed, manufactured, tested and supplied similar equipment of at least the lowest rating specified and which are in successful operation on the date of bid opening can also participate provided they have valid on going collaboration with a manufacturer, who has at least 10 years experience in the design, manufacture and testing of the equipment of the type and class specified, which have been in satisfactory service for a period of at least 7 years. In such an event, the bidder shall furnish, along with his bid, documentary evidence for the same and an undertaking from the collaborator accepting joint and several liability all obligations under the contract. 3. Bidder shall invariably furnish documentary evidence (client s certificate) in support of the satisfactory operation of the equipment as specified above. 4. Further, the Bidder shall furnish, with his bid type, test reports as per IS/IEC or any equivalent standard of the equipment being offered. However, the type test reports of the collaborator for equipment similar to the type as offered, would be considered for the purpose of these qualifying requirements. 5. The manufacturer shall have adequate design, infrastructure and manufacturing facilities and capacity and procedures including quality control. 6. Notwithstanding anything stated above, the owner reserves the right to access bidder s capability and capacity to perform the contract should circumstances warrant such an assessment in the overall interest of the owner. Signature And seal of Bidder Page 3 of 27

4 SECTION I TECHNICAL SPECIFICATION FOR OUTDOOR TYPE POWER TRANSFORMER OF 11 KV/6.9 KV CLASS, 3500 KVA GENERAL REQUIREMENTS FOR TRANSFORMER : 1.0 SCOPE: This specification covers, engineering, manufacture, assembly, stage testing, and inspection and testing before supply and delivery at site of oil immersed, naturally cooled 3 phase 11 kv/6.9kv Transformer for outdoor use along with commissioning at site. 1.1 It is not the intent to specify completely herein all the details of the design and construction of equipment. However the equipment shall conform in all respects to high standards of engineering, design and workmanship and shall be capable of performing in continuous commercial operation up to the Bidder s guarantee, in a manner acceptable to the purchaser, who will interpret the meanings of drawings and specification and shall have the power to reject any work or material which, in his judgment is not in accordance therewith. The offered equipment shall be complete with all components necessary for their effective and trouble free operation. Such, components shall be deemed to be within the scope of Bidder s supply irrespective of whether those are specifically brought out in this specification and / or the commercial order or not. 1.2 Standard Ratings: The Standard Ratings shall be 3500 KVA. 2.0 CODES AND STANDARDS 2.1 The design, manufacture and performance of equipment shall comply with all currently applicable statues, regulations and safety codes in the locality where the equipment will be installed. Nothing in this specification shall be construed to relieve vendor of this responsibility. 2.2 Material conforming to other internationally accepted standards, which ensure equal or higher quality than the standards mentioned above, would also be acceptable. In case the Bidders who wish to offer material conforming to the other standards, salient points of difference between the standards adopted and the specific standards shall be clearly brought out in relevant schedule. Four copies of such standards with authentic English translations shall be furnished along with the offer. The materials shall conform in all respects to the relevant Indian / International Standard Specification, with latest amendments thereof, some of them are listed below: Indian Standard Title International & Internationally recognised standard ISS -2026/1977 Specification for Power Transformer IEC 76 ISS Outdoor distribution Transformer upto and including 100 kva IS Specification for Copper wire rod ASTM B-49 ISS -3347/1967 Specification for porcelain Transformer DIN 42531,23,3 bushing ISS-335/1983 Specification for Transformer Oil BS 148, D-1473, D IEC Pub ISS 5/1961 Specification for colors for ready mixed paints ISS /1973 Specification for High Voltage Porcelain bushings ISS /1974 Specification for Low Voltage bushings ISS Specification for Outdoor Bushings DIN to 33 Signature And seal of Bidder Page 4 of 27

5 ISS Specification for Al Wire rods ASTM B ISS Specification for Insulating Kraft Paper IEC 554 ISS Specification for Insulating Press Board IEC 641 ISS- 6600/1972 Guide for loading of oil Immersed IEC 76 Transformers ISS-649 Testing of Steel Sheets & Strips For Magnetic circuits ISS-6162(Part-I&II) Paper covered Aluminum Conductor ISS ISS-4257 ISS ISS ISS-1866 Installation, Maintenance Of Transformers Dimension for clamping arrangement for bushings (for porcelain and metal parts) Rectangular conductors for electrical machine Silica gel ode of practice for maintenance & supervision of Mineral insulating oil in equipment IS : 3639 IS : 335 Fitting and Accessories for power Transformers Insulating oil for transformers and Swichgear. 3.0 OPERATIONAL REQUIREMENTS 3.1 VOLTAGE AND FREQUENCY VARIATIONS a) Transformers shall operate without injurious heating, on any tap, under the following conditions, provided increase in voltage is not accompanied by reduction in frequency : i) At rated KVA, with voltage variation of ± 10% of the voltage corresponding to the particular tap. ii) At rated current, with 105% rated voltage. 