Annexture-II Scope of Work and Other Terms Conditions Sl. 1. Removal Disconnection (i) Removal of existing heating elements, insulation brickwork of the side walls, roof, the doors and the bogie hearth. (ii) Disconnection and Removal of all old electrical cables and control cabinets 2. Repair 2.1 Furance Shell Repair : (i) Necessary repair of the furnace shell will be carried out before commencing new insulation work. 2.2 Repair alignment of both the doors of the furnace : (te : Party shall examine the condition of the door sealing / door alignment before submitting their offer.) (i) Both the doors are misaligned with the frame of the furnace. For this, plates, ribs, fixing bolts etc. are required be reset, re-adjusted and realigned. Whatever work is required achieve this objective shall be in the scope of the Party (ii) Re-Setting / balancing of counter-weight after the installation of new insulation system on the doors 2.3 Repair of Bogie : (i) Welding of steel plates wherever guide plates have broken off or rn away due constant use over the years (ii) Straightening and aligning of Bogie guide plates (iii) Straightening and repair of chain links of the Bogie hearth driving chain. iv) Overhauling of the bogie drive system including cleaning, greasing/lubrication
3. Painting: The furnace shall be painted in heat resistant silver aluminum oxide paint from the outside. 4. Installation (i) Installation of all supplied insulating materials on the walls, doors, and the roof shall be done by the Party (ii) Installation and masonry of all required and supplied refracry on bogie hearth, and the botm portion of the side walls (iii) Zone wise installation of all supplied heater elements on side walls, doors, and the bogie hearth (ii) Installation of all supplied Electrical items, instrumentation and controls 5. Connections : (i) Laying of all required power cables control wires (ii) Compensating cables of thermocouples shall be laid from the furnace temperature control instruments and the digital recorder. These cables preferably shall not have any joint in-between and if required, should be connected/terminated with appropriate K-type compatible plugs and sockets which should not interfere with the signal strength. (iii) Compensating cables of thermocouples for job temperature measurement shall be suitably terminated in a especially constructed enclosure at the bogie itself at operar side end with plug socket arrangement. (ii) Inter-connection of all electrical components 6. Resration of Existing Cooling system : In the lower part of chamber s side walls, there are uniformly arranged windows which by means of ducts laid in the lining are connected the air-inlet boxes, arranged along the side walls. Each of the boxes is connected a fan with a mor (10kW, 1500 rpm). Air circulation through the furnace is carried out downwards. On the side of inlet in front of the fans, there are two additional dampers which allow mixing of hot air exhaust from
the furnace and fresh air from the shop during cooling period. 6.1 Overhauling of both the blower fans and their operationalising and fitting with new V-belts 6.2 Resration and Overhauling of air duct system including installation of new insulation of air duct walls. specify new insulation details for air duct walls 6.3 Vents available on both the side walls of the furnace which are presently blocked shall be opened and resred and made operational for cooling 6.4 Retrofitting of pneumatically-operated dampers for controlling and mixing of furnace hot air with cold outside air (i) Two dampers (referred above at para 6) for each fan on both sides of the furnace are manually operated at present. These are be aumated through a new pneumatic system comprising of pneumatic cylinders, suitable pneumatic valves / pipes /filters etc. (ii) All the modification in dampers / new design / new dampers shall be in the scope of vendor (iii) Control of valves shall be through a Siemens PLC. PLC shall take temperature signal input from the master controller actuate pressure valves for adjusting the dampers (iv) Compressed air available at the shop floor at a pressure of about 4 bar shall be utilized for pneumatic operation of the dampers. 6.5 Overhauling of existing air vent system comprising of six holes with movable plugs designed for fresh air inlet placed at the roof of the furnace. These plugs are opened by means of manually-operated winches. (i) (ii) All the six vents shall be made leak proof by providing proper insulation around the periphery of the plug plate. Manual winches used operate the vents shall be overhauled and made operational. 6.6 Controlled cooling at the rate of 50 ºC/hr. is be achieved bring down the temperature of the furnace 150 ºC. Below this temperature, natural cooling of the job shall take place.
