Arbitrary matching bearings are specially manufactured, so that when arbitrarily arranged and installed close together, a certain internal clearance or preload and/or uniform load distribution can be obtained without the use of gaskets or similar devices. Any pair of bearings has a model suffix to indicate internal clearance (CA, CB, CC) or preload (GA, GB, GC).
When the load capacity of single row bearings is not enough, use paired installation (tandem configuration); or when the load is a composite load or axial load acts in two directions, use paired installation (back-to-back and face-to-face pairing).
When the load line is in series configuration, the radial and axial loads are evenly shared by the bearing. However, the bearing assembly can only bear axial loads acting in one direction. If the axial load acts in the opposite direction, or if there is a compound load, a third bearing adjusted relative to the tandem paired bearing must be added.
The load lines of the bearings that are paired back to back are separated to the bearing shaft. It can bear axial loads acting in two directions, but the load in each direction can only be borne by one bearing. Bearings mounted back-to-back provide a relatively rigid bearing configuration and can withstand overturning moments.
The load lines of the facing paired bearings converge toward the bearing shaft. It can bear axial loads acting in two directions, but the load in each direction can only be borne by one bearing. This configuration is not as rigid as the back-to-back pairing and is not suitable for withstanding overturning moments.
There are also advantages when the universally matched bearings are used in conjunction with a single bearing. Most of the bearings are of the SKF Explorer series, so they have higher accuracy, load capacity and higher speed.