... steel pipeit is used in petroleum,chemical,electric power,boiler etc as they ... metallurgy, food, water conservancy,electric power, chemical industry,Chemical, chemical fiber, pharmaceutical machinery, etcASTM A213ASTM A312304304L316316L321steel pipe ... PIPEUsed in general structure stents, low voltage liquid transportation, etcGB/T13793-1992GB3091-2001A53A333 GR6Sprial steel ...