Pressure relief valve for protecting hydraulic brace systems in downhole machinery from pressure surges has damping chamber between valve piston and equalising chamber and sheet spring biased by valve spring at top of damping chamber

摘要

The pressure relief valve for protecting hydraulic brace systems in downhole machinery from pressure surges has a damping chamber (20) between the valve piston (6) and a pressure equalising chamber (14) in front of an outlet bore (13). A sheet spring (29) biased by a valve spring (32) is positioned at the top of the damping chamber.