Lubrication characteristics of commercial vehicle hub bearings
The car hub has experienced the first generation of ordinary double row bearings, the second generation of single flange double row bearings, and the third generation of double flange double row bearings. Up to now, the double flange double row bearings and universal joint are integrated, characterized by high temperature, high speed, and fretting wear; The drum of commercial vehicles ranges from two independent tapered roller bearings to an integrated set of two tapered roller bearings, characterized by extreme pressure and long service life.
Wheel hub bearings, as one of the most important components in automobiles, are closely related to their lubrication technology and the continuous improvement of the bearings themselves. The hub bearing grease itself should be able to form a solid oil film, providing wear-resistant and reliable lubrication for the friction parts. The grease used should have five main properties: high temperature resistance, structural stability, wear resistance, water resistance, and long service life:
One is its excellent high-temperature resistance, ensuring that the maximum operating temperature of the vehicle meets the requirements of 130~150℃ under harsh conditions such as heavy loads and continuous braking on downhill slopes in mountainous areas. The lubricating grease droplet point is mostly around 290°C.
The second is good mechanical stability and adhesion performance. Ensure that lubricating grease is not prone to excessive softening and loss under long-term mechanical shear caused by bearing operation, which is beneficial for preserving the lubricating oil film on the bearing surface and avoiding early failure of bearing lubrication or causing safety issues; The change in cone penetration of lubricating grease after 100000 operations should not exceed 15%.
The third is sufficient wear resistance and load-bearing capacity. Ensure that the hub bearings do not cause abnormal wear even under impact loads; If PB is above 980N.
Fourthly, it has good water and rust resistance. It is suitable for harsh driving environments and can even prevent corrosion of chassis components and protect metal components under water pollution conditions.
Fifth, it has a longer service life and excellent lubrication performance. To avoid metal fatigue and spalling caused by simultaneous axial and radial loads on the wheel hub bearings, and to extend the maintenance cycle, a maintenance mileage of 50000 to 100000 kilometers is required.
In addition, good low-temperature starting performance, antioxidant stability, and compatibility with rubber are also required. Overall, extending the service life of commercial wheel hub bearing grease depends on the joint improvement of bearing and grease quality.
Selection and application of lubricating grease for commercial wheel hub bearings
According to the specific working conditions of commercial vehicle hub bearings, the lubrication conditions of automotive hub bearings are relatively harsh due to the influence of vehicle type, speed, road conditions, and climate environment. It is required that the hub bearing grease has excellent mechanical stability, water and rust resistance, oxidation stability, adhesion, and extreme pressure and wear resistance. The base oil of the hub grease is mainly mineral oil, supplemented by semi mineral oil, and EP and solid anti wear agents are added.
Ordinary commercial vehicles generally use general automotive lithium-based grease series products such as MP multi-purpose lithium-based grease. With the improvement of overall automotive technology and road conditions, modern cars are developing towards high efficiency, heavy load, energy conservation, and environmental protection. They have put forward stricter requirements for the long life and temperature resistance of automotive grease, especially for wheel bearing grease under high-speed and heavy load conditions. Ordinary lithium based grease is increasingly exposed to its defects, such as poor temperature resistance and impact load resistance High temperature loss and poor adhesion have become its fatal weaknesses.
Extreme pressure composite lithium based products such as Kunlun HP-R high-temperature lubricating grease and Kunlun heavy-duty vehicle hub lubricating grease should be used for large passenger cars with a load capacity of 5 tons or more, which can meet the performance requirements of high-speed and heavy-duty vehicles for lubricating grease. For example, after applying Kunlun HP-R high-temperature grease to the wheel hub bearings of a 35 ton commercial vehicle for 68635 kilometers, there is still lubricating grease attached to the wheel hub bearings, maintaining the lubrication effect.
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VAFEM specializes in the supply and support of automotive bearings across virtually every vehicle type and application area. Because of our unprecedented ability to deal with virtually all the worlds major quality bearing manufacturers we can competitively supply a vast range of automotive bearings. Below you will find details of typical products we can supply based on vehicle manufacturer brand. If your in a hurry or have an OEM requirement then please contact us at any time. We respond to ALL enquiries, whether you require 1 bearing or 100,000!
2023-04-18