1.The impact of materials;
In terms of bearing material technology, the improvement of bearing life is mainly ensured through material selection, material assurance, and heat treatment. Rolling bearings are generally made of high carbon chromium bearing steel, and their chemical composition remains almost unchanged. However, the purity of materials varies with different smelting methods, which has a significant impact on their lifespan. Under the same contact stress conditions, the contact fatigue life of Zhen Ⅳ 4 ceramic bearings is better than that of steel bearings; Ceramic ball bearings are preferred for high-speed, light load, and low impact loads. It can be seen that the influence of materials on the fatigue life of bearings is very significant.
2.The influence of surface roughness;
Fatigue cracks usually originate from the surface, so the surface has a significant impact on the lifespan of the component. The smoother the surface, the longer the initiation time of fatigue cracks. The surface treatment technology of rolling elements and rings in rolling bearings can change the hardness of the rolling surface layer, residual stress distribution, and overall strength of the material, thereby improving the bearing life.
3.The influence of temperature;
The influence of temperature: Both fatigue models based on subsurface stress and models starting from surface defects have not taken into account the impact of heating in the bearing contact area on fatigue life. In fact, after continuous operation, bearings will inevitably experience a certain temperature rise, and the magnitude of this temperature rise should be related to the thickness of the lubricating oil film between the contact pairs, the surface characteristics of the contact parts, as well as parameters such as load and operating speed. At the same time, after the temperature rises, there will inevitably be a temperature distribution in the bearing ring and rolling element, and thermal deformation will occur due to the influence of thermal expansion, which will affect the operating accuracy of the bearing. So the influence of temperature rise and heat on fatigue life cannot be ignored.
4.The impact of lubrication technology;
In terms of bearing lubrication technology, the lifespan of bearings is mainly improved through the selection of lubricants and lubrication methods. Lubrication technology has become one of the most critical factors in improving the lifespan of bearings. Especially for sealed bearings, grease life has become another synonym for bearing service life, that is, grease life is the bearing service life.
5.The impact of operational speed;
The influence of operating speed: The fatigue life of bearings is related to instantaneous contact time. Instantaneous contact time refers to the time required for the rolling element to roll over the ring and the elliptical width of the ring raceway under maximum load. As the speed increases, the instantaneous contact time increases, and the fatigue life of the bearing decreases. The slower the operating speed of a bearing, the longer its lifespan in terms of revolutions per minute. On the other hand, the duration of instantaneous contact time can also affect surface residual stress, indirectly affecting fatigue life.
6.The impact of load;
The influence of rolling element parameters and curvature coefficient on the fatigue life of deep groove ball bearings has been studied, and it has been shown that the size of the load has a significant impact on the fatigue of the bearing. The fatigue life of rolling bearings largely depends on the maximum rolling element load. Therefore, an increase in load leads to a significant increase in the maximum rolling element load and a decrease in fatigue life.