... ),1Cr17Mo(434)1Cr12(403),1Cr13(410),2Cr13(420),3Cr13(420)GB/T 14976-2002GB/T 14975-2002 -Decorative Stainless Steel 4 ... )60-630×1.53-40 Rectangular TubeQ195,Q235,Q345,20#GB/T6278-2002 Structure, decoration, construction20*20-500*500 ductile iron ... water, machinery, military industryDN80-1500-square pipeQ195,Q235,Q345,20#GB/T6278-2002 Structure, decoration, construction