1) closed center pilot control valve

中位关闭先导控制阀
2) closed center pilot valve

中位关闭先导阀
3) pilot center valve

先导中位阀
4) pilot control valve

先导控制阀
5) pilot valve plunger control position

先导阀柱塞控制位置
6) limit/shutdown pilot valve

限位/关断先导阀
参考词条