... ASME B36.10M-1996 ,API ,ANSI ,GB, SH,HG, MSS,JIS,DIN Material ASTM A106 GRB/ A53 GRB/ API 5L GRB ... / API 5 CT /Q345/A335/ST37/ST52 Packaging painting black, pipe cap, steel strips bundled. Applications range petroleum, construction ,shipbuilding,smelting, aviation ... production process are made under the ISO9001:2000 strictly. carbon steel seamless steel pipe