Introduction of 718C/ACP4 Standard Series

The fatigue life of ultra-precision angular contact ball bearings generally depends on the working life of the lubricant. In many cases, the life of the lubricant determines the life of the bearing. The relative influence on the fatigue life of the bearing is relatively small.

Fatigue load: In order to test the fatigue load, the load ratio So is calculated according to the following formula:

So=Co/Po

So: Fatigue load ratio (dynamic load safety factor)

Co: Basic static load rating N

Po: The equivalent static load can be calculated using the equivalent static load formula, but the dynamic load is used in the calculation. The equivalent static load Po is calculated based on the axial and radial loads of the bearing. The stress caused by this force at the center point of the force area between the rolling element and the contact surface of the raceway is equal to the stress caused by the actual load composition. For the bearing that actually bears the load, its load-bearing capacity should be checked.

If the dynamic load ratio So>8 is the main prerequisite for satisfying the fatigue load, a more accurate method is to measure the contact stress of the bearing separately, or use a dedicated calculation software to detect the dynamic performance of the bearing. If the effective lubricating oil film (viscosity ratio k≥2) and extremely high cleanliness and other conditions can meet the requirements, there is no need to calculate the rated life of the bearing. If these prerequisites are not met, the influence of lubrication and cleanliness on the bearing can be calculated manually through the revised life calculation formula ISO281 or through the computer-aided calculation of DIN281 Appendix 4.

Introduction of 718C/ACP4 Standard Series

The fatigue life of ultra-precision angular contact ball bearings generally depends on the working life of the lubricant. In many cases, the life of the lubricant determines the life of the bearing. The relative influence on the fatigue life of the bearing is relatively small.

Fatigue load: In order to test the fatigue load, the load ratio So is calculated according to the following formula:

So=Co/Po

So: Fatigue load ratio (dynamic load safety factor)

Co: Basic static load rating N

Po: The equivalent static load can be calculated using the equivalent static load formula, but the dynamic load is used in the calculation. The equivalent static load Po is calculated based on the axial and radial loads of the bearing. The stress caused by this force at the center point of the force area between the rolling element and the contact surface of the raceway is equal to the stress caused by the actual load composition. For the bearing that actually bears the load, its load-bearing capacity should be checked.

If the dynamic load ratio So>8 is the main prerequisite for satisfying the fatigue load, a more accurate method is to measure the contact stress of the bearing separately, or use a dedicated calculation software to detect the dynamic performance of the bearing. If the effective lubricating oil film (viscosity ratio k≥2) and extremely high cleanliness and other conditions can meet the requirements, there is no need to calculate the rated life of the bearing. If these prerequisites are not met, the influence of lubrication and cleanliness on the bearing can be calculated manually through the revised life calculation formula ISO281 or through the computer-aided calculation of DIN281 Appendix 4.