直径800壁厚80无缝钢管

1、2252833235445555665775825壁厚0405060811214151618222252833235445555665参考资料国家标准,GB#47T81621999,结构用无缝钢管。2、焊接钢管种类很多,比如DN25壁厚32mmDN32壁厚35mmDN40壁厚35mmDN50壁厚38mmDN...