基于部分行程测试法的在役电动阀设计与改造

The Design and Modification of the Electric Valve in Service Based on the Method of Partial Stroke Testing

天然气输气站场安全完整性等级(SIL等级)受限于执行器。基于功能安全理论,对分输出站电动阀,将ESD全开全关动作测试改成部分行程测试,为实现其功能做以下改造:阀门电动执行机构内增加比例控制器,将其改造成可以控制开度的阀门;安装一个机械设备去限制阀门的开度,用专门的钥匙开关将机械限制设备的销子处于设定位置;增加在线检测和故障诊断通信,通过可视的故障诊断报警确保ESD阀门的有效性。

The safety integrity level（SIL level） of a gas pipeline station is limited to the actuator. Based on the theory of functional safety, electric valves in a gas distributing station will replace an ESD full open/closed action test with a partial stroke test. And to achieve its function we do the following transformation ： an electric actuator installs a proportional controller, with which can control the open degree of the valve; a mechanical device, which can set mechanical limit pins to the setting position using a special key switch, can limit the degree of the valve; by way of the online detection and fault diagnosis of communication, the visual troubleshooting alarm can ensure the effectiveness of ESD valves.