| 摘要 |
A flow system comprises a system flow path extending from a system inlet to a system outlet. A pressure module is provided within the system flow path to establish a differential pressure between upstream and downstream sides thereof during flow from the system inlet to the system outlet The system also comprises a valve provided within the system flow path, and a valve actuator in pressure communication with the system flow path on upstream and downstream sides of the pressure module. The valve actuator is driven by a differential pressure established by the pressure module to move between a first position in which the valve is closed, and a second position in which the valve is opened. |
