The use conditions of the internal combustion forklift transmission are relatively harsh, and the load changes are relatively large. Its structural design is very compact and the degree of reinforcement is high. The working temperature in the box is very high during actual operation. Therefore, the steam generated by the lubricating oil in the box fills the box space, which increases the pressure in the box, and each sealing interface bears this pressure. The impact of oil and gas often flushes out at the weakest point and leaks. Once a leak occurs, a channel is formed and the leak becomes more and more serious. If the transmission has multiple oil leaks and occurs when the case temperature is high, this is generally due to the fact that the ventilation plug on the transmission cover is blocked by dust and mud, which makes the ventilation performance worse. The heat and oil vapor generated by the gears in the box under heavy load and high-speed rotation cannot be removed in time, resulting in a higher pressure in the box than the atmospheric pressure outside the box, and the oil temperature is also greatly increased, making the lubricating oil thinner. In use, leakage of lubricating oil is one of the most common faults in the maintenance of transmission forklifts. After the lubricating oil seeps into the building, it will cause a shortage of gear lubricating oil, resulting in early wear and damage of gears and bearings and shorten the service life of the transmission. , and also pollute the environment. Therefore, it is of great significance to study the principle of the leakage of transmission oil in the forklift truck, analyze the reasons, and take effective technical measures to repair the oil leakage fault of the forklift transmission.
In addition to the above factors, the oil leakage of the forklift transmission has the following reasons:
1. The forklift oil seal or flange is worn, and the forklift gear oil exceeds the specified standard;
2. The clearance of each shaft end is too large, the forklift bearing seat hole and bearing are loose, the gasket is damaged or failed, and the sealing gasket is damaged or missing;
3. The processing quality of the surface of each seal does not meet the requirements of the product drawing, the oil seal is aging and failing, and the fastening bolts are loose;
4. Improper use of lubricating oil, such as mistakenly adding the rear axle hyperbolic gear oil into the forklift transmission (that is, mixing it with the gear oil in the forklift transmission) will cause a lot of foam in the lubricating oil in the box, causing the liquid level to rise. High (with foam). The oil leaks into the bottom cover of the clutch housing through the first bearing cover of the forklift transmission, and in severe cases, the friction plates will be stained with oil.