Common problems encountered in hydraulic pump repair
The common problems encountered in hydraulic pump repair include abnormal pressure in the hydraulic system, inability to increase or decrease pressure. Pressure is one of the two basic parameters of the hydraulic system, which largely determines the performance of the hydraulic system. This problem manifests as: when regulating the pressure of the hydraulic system, there may be a failure to establish the system pressure, a lack of pressure, no pressure at all, perhaps the pressure cannot be adjusted down, or it may rise and then fall down again, and the regulated pressure is unstable and fluctuates greatly.
1. The impact of abnormal pressure
① Execution components (such as hydraulic cylinders, hydraulic motors) do not act or, although they act, stop operating with a load or are powerless, unable to overcome the load and do work;
③ Some valves that rely on pressure control cannot operate, such as hydraulic directional valves, hydraulic control check valves, plug-in valves, pressure relays, etc. Hydraulic maintenance also leads to the hydraulic system not functioning properly:
⑤ Malfunctions, including safety accidents, occur due to uncontrolled stress regulation,
Overheating of the motor is a common problem that occurs during the operation of high-temperature oil pumps. The specific analysis and testing are as follows:
1. Does the usage range (flow rate, head) exceed the design requirements of the high-temperature oil pump?
Select the appropriate motor according to the series spectrum
2. Does the medium density exceed the configuration of the high-temperature oil pump motor?
Configure a suitable motor for the Dajiang high-temperature oil pump
3. Is the packing gland pressed too tightly or the mechanical seal spring adjusted too tightly?
Adjust the compression amount of the spring for the pressure cover or mechanical seal again
4. The assembly quality of the gear pump is poor, and there are friction areas or the motor and pump shaft are not concentric during hydraulic maintenance
During hydraulic maintenance, identify the cause of the malfunction from the following three points and make improvements to the system:
(1) Check the internal leakage of the boom cylinder. A simple method for Z is to raise the boom and see if there is any noticeable free descent. If the drop is obvious, disassemble the oil cylinder for inspection. If the sealing ring is worn, it should be replaced.
(2) Check the control valve. Firstly, clean the safety valve and check if the valve core is worn. If worn, replace it. If there is still no change after the installation of the safety valve, the hydraulic maintenance should check the wear of the control valve core again. The clearance limit is generally 0.06mm, and if the wear is severe, it should be replaced.
(3) Measure the pressure of the hydraulic pump. If the pressure is too low, adjust it. If the pressure still cannot be adjusted, it indicates that the hydraulic pump is severely worn.
