Flat grinding of big bearing races end with the demanded quality of a surface

Abstract

Upon heat treatment, bearing races acquire a flatness deviation and a curvature at the end
face surfaces under the effect of residual temperature stresses. The curvature of the end faces
considerably complicates the grinding process, because the race is additionally deformed
under the effect of the magnetic field on the machine table.
The flat grinding with the periphery of a straight wheel of standards from steel of SHkh15
is probed.
Mathematical models resulted to the width of standard of constituents of cutting force,
g-ratio and roughness of the treated surface (parameter of Ra) got the method of complete
factor experiment of type 24, where 4 is a number of factors.
Algorithms and mathematical models are presented for determination of axial deformation
at grinding of big bearings races with initial deviations from flatness of end faces.
The shape of the end surfaces of the nonrigid races was analyzed with the example of the
outer races of a conical single-row roller bearing from ShKh15 steel.

The theory of small curvature bars is used for determination of maximal axial elastic deformations at the bending of race. Maximal axial elastic deformation of race at the bending of race is determined the method of More. The statistical uncertainty is expanded with the method of forces. The terms of providing of the required flatness tolerance of end surface are determined for bearing race, taking into account axial deformation of the race under the magnetic field effect on the machine table and the radial component of the grinding force.
Algorithm and method is presented for determination of optimum terms grinding of end
surface of bearing races, providing the receipt of the set requirements to quality of the treated surface (Ra, admittance of flatness, absence of grinder burns) at the maximum cutting efficiency of process.