| 摘要 |
The shut-off valve has a closure plate assembly slidable across a flow duct between seal surfaces of a housing contg. the duct. The assembly comprises two plates adjacent the respective seal surfaces and a ring situated between the plates. Springs between the ring and the plates press latter against the seal surfaces. The inside of the ring serves as a cylinder for two pistons connected to the respective plates so that on introduction of pressure fluid between the pistons the plates are urged towards one another. This releases the assembly from the seal surfaces and for being slid to open the valve. |
