Hydraulic balance valve Excavator hydraulic cylinder valve core NFED-LHN

When the general relief valve is working, it is completely adjusted and controlled by the spring pressure. It can adjust the pressure of hydraulic oil by pressure. In general, if the pressure of the hydraulic oil is smaller than the pressure required for the work, the spool is pressed by the spring at this time and is in the hydraulic oil flow inlet attachment. But once the pressure of the hydraulic oil is greater than the allowable pressure in the work, in other words, when the pressure is greater than the spring, the spool is naturally pushed up by the hydraulic oil, and the hydraulic oil will flow into and flow to the tank.

When the pressure of the hydraulic oil gradually increases, the spool will also be gradually capped. . At this time, the hydraulic oil flows through the relief valve to the relevant tank flow will gradually increase, when the pressure of the hydraulic oil is reduced to equal or less than the spring pressure, the spool will naturally fall to seal the corresponding inlet of the hydraulic oil.
The hydraulic oil output by the general oil pump has a fixed value of pressure, and the corresponding pressure of the hydraulic oil used by the corresponding working cylinder is generally much smaller than the pressure output by the oil pump. At this time, we will see that when the operation is normal, there will be hydraulic oil flowing into the tank through the relief valve device. This can ensure that the hydraulic cylinder has a normal working pressure.