Duplex Bearings—Basic Concepts of Bearing Life

According to the latest fatigue life theory of rolling bearings, a bearing of excellent design, excellent material, well-made and correctly installed. The material of this bearing will never fatigue damage as long as it is loaded lightly enough (not greater than a certain permanent limit load value corresponding to the bearing). Therefore, as long as the working environment temperature of the bearing is suitable and the change is not large, there is absolutely no solid dust, harmful gas and moisture intrusion into the bearing, the lubrication of the bearing is sufficient and just right, the lubricant is absolutely pure without impurities, and will not deteriorate;

Then the bearing will run indefinitely. The significance of this theory is not only that it provides a more reliable tool for predicting the life of mode bearings than the ISO life Ball Bearing equation, but also that it shows that the fatigue life of all rolling bearings has considerable development potential, and shows that the development of this potential Therefore, it has a profound impact on the development, quality management and application technology of bearing products. However, the infinity of bearings is only possible under laboratory conditions; and such conditions are difficult to achieve and too expensive for bearings used in the field under certain working conditions.

When bearings are used in the field, their working load is often greater than their corresponding fatigue endurance limit load. After a certain period of work, sooner or later, the material itself will reach the electrical fatigue limit, resulting in fatigue spalling and can not continue to be used. Even if the working load of some bearings is lower than their corresponding permanent limit load, wear failure will occur due to the problem of bearing contamination that is difficult to eradicate. In short, the bearings used in the field are more or less always unable to fully meet the conditions that the above-mentioned laboratories have, and a slight deficiency in any one of the conditions will shorten the service life of the bearing, which will cause the bearing life problem.

Generally speaking, the life of a rolling bearing refers to the long service period in which the rolling bearing can continuously maintain the working performance and working accuracy that meet the active requirements under the actual service conditions (including working conditions, environmental conditions and maintenance and maintenance conditions, etc.).