welded steel tube: 1) ISO 9001:2008,PED 2)OD:10-219.08mm WT:5S-40S 3)Export widely to USA, ... 1/2",3",3 1/2",4",5",6",8",10",12",14",16",18"5.W.T:SCH5S,SCH10S,SCH40S ... Composition(%)ASTMCCrNiMnPSMoSiCuN201≤0.1516.00-18.003.00-5.505.50-7.50≤0.060≤0.030 -≤1.0 -≤0.25304≤0 ... .0717.00-19.008.00-10.00≤2.00≤0.035≤0 ...