3.2 OPERATION TH COOLING EQUIPMENT OUTAGE Starting from hot conditions, transformers shall be capable of operating, without exceeding permissible temperature rises and with all forced cooling out of operation, under the following conditions : i) At rated voltage and frequency for not less than 1 hour without load current. ii) At rated KVA for not less than 10 minutes. 3.3 OPERATION UNDER OVERLOADS It shall be possible to operate transformer as per loading guide IS: 6600 up to overloads of 150%. There shall be no limitations imposed by bushings, tap changers, auxiliary equipment etc. to meet this requirement. 4.0 CONSTRUCTIONAL FEATURES : MATERIAL - CRGO/ AMORPHOUS METAL : CRGO Material: The core shall be of NEW high grade cold rolled grain annealed steel lamination having low loss and good grain properties, coated with hot oil proof insulation, bolted together and to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core losses with continuous working of the transformers. The value of the maximum flux density allowed in the design and grade of lamination used shall be clearly stated in the offer. Core Clamping for CRGO : MS channel shall be used on top and bottom Core Channel on LV side to be reinforced at equidistance, if holes / cutting is done for LT lead in order to avoid bending of channel. MS Channels shall be painted with oil-resistant paint. The transformers core shall be suitable for over fluxing (due to combined effect of voltage and frequency) upto 12.5% without injurious heating at full load conditions and shall not get saturated. The Bidder shall furnish necessary design data in support of this situation. The nominal flux density in any part of the core shall not exceed 1.65 Tesla at 1.0 p.u.voltage The vendor shall furnish necessary design data in support of this stipulation. No load current shall not exceed 2% of full load current and will be measured by energizing the transformer at 6.9 KV, 50 c/s on the secondary. Increase of voltage of 6.9 KV by 12.5% shall not increase the no load current by Max. 6% of full load current. Test for magnetic balance by Signature And seal of Bidder Page 5 of 27

6 connecting the LV phase by phase to rated phase voltage and measurement of an, bn, cn voltage will be carried out. Clamping and Tie-rods shall be made from HT steel & shall be parkarised. AMORPHOUS METAL: The core shall be high quality amorphous ribbons having very low loss formed into wound cores of rectangular shape, bolted together to the frames firmly to prevent vibration or noise. The complete design of core must ensure permanency of the core loss with continuous working of the transformers. The value of the flux density allowed in the design shall be clearly stated in the offer. Curve showing the properties of the metal shall be attached with the offer. Core Clamping for Amorphous metal Transformers Core clamping shall be with top and bottom U-shaped core clamps made of sheet steel clamped HT steel tie rods for efficient clamping. MS core clamps shall be painted with varnish or oil-resistant paint. MS rods shall be used as tie rods. Suitable provision shall be made in the bottom core clamp / bottom plate of the transformer to arrest movement of the active part. NOTE: "Equal weightage shall be given to the transformers with Amorphous metal core & CRGO " Similar parts, particularly removable ones, shall be interchangeable Screws, studs, nuts and bolts shall be as per Indian Standards Nuts, bolts, pins used inside the transformers and tap changer compartments shall be locked Exposed parts shall not leave pockets where water can collect Internal design of transformer shall ensure that air is not trapped in any location Facility shall be provided for lubrication of bearings and mechanisms. Mechanisms shall be constructed of non- corrodible materials Materials in contact with oil shall be such as not to contribute to the formation of acid in oil. Surface in contact with oil shall not be galvanized or cadmium plated Labels, indelibly marked, shall be provided for all accessories like relays, switches, fans, current transformers etc. 4.2 CORE The magnetic circuit shall be of core type construction. The core shall be built out of high grade, non-ageing, low loss and high permeability, cold rolled grain oriented silicon steel laminations After being sheared the laminations shall be treated to remove all burrs. Both sides of the laminations and the cut edges shall be treated with carline insulation The finally assembled core shall be free from distortion. It shall be rigidly clamped to ensure adequate mechanical strength and to prevent vibrations during operations The core clamping structure shall be designed to minimize eddy current loss The core shall be provided with lugs suitable for lifting the complete core and coil assembly The core and coils assembly shall be so fixed in the tank that shifting will not occur during transport or short circuits All steel sections used for supporting the core shall be thoroughly sand-blasted, after cutting drilling and welding. 