X65煤层气焊管变形开裂原因分析

Analysis on Deformation and Cracking of X65 Coalbed Methane Welded Pipe

在检修现场发现X65煤层气焊管存在非正常变形量及裂纹。本文通过化学分析、力学性能检测、金相分析、仪器化压痕法检验等方法进行了分析,经过排除法论证和现场确认,由于直缝焊管的抗拉强度比螺旋焊管的抗拉强度高,山体滑坡造成施工现场公路填方土蠕动变形,蠕动变形对公路附近管道造成巨大轴向推力,当此轴向外力超过管道本身的屈曲载荷时,进而造成管道失稳变形。

Abnormal deformation and cracks of X65 coalbed methane welded pipe were found in the maintenance site. This paper analyzes them through chemical analysis, mechanical property test, metallographic analysis, instrumented indentation test and other methods. After elimination method demonstration and field confirmation, the tensile strength of straight welded pipe is higher than that of spiral welded pipe, landslides cause creep deformation of highway filling soil in the construction site. Creep deformation causes huge axial thrust on the pipeline near the highway. When the axial external force exceeds the buckling load of the pipeline itself, it will cause instability deformation of the pipeline.