In the daily operation of electric forklifts, the inability to lift is a more common failure. Many operators often have no way to start when encountering such problems. In fact, many times the culprit is the blockage of the hydraulic filter element. As the core power source of the lifting function of electric forklifts, the hydraulic filter element plays a key role in filtering impurities in the oil and ensuring the cleanliness of the oil. Once the filter element is blocked, it will directly affect the normal operation of the hydraulic system.
The principle of hydraulic filter element blockage causing lift weakness is not complicated. The lifting action of an electric forklift relies on the hydraulic pump to transport high-pressure oil to push the cylinder, and the hydraulic filter element is responsible for intercepting metal debris, dust, colloids and other impurities in the oil. When the filter element is used for too long, or there are many impurities in the working environment, the filter hole of the filter element will gradually be blocked, resulting in increased oil flow resistance, and the hydraulic pump cannot provide enough pressure for the cylinder. Eventually, the lifting will be slow or even impossible. In addition, long-term blockage may also exacerbate the wear of hydraulic pumps, cylinders and other components, causing more serious failures.
Before replacing the hydraulic filter element, it is necessary to make adequate preparations. First, park the electric forklift in a flat and well-ventilated area, pull up the handbrake and turn off the power supply to ensure safe operation. Second, prepare the new hydraulic filter element, wrench, oil receiving container, cleaning rag and other tools and accessories. Note that the model of the new filter element should match the hydraulic system of the forklift to avoid poor sealing or poor filtration effect due to model discrepancies. Finally, consult the operation manual of the forklift in advance to understand the specific installation location of the hydraulic filter element.
The specific replacement process can be divided into the following steps: The first step is to drain the old hydraulic oil. Find the oil drain port of the hydraulic oil tank, place the oil receiving container below, slowly open the oil drain valve, and close the valve after the old oil is completely discharged. Pay attention to properly dispose of the collected old oil to avoid polluting the environment. The second step is to disassemble the old filter element. Use a wrench to carefully unscrew the old filter element. During the process, avoid impurities in the filter element from falling into the hydraulic oil circuit. After disassembling, you can observe the degree of pollution on the surface of the filter element to further confirm the cause of the failure. The third step is to clean the mounting seat. Wipe the contact surface of the filter element mounting seat with a cleaning rag to check whether the sealing gasket is damaged or aging. If there is a problem, replace the new seal in time to prevent subsequent oil leakage. The fourth step is to install the new filter element. Apply a small amount of clean hydraulic oil to the sealing ring of the new filter element, then screw the filter element into the mounting seat by hand. After the sealing ring is fitted, gently tighten it with a wrench. Be careful not to use excessive force to avoid damage to the filter element or mounting seat. The fifth step is to add new hydraulic oil. According to the oil level standard specified in the forklift manual, add the appropriate hydraulic oil to the hydraulic oil tank. During the addition process, avoid the oil mixing with impurities. The sixth step is to test the lifting function. Start the forklift, repeatedly operate the lifting handle, observe whether the lifting action returns to normal, and check whether there is oil leakage in the hydraulic system to ensure that the replaced system operates stably.
In addition to replacement after failure, daily maintenance is also crucial. It is recommended to replace the hydraulic filter element regularly according to the maintenance cycle of the forklift. Generally, it can be replaced every 500 hours or so. After daily operations, the dust and debris on the surface of the forklift should be cleaned in time to reduce the probability of impurities entering the hydraulic system. Regularly check the color and condition of the hydraulic oil. If the oil is found to be turbid or black, it needs to be replaced in time to reduce the risk of filter element blockage from the source.
