Abstract: A safety valve for relieving excessive pressure in a fluid system including a valve body having a central chamber, a discharge flow nozzle connected into the chamber having a valve seat on the end of the flow nozzle in the chamber, a valve disc movably mounted in the chamber for movement between a closed position on the nozzle seat and an open position spaced from the nozzle seat, a valve disc holder connected with the valve disc having a deflecting rim circumscribing the valve disc seat provided with an internal outwardly divergent annular deflecting surface, a blowdown ring mounted on the nozzle having an inner ring portion provided with an outer frustoconical deflecting surface substantially parallel with and spaced from the valve disc holder deflecting surface, the blowdown ring including an outer cylindrical rim provided with circumferentially spaced semi-elliptical discharge ports and an internal cylindrical surface substantially parallel with and spaced from the outer cylindrical surface of the valve d

Abstract: An impact resistant pressure operated relief valve comprising a valve body having an exhaust port and a nozzle assembly having a flow passage which terminates in an opening surrounded by an annular valve seat. A disc holder in the valve body is slidably disposed between a closed position abuting the valve seat, thus closing the nozzle passage and a second position in which the disc holder is displaced from the valve seat, thus opening the valve port to the nozzle passage. A compression spring forces the disc holder to the normally closed position. The lower portion of the disc holder is provided with a valve disc having a facing surface which is adapted to contact the valve seat in the closed position. The invention further comprises compressible shock absorber means interposed between the disc and the disc holder. The shock absorber functions to lessen the shock forces involved when the valve disc impacts upon the valve seat at closing.