... -18mm 3.Length:3-13m4.Material:Q195, Q235A, Q235B, Q345, ASTM A53/106, ASTMA500, ST375.Standards:GB/T3091-2001, GB/T9711 ... , and the steel pipes can be supplied according to GB, ASTM, API, DIN, JIS standards, the factory is locating in \Development ...