GB753948A - Improvements relating to improved mechanisms for controlling the flow of fluid through a pipeline - Google Patents

Abstract

753,948. Manually-actuated valves. ERDMAN, E. W., and LAMPARD, E. D. July 16, 1954, No. 20780/54. Class 135. A screw-actuated valve comprises a spherical valve member 38, Fig. 1, having trunnions 41, Fig. 4, engageable with surfaces 45, 46, 48, 49 on a cradle 32 in which the valve member is loosely mounted. The cradle has a flow passage 47, with slots 52 slidably engageable with guide members 43 on the valve body 10, and with a slot 36 engageable with a screw-threaded operating spindle 18. The guide members 43 are arranged so that on downward movement of the cradle their upper faces 44 engage the trunnions 41 to limit the downward movement of the valve member and position it immediately opposite a valve seat ring 42 mounted in the valve outlet passage 17 to enable the pressure fluid flowing through the valve to seat the valve member on the ring. Further downward movement of the cradle brings the surfaces 48 into engagement with the trunnions positively to hold the valve member in its seated position. To unseat the valve member, the cradle is moved upwardly until the surfaces 46 engage the trunnions to roll them into a central position between the surfaces 45, 46, and, further upward movement of the cradle, raises the valve member above the seat ring and aligns the passage 47 with the valve flow passages 14, 17. In a modification, the cradle 71, Fig. 6, is formed with a skirt portion 87 engageable with a seat ring 88 mounted in the valve inlet passage 14 to seal the upstream side of the valve as well as its downstream side. In this arrangement, should the downstream seat ring become worn, the disposition of the valve body in the flow line and of the cradle in the valve body may be reversed to position the seat ring 88 on the downstream side of the valve. Instead of being formed integral with the valve body the guide members 43 may be separate therefrom and secured to the body by the engagement of screws 94, Fig. 8, in slots 92. Gaskets 95 seal the body against leakage and screws 96 provide adjusting means.