HYDRAULIC DAMPING MEANS FOR HINGED CHECK VALVE,申请号GB19750044782-传众专利搜索

HYDRAULIC DAMPING MEANS FOR HINGED CHECK VALVE

申请公布号：GB1517030(A)

申请号：GB19750044782

申请日期：1975.10.29

申请公布日期：1978.07.05

申请人：

WHEATLEY CO

分类号：F16K15/03;F16K47/00;(IPC1-7):16K47/00;16K15/18

主分类号：F16K15/03

摘要：<p>1517030 Valves WHEATLEY CO 29 Oct 1975 [6 March 1975] 44782/75 Heading F2V In a hinged-clapper type check valve provided with hydraulic damping means to prevent the clapper shamming on its seat, the damping means comprise a piston 78 sliding in a cylinder 64 the chambers above and below the piston being interconnected through a valve 140 which allows substantially unrestricted flow through it as the piston rises with the check valve opening but restricts flow when the piston descends as the check valve closes. A relief valve (144), Fig. 2 (not shown), is provided in parallel with the valve 140 to relieve any excess pressure which may develop in the cylinder 64 arising from a surge of reverse flow in the check valve. The upper and lower piston-rods 80, 50 are made pressure balanced by interconnecting the chamber in which the rod ends move, by tubing (112), Fig. 2 (not shown), to which a next valve (160) is connected. A stop valve (116) allows, with vent valve (160) open, for the upper chamber 92 to be de-pressurized so allowing for a cap 96 to be removed after which a tool may be attached to the upper end of the piston-rod 80 for manual operation of the check valve. Facilities are also provided for pressurizing and recharging the hydraulic fluid in the cylinder 64. A disc 102 at the upper end of the piston-rod 80 actuates an indicator (170) to show if the check valve is open or closed. The piston 78 may have a small wheel passage through it.</p>