bids are invited for operation and maintenance power house / power plant - 6409123 - preventive maintenance of expansion tank and its gauge glass , checking , attending abnormal h2 gas leakage in 5x200mw generators and its associated pipings and h2 gas coolers. , preventive maintenance of 15.75kv bus duct inside t.g.hall: , changing excitation polarity in all 5x200mw units , preventive maintenance of slip ring carbon brushes, brush holder, neutral grounding transformer and reactor in 5x200mw units , dismantling and replacement of brush rocker assembly of slip ring for testing of rotor and remounting , preventive maintenance of earthing transformer and neutral grounding reactors of 5x200mw units , isolation of 15.75kv bus duct outside t.g. hall from man hole near a axis wall for identification of stator ef: , preventive maintenance of seal oil filters, stator water filter, valves,h2 gas driers etc , attending leakage of oil from ac dc seal oil pumps including replacement of seal if required. , preventive maintenance and greasing of bearings in a.c. seal oil pump in 5x200mw units , preventive maintenance & hydraulic testing of h2 gas coolers. , preventive maintenance and hydraulic testing of seal oil coolers in 5x200mw units , decoupling, removal, remounting alignment and coupling of ac dc seal oil pumps , preventive cleaning work of 15.75 kv duct at 4 meter. , reconditioning of all six no. 15.75kv bus duct perplex containers in 5x200mw units. , h2 gas purging and recharging , monitoring and maintaining the level of hydraulic seal oil tank , normalizing seal oil system and draining oil from gen. casing and hydraulic seal oil tank round the clock in emergency. , filling h2 gas cylinders in generator casing of 5x200mw units , bus separation from generator of all the three phases three neutrals, cleaning of seal off bushing , cleaning replacement of flexible links of phase neutral side of generator terminal as per scope of work , work on seal oil stator water coller of 200mw unit as per scope of work , replacement of defective generator hydrogen gas cooler as per per scope of work , replacement of defective float valve of seal oil tank of as per scope of work , replace valve nb 08 15 , replace valve nb 100 , replace valve nb 25 50 , replace valve pres reg , repairing brass nozz h2 co2 , servicing ac dc seal oil pumps , replace bearing sop sos , replacement of defective float valve of expansion tank of as per scope of work , to fro transportation of filled and empty hydrogen gas , to fro transportation of more than 100 nos. filled empty hydrogen gas and carbon-di-oxide gas cylinders in emergency (during odd hours) , preventive maintenance of gt cooling control cabinet, uata , b mb etc. , preventive maintenance of pt cubical: , preventive maintenance of stator water panel. , preventive maintenance of seal oil panel. , preventive maintenance of generator relay panel. , work on sp bus ducts of gt uat genreator , breakdown maintenance of thyristor cooling fan excitation transformer cooling fan , dummy load testing in excitation system. , repair ac stabilizer at excitation room , repairing of field breaker trip coil. , preventive maintenance of field breaker , preventive main excitation cooling equip , preventive main thy. excitaion reg panel , dismantling of aux contact block assy