| 摘要 |
An emergency shut-down system to close a gate valve in a pipeline and therefore terminate flow. The closing action is initiated when a pilot valve senses pressure in the pipeline outside predetermined limits. This reduces the signal pressure in the system which, in turn, causes a fluid dump from the gate valve actuator which closes the gate valve and terminates fluid flow in the pipeline. The system is reactivated by manually pumping the system which re-opens the gate valve and allows fluid flow in the pipeline to again continue. |
