Hydraulically-operated valve MRQA series

for oilunloading

MRQA is a pressure relief and safety valve with automatic unloading. Upon reaching the set value, the valve freely unloads the pump and puts it under pressure again when the pressure values descend in the circuit to correspond to 63% or 75% of the set value. In order to assure this operation, it is necessary to use an accumulator (see hydraulic diagram) that guarantees pressure maintenance in the circuit. A check valve, incorporated in the panel or available as a plate under the valve MRQA/C, prevents the accumulator unloading through the open valve. This system maintains the pressure in the hydraulic circuit, avoiding heating of the oil and reducing energy consumption. It is recommended to place the accumulator as close as possible to the MRQA, without reducing the connection size. The cycle time depends on the pump flow rate, the accumulator capacity and pre-charge, and the flow requirement of the system.