管道沟槽缺陷破裂强度评估方法研究

Study of Burst Strength Assessment Method of the Gouge Defect on Pipeline

管道在安装施工及运行中不可避免地会出现机械损伤,机械损伤破裂是管道的主要失效形式之一,沟槽缺陷是管道机械损伤的主要形式。国际上普遍采用NG-18公式评估管道沟槽缺陷。将各种形式的NG-18公式计算结果与试验结果进行比较,得出流变应力是影响NG-18公式预测失效应力的主要因素。采用修正后的ASME B31G标准中的Folias因子与取均值的流动应力的组合最接近实际情况,是一种比较理想的评估方法。

In the pipeline＇s construction phase and long term operation time, there will be inevitable mechanical damage in the pipeline. The burst of mechanical damage in the pipeline is the main form of pipeline failure. Gouge is the main form of mechanical damage. Commonly use NG-18 formula for assessment of pipe gouge defects in international. Comparing various forms of NG-18 formula with the experimental results, it was educed that the flow stress was a main factor of affecting the failure stress that NG-18 formula predict, and the combination of the Folias factor in the revised ASME B31G standard and the mean flow stress was proximal to the actual situation, so it is a more ideal combination.