The use of the outer spherical bearings assembly with a seat simplifies the peripheral structure of the machine, thus making installation and maintenance more reasonable .Moreover, due to its centrality, it can prevent the torque load caused by the installation error, and it is easy to be installed on the machine and the side wall, so it can be used in all places such as the frame structure Because of the above characteristics, the application field of the spherical bearings assembly with the seat can be expanded rapidly. At the same time, it also requires us to have a variety of products with various performance