4.3 INTERNAL EARTHING All internal metal parts of the transformers, with the exception of individual laminations, core bolts and their individual clamping plates; shall be earthed. Core clamps and core bolts shall be insulated from the core by class B insulation unless other insulation is approved by Purchaser The top clamping structure shall be connected to the tank by a copper strap. The bottom clamping structure shall be earthed by one or more of the following methods. a) By connection through vertical tie-rods to the top structure. b) By direct metal to metal contact with the tank base. c) By a connection to the top structure on the same side of the core as the main earth connection to the tank The magnetic circuit shall be connected to the clamping structure at one point only, through a link placed in or accessible position beneath an inspection opening on the tank cover. The link shall be on the same side of the core as the main earth connection in above When the magnetic circuit is sub-divided by oil ducts or insulated barriers above 0.25 mm thick, tinned copper strip bridging pieces shall be inserted to maintain electrical continuity between packets Coil clamping rings of metal at earth potential, shall be connected to the adjacent core clamping structure on the same side as the main earth connection in above. Signature And seal of Bidder Page 6 of 27

7 5.0 WINDINGS (Uniform Winding) Materials: - Only Super enamel covered copper Conductor or Double paper covered copper conductor shall be used for 11 KV, 3500 KVA. 5.1 Windings shall be subjected to a shrinking and seasoning process, so that no further shrinkage occurs during service. Adjustable devices shall be provided for taking up possible shrinkage in service. 5.2 Coils shall be supported at frequent intervals by means of wedge type insulation spacers permanently secured in place and arranged to ensure proper oil circulation. To ensure permanent tightness of winding assembly, the insulation spacers shall be dried and compressed at high pressure before use. 5.3 Windings shall not contain sharp bends which might damage the insulation or produce high dielectric stresses. No strip conductor wound on edge shall have width exceeding six times the thickness. 5.4 Materials used in the insulation and assembly of the windings shall be insoluble, non-catalytic and chemically inactive in the hot transformer oil, and shall not soften or be otherwise affected under the operating conditions. 5.5 All threaded connections shall be locked. Leads from the winding to the terminal board and bushings shall be rigidly supported to prevent injury from vibration. Guide tubes shall be used where practicable. 5.6 Windings and connections shall be braced to withstand shocks during transport or short circuits. 5.7 Coil clamping rings shall be steel or of a suitable insulating material built from slat laminations. 5.8 Permanent current carrying joints in the windings and leads shall be welded or brazed, clamping bolts for current carrying parts inside oil shall be made of oil resistant material which shall not be affected by acidity in the oil, steel bolts, if used, shall be suitably treated. 5.9 Terminals of all windings including unloaded stabilizing windings shall be brought out of the tank through bushings for external connections Windings shall be of copper unless specifically approved by the purchaser. 6.0 INSULATION MATERIAL : a) Material: Electrical grade insulation Kraft Paper of standard make or better material subject to approval of the purchaser. Pressboard of standard make or better material subject to approval of purchaser. b) All spacers, axial wedges / runners used in windings shall be made of pre-compressed Pressboard solid, conforming to type B 3.1 of IEC In case of cross-over coil winding of HV all spacers shall be properly sheared and dovetail punched to ensure proper locking. All axial wedges / runners shall be properly milled to dovetail shape so that they pass through the designed spacers freely. Insulation shearing, cutting, milling and punching operations shall be carried out in such a way, that there should not be any burr and dimensional variations. 7.0 TANK 7.1 Tank shall be made from good commercial grade low carbon steel and shall be of welded construction 7.2 Tank shall be designed to permit lifting, by crane or jacks, of the complete transformer assembly filled with oil. 7.3 Tank shall be braced to withstand full vacuum of 760 mm of mercury and internal pressures during normal and abnormal condition such as short circuit inside the transformer. (See also pressure test specified in Section 19.1.(e)) 7.4 Suitable guides shall be provided in the tank for positioning the core and coil assembly. 7.5 Adequate space shall be provided at the bottom of the tank for collection of sediment. 7.6 The transformer base shall be designed to permit skidding of the complete transformer unit in any direction, when using plates or rails. The under base shall be detachable unless transport facilities permit a fixed base. 7.7 The transformer top shall be provided with a detachable cover with a bolted flanged gasket joint. Lifting lugs shall be provided for removing the cover. The surface of the cover shall be suitably sloped so that it does not retain rain water. 7.8 When specified, the tank shall have an oil-tight bolted flanged gasket joint near the base of the transformer, so that the tank can be lifted off to have access to core and coils. Suitable projecting guides shall be provided on the core and coil assembly, to facilitate removal of the tank without lifting the coils. It shall be feasible to weld-off the flanged joint at the base in case of oil leakages. 7.9 Necessary measures shall be adopted like increased clearances and separate aluminum shields to minimize eddy current losses in large capacity and high impedance transformers. Signature And seal of Bidder Page 7 of 27

