Size: 10mm-630mm; Material: 10#-45#, Q345A/ B/ C/ D, 27SiMn, 40Cr, 40CrMn, 20CrMn, 30Mn Executive standard: GB8162(structural Pipe), GB8163(fluid Pipe), GB3087-99(Boiler Pipe), GB5310-95(Boiler Pipe for high pressure), GB6479-2000(fertilizer special Pipe), GB9948-88(petroleum cracked Pipe),...