... nitrogen ≥99.5GB-T3864-1996BottleReplacement gas and protection gas for chemical industry,metallurgy, and electric industry.Pure nitrogen ≥99.996GB ... ≥98GB6819-1996BottleWelding, cutting, heating, organic raw materialsCutting gas ≥99.5HG/T 3661.1-1999 Bottle Metals cutting ... , heating, correcting the deformation,heat treatment and the other flame processingpropylene ≥99.5Q/DY-98KgWelding ...