Flushing valve In a closed circuit, the same hydraulic fl uid continuously fl ows between the pump and the motor. This could therefore lead to overheating of the hydraulic fl uid. The function of the fl ushing valve option is to replace hydraulic fl uid in the closed circuit with that from the reservoir. When the hydraulic motor is operated under load, either in the clockwise or counter-clockwise direction, the fl ushing valve opens and takes a fi xed fl ow of fl uid through an orifi ce from the low pressure side of the circuit. This fl ow is then fed to the motor housing and back to the reservoir normally via a cooler. In order to charge the low pressure side of the circuit, cool fl uid is drawn from the reservoir by the boost pump and is fed to the pump inlet through the check valve. Thus the fl ushing valve ensures a continuous renewal and cooling of the hydraulic fl uid. The fl ushing feature incorporates a relief valve which is used to maintain a minimum boost pressure and operates at a standard setting of 14 bar (other options available on request). Diff erent orifi ce sizes may be used to select varying fl ows of fl ushing fl uid. The following table gives fl ushing rate values based on a boost / charge pressure of 25 bar
