Power Unit Operation Process

When the hydraulic power unit starts to work, the gear pump draws the hydraulic oil from the oil tank and moves it into the accumulator. This process continues until the pressure in the accumulator reaches a predetermined level. At this time, the charging valve switches the pumping action and begins to circulate the fluid. This allows the pump to release the oil back to the tank through the charging valve at minimum pressure. A special check valve prevents liquid from flowing out of the accumulator, but if the pressure drops significantly, the charging valve will restart and the accumulator will be refilled with liquid. Next, the pressure reducing valve regulates the oil flow to the actuator.
If the accumulator is equipped with a fast stroke device, it can be connected to other accumulators so that they can also charge pressure. Usually, an automatic thermostat or fan will mitigate the temperature rise. If the liquid in the system starts to overheat, the temperature switch can turn off the motor pump. If the liquid level is too low, it can also help refill the tank. If the hydraulic power unit has more than one electric pump, the flow switch can make them use alternately to prevent the fluid supply from decreasing. The pressure switch can be used to adjust the pressure of the accumulator. When the pressure drops too low, the monitoring system can alert the operator, thus increasing the risk of power unit failure.