Hydrodynamic pressurizing apparatus

Abstract

An apparatus capable of stressing test specimens to relatively high stres at an ultra fast rise time, and unstress at ultra fast decay time. System components include a hydraulic pumping unit, a gas-liquid accumulator, a pressure loading valve, an intensifier, a pressure vessel, a trigger mechanism, a pressure unloading valve, a surge tank, and system controls. To increase system operating response, the discharge port of the accumulator is connected directly to the inlet port of the loading valve. An exit port of the loading valve mounts directly to the inlet low pressure port of the intensifier. The high pressure outlet port of the intensifier mounts directly to the bottom inlet end of the pressure vessel, and the inlet port of the unloading valve mounts directly to a second exit port of the loading valve. The pressure vessel chamber and the intensifier's high pressure chamber are pre-filled as a closed system, with a low compressible fluid. Also, a high speed trigger mechanism in conjunction with the high speed loading valve is used. The trigger mechanism operates to move the trigger valve's spool at high speed for effectuating instant release of fluid pressure behind the loading valve's plunger. The resulting rapid retraction of this plunger will operate to dump pressurized fluid from the accumulator to the low pressure side of the intensifier. Rapid release of fluid pressure from within the pressure vessel is accomplished by operation of the unloading valve in conjunction with the loading valve for effectuating rapid discharge of fluid from the intensifier's low pressure end to the surge tank.