... oxygen ≥99.5GB-T3863-1995 TonSteel cutting, welding, flame processingIndustrial nitrogen ≥99.5GB-T3864-1996BottleReplacement gas and protection gas for chemical industry,metallurgy, and ... BottleElectronic industry, chemical industry, analysisDissolved acetylene ≥98GB6819-1996BottleWelding, cutting, heating, organic raw materialsCutting gas ≥99.5HG/T 3661.1-1999 Bottle Metals ...