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%

力学性能:

                                  抗拉强度 σb (MPa):≥410(42)

                                  屈服强度σs (MPa):≥245(25)

                                  伸长率 δ (%):≥25

                                  断面收缩率 ψ (%):≥5

                                  硬度 :未热处理,≤156HB

                                  试样尺寸:试样尺寸25mm

热处理规范及金相组织:

                                  热处理规范:正火,910℃,空冷。

                                  金相组织:铁素体+珠光体。

交货状态:以不热处理或热处理(退火、正火或高温回火)状态交货。要求热处理状态交货的应在合同中注明，未注明者按不热处理交货。