What Is Bearing Life? How to Conduct Bearing Life Testing?

The quality and performance of bearings determine their service life. The emergence of bearing testing machines marks an era of upgrading and renewal for bearings—these machines can test bearing life and enable in-depth analysis of product and raw material performance. The editorial team from Kaiyuan will specifically explain what bearing life is and how to conduct bearing life testing.

I. Definition of Bearing Life

1. Operational Damage

During the operation of rolling bearings, failures and damage often occur. These issues are generally preventable if correct preventive measures are taken in advance. However, even with various preventive measures, bearings may still be damaged due to material fatigue—which is unavoidable. This type of damage is what we refer to as "end of life."

2. Fatigue Spalling

Even if a bearing is correctly installed and properly lubricated during operation, if it is subjected to high loads, the load on the surfaces of the balls and raceways will be cyclic (even if the external load is static). Over time, the material will experience rolling fatigue, leading to "end of life." The phenomenon manifests as sudden flaking of parts of the internal contact surfaces of the bearing during rotation, resembling fish scales—this is called fatigue spalling. We define the occurrence of fatigue spalling as the end of the bearing’s life. For a batch of bearings, if 90% of them remain qualified after 1 million rotations (referred to as L10 life), this is considered the achievable service life of the bearings.

3. Comprehensive Reflection of Indicators

Bearing life is a comprehensive reflection of various indicators such as dimensional accuracy, noise level, and material quality. Numerous factors influence bearing life, including steel purity, heat treatment quality, machining precision, cleanliness, and component dimensions. Some of these factors are detectable and can be identified in advance, while others are undetectable or difficult to discover.

II. Bearing Life Testing

1. Load Application

Bearing life testing can be performed using bearing testing machines—equipment designed to conduct rotational fatigue life tests on bearings under applied loads.

2. Simulated Operation

The standard method for verifying bearing life is through bearing life testing machines. By conducting simulated life tests on bearings, manufacturers can gain insights into their comprehensive performance, promptly address identified product defects, and optimize product quality. These tests involve intensive or simulated operation of bearings under simulated environments and working conditions to evaluate dynamic performance closely related to service life, including high-speed performance, high-temperature resistance, and overall comprehensive performance.

The above is an introduction to what bearing life is and how to conduct bearing life testing. For more information, please follow Kaiyuan Intelligence. If you have further questions, feel free to contact us via phone or message!