8 7.10 The material used for gaskets shall be cork-neoprene or approved equivalent. Gasket joints for tank and manhole covers, bushings and other bolted attachments shall be so designed that the gasket will not be exposed to the weather. Stops to prevent crushing shall be provided for compressible gaskets. 8.0 UNDER CARRIAGE The under carriage of the transformer shall be provided with detachable steel flanged wheels of flat rollers as specified. Flanged wheels shall be spaced to allow specified rail gauge. Wheels shall be provided with suitable bearings which will resist rust and corrosion and shall be equipped with fittings for lubrications. Unless otherwise approved, it shall be possible to swivel the wheels or rollers in two directions, at right angles to or parallel to the main axis of the transformer, thereby permitting movement in two directions. The wheels or rollers will be swiveled after jacking the transformer and they shall be lockable in the two positions. 9.0 OIL Transformer and associated oil filled equipment shall be supplied with first filling of oil plus 10% extra in non returnable drums. The oil shall confirm to IS: 335. No inhibitors shall be used in the oil. The make of oil shall be subject to Purchaser s approval BUSHINGS 10.1 Bushings for voltages of 66 KV and above shall be of the oil filled condenser type and shall preferably be of the draw lead type to facilitate removal. For voltage below 66 KV solid porcelain or oil communicating type bushings may be used Condenser type bushings shall be provided with a) Oil level gauge. b) Oil filling plug and drain valve if not hermetically sealed. c) Taps for capacitance test. d) Steers rings and lower end shields KV bushings shall be used for 6.9 KV and 3.3 KV service When bushings have an under-oil end of re-entrant form, pull through lead shall be fitted with a gas bubble deflector Oil for the bushings shall be same as transformer oil Bushings rated for 400A and above shall have non-ferrous flanges and hardware CABLE BOXES AND DISCONNECTING CHAMBERS When connection is by cable, unless otherwise approved, disconnecting chamber shall be provided for disconnecting and moving away the transformer without unsealing the cables or draining oil from the main tank, leaving the cable box or chamber. Behind on Purchaser s external supports Cable boxes and sealing ends shall be complete with jointing materials, compound and all other accessories including wiping glands, armour, earthing clamps, and tinned copper crimping type solder less lugs shall be in scope of supply The cable box shall have all standard facilities including fitting and drain plugs, relief vent, level glass and body earth terminals The disconnecting chamber shall preferably be air insulated. If oil insulated, the oil shall be segregated from transformer tank oil or cable box oil. Bushings, oil filling and drain plugs, relief vent, level glass, and removable cover shall be provided for the disconnecting chamber. Plates through which high current carrying conductors pass, shall be non-magnetic unless otherwise approved by Purchaser Phase to phase and phase to ground clearances within the chamber shall be subject to Purchaser s approval TRANSFORMER COOLING EQUIPMENTS 12.1 BUILT-ON RADIATORS Unless otherwise approved, tank mounted radiators shall be of the detachable type with bolted flanged connections. The following accessories shall be provided for each radiator : a) Shut off valves and blanking plates on transformer tank at each point of connection. b) Top and bottom shut off valves and blanking plates on each radiator. c) Lifting lugs. d) Top oil filling hole with cap. e) Air release plug at top. f) Oil drain plug at bottom Signature And seal of Bidder Page 8 of 27

9 13.0 TAP CHANGING GEAR 13.1 OFF CIRCUIT TAP CHANGING GEAR The off circuit tap changer shall be opera-table by means of an operating handle brought outside the tank. It shall be equipped with an indicating device to show the tap in user and shall be provided with a locking arrangement to lock the switch in position. The tapping shall be provided on HV side to suit variation in voltage on HV side. The rotary tap changing switch shall be of approved design ( design details and drawings to be supplied with the offer ) suitable for external manual operation on off load. Cast indicating plate with switch with a movable pointer to be provided to clearly show tap position number CONTROL CABINETS. OFFLOAD TC local control cabinet, Marshalling box and cooler Control cabinet. Local Temperature indicator meter for OTI & WTI 13.1 Execution Outdoor IP 54 as per IS: Mounting Tank mounted or mounted on a separate foundation Wiring All alarm and trip circuits shall be wired for auxiliary DC Supply as specified. General Specification In accordance with enclosed Specification. Special requirement Bottom shall be at least 600 mm from floor level. Top Surface shall be sloped. Indicating lamps and meters Shall be covered by a glass Window FITTINGS AND ACCESSORIES The following fittings and accessories shall be provided: 15.1 Inspection manhole(s) with cover(s) on the top cover of the transformer Lifting lugs or eyes for lifting of fully assembled transformer by crane Jacking pads, at least four in number, at suitable height, for lifting