... floating air balloon.C2H2≥98GB6819-1996bottle/cylinderWelding, cutting, heating, organic raw materialspropene≥99.5Q/DY-98KGWelding, ... 99GB/T7445-1995bottle/cylinder Raw material gas, high-altitude weather balloon used in chemical industry.pure ... 99 GB/T4842-95Bottle Welding shielded welding, stainless steel smelting, container, steel structure manufacture, mold processing, etc. argon for welding