Noise of relief valve of electric high pressure oil pump and several reasons for low speed of hydraulic pump

The relief valve of liquid pump is easy to produce high-frequency noise, which is mainly due to the unstable performance of the pilot valve, that is, the air vibration caused by the high-frequency oscillation of the pressure in the front chamber of the pilot valve. The oil in the front chamber of the pilot valve is mixed with air to form cavitation and generate high-frequency noise. At this time, the air should be discharged in time to prevent the outside air from entering again. In the process of use, the second needle valve is often opened, resulting in excessive wear, so that the cone of the needle valve and the valve seat can not be closely combined, leading to the pilot flow instability, pressure fluctuations, resulting in noise. Therefore, it should be repaired or replaced in time. There is also a kind of pilot valve, due to the fatigue deformation of the spring, the pressure regulation function is not stable, so that the pressure fluctuates greatly and produces noise. At this time, the hydraulic high-pressure oil pump should replace the spring.

The speed of high pressure plunger pump will be too low in use. There are several reasons for the low speed of hydraulic pump

Due to the damage of the motor of the high-pressure oil pump with the original liquid plunger, it ran with another motor at random, resulting in small flow, small head and even unable to pump water.

If the fastening nut between the impeller and the hydraulic pump shaft is loose or the pump shaft is deformed and bent, the impeller will deviate, directly collide with the pump body, or the bearing will be damaged, which will reduce the speed of the hydraulic pump.

Wear of transmission belt: the hydraulic pump has been used for a long time, and the transmission belt is worn loose, which leads to slipping and the speed of the hydraulic pump drops.

Power machine repair failure: motor loss of excitation due to winding burning; changes in winding turns, wire diameter, connection mode; or repair of faulty parts will also cause changes in the speed of the hydraulic pump.

Improper installation: the foundation distance between the two wheels is too small or the two shafts are not parallel, so the fastening device of the driving belt is on it. The results show that the envelop angle is too small, the calculation error of the diameter of the two pulleys, and the eccentricity between the two shafts of the coupling driven hydraulic pump is too large. This will result in a change in the speed of the hydraulic pump.