| 摘要 |
<p>1483127 Valves CROSBY VALVE & GAGE CO 7 Jan 1975 [4 Feb 1974] 567/75 Heading F2V A relief valve has inlet and outlet passages 14, 16; a seat member 20; a sleeve 44 coaxial with the passage through the seat member and having an axially adjustable guide ring 54 extending thereof with ports 56 through the guide ring to the outlet passage; a valve head 28 slidable in the sleeve, with a disc 22 to close upon the seat member; there being a chamber 68 above the valve head enclosed by a piston 70; and a passage 60, between the sleeve 44 and guide ring, with a constriction 64 leading to the ports 56. A second passage 58 may be formed between the tapering outer surface of the valve head 28 and the inner surface of the guide, to lead to a chamber 66 from which fluid passes via apertures 50 and channels 48 between the sleeve and valve head to chamber 68 when the valve is fully lifted. The valve described is loaded by a spring 34 through a spindle 32 sealed by a labyrinth 72 on piston 70. A nozzle ring 24 may adjustably extend from the seat member towards the valve head. At the set pressure fluid escaping through the small seating opening is deflected by the nozzle ring to the surface 30 of the valve head and by the guide ring to chamber 58 thus producing additional lifting force and rapid valve opening. With the valve open and a flow established through passages 58, 60, fluid below passage pressure is applied to chambers 66, 68 which assists in providing rapid closing.</p> |
