procurement of critical spares of hydrogen generation plant installed at 2x600mw , sstpp , mppgcl , dongalia , complete suction valve & discharge valve ( for ist stage & 2nd stage ) ( 1 set means 04 nos . suction valves & 04 nos . of discharge valves ) , piston ring set ( for ist stage & 2nd stage ) ( 1 set =12 nos . ) , diaphragm ( 03 nos . for ist stage & 03 nos . for 2nd stage ) ( 1 set =06 nos . ) , complete piston ( for ist stage & 2nd stage with its connecting rod assembly ) ( 1 set =02 nos . ) , relief/unloader assembly set ( for ist stage & 2nd stage ) , oil pump , oil pressure & hydrogen pr . regulator valves , h2 side lye cooler assembly with its body , o2 side lye cooler assembly with its body , h2 side lye filter with its body , o2 side lye filter with its body