... Name Seamless Steel Tubes for Boiler, Pressure Vessel & Heat ExchangerAmerican Standard ASTM A53,ASTM A106,ASTM A333,ASTM A334 ... B GRA,B, C; GR1,GR6; GR.A-1,GR.CChinese Standard GB 3087,GB 5310,GB 6479, ... 8,St45.8,17Mn4,15Mo3,13CrMo44British standard BS 3059-1,BS 3059-2,Grade 320,360,440,243Japan ... 410,STB510,STB A12,STB A22European Standard EN 10216-1, EN 10216-2Grade P235TR1, P235GH, P265GH etc.Size ...