某油田集油干线弯管开裂失效原因研究

Study on the Causes of Cracking and Failure of the Elbow of the Main Oil Gathering Line in an Oil Field

通过对某油田集油干线弯管刺漏部位的化学材质分析、微观形貌观察和残余应力分析,结果表明:该管段材质的金相组织、硬度和强度不满足相应标准要求,导致管材的脆性增加,致使在缺陷位置发生裂纹起源,在局部拉伸应力、疲劳载荷及残余应力影响下,管段在裂纹处快速撕裂。

The chemical composition of puncture site of the elbow of the main oil gathering line in an oil field was analyzed,its micromorphology was observed,and its residual stress was analyzed.The results showed that the metallographic structure,hardness and strength of the pipe segment materials did not meet the requirements of the corresponding standards,resulting in the increase of the brittleness of the pipe,causing the crack origin at the defect location.Under the influence of local tensile stress,fatigue load and residual stress,the pipe segment rapid tore at crack.