By using the generalized cumulative model of wear and a developed rapid method for the investigation of the kinetics of tribocontact interaction in a plain bearing with small ovality of the shaft, we evaluate the accuracy of evaluation of the service life. We study single-zone and single-double-single-zone contact interactions of the shaft with the bush. The obtained results are thoroughly analyzed and the influence of the parameters of the interval-block main scheme and modified computational scheme on the accuracy of evaluation of the service life of the bearing is estimated. We establish the regularities of decrease in the accuracy of the solution depending on the sizes of the blocks of interaction cycles with constant conditions and on the interval of discretization of the contour of the shaft. The schemes of calculations optimal from the engineering point of view and their parameters are indicated.Keywords: plain bearing, generalized cumulative model of wear, service life, rapid method for the investigation of the kinetics of wear, accuracy of the method, interval-discrete and interval-block tribocontact interaction.The methods for the numerical analysis of plain bearings [1-6] are based on the assumption that their contacting components have circular cross sections (Fig. 1). However, it is known that, in the process of manufacturing of shafts and bushes, their contours inevitably get certain small deviations from the circular shape of various types. The simplest of these deviations is ovality. In this connection, it is necessary to take into account the influence of technological noncircularities on the parameters of contact and tribocontact interactions.In the cumulative model of wear developed in [7], the kinetics of tribocontact interactions in plain bearings with noncircular shafts and bushes was investigated according to the interval-discrete scheme. This model is based on splitting the contour of the shaft with deviations from the circular shape into j intervals of discretization Δα 2 = 1°, 5°, 10°, … , 90°. In each of these intervals, the parameters of tribocontact interaction remain unchanged within a single revolution of the shaft and, in the course of subsequent revolutions, the characteristics of contact vary as a result of wear of the components of bearings. Moreover, the linear wear is cumulated. By using this model, the solutions of this problem were obtained for the case of realization of the single-zone contact of the components in [7][8][9].However, the interval-discrete scheme of tribocontact interaction requires long time for calculations, in particular, for small intervals of discretization of the contour of the shaft, when the solution is most exact. As Δα 2 increases, the accuracy becomes lower, and the time decreases proportionally to the increase in Δα 2 .