X65MS耐酸性埋弧焊管的研制

采用低C、低Mn、微合金化设计和洁净化冶炼、控轧控冷工艺制造的X65MS耐酸性热轧卷板．通过优化焊接工艺参数、采用耐酸性焊接材料、控制焊接热输入、控制钢管成型残余应力等，开发出了X65MS耐酸性埋弧焊管，并对焊管管体和焊缝组织性能进行了研究。研究结果表明，焊管管体的屈服强度为460～465MPa，抗拉强度为555～565MPa，焊缝抗拉强度为605-610MPa，管体和焊缝的硬度均小于250HV10，0℃下母材冲击功大于230J，焊缝冲击功大于130J；按照NACE-0284标准进行HIC测试，母材、焊缝和热影响区裂纹敏感率（CSR）、裂纹长度率（CLR）和裂纹厚度率（CTR）均为零；按照NACE-0177标准进行SSCC测试，采用A溶液，在72％，80％和90％三种载荷下．均未出现断裂，管材表现出良好的力学性能和耐酸性。

Research and Development of X65MS Grade Acid Resistance Submerged Arc Welded Pipe

The X65MS acid resistance hot-rolled coil was manufactured by using the technology of low carbon,low manganese,mieroalloying design,clean smelting, controlled rolling and controlled cooling. Through the optimization of welding parameters,adopting acid resistance welding materials,controlling welding heat input,controlling residual stress of pipe forming and so on ,the X65MS acid resistance submerged arc welded pipe was developed,and the structure properties of pipe body and weld were studied. Test results showed that the yield strength of pipe body is 460-465 MPa,the tensile strength is 555-565 MPa,the tensile strength of weld is 605-610 MPa,the hardness of pipe body and weld both are less than 250HVi0. Under 0 ℃ ,the impact energy of pipe body is higher than 230 J,and the impact energy of weld is higher than 130 J. The HIC test was conducted in accordance with the N ACE-0284 standard,the cracking sensitivity rate （CSR）, crack length ratio （CLR）, crack thickness ratio（CTR） of the steel pipe,weld and heat affected zone aro all zero.The SSCC tests were carried out in accordance with N ACE-0177 standard,using A solution,under three loads of 72%, 80%and90% ,no fracture appears. The pipe is with good mechanical properties and acid resistance.