... Manufacturing standards: GB, 4) seamless steel pipe -product name-main material-standard-usessize range(mm)stainless steel pipe 0Cr18Ni9 (304),00Cr19Ni10 (304L),00Cr17Ni14MO2( ... 2002 -Decorative Stainless Steel 4-426×1-40 Structural Pipe 10,20,35,45,Q23516Mn Q345BGB/T8162-2008--for the general structure6- ... ,20#GB/T6278-2002 Structure, decoration, construction20*20- seamless steel pipe for construction