SAFETY EMERGENCY VALVE Russian patent published in 2003 - IPC

FIELD: safety valves of plunger type designed for protection of head ends of powered support hydraulically operated props at dynamic loads of enclosing rocks. SUBSTANCE: valve includes body, cylindrical plunger with central channel, packing ring, self-adjusting washer and spring. It is provided with sleeve having seals and installed in axial bore of body and separating cavities of high and low pressure, and slide valve with axial channel and radial holes located in several rows. Cylindrical plunger is of varying diameter in several rows. Cylindrical plunger is of varying diameter with several rows of radial holes. Secured to cylindrical plunger part with large diameter is slide valve for engagement with spring installed between sleeve and slide valve shoulder. Slide valve diameter exceeds that of cylindrical plunger. EFFECT: higher capacity of safety valve. 2 dwg