the complete transformer filled with oil Lifting arrangement for core and coils Hauling eyes on each face of the transformer Skids at the bottom of the transformer when specified 15.7 Earthing pads: Two earthing pads of copper or other no corrodible material on transformer tank together with clamp type terminals suitable for Purchaser's earthing conductors. Suitable earthing terminals on cable boxes and separately mounted radiator banks Neutral earthing bar of copper of specified section installed from the neutral bushing to ground level suitably supported along its run on porcelain insulators, together with clamping arrangements at neutral bushing and for to Purchaser s earth conductors. The NGR of 3500 KVA X'mer for 6.9 KV side is required. The specification as below. a) Rated voltage KV b) Rated current A c) Rated duty - 10 Sec d) Rated Resistance % e) Temp. rise over 50 C amb. f) Service - Out door g) IP 43 as per IS Terminal marking and rating plates shall be as per IS: Signature And seal of Bidder Page 9 of 27

10 15.10 Conservator (for transformer ratings as per IS: 2026) : The conservator shall be sufficient volume to maintain the oil seal from the minimum ambient temperature of - 50 C, with oil level varying within the minimum and maximum visible levels. The conservator shall be provided with the following accessories : a) Filling plug, sump and drain valve. b) 150 mm diameter magnetic type oil level gauge with low oil level alarm contacts or a prismatic oil sight gauge both provided with markings for minimum oil level and oil level at 30 C as specified. c) A bolted cover for cleaning. d) Valve for shutting off oil to the transformer. e) Weather proof de hydrating breather with silica gel and oil seal to eliminate constant contact with the atmosphere, mounted at a level of about 1400 mm above ground level VALVES The following valves shall be included on the transformer tank Main tank drain valve with flanged or threaded connection Top filtering valve with plug located on the same side as the main drain valve Bottoms filter connection with plug to drain oil from the lowest part of the tank. This connection shall not be tapped through the bottom of the transformer Oil sampling devices at top and bottom of the main tank. These shall be distinct from other valves Adequate number of air relief vents Two plugged pipe outlets at top for applying vacuum. All valve opening shall be plugged or blank flanged Valves for the cooler systems are indicated in the respective sections. These valves shall be lockable in closed or open positions and shall be provided with an indicator to show position of the valve Pressure Relief Devices: A pressure relief vent mounted on the tank shall be provided for relieving pressure within the transformers. It shall operate for pressure less than the hydraulic test pressure for the tank GAS AND OIL ACTUATED RELAY (BUCCHOLZ RELAY) A double float type Buccholz relay as per IS: 3637/8 shall be provided whenever called. All gas evolved in the transformer shall collect in this relay. The relay shall be provided with a test cock suitable for a flexible pipe connection for checking its operation. A copper tube shall be connected from the gas collector to a valve located about 1.25 M above ground level to facilitate sampling with the transformer in service. The device shall be provided with two electrically independent ungrounded contacts, one for alarm on gas accumulation and the other for tripping on sudden rise of pressure TEMPERATURE INDICATORS OIL TEMPERATURE INDICATOR Transformer shall be provided with a 150 mm dial type temperature indicator for top oil temperature indication. The indicator shall have adjustable, electrically independent ungrounded alarm and trip contacts, maximum reading points and resetting device. (Additionally Electronic Temperature indicator with Alarm & Trip settings equipped with suitable RTD shall be provided so that the temperature can be shown on breaker panel at Remote end approx. 800 Mtr away.-excluding cables) WINDING TEMPERATURE INDICATOR A device for measuring the hot spot temperature of the winding shall be provided when called for It shall comprise of the following. Temperature sensing element. a) Image coil. b) Current transformer c) 150 mm dia local indicating instrument with two adjustable electrically independent ungrounded contacts, two for winding temperature alarms. d) Calibration device. e) Automatic ambient temperature compensation. In addition to the above, the following remote indication equipment shall be provided when called for. a) Analogue signal transmitter. Signature And seal of Bidder Page 10 of 27

