海底管线钢焊接接头的安全评定及寿命预测

Safe Assessment and Life Prediction of weld in Offshore pipeline

本研究在给定裂纹尺寸和载荷条件下，根据CTOD（裂纹尖端张开位移）试验结果，采用欧共体提出的结构完整性评定方法SINTAP（Structural Integrity Assessment Procedure），针对API5LX65管线钢焊接接头焊趾处的表面裂纹进行评定。根据拉伸试验结果，建立了X65管线钢焊接接头焊缝和母材的一级、三级评定曲线。评定结果表明，不论是采用一级或是三级评定，各评定点均在评定曲线定义的范围内，说明该结构是安全的。并根据上述评定结果对结构进行疲劳寿命估算，具有实际的工程意义和经济价值。

According to the CTOD （Crack Tip Opening Displacement） test result and using the SIN-TAP （Structural Integrity Assessment Procedure） sponsored by the European Commission, crack size and load is given, and the assessment is carried out on surface flaw at the toe of weld in API 5LX65 pipeline. Based on the tensile test results of base metal and weld metal, the assessment diagram of Level One and Level Three is created. The assessment results indicate that all the assessment points are within the regions defined on the failure assessment diagrams using both Level One and Level Three, so the structure is safe. And the fatigue life is calculated in accordance with the above assessment. The research performed in this paper has significant value for both engineering and economy