第三方损坏对管道可靠性的影响规律

Influence laws of third party damage on pipeline reliability

影响管道可靠性的因素众多,为了研究第三方损坏因素对管道可靠性的影响规律,结合管道遭受第三方损坏活动冲击概率和冲击力作用下管道失效概率2个方面,建立了定量计算模型。采用故障树分析方法,建立了管道第三方损坏故障树,确定影响第三方损坏活动因素的类型及逻辑计算关系,研究了故障树中基本事件概率取值方法,从而可计算管道遭受第三方损坏活动冲击的概率。在第三方损坏冲击力作用下,管道本身材料强度产生抗力,基于冲击力和抗力的相互作用,研究了穿刺失效模型和凹陷-划伤失效模型,确定了2个模型的极限状态方程,可定量计算第三方损坏对管道可靠性的影响程度。以中国某天然气管道为例,收集计算所需参数因子,计算了第三方损坏导致管道失效概率值。

The reliability of pipelines is affected by a large number of factors. In order to investigate the influence laws of third party damage factors on the reliability of pipelines, a quantitative calculation model was established by combining the impact probability caused by the third party damage and the pipeline failure probability under the effect of impact force. Then, the fault tree of third party pipeline damage was built up by means of the fault tree analysis method to determine the type and logic calculation relation of the factors that influence the third party damage activity. And the method for determining the probability of basic event in fault tree was studied to calculate the probability that the pipeline is impacted by the third party damage activity. Under the effect of the impact force caused by the third party damage, the material strength of pipe itself generates resistance. Based on the interaction between impact force and resistance, both punch-through failure model and dent-gouge failure model were studied and their limit state equations were confirmed. By virtue of the limit state equations, the influential degree of third party damage on pipeline reliability can be calculated quantitatively. Finally, a domestic natural gas pipeline was taken as an example. Its parameters which were needed for the calculation were collected and the probability of pipeline failure caused by the third party damage was calculated.