Degradation of a geared bearing of a stacker

Large size rolling-element bearings used for turning of upper body of machines used in open-pit mining are made in form of single-row or double-row ball bearings. Section diameter of those bearings may be as large as 20 m and rolling elements have diameters of 100 to 250 mm, while they are under eccentric axial load from few to tens of MN. Due to low stiffness of supportive elements and its non-uniform presence all over the circumference of the bearing, the load upon rolling elements is rather unequal in those bearings. The flow of load stream concentrates in points which are in the areas with highest stiffness. This may be achieved using modern computer-assisted design tools. The specificity of these custom made machines makes obtaining credible data for numeric models possible only by applying analyses of the already existing bearings and their support structures which had been in operation for many years. Was introduced applied to opinion of effect of long-lasting exploitation on change of parameters of bearing.