When the motor bearing bears too much static load or shock load at very low speed, the contact surface between the rolling element and the raceway will produce local permanent deformation. The amount of deformation increases with the increase of the load. If it exceeds a certain limit, the normal rotation will be affected. The basic static load rating is the static load that causes the contact stress calculated below to be generated at the center of the contact surface between the rolling element and the raceway that receives the maximum load. Self-aligning ball bearings..4600M {469kgf/}Other ball bearings..4200M {429kgf/}Roller bearings.4000M {408kgf/}The total permanent deformation of rolling elements and raceways under these contact stresses is approximately 0.0001 times the diameter. The basic static load rating of the radial bearing is called the radial basic static load rating, which is represented by Cor. In the following cases, the bearing size should be selected according to the static load rating, not the dynamic load rating. 1) The bearing is stationary and under the action of continuous or intermittent shock load; 2) The bearing is under load The rotating speed is less than 10rpm; or only a very short bearing life is required, and the selected bearing may be seriously overloaded according to the rated dynamic load; 3) The bearing is rotating, but it needs to withstand a lot of The heavy shock load equivalent static load is an imaginary load. When the bearing is stationary or the rotation speed is extremely low, the center of the contact surface between the rolling element and the raceway that bears the maximum load under the imaginary load produces the same contact stress as under the actual load condition. The equivalent static load of the radial bearing adopts the radial load passing through the center of the bearing. (27) P0＝0.6Fr＋0.5Fa[KN] When Fa/Fr＞0.8 (28) (2) Calculation of equivalent static load of cylindrical roller bearing: P0＝Fr[KN] (29) (3) Spherical roller Calculation of the equivalent static load of the bearing: Calculate from the following two formulas, take the larger value (30) a u003d or P Fr +Y0FPoru003dFrFa: axial load, the value of Y0 in the KNY0 radial static load coefficient formula can be found Bearing dimension table. (4) Calculation of equivalent static load of angular contact ball bearing: single row angular contact ball bearing with contact angle of 15, single bearing or series configuration P0u003d0.5Fr+0.46Fa [kN] (31) When F0