If a load sensing valve fails, how can it be diagnosed and repaired?

The load sensing valve is one of the key components in the hydraulic system. It regulates the system pressure to ensure that the hydraulic system can still operate efficiently when the load changes. When the load sensing valve fails, it may cause the system efficiency to decrease, consume too much energy, or affect the normal operation of the equipment.
The first step in fault diagnosis is to check the performance of the system. When there is a problem with the load sensing valve, the hydraulic system may experience excessive or low pressure, unstable flow, or slow movement. At this time, the operator can observe the working status of the hydraulic system and combine monitoring tools such as pressure gauges and flow meters to preliminarily determine the possible problems with the valve.
Next, it is necessary to disassemble and inspect the load sensing valve. During the disassembly process, it is necessary to cut off the power supply and hydraulic oil of the hydraulic system to ensure safety. After disassembling the valve body, check the various components in the valve, including springs, slide valves, seals, etc. Pay special attention to check for wear, corrosion, leakage or impurity blockage. If obvious damage or foreign matter is found inside the valve body, it can be judged that it is the cause of the failure.
If contamination or impurities are found inside the valve body, the valve body and related components should be thoroughly cleaned and ensure that there are no contaminants in the hydraulic system. Contamination is one of the common causes of load sensing valve failure, especially when the hydraulic oil is of poor quality or the system is not properly maintained, impurities can easily enter the valve body and cause sticking or leakage. After the cleaning work is completed, the valve can be reassembled and the sealing performance can be checked to ensure that there is no leakage.
The spring and sensor of the load sensing valve are also parts that need to be checked. If the spring loses its elasticity, the valve may not respond to load changes and affect pressure regulation; if the sensor is damaged, it may not accurately detect the load, resulting in unstable pressure control.
After all parts are cleaned and inspected, the load sensing valve can be adjusted as needed. Some load sensing valves have an adjustment function that allows their pressure setting value to be changed by adjusting the screw. If the hydraulic system can operate normally after the adjustment, it means that the repair work has been completed. If the adjustment is still ineffective, you may need to consider replacing the load sensing valve.
After the repair is completed, the system should be tested. Restart the hydraulic system and observe the working status of the load sensing valve. Check whether the pressure change of the valve under different loads is normal, whether the flow is stable, and the overall operation of the hydraulic system. After ensuring that all parameters meet the design requirements, it can be officially put into use.