Senior Engineer, NTN Corporation, Mie,
Project Manager, NTN Corporation,
Pages: 13 Published: Jan 2002
The failure mode assumption of Lundberg-Palmgren's bearing life theory is that cracks initiate below the rolling contact surface. Therefore, modification is required to predict surface originated flaking life under contaminated lubrication. A new life estimation method, which can also be applied to surface originated flaking, is described. This method comprises the calculation of a volume element life, which is related to the local stress below the contact area, and then calculating the total life of the contact stressed region. The theoretical result was compared with experimental endurance test results, and both results showed that the lower the bearing load, the greater the life was reduced from the basic rating life. Additional groups of bearing test lives, gathered from references, were also analyzed and the same trend was observed. From these results, an appropriate diagram for the life modification factor is obtained against P/C ( P : equivalent bearing load, C : basic dynamic capacity ) under various contaminated lubrication conditions.
rolling bearing, rolling contact fatigue, bearing life, contaminated lubrication, life calculation, local stress
Paper ID: STP10856S