tender for rate contract for supply of sf 6 gas and 3 more items.-sf6 gas (>99.7% pure) with cylinder as per product standard sg10409 rev 00, each cylinder is of capacity 50 kg of sf6 gas at ντρ. refilling of sf6 gas (>99.7% pure) in cylinder as per product standard sg10409 rev 00, each cylinder is of capacity 50 kg of sf6 gas at ntp. empty cylinder will be provided by bhel on returnable basis. ultra high pure helium gas, grade vi as per is 15583, >99.999% pure, gas volume:7 cum/cylindergas pressure: 140-150 kg/cm2 & s per product standard sg10416 rev 00.packing shall be 7 cubic meter compressed in party owned gas cylinder as per attached sg10416-002 specification. refilling of ultra high pure helium gas, grade vi as per is 15583, >99.999% pure in cylinder as per product standard sg10416-002 rev 00. empty cylinder will be provided by bhel on returnable basis.