20#无缝钢管化学成分：
碳 C ：0.17%～0.2% 硅 Si：0.17%～0.37% 锰 Mn：0.35%～0.65% 硫 S ：≤0.035% 磷 P ：≤0.035% 铬 Cr：≤0.25% 镍 Ni：≤0.25% 铜 Cu：≤0.25%
20#无缝钢管为低碳钢管，执行标准：GB/T8162-2008 GB/T8163-2008 GB3087-2008 GB9948-2013 GB6479-2013

20#无缝钢管45×3.5-4-5-6-7-8-9
20#无缝钢管48×3.5-4-5-6-7-8-9-10
20#无缝钢管51×3.5-4-5-6-7-8-9-10
20#无缝钢管56×3.5-4-5-6-7-8-9-10
20#无缝钢管57×3.5-5-6-7-8-9-10-12
20#无缝钢管60×3.5-4.5-5-6-7-8-9-12-14
20#无缝钢管63×3.5-4.5-5-6-7-8-9-10-12-14
20#无缝钢管68×4-4.5-5-6-7-8-9-10-12-14-16
20#无缝钢管70×4-4.5-5-6-7-8-9-10-12-15-16
20#无缝钢管73×4-4.5-5-6-7-8-9-10-12-15
20#无缝钢管76×4-4.5-5-6-7-8-9-10-12-14