P50/51 Unloader Circuit Options

The first option is the Air Actuated Unloader for Pumps

You can use this in a manual or automated circuits to load or unload a section of the pump. In whichever case it will cause the air to shift the valve to be taken from a receiver tank in the braking system. There is a spring return that the unloader valve that put it back to factory set default. These actuators are built in parts only for the P50/51 pumps.

Pressure Sensitive Unloader Pumps

When using the unloader spool that is held in the maximum flow position by a spring. When using a predetermined preference a relief valve will allow the hydraulic pressure to move the spool to tow flow position. It is a common used circuit. However if your unit needs a cylinder to fill up fast and start at a  higher pressure that is close to the end of a stroke that uses this circuit.

If you need further explanation of this, call us at 800-361-0068

sales@hydrostatic-transmission.com