Hydraulic pump motor: detailed use and maintenance

Update:03 Dec 2021
Summary:The hydraulic oil pump and the hydraulic pump motor will inevitably fail during use. These faults can be divided into su...
The hydraulic oil pump and the hydraulic pump motor will inevitably fail during use. These faults can be divided into sudden faults and abrasive faults. Among them, the abrasive failure mainly occurs in the later stage of the system work, which is mainly caused by the natural wear and tear of the parts. The damage to the system is mainly manifested in the failure of the sealing material, the gradual slowing down of the movement of the actuator, etc., and the impact is not significant. Sudden failures usually occur in the early and middle stages of system operation. They are mainly caused by the management personnel not following the operating requirements and procedures during use and maintenance.
Most of the damage to the system is manifested in the hydraulic pump motor. Vicious accidents such as burning damage, oil motor crawling, hydraulic component damage, and hydraulic pipeline rupture have a great impact. The frequency of these failures is closely related to routine maintenance and maintenance. In order to maintain good working conditions and long service life for a long time, in addition to establishing and perfecting the necessary daily maintenance system to reduce future wear and tear, it should also minimize the initial and mid-term emergencies. Terminology accident.
The hydraulic oil problem of the hydraulic pump motor has always been the culprit leading to the failure of the hydraulic system. Due to space limitations, I will not repeat them here, but only illustrate some typical problems.
1.1 The oil viscosity should meet the requirements
For example, it is recommended that the ZB type oil pump use hydraulic oil with a small viscosity change with oil temperature, and its viscosity range is 20-100 cst. When the ambient temperature is higher than 15℃, it is recommended to use thicker 40-2, 30 machine oil and 30 machine tool hydraulic oil. For engine oil, when the ambient temperature is lower than 25℃, YH-10 aviation hydraulic oil is recommended; domestic α-type and CB-4 type gear pumps are recommended, and No. 20 mechanical oil is recommended for YB-type vane pumps.
1.2 Keep the oil clean and maintain a certain degree of oil filtration accuracy
1) The end face clearance of the axial piston pump can be automatically compensated, the clearance is small, the oil film is thin, and the oil filtering accuracy of the oil is the highest.
2) The oil filtering accuracy of the swash plate axial piston pump is 10-15μm.
3) Solid impurities will cause wear, reduce capacity and efficiency, and cause clogging and blockage of through holes, variable mechanisms, and parts.
4) Once the oil of the hydraulic pump motor is contaminated, it should be replaced and flushed with clean oil.