11 b) Remote indicating, flush mounted instrument for mounting on breaker panel at Remote end approx. 800 Mtr away.-excluding cables RADIO INFLUENCE AND NOISE LEVEL 16.1 The transformers 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 when energized at normal voltage and frequency with fans and pumps running shall not exceed 80 db when measured under standard conditions PAINTING 17.1 The interior of all transformer tanks and other oil filled chambers and internal structural steel work shall be cleaned of all scale and dust by shot-blasting unless otherwise approved. These surfaces shall be painted with not less than two coats of heat resistant, oil insoluble and insulating varnish. Steel surfaces exposed to the weather shall be thoroughly cleaned and applied a priming coat of zinc chromate. The second coat shall be of an oil and weather resistant nature, preferably of distinct colour from the prime and finish coats. The final coat shall be of a glossy oil and weather resisting non fading paint of specified shade All exposed bolts, nuts and washers shall be of galvanized steel unless otherwise approved Metal parts not accessible for painting shall be made of corrosion-resistant material. Machined finished and bright surfaces shall be coated with a suitable compound and wrapped Interior surfaces of mechanism chambers and knocks shall receive three coats of paint after proper cleaning the final coat shall be of a light-coloured anti condensation paint TESTS Transformers shall be completely assembled at works to ascertain that all parts fit correctly. The equipment offered shall be fully type tested by the bidder or his collaborator as per the relevant standards. The type test must have been conducted on a transformer of same design. The Bidder shall furnish four sets of type test reports along with the offer. Offers without type test reports will be treated as Non-responsive. b) Special tests other than type and routine tests, as agreed between purchaser and Bidder shall also be carried out as per the relevant standards. c) The requirements of site tests are also given in this clause. d) The test certificates for all routine and type tests for the transformers and also for the bushings and transformer oil shall be submitted with the bid ROUTINE TEST All the Routine tests as per IS shall be performed on transformers. The following additional points may be noted: a) Resistance of winding shall be measured at principal and the two extreme taps. b) Impedance voltage shall be measured at principal and the two extreme taps. c) No load loss and exciting current shall be measured at rated frequency at 100% and 110% rated voltage. These tests shall be done before and after impulse tests if the later are specified. Exciting current shall be measured on each phase and recorded. d) No load loss and exciting current shall be measured and recorded with 415V, 3 phase 50 Hz input on LV side (assuming LV is rated higher than 415V). e) Oil Pressure Test: All oil filled compartments shall be filled with transformer oil and subjected to a pressure of 0.35 Kg/cm 2 above the pressure that would obtain under normal conditions with full head of oil. The pressure shall be maintained for 12 hours during which time no oil leakage shall occur. When heat run test is specified the oil pressure test shall be performed immediately after the heat run. Otherwise the test may be performed at ambient temperature TYPE TESTS Vendor shall quote extra itemized prices for performing the following tests: a) Impulse Test: This shall include chopped wave test. Itemized prices shall be given for : i) Impulse test on one leg (HV & LV) of the transformer. ii) Impulse test on all legs of the transformer. b) Temperature rise test. Signature And seal of Bidder Page 11 of 27

12 c) Measurement of zero-sequence impedance. d) Measurement of acoustic noise level. e) Measurement of tan δ and capacitance of each winding to earth (with all other windings grounded and between all windings (connect together) to earth. f) Short circuit impedance of each limb of the transformer with single phase voltage from both H.T and L.T. sides. This is required to check mechanical displacement between windings. g) Partial discharge test h) Switching surge withstand test 18.3 TESTS AT SITE: The purchaser reserves the right to conduct all tests on Transformer after arrival at site and the manufacturer shall guarantee test certificate figures under actual service conditions AUXILIARY EQUIPMENT All auxiliary equipment shall be tested as per the relevant IS. Test certificates shall be submitted for bought out items. High voltage withstand test shall be performed on auxiliary equipment and wiring after complete assembly TEST REPORTS Four copies of preliminary test results shall be submitted for Purchaser s approval before dispatch of transformer. Additional bound copies as per enclosed distribution schedule of complete test results including all tests on transformer, auxiliaries, bushings and current transformer characteristics shall be furnished with the transformer. Also, test report of transformer oil should be submitted LOSSES 19.1 The design of the transformer should be such as to have minimum possible No load and load losses as per design criteria of the rating of the transformer The bidder should guarantee individual No load loss and load loss without any positive tolerance. The bidder should also guarantee the total losses at 50% and 100% load condition (50% and 100% of rated KVA rating at rated voltage and frequency and at 75 deg centigrade without any positive tolerance For the purpose of evaluation of the bids for the transformer, Capitalized cost of transformer shall be worked out. The offers will be compared on capitalized cost of the transformer 19.4 For the purpose of evaluation of bids, the quoted load losses and iron losses shall be increased by 10% to reflect + 10% tolerance as permitted by ISS. NOTE:- The tolerance specified herein is for total losses i.e. No load losses and load losses. The tolerance on individual losses shall be as per ISS Transformer with losses specified by bidder will be capitalized during bid evaluation worked out by following formula Capitalized cost of the Transformer = IC + (A x Wi) + (B x Wc) Where IC= Initial cost of Transformer (without tax) as quoted by the Bidder A factor = cost of No Load losses in Rs / Watt = Rs./Watt B factor = cost of Load Losses in Rs/Watt = Rs./Watt Wi = No load losses quoted by the manufacturer in watt Wc = Load losses quoted by the manufacturer in watt 19.6 Penalty for Non Performance In the case of order if the figures of losses measured during tests are found to be higher than the figures guaranteed plus 10% tolerance allowable, the transformer at the option of the board will be rejected or accepted with the reduction in price at under For, No Load Rs. 553=00 Rs / Watt. Load losses at 100% Rs. 180=00 Rs/Watt Signature And seal of Bidder Page 12 of 27

