Determination of the Dynamic Load Capacity of Rolling Bearings Based on the Rated Torque of the Electric Machine

Abstract

The purpose of the article is to describe the method of calculating the dynamic load capacity of the most loaded bearing of an electric machine at the stage of electromagnetic calculation. The proposed method allows to initially determine the dimensions of such parts of an electric machine as bearings and bearing shields. The article considers the calculation of electromagnetic and mechanical parameters of an electric machine on the basis of the machine constant. The transition from the machine constant to the mechanical parameters of the bearing is carried out through the plot of radial loads (reactions) acting on the bearings. The dependences of the length of the shaft end on the permissible torque of the electric machine in accordance with GOST are given for different types of load, different strength and hardness of the shaft material. This technique connects the mechanical and electromagnetic parameters of the machine, allows to perform elements of mechanical calculation at the early stages of development. To simplify the calculation method, some relative geometric parameters are introduced, depending on the type and series or model of the electric machine. The load capacity of the most loaded bearing of the magneto-electric motor 11DVM160 for driving oil pumping machines is calculated. The initial data for the calculation were information from the design documentation, the results of computer modeling of the magnetic field, as well as test results. As a result of the calculation, the value of the dynamic load capacity of the most loaded bearing corresponding to the calculated mechanical load is obtained. In practice, the inverse problem may be relevant – determining the electromagnetic moment and power of the designed electric machine according to the bearing parameters limited by the specified initial dimensions of the machine.