20钢管化学成分与机械性能化学成分机械性能工艺性能序号牌号规格CMnSiSPCrNiCu抗拉强度屈服强度伸长率涡流探伤压扁120325*80.180.470.240.0190.0160.040.020.01475/490345/33029/30逐支合格合格/合格220325*100.170.480.250.0160.0210.040.020.01475/495340/35529/26逐支合格合格/合格320426*100.210.520.270.0210.020.040.020.02485/470320/33526/28逐支合格合格/合格