Four Point Contact B. FAG QJ228 -N2-MPA

The QJ228 -N2-MPA four-point bearing from FAG, measuring 140 x 250 x 42 mm and featuring a brass cage and retaining grooves, offers a robust solution for axial forces acting in both directions.

The QJ228 -N2-MPA four-point bearing from FAG Rolling Bearings is primarily designed to accommodate high axial forces from both directions whilst requiring minimal axial installation space. Thanks to the specific raceway geometry, the rolling elements make defined contact with the rings under load, which supports precise guidance of the shaft. As an open bearing with a brass cage, this design is suitable for operating temperatures ranging from –30 to +200 degrees Celsius. It is manufactured to standard tolerance P0/PN or ABEC 1 with standard radial clearance.

In which applications does the QJ228 -N2-MPA four-point bearing prove its worth?

It is primarily used where high axial forces occur in varying directions and where double-row bearings would require too much axial installation space. Typical applications include gearboxes or combined bearing arrangements in general mechanical engineering, where a separate radial bearing absorbs the transverse forces. As it is designed as a pure or predominantly axial bearing, the construction guides components in the longitudinal direction, provided the outer ring is mounted radially free within the housing.

What is the function of the split inner ring and retaining grooves?

The two-piece inner ring allows a large number of rolling elements to be accommodated, which increases the axial load-carrying capacity of the bearing arrangement. Furthermore, this design facilitates assembly, as the outer ring and the two halves of the inner ring can be fitted separately onto the shaft and housing. The two retaining grooves in the outer ring, offset by 180 degrees, serve to prevent rotation within the housing. Matching retaining pins engage with these grooves and secure the outer ring against rotating with the shaft under varying load conditions.