Patent ID: 8893745

Claim:
A pressure relief valve for use in hydraulic, oil-in-water and water assemblies, in particular for hydraulic props used at a pressure above 400 bar in underground mining and tunnel construction, comprising a closing unit ( 10 , 50 ), which is arranged displaceably between a pressure medium inlet ( 7 ) and a pressure medium outlet ( 8 ) against the force of an adjustable valve spring ( 6 ) and which at normal pressure is kept in a sealing position by means of the valve spring ( 6 ), characterized in that between the pressure medium inlet ( 7 ) and the pressure medium outlet ( 8 ) an annular channel ( 15 ) that is sealed by the closing unit ( 10 , 50 ) with respect to the pressure medium outlet ( 8 ) is configured, wherein the closing unit ( 10 , 50 ) is acted on in case of pressure peaks such that it can be moved into the open position against the force of the valve spring ( 6 ) and a valve shaft ( 18 ) and/or an inner bore ( 9 ) receiving it are configured to generate a differential pressure relieving the valve spring ( 6 ), and wherein a sealing cone ( 17 ) is detachably connected to the valve shaft ( 18 ) by means of a countersunk screw ( 25 ) that also captures a spring plate ( 24 ).