Contact stresses in conical rollers under normal and tangential loads

Abstract

Load transfer between components in engineering assemblies often causes very high localized stresses generally called contact stresses. The contact stresses are highly concentrated close to the contact region and decrease rapidly in intensity with distance from the point of contact, so that the region of practical interest lies close to the contact interface. The nature of stresses arising from the contact between two bodies is of great importance and attracted the attention of many researchers. But most of them were analyzed using simple geometries i.e. sphere on plane, sphere on sphere, and cylinder on cylinder. This work has focused on complicated geometries rather than simple geometries by considering conical rollers in contact. When two geometrical and materially identical conical rollers come into contact with each other under the application of a uniform compressive load in rolling, the contact patch appears in the form of a trapezoid, in contrast with two cylinders where the contact area is rectangle. The trapezoid shape of the contact area arises because the radius of curvature of either cone varies along the axial direction and contact length. So, radius of curvature will be a function of vertex angle as well as length of the contact, where in the case of cylindrical contact it is same through out the cross. section of the contact. The work has also considered tangential loading along with normal loading. The stress functions have been solved numerically to find stress distribution with variation of contact geometries. Stress components in different axes have been investigated with variation of contact geometries for both normal and tangential loading. Half width distribution, pressure distribution and stress distribution along the length have been also investigated for different vertex angle as well as for different materials. The validity of numerical results has been done using a commercial finite element simulating software, Ansys. The results of the numerical technique are found to be consistent with the finite element simulations in predicting pressure, its distribution and the contact stresses in conical rollers.