Torque Unloading Relief Valve

These valves are used to operate the pumps with minimum load in accumulator circuits or in high-low pump circuits. In accumulator circuits, when the system pressure reaches to a cut out pressure (adjusted maximum), the valve acts to divert the pump delivery to the reservoir at low pressure, thus the pump is unloaded automatically.

To adjust the pressure, loosen the lock nut and turn the pressure adjustment handle slowly clockwise for higher pressures or anti-clockwise for lower pressures. After adjustments, do not forget to tighten the lock nut. Take care not to neglect connecting the drain pipe to the reservoir; otherwise not only will the valve fail to operate properly but also the line pressure will rise infinitely. Extend the end of the drain pipe into fluid. Limit the pressure drop between the valve and the accumulator in an accumulator circuit below 10% of the cut-out pressure. Limit the drain port back pressure below 2% of the cut-out pressure.