Bearing Grease Use Knowledge--Huzhou Xinshi Lubricants

1. Empty hub lubrication

There are two methods for lubricating the front and rear wheels of a car: one is to fill the inner cavity of the hub with grease, in addition to the bearing. This traditional method is called full hub lubrication; the other is only The bearing is loaded with grease, and the hub cavity is only thinly coated with a layer of grease to prevent rust, which is called hollow hub lubrication.

When lubricating a wheel hub bearing, some people are used to filling the hub cavity with grease, which is not only useless but also harmful. After the hub cavity is filled with grease, the bearing is poorly cooled, the resistance is increased, the temperature is increased, and the grease is deteriorated; the grease expands by heat and the oil seal is squeezed. The grease that flows out rubs against the brake shoe. Failure of the brakes leads to accidents. In the cavity, only a thin layer of grease is used to prevent rust, which not only can prevent the above-mentioned hazards, but also can save a lot of grease.

In order to liberate CAl091, for example, a full-hub lubrication system is used to maintain a grease capacity of 3.5-4kg for 4 wheels in a maintenance period (17500km), while the use of a hollow hub requires only about 0.5kg of grease, which saves more than 80% of lubrication compared to full-hub lubrication. According to tests, with the same force to rotate the wheel, the hollow hub can be rotated by 11.5 revolutions, and the full hub lubrication by only 6 revolutions. This proves that the hub lubrication is also beneficial for saving power. Therefore, in actual work, empty hub lubrication should be used.

2. Reasonably choose the type and grade of grease

At present, most vehicles in China use No. 2 and No. 3 calcium-based greases, which can meet the requirements under normal conditions of use. The No. 2 calcium-based grease has a small consistency, considering the ease of filling and reducing frictional resistance. If the use of temperature is not high, with 2 calcium grease is more appropriate. However, the calcium-based grease No. 2 has a lower gao use temperature than that of No. 3 calcium base grease, such as in the southern summer or mountainous areas. Under high bearing temperatures, it is not as good as No. 3 calcium base grease.

The problem with calcium-based greases in use is that the temperature resistance is poor, and its use temperature cannot exceed 70-80°C. Otherwise, it will soften the loss. The car travels under different conditions and the temperature varies greatly. For example, on a general mountain road in the Beijing area, use a general driving method. The hub bearing temperature is about 60°C. You can use the No. 2 or No. 3 calcium base grease. If more downhill, frequent use of brakes, brake hub generates a lot of heat, these heat will be transmitted to the bearing, bearing temperature up to 70-80 °C, if the use of calcium-based grease, it will produce oil phenomenon. In this case, calcium sodium grease (or ball bearing grease) or lithium grease should be used. Calcium-sodium-based greases have poor water resistance and cannot be used in cars that often wading. In the summer in the south, especially in the long slope, the bearing temperature can exceed 100°C, and lithium-based grease is used. Otherwise, the grease will be softened and lost. Not only will the grease be wasted, but also the bearing will be damaged in advance.

3. Lubricate the leaf spring with graphite grease

Some drivers often do not use graphite grease during the three-level maintenance. Instead, they use calcium-based grease to lubricate the leaf springs. Some even brush only the engine oil. This leaves the leaf springs to be easily damaged, especially under conditions of poor construction sites, mountains, and road conditions. When the vehicle is traveling, the vehicle bumps and the leaf spring has a large impact load and is more likely to be damaged. Graphite grease contains graphite and graphite to fill the rough surface between steel plates, which improves the ability to withstand pressure and impact loads. Simulated automotive leaf spring vibration tests showed that leaf springs using calcium-based grease continuously vibrated 700 times for breakage, whereas leaf springs using graphite grease only continuously vibrated 1500 times before breaking, and their service life was more than double.

4. Containers and tools should be cleaned

When packing and distributing grease, check that the containers and tools are clean. Grease containers should be tightly sealed to prevent the mixing of mechanical impurities. When used, if any grease, debris, etc. are found on the surface of the grease, they should be scraped off and must not be mixed. Special tools should be used to distribute grease, and plastic containers should be used after containers and tools are used. After digging the grease, the remaining grease surface should be leveled to prevent oil separation.