Micro- and macro-modifications of pivoted slider bearings: Performance comparison and texturing versus width reduction

Effects of texture, in the form of dimples covering the whole surface of pivoted sliders, are compared with those generated by macro-modification of the bearing width. The analysis is made using the Reynolds equation – in a modified form for textured surfaces – for standard operational parameters. The comparison is made for rather standard operating conditions. These conditions include those of constant load and pivot location for all calculations for a given width-to-length ratio.In the present work it is shown that modest widening of the bearing results in a thicker film and little change in the coefficient of friction, whereas damping and stiffness are lowered. Modest width reduction leads to higher stiffness and damping while the coefficient of friction may be lowered, depending on the macro-geometry.Both width shrinking and texturing reduce the minimum film thickness. For similar minimum film thickness, the width modification is found to have appreciably stronger effects than the dimples studied. For reasonably wide bearings, a width reduction produces an increase in the dynamic coefficients and a lowering in the coefficient of friction at the same timeIt is concluded that for normal standard bearings, texturing appears to be a rather inefficient means of obtaining improved performance, particularly since similar or better performance is easily obtainable much more simply by macro-design.

Research highlights
► Minor width modifications have been shown to have important effects on the performance of pivoted pads.
► The effects caused by width modification are compared to those generated by texturing the whole pad surface.
► This comparison of effects caused by macro- and micro-modification shows that the former are stronger than the latter.
► The analysis represents the establishment of a basis for assessing the performance of textured pivoted bearings.
► The work shows that texturing common pivoted bearings is not cost-effective.