7. Commissioning of following items shall be carried out: (i) Thyrisrised controllers of each zone (ii) Master Temperature controller (iii) Slave Temperature controller of each zone (iv) Over Temperature controller of each zone (v) Temperature Recorders (vi) Furnace Cooling system (vii) Bogie Hearth Movement (viii) Doors lifting 8. Safety Interlocks Protection: (i) Bogie shall not be moved unless the doors are fully open. (ii) Bogie shall not be moved unless the compensation cables of thermocouples for the job temperature measurement are disconnected from their bogie junction box. (iii) Doors shall not be lifted unless heating elements are switched OFF (iv) Doors shall be operated only when the bogie is fully inside. (v) The furnace heating operation shall be interlocked with the Door operation so that heaters cannot be switched on unless the Bogie is completely inside and the doors are closed. However, a keyswitch inside the electrical cabinet shall be provided by-pass this interlocking for the use of maintenance personnel. (vi) The temperature controller shall have broken thermocouple feature so that the controller shall sp functioning and give alarm (Visible) in case of thermocouple failure. (vii) Over Temperature controller should switch Off the power supply heating elements of its zone in case of failure/breakdown of the respective Master/Slave controller (viii) All mors should be provided with thermal overload relays along with single phase preventing device. (ix) Safety of chart recorder shall be ensured in the event of electrical short circuiting of the job temperature thermocouple(s). As per furnace requirement 9. Alarm Annunciation
In the event of fault condition viz. broken thermocouple, over temperature or mor failure, an audio visual alarm annunciation system comprising a hooter and indication lamps should get activated. Three-tiered wer lamps as supplied vide Para 5./viii. of the scope of supply shall be installed at a suitable place on the furnace shell for convenient visibility. 10. MISCELLANEOUS WORKS: Supplier shall execute any other work found necessary complete the work but not stated explicitly above, along with all required material without any obligation. 11. ACCEPTANCE CRITERIA: Acceptance shall be at BHEL, Hardwar works after successful commissioning, testing and job proving and after achieving following criteria: (i) All furnace functions including sub-systems shall be demonstrated. Heating cycle for stress-relieving of two batches of fabricated components (decided by production deptt of BHEL) shall be established by heating the furnace load and temperature specifications. Rate of rise of temperature and cooling shall be ensured and demonstrated as per the tender specifications. (ii) Uniformity of the temperature of the jobs shall be within ± 5ºC. The same shall be ensured and demonstrated as part of Acceptance Criteria. 12. Down time of the Furnace shall intimate the tal downtime of the furnace required complete all the works as specified in the scope of work. However tal down time shall not exceed 60 days. An activity chart shall be submitted by the vendor detailing all the activities scheduled and time taken complete these. specify 13. Warranty :
shall stand warranty for all the materials supplied, all services provided and all the work executed for a period of 18 months from the date of successful commissioning of the furnace at BHEL, Hardwar 14. s obligation: (i) s shall visit the site, study the furnace and hold technical discussions with BHEL before submitting their bids. (ii) Any Material or work not specified in scope of supply/scope of work but required for successful modernization of the furnace may be advised and quoted by the Party along with their bid. changes shall be permissible after the placement of P.O. by BHEL and the same shall have supplied and commissioned free of cost. (iii) Party shall bring all required ols (power as well as hand ols), Meters and testing equipment as required for installation and commissioning. (iv) Party s experts shall be available at the site for a period of two weeks supervise independent operation of the furnace after the successful ance of the refurbished furnace. (v) All Welding rods and man power required for welding shall be party s responsibility. 15. BHEL's obligation: (i) Crane facility and lifting tackles like slings, rope, D-Shackles shall be provided free of cost. (ii) Electricity, welding set, Gas cutting equipment, Gases and holders shall be provided free of cost. (iii) Machining facility required for erection commissioning, subject the extent available in BHEL, shall be provided free of cost (iv) All civil work (except refracry works) shall be executed by BHEL subject prior intimation and drawing submission by the party. 16. Training : Party shall impart training on the new systems supplied and commissioned by them in situ BHEL technical staff, in following areas
(i) (ii) (iii) Instrumentation : For commissioning maintenance of Digital chartless recorders, Master and Slave temperature controllers Electrical and Electronics : For commissioning maintenance of Thyrisr controllers, PLC and control system Operation : For programming of temperature control for stress relieving of the fabricated components on the Master Temp. Controller, viewing and taking uploads of the reports and data from the digital chartless recorders, archiving of reports, printing of graphs on the laser printer and overall operation of the refurbished furnace. 17. PRE-DESPATCH INSTRUCTIONS Before despatch of the material, Party shall submit the Bill of Materials (BoM) BHEL. Only after clearance from BHEL, shall the Party despatch the material. BoM shall be sent sufficiently in advance of the delivery date so as enable BHEL study the same and comment. 18. QUALIFYING CONDITIONS 18.1 Only those vendors, who have supplied and commissioned at least one electrically heated chamber Bogie Hearth Furnace ( of minimum 400 KW capacity) with inside working volume of minimum 40 cubic meter with Insulation (ceramic fibre blankets/modules or vacuum formed boards or both), Heating Elements, Control instrumentation, Thyrisr/IGBT controllers, door trolley movement mechanisms for applications of stress relieving of fabricated components / casings in the past ten years (on the date of opening of tender) and such furnace is presently working satisfacrily for more than six months after commissioning (on the date of opening of tender ), should quote. OR Only those vendors, who have successfully revamped and modernized at least one electrically heated chamber Bogie Hearth Furnace ( of minimum 400 KW capacity) with inside working volume of minimum 40 cubic meter with Insulation (ceramic fibre blankets/modules or vacuum formed boards or both), Heating Elements, Control instrumentation, Thyrisr/IGBT-controllers, repair of Door trolley
movement mechanisms for applications of stress relieving of fabricated components / casings in the past ten years (on the date of opening of tender) and such furnace is presently working satisfacrily for more than six months after commissioning (on the date of opening of tender), should quote. 18.2 The following information should be submitted by the vendor about the companies where similar furnaces have been supplied or revamping work carried out. This is required from the vendor for qualification of the offer. (i) Name of the cusmer / company where furnace is installed/ revamped. (ii) Complete postal address of the cusmer. (iii) Month Year of commissioning. (iv) Broad specifications of the furnace(s) supplied (i.e., Chamber Size LxWxH, Payload, kw rating, Maximum temp.) and its application. (v) Name, designation, Phone, FAX no. and e-mail address of the contact person of the cusmer. (vi) Performance certificate from the cusmers regarding satisfacry performance of furnace supplied them (Original Certificate or through E-mail directly from the cusmer). The original performance certificate may be returned after verification by BHEL, if required. te: BHEL reserves the right verify information submitted by vendor. In case the information is found be false / incorrect, the offer shall be rejected.