| 摘要 |
<p>A flow control valve assembly for closing an inlet into a housing through which powdery or granular material is flowing and for sealing said inlet once closed, the assembly comprising a closure member movable within the housing from an inoperative position in which the inlet is open into a normal operative position closing said inlet, during which movement a deformable sealing ring mounted in the housing to surround the inlet wipes over, to clean, the closing surface of the closure member and to make initial sealing contact with the closure member. Inflation of the sealing ring against the closure member in its normal operative position then supplements the seal while, on subsequent pressurisation of the interior of the housing, the closure member is displaced bodily within the housing axially towards the inlet to make increased contact with, to supplement further the seal with, the sealing ring. 1.</p> |
