procurement of most critical spares for instrument and service air compressor make kirloskar model t-btd-pm of unit no 1 and 2 ph-i at sgtps mppgcl birsinghpur , cross head guide , cross head guide cover , lp piston ring , lp valve spring ( suction ) , lp piston ring & rod assembly , lp sealing ring , lp valve covers o-ring ( suc . ) , lp unloader o-ring ( out . ) , lp cross head nut , lp suction valve stud with hole m16x1 . 5x80l , packing for crank case top cover , conn . rod & cap assembly , cylindrical pin ( lp suc . ) , hp valve guard ( dis . ) , hp piston ring , hp piston guide ring , hp unloader o-ring , hp o-ring suction , hp o-ring discharge , hp valve bolt , hp suction unloader assembly , hp . valve pusher assembly , hp valve spring dis . , bush for one way clutch , gudgeon pin cover , one way clutch assembly , gudgeon pin , motor pulley , gear oil pump , lp guide ring , cross head assembly , oil scraper , oil wiper ring