In a circuit which uses two parallel pumps, this valve unloads the larger pump to tank once the pressure setting of BP has been reached. From this point the circuit will only be supplied by the smaller pump at a higher pressure AP, therefore consuming less energy.
V0512 V0513 V0514
Zinc-plated steel with internal parts in hardened and ground steel
Connect BP to the higher flow pump, AP to the lower flow pump, T to the tank, M to the eventual manometer and U to the hydraulic circuit.