每班一次用手动舵检查自动舵。
This allows the connection to be made without a wrench, using a nut equipped with a hand wheel.这使得不用扳手,而是使用带手轮的螺母就可以进行连接。
Valves with this option have a hand wheel mounted on top of the actuator for manual valve operation.配置这种备选件的阀门在执行器顶部安装一个手轮用于手动阀门操作。