1.Dynamic load

Dynamic loads are the main factor affecting the service life of bearings. When selecting the type of support roller bearings, the design is based on the rolling force during the rolling process. During the rolling process, the unbalanced, vibrating, and impact loads are three times the normal load. When steel is stuck, cold-rolled steel is rolled, or foreign objects enter the rolling rolls, it can cause shock forces of ten times to several tens of times. Therefore, during the operation of the rolling mill, proper operation must be carried out to prevent the occurrence of phenomena such as steel sticking, and to avoid premature fatigue damage to the bearings.

2. Bearing materials

The chemical composition, smelting method and heat treatment method of the bearing material have a crucial impact on the service life of the bearing. Due to the influence of the working conditions of the rolling mill bearings, there are special requirements for the manufacturing of bearings. We work together with the manufacturer to have specific requirements for the material and hardness of the bearings. While ensuring the stiffness of the bearing, the hardness must not be less than HRC 58-62.

3.Working temperature

The operating temperature of bearings is generally required to be below 120 degrees Celsius. If the operating temperature exceeds 120 degrees Celsius, the temperatures of the rollers and raceways will be even higher (approximately 150 degrees Celsius), which will exceed the tempering temperature of common bearings. As a result, the hardness and dimensional accuracy of the bearings will significantly decrease, and the lubricating grease will fail.

4.Installation, sealing

The installation of bearings has a significant impact on their lifespan. The installation of bearings requires good concentricity, a sealing device that can effectively prevent the intrusion of dust, particles and moisture, and the radial clearance during operation should be adjusted appropriately. If the clearance is too small, the friction temperature of the bearing will rise, causing burn damage to the roller path surface. If the clearance is too large, the bearing will experience severe vibration, inertia and impact, resulting in high noise and reduced lifespan.

5.Lubrication

The selection of lubricating grease should be appropriate, and the amount of grease should be proper. Poor lubrication will cause early damage to the bearings. Reasonable lubrication can reduce frictional heat, prevent excessive temperature rise, reduce wear, prevent rusting, and increase sealing. For rolling mill bearings that operate continuously for 24 hours, if there is no oil supply, the working environment is poor, damp, dusty, and with high impact loads, the use of lithium-based grease can effectively solve the above problems. The correct use of supporting roller bearings is of great significance for increasing production and reducing costs. Making efforts to install, lubricate, and maintain the bearings well, so that the service life of the bearings can be controlled, and regular replacement can be carried out to avoid early damage to the bearings and prevent the occurrence of sudden accidents. However, fatigue spalling and wear of the bearings during operation are inevitable.