| 摘要 |
<p>A shut-off device, such as a valve or a cock, for pipelines and comprising a casing provided with a flow passageway. The casing is provided with an inlet and an outlet and at least one shut-off member provided with a cavity, the member being movable between a position in which the flow passageway is open and a position in which the flow passageway is closed. An auxiliary chamber is arranged in the casing and communicates with the cavity of the shut-off member. The auxiliary chamber is defined by a separate, almost non-resilient wall portion abutting an abutment face on the wall of the casing. A pressure-relieving passageway formed in the wall of the casing is arranged between an abutment face at the auxiliary chamber and the inlet or outlet of the shut-off device. As a result, a shut-off device having more simple structure than known shut-off devices is obtained.</p> |
