X80直缝埋弧焊管制管前后拉伸性能的变化

通过对X80 级?准1 016 mm × 18.4 mm直缝埋弧焊管制管前后拉伸性能变化的研究，得出了其制管前后拉伸性能变化的一般规律。结合直缝埋弧焊管的制管过程分析认为，成型和扩径是制管前后拉伸性能变化的主要原因。对于X80直缝埋弧焊管，当扩径率为0.8%～1.2%时，既保证了钢管外观尺寸精度，又很好地控制了扩径后钢管的屈服强度和屈强比的上升幅度。扩径工艺后，钢管的屈服强度和抗拉强度都有所增加，且屈服强度的增加幅度要大于抗拉强度的增加幅度。

Study on the Tensile Property Before and After Forming of X80 SAWL Pipe

The general change rule of the tensile property of X80 Ф 1 016 mm×18.4 mm SAWL pipe before and after forming was studied.In combination with SAWL pipe manufacture,it considered that the forming and expansion are the main reasons caused tensile property change before and after forming.For X80 SAWL pipe,when the expansion rate is within 0.8%～1.2%,not only the dimensional precision of steel pipe is ensured,but also the increase range of yield strength and Y/T ratio of pipe after expansion is properly controlled.Moreover,both yield strength and tensile strength are increased after expansion,and the increase range of yield strength is greater than that of tensile strength.