... :JIS G3454-2007, JIS GB/T ... Grade: 20#, 45#16Mn, St52, St42 Carbon steel butt welded seamless pipe fitting Standard:JIS ... G3454-2007, JIS GB/T ... Grade: 20#, 45#16Mn, St52, St42 Carbon steel butt welded seamless pipe fitting details: 1 ... G3455-2005, GB/T ...Grade: 10#-45#, 16Mn, ST35-ST52, Q195-Q345Grade: 20#, 45#, 16Mn, St52, St42, Q345, Q195, ...Thickness: 6 - 30 mmSection ...