BOG增压机304L管线开裂失效分析

Cracking Failure Analysis of 304L Pipeline in BOG Compressor

采用光学显微镜、扫描电镜对BOG增压机304L管线失效断口形貌进行观察,并结合理化试验结果分析了BOG增压机管线开裂失效的原因。结果表明：焊接接头填充金属量多,焊接停留时间长,焊接部位热输入量过大,导致在主管上形成了焊接热裂纹,并在增压机工作时振动的影响下开裂失效。建议提高接头尺寸精度,减小热输入,焊后进行表面无损检测,确保无焊接热裂纹。

The morphologies of failure fracture of 304 L pipeline in BOG compressor were observed by using optical microscope and scanning electron microscope, and the cause of cracking failure of BOG compressor＇s pipeline was analyzed combined with the physical and chemical test results. The results show that the amount of filler metal in welded joint is large,the welding dwell time is long and the heat input in welding position is excessive, which causes the formation of welding hot crack in the main pipe. The cracking failure occurs under the influence of the vibration of the comperssor. It is suggested that dimension accuracy of the joint be improved, the heat input be reduced and surface nondestructive testing be carried out after welding to ensure no welding hot cracks.