海底管道通球风险故障树定量分析

Quantitative analysis on failure tree of subsea pipeline pigging risk

通球检测是海底管道日常运维的重要手段,但我国目前多数海底管道通球检测的执行风险较高,发生清管球卡球是最普遍的通球风险事件,为了合理规避通球风险,有必要进行作业前风险分析。将故障树定量分析方法应用于海底管道通球风险评价,通过风险辨识给出了引发卡球的各类中间事件及基本事件,绘制了海底管道通球失效故障树图,并进一步对最小割集及基本事件结构重要度进行求取。在此基础上给出了通球风险模糊综合评价数学模型及二级评价的求解过程,通过实例运算最终得出通球失效概率等级,解决了海底管道通球风险定量评价的难题,对海底管道其他类型作业风险的量化分析具有借鉴意义。

The pigging test is an important means for daily operation and maintenance of subsea pipelines. However, most of the current subsea pipeline pigging tests in China involve high execution risks, the most common one being the jamming of pigging balls. In order to reasonably guard against pigging risks, it is necessary to carry out pre-pigging risk analysis. The quantitative analysis of failure tree is applied for risk assessment in this paper. Through risk identification, various intermediate or basic events causing pig sticking were presented, and the failure tree of subsea pipeline pigging was mapped. Furthermore, the minimum cutset and the structural importance of basic events were worked out. On this basis, the resolution processes of mathematical model of fuzzy comprehensive evaluation on pigging risk and level-2 evaluation were given. Through calculation of examples, the level of pigging failure probability was worked out, helping to address the difficulties in quantitative risk assessment of subsea pipeline pigging. The research results can serve as a reference for quantitative analysis on other kinds of operation risks of sub sea pipeline.