13 20.0 REJECTION Purchaser may reject any transformer if during tests or service any of the following conditions arise : 20.1 No load loss exceeds the guaranteed value by 20% or more Load loss exceeds the guaranteed value by 20% or more Impedance value exceeds the guaranteed value by ± 10% or more Oil or winding temperature rise exceeds the specified value by 5 C Transformer fails on impulse test Transformer fails on power frequency voltage withstand test Transformer is proved to have been manufactured not in accordance with the agreed specification Purchaser reserves the right to retain the rejected transformer and take it in to service until the Seller replaces, at no extra cost to Purchaser, the defective transformer by a new transformer Alternatively, the Seller shall repair or replace the transformer within a reasonable period to Purchaser s satisfaction at no extra cost to the Purchaser GUARANTEE FOR THE TRANSFORMERS; 1) Guarantee period shall be 60 months from the date of supply. 2) The supplier shall return guarantee failed transformers duly repaired and tested as per approved GTP and tender specification within 30 days from the date of receipt at repair shop without any cost, failing which bank guarantee shall be encased without any notice and all business will be stopped with the said supplier at least for a period of 3 years.this clause itself shall be the notice to the supplier about encashment of Bank Gurantee incase of his failure to adhere to timelines & no separate notice will be survied. 3) After intimation of failure of transformer failed within guarantee period, Supplier will arrange for the transport & insurance of guarantee period failed transformer to firm s works (And back to GSECL site) at the cost of supplier. On receipt of guarantee period failed transformer at firm s works, the external inspection will be carried out by the representative of GSECL not below the rank of Junior Engineer. The cost of any outer component damage not because of supplier s fault and required to be provided will be reimbursed to the supplier as per the approved rate of GSECL on the strength of joint external inspection report. No. internal inspection of failed unit is to be carried out in presence of representative of GSECL. However, the supplier may prepare an internal inspection report of failed unit for his study and analysis. If required, such analysis shall be furnished to GSECL. Testing of transformer will be done in presence of company s Engineer to ensure losses as per GTP, Transformer found with higher losses than GTP will not be accepted and cost thereof will be recovered. The new Transformers supplied in this circumstances must as per GTP submitted with tender and shall match the losses offered by the supplier as per Tender. The testing of each G.P. failed transformers will be carried out for all acceptance test as per the relevant standard where no load losses and load losses are also required t be maintained identical as per GTP attached 22.0 SPARES Bidder shall quote itemized prices for recommended spares, including the following: 22.1 Complete set of gaskets One bushing of each type Dial type temperature meter 22.4 Complete set of winding temperature indicating equipment INSPECTION: All tests and inspection shall be made at the place of manufacturer and unless other wise especially agreed upon the manufacturer and the purchaser at the time of purchase. The manufacturer shall afford the inspector representing the purchaser all reasonable facilities, without charge to satisfy him that the material is being furnished in accordance with specification. The manufacturer shall provide all services to establish and maintain quality of workman ship in his works and that of his sub-contractors to ensure the mechanical / electrical performance of Signature And seal of Bidder Page 13 of 27

14 components, compliance with drawings, identification and acceptability of all materials, parts and equipment as per latest quality standards of ISO Along with the bid the manufacturer shall prepare Quality Assurance Plan identifying the various stages of manufacture, quality checks performed at each stage and the Customer hold points. The document shall also furnish details of method of checking, inspection and acceptance standards / values and get the approval of purchaser or his representative before proceeding with manufacturing. However, purchaser or his representative shall have the right to review the inspection reports, quality checks and results of manufacturer s in house inspection department which are not customer hold points and the manufacturer shall comply with the remarks made by purchaser or his representative on such reviews with regards to further testing, rectification or rejection etc. Manufacturer