Support reaction model of multi-stage gear bearing in shearer cutting section

Bearing is a standard part widely used in all kinds of mechanical equipment, and it is the key component to realize relative rotation of different components in the equipment. Roller bearing is used in shearer cutting transmission system. Its support stiffness changes with the load and has nonlinear characteristics. It is very complicated to calculate the stiffness of bearing theoretically. In this paper, the nonlinear support force model of bearing is established by using the data from romax’s standard bearing library.

(a) Displacement load relationship (b) Displacement angular stiffness relationship

Taking the bearing of the first stage gear at the high-speed end as an example, the specific steps of establishing the bearing support reaction model are introduced. Firstly, the model of the first stage bearing is SKF nj228ec / C3, and the shafting component model including shaft and bearing is established in romax. Then, when the rated power of the cutting transmission system is calculated, the load of the bearing is 33.185kn, and 58 simulation loads are taken at different intervals within the range of 0.01 ~ 5 times of the load to load the shafting model, and the original data of radial deformation and angular stiffness under different loads are obtained, as shown in the figure. Finally, the interpolating function interp1 in MATLAB is used to calculate the load and angular stiffness under any radial displacement. Due to the bearing clearance, the abscissa of the starting point of the curve in the figure is 54.6 um.