bids are invited for industrial gases maintenance and testing of gas cylinders schedule 1_ 10 m1060100280 - industrial oxygen gas 99 pure is 309 , schedule 2_20 m1060500206 - gas chem argon 99 999 gr 1 is5760 , schedule 3_ 30 m1060150203 - gas chem nitrogen 99 98 gr 1 is1747 , schedule 4_40 m1060950096 - gas chem zero air 99 999 , schedule 5_50 - hydrostatic testing of gas cylinder , schedule 6_60 - cylinder valve replacement , schedule 7_70 - spindle replacement , schedule 8_80 - gland nut replacement , schedule 9_90 - cylinder painting charges , schedule 10_100 - cylinder cap replacement , schedule 11_110 - cylinder ring replacement , schedule 12_120 - de greasing charges