不同温度下两种管材应力应变特性的研究

通过对国产Ｘ６０螺旋埋弧焊管（ＳＳＡＷ）和进口Ｘ５２直缝电阻焊管（ＥＲＷ）的温度拉伸试验，研究了两种钢管母材和焊缝的应力应变特性。试验结果表明，两种焊管的屈服强度和抗拉强度随温度的降低而提高，断后伸长率、最大均匀变形断面收缩率、断后断面收缩率以及屈强比随温度降低而降低；两种焊管母材应力应变曲线特征为连续屈服，而焊缝为非连续屈服，存在明显物理屈服现象；Ｘ６０ＳＳＡＷ焊管母材与焊缝强度基本相当，Ｘ５２

Study on Stress-Strain Behavior of X60 SSAW and ERW X52 Line Pipes

Tension tests under different temperatures were conducted for X60 SSAW and X52 ERW line pipes. The results indicate that the strength of both pipes increased as test temperature dropped, the plasticity dropped as test temperature decreased. The shape of stress-strain curves of both base metals was continuous yielding, while that of both welds was non-continuous yielding and presented apparent physical yielding. As to X60 SSAW pipes, the strength of base metal and weld was almost the same, but a big difference was found between the base metal and weld of X52 ERW pipes. During oil and gas pipeline design and safety assessment,emphasis should be put on stress-strain behavior of pipe metals under different temperatures and difference of stress and strain behavior between base metal and weld.