GB692653A - Improvements in or relating to pressure reducing valves - Google Patents

Abstract

692,653. Valves. BRITISH OXYGEN CO., Ltd., BLACK, G. D., and WALSH, J. March 13, 1952 [Feb. 26, 1951], No. 4609/51. Class 135 In a pressure-reducing valve of the type in which the valve 9 is actuated by a diaphragm 3, bellows, or piston subject on one face, e.g. the upper, to outlet pressure and, on the other face, to a static loading, as by spring 4, adjustment of the static loading is effected by axial rotation of the tube 18 constituting the inlet for the high-pressure fluid. The spring 4 abuts against a diaphragm-supporting plate 22 and an abutment plate 23 in screwed engagement with the tube 18, and rotation of the tube raises or lowers the plate 23 which is prevented from rotating by the engagement of a rib 24a on the casing in a slot in the plate. A keying disc 43 fitting into a complementary recess in the valve casing and engaging in a slot in the tube 18 prevents inadvertent rotation of the tube. The high pressure fluid enters past a filter 13 and passes from the valve through bores 36 into the outlet chamber on the upper side of the diaphragm. An adjustable stop 37 prevents excessive upward movement of the diaphragm. An extension 25 of the obturator slides on the tube 18, and leakage of fluid past this extension is prevented by a bellows 27 which is secured at its lower end to an annular member and a plate 29, the annular member being sealed to the tube by a U-ring 31 of rubber. Valve outlet pressure is communicated to the interior of the bellows by a passage 32, and the bellows is protected by a skirt 33 depending from extension 25. In a modification, a stuffing box of U-shape replaces the bellows.