should submit the list of equipment for testing along with latest calibration certificates to the purchaser. Purchaser shall have every right to appoint a third party inspection to carryout the inspection process. The purchaser has the right to have the test carried out at his own cost by an independent agency wherever the dispute regarding the quality of supply. Purchaser has right to test 1% of the supply selected either from the stores or field to check the quality of the product. In case of any deviation purchaser have every right to reject the entire lot or penalize the manufacturer, which may leads to blacklisting among other things QUALITY ASSURANCE PLAN: 24.1 The Bidder shall invariably furnish following information along with his bid, failing which his bid shall be liable for rejection. Information shall be separately given for individual type of equipment offered. i. Statement giving list of important raw materials, names of sub-suppliers for the raw materials, list of standards according to which the raw materials are tested. List of tests normally carried out on raw materials in the presence of Bidder s representative, copies of test certificates. ii. Information and copies of test certificates as in (I) above in respect of bought out accessories. iii. List of manufacturing facilities available. iv. Level of automation achieved and list of areas where manual processing exists. v. List of areas in manufacturing process, where stage inspections are normally carried out for quality control and details of such tests and inspection. vi. List of testing equipment available with the bidder for final testing of equipment along with valid calibration reports shall be furnished with the bid. Manufacturer shall posses 0.1 class instruments for measurement of losses. vii. Quality Assurance Plan (QAP) with hold points for purchaser s inspection as per Annexure The successful Bidder shall within 30 days of placement of order, submit following information to the purchaser. i. List of raw materials as well as bought out accessories and the names of sub-suppliers selected from those furnished along with offer. ii. Type test certificates of the raw materials and bought out accessories The successful Bidder shall submit the routine test certificates of bought out accessories and central excise passes for raw material at the time of routine testing PACKING & FORWARDING: 25.1 The packing shall be done as per the manufacturer s standard practice. However, it should be ensured that the packing is such that, the material would not get damaged during transit by Rail / Road / Sea The making on each package shall be as per the relevant IS. Signature And seal of Bidder Page 14 of 27

15 26.0 SCHEDULE: 26.1 The tenderer shall fill in the following Schedules mentioned in Section-V which from part of the tender specification and offer. In schedule A the specific values shall be furnished and only quoting of IS reference is not sufficient. If the schedule are not submitted duly filled in with the offer, the offer shall be liable for rejection. Schedule A. Schedule B Schedule C. Guaranteed Technical Particulars Schedule of Deviations from Specification. Schedule of Tenderer s Experience All deviations from the specifications shall be brought out in the schedules of deviation (Schedules B ). The discrepancies between the specification and the catalogues, literatures and indicative drawings which are subject to change, submitted as part of the offer, shall not be considered and representation in this regard will not be entertained. If it is observed that there are deviations in the offer in G.T.P. of elsewhere other than those specified in the deviation schedule B then such deviations shall be treated as deviations For any deviation from the specification, which is not specifically brought out in the schedule of deviations, the offer may be liable for rejection. The deviation brought out in the schedule shall be supported by authentic documents, standards and clarifications; otherwise the offer may be liable for rejection. GSECL at their discretion will decide regarding acceptance of deviation The tenderer shall submit the list of orders for similar type of equipments, executed of under execution during the last three years, with full details in the schedule of Tender s experience (Schedule C ) to enable the purchaser to evaluate the tender DRAWINGS / DATA / DOCUMENTS TO BE SUBMITTED BY BIDDER ALONGWITH THE BID As a minimum, the bidder shall furnish the following in two sets failing which the bids shall be rejected. i) Typical general arrangement drawing of the equipment showing overall dimensions. ii) Typical schematic drawing in respect of equipments offered iii) Catalogues for equipment and fittings & accessories iv) Operation & Maintenance Manual. v) Schedules as per Section IV. vi) Quality assurance plan vii) Type test reports of similar rating equipment viii) Experience certificates of supply of identical types of equipment ix) List of sub-vendors for purchaser s approval DRAWINGS / DATA / DOCUMENTS TO BE SUBMITTED BY SUCCESSFUL BIDDER After issue of detailed purchase order, the successful bidder shall submit documents as mentioned in Section-V, for approval. In normal practice, the documents submitted for the approval will be commented upon or approved if in order, within 30 days from the date of receipt of the same. Date: Name : Signature. Status. Signature And seal of Bidder Page 15 of 27