Shafer气液联动执行机构异常关断事故树分析

输气管道干线截断球阀的气液联动执行机构经常出现误关断的情况,严重影响了管道的安全运行和企业效益.利用事故树定量分析的方法对异常关断事故进行了系统分析.阐述了气液联动执行机构自动关断的原理,利用事故树法详细分析了造成气液联动执行机构异常关断的各种因素,并对各个因素的影响程度进行了定量计算.对可能导致异常关断的29个基本事件进行定量分析后可知：人为失误、ESD误触发、电磁阀掉电、引压管冰堵等因素是造成气液联动执行机构误关断的重要原因.事故树分析结果与管道实际运行情况一致,表明事故树分析方法在实际生产应用中是合理有效的.

Fault tree analysis on abnormal shutoff of shafer pneumatic-hydraulic actuator

The pneumatic-hydraulic actuator of shut-off ball valve on a gas trunk line is often shut off by mistake,severely influencing pipeline safety operation and enterprise economic benefits.This paper systematically analyzes the abnormal shut-off accidents using fault tree quantitative analysis method.Above all,the principle of automatic shutoff of pneumatichydraulic actuator is illustrated,then the possible factors causing abnormal shutoff of the actuator are analyzed thoroughly using fault tree method,and finally the relevant influential degree of the factors are calculated quantitatively.It is known based on the quantitative analysis of 29 basic incidents probably inducing abnormal shutoff that the main factors causing the shutoff of the pneumatic-hydraulic actuator by mistake are artificial error,ESD false triggering,power disconnection of electromagnetic valve and ice blockage of pressure pipeline,etc..Fault tree analysis results are consistent to real pipeline operation situations,indicating rationality and effectiveness of fault tree analysis method in real production and application.（1 Table,3 Figures,8 References）