Performance fixes for compact high torque hydraulic motors


The compact high torque motor sometimes encounters some situations during use. When these situations occur, you don't have to panic. The following are some of the reasons we have summarized.

Reasons for the weakness of the hydraulic motor

According to the analysis of the causes of the wear of the distribution plate, the main reasons for the weakness of the hydraulic motor are as follows:

Due to the wear of the valve plate, the inlet and return oil passages are connected at the valve plate, part of the high-pressure oil leaks, the oil pressure flowing through the stator and rotor pair drops, the flow decreases, and finally the output speed and torque of the motor drop.

Due to the wear of the valve plate, its relative position in the valve body changes, and the spring on the valve body reduces the pre-tightening force and the fitting force between the valve plate and the valve plate, which aggravates the leakage of hydraulic oil and causes the performance of the hydraulic motor to decline.

The increase of hydraulic oil temperature causes its comprehensive performance to decline, further reducing its ability to drive the cycloid rotor to rotate.

After inspection, there is no obvious wear on the joint surface of the stator and rotor pair and the bearing housing and valve disc matched with both sides. The movement is normal without lag and will not cause performance degradation.

Causes of valve plate wear

It can be seen from the working principle of this kind of hydraulic motor that the distribution plate and the cycloid rotor are connected by a small linkage shaft to rotate together, and at the same time the distribution plate slides and rotates on the valve plate. The reasons for the excessive wear of this friction pair are as follows:

When a new hydraulic motor is just installed, because the motor housing is not filled with hydraulic oil, the friction surface of the friction pair lacks sufficient lubrication and causes wear. Especially in the early stage of work with a large load, it will further aggravate the wear of the distribution plate.

The failure of the filter element of the hydraulic system causes particulate impurities to be mixed into the hydraulic oil, and small particles enter the friction surface during the rotation of the valve plate, causing abrasive wear on the friction surface.

The friction surface of the distribution plate and the valve plate has worse wear roughness, which increases the impurity storage space between the friction pairs, and the particles entering the friction surface and the ground metal particles rotate together with the distribution plate, which aggravates the wear.

Due to the wear between the valve plate and the valve plate, the hydraulic oil is connected by a gap between the inlet and return oil passages. Under the action of high pressure, the sealing, cleaning and heat dissipation performance of the hydraulic oil is reduced, and the oil temperature is increased. wear.

Reasons for oil leakage of output shaft oil seal

After dismantling and testing, the axial and radial clearances of the output shaft meet the standard, and there is no obvious wear on the mating surface of the output shaft and the oil seal. However, it was found that the oil seal rubber aged and hardened, and its elasticity became poor. After the oil seal lip is worn, the preload force and oil sealing performance decrease, and the oil temperature is too high to accelerate the wear of the oil seal lip; in addition, due to the internal leakage of the hydraulic motor, the back pressure in the casing is too high, which makes the oil seal lip wear and tear and the oil spill further intensified.


There is a lot of hydraulic motor knowledge on the official website of HANJIU TECHNOLOGY. It is an excellent supplier of hydraulic motors. If you want to know more hydraulic motor types, please Log in to 

hydraulic motors suppliers

hydraulic motors for sale

hydraulic motors price

hydraulic motors pdf

hydraulic motor vs electric motor

hydraulic motor price


Read more!