摘要 |
<p>A valve for sealing off pressurized fluid for an extended period comprises, a body defining a passageway, a closure member in said passageway for closing off the latter against fluid flow, a pivotally mounted arm for maintaining the closure member in its passageway closing off condition, and a catch for releasably retaining the arm in the valve closed position. In one arrangement, the closure member includes a diaphragm which extends across and divides the passageway and is arranged to burst under a sufficient pressure differential, the arm carrying a backing plate which, in its valve closed position is superimpositioned against one face of the diaphragm to prevent it from bursting.</p> |