管道气直驱执行机构在天然气长输管道工程的应用研究

在天然气输气管道工程中,紧急切断阀通常选用气液联动执行机构,但其结构复杂、价格昂贵;紧急放空阀常采用电动执行机构,但其在安全性方面存在不足。因此,有必要为安全仪表系统(SIS)阀寻找满足功能安全、结构简单并节省投资的其他类型执行机构。通过与气液联动执行机构、电液联动执行机构、气动执行机构及电动执行机构的性能和经济性比较,介绍了管道气直驱执行机构和其他类型执行机构的适用场合,并阐述了管道气直驱执行机构的概念、分类和应用情况。通过分析,得出了对于天然气管道工程中口径16英寸(1英寸=25.4 mm)或16英寸以下的紧急切断阀,管道气直驱执行机构更为适用的结论。这为以后的天然气长输管道工程中执行机构类型选择提供了参考和指导。

Application of Pipeline Gas Direct-Driven Actuator in Natural Gas Long Distance Transmission Pipeline Project

In natural gas transmission pipeline project,pneumatic-hydraulic actuator is commonly used for emergency shut-off valve,but it is complicated and expensive,and electric actuator is often used for emergency vent valve,however it has defects in safety.Therefore,it is necessary to find other types of actuators for the safety instrument system(SIS)valves,that satisfy the requirements of functional safety,simple structure and saving on investment.By comparing the performance and economical efficiency of pneumatic-hydraulic actuator,electrohydraulic actuator,pneumatic actuator and electric actuator with that of the pipeline gas direct-driven actuator,the applicable occasions of the pipeline gas direct-driven actuator and other types of actuator were described,and the concept,classification and application of the pipeline gas direct-driven actuator were expounded.Through analysis,it was concluded that the pipeline gas direct-driven actuator was more suitable for the emergency shutoff valve of 16"(1 inch=25.4 mm)or below in the natural gas pipeline project,which could be used as reference for actuator selection in the future natural gas long-distance pipeline project.