overhaul of process air compressor k421 ( make kobe steel , model vss805 and vs407 ) in ammonia complex-fact-uc , overhaul process air compressor-k421-ac . , dismantling and refixing of oil inlet , air vent lines , balancing lines etc . associated with the compressor , dismantling and refixing of the coupling guards of both the machines . , dismantling and refixing of the diaphragm coupling from lpc-hpc and lpc-turbine . , lp compressor dis-assembly . , hp compressor dis-assembly . , cleaning and dp test on the rotor assembly and casing . , dismantling and refixing of diaphragm from the hp side compressor . , replacing the j-seals in the rotor assembly . , assembly of lp compressor . , assembly of hp compressor . , alignment of compressors to the turbine . , assistance for commissioning of the compressors . , supply of unskilled labour from the contract labour unions of fact .