Unloading valve, High-Low, VEP

A stop valve or Hi-low valve is used, for example, in presses or log splitters that use two parallel pumps, one of which is a high-flow, low-pressure pump, and a second low-flow, high-pressure pump. Both pumps deliver their combined flows to the consumer until the set pressure value is reached. From then on, the large pump will be relieved to the tank and the small pump will deliver its flow at high pressure.