Investigation of slippage and wear in rolling bearings of machines

The purpose of this work was to study the processes of slipping and wear in the sliding bearings of machines. It is determined that slippage in bearings is the main cause of bearing parts failure according to the criterion of wear. Analytical relations for determining the amount of slip and sliding path in the bearing are presented. For experimental research of sliding in rolling bearings the test installation is designed. Experimental tests on the effect on load slip, sliding speed and lubrication conditions in the bearing were performed. The model of wear of rings of the sliding bearing on the basis of a solution of a wear contact problem is offered. The formulas for calculating wear and parameters of the wear model are obtained. The obtained results are recommended to evaluate the influence of design and technological factors on the durability of rolling bearings by the criterion of wear.

A Simple Model for the Wear Accumulation in Partial Slip Hertzian Contact

A two-dimensional wear contact problem with a stick zone is considered for a Hertzian cylindrical contact configuration and Archard’s equation of wear. A one-free-parameter simple model for the wear volume accumulation during the reciprocating wear process, which occurs in two symmetric variable slip zones, is developed and validated against numerical solutions available in the literature. The developed model takes into account the observed effect of non-monotonic evolution of the friction dissipated energy. The presented analytical modeling framework does not make use of any fitting parameters to be evaluated from experiments. The only free dimensionless parameter is suggested to be fixed based on numerical simulations for the maximum of the frictional damage that is proportional to the cumulative wear rate.

Inverse wear contact problem of the friction unit

In this study, theoretical analysis for defining the function of displacements of a hub’s external contour points and microgeometry of the friction unit providing the absence of initial wear that holds to the end of running-in period, was carried out based on a rough friction surface model. A closed system of algebraic equations admitting to obtain the solution of the problem of optimal design of a friction unit depending on the geometrical and mechanical characteristics of a hub and plunger was constructed. The found function of displacements of the hub’s external contour points and microgeometry of friction surface provide wear resistance increase of friction pair. Calculations for friction units applied to the borehole sucker–rod oil pumps were considered as an example.