Four Point Contact B. FAG QJ218 -N2-MPA

The FAG QJ218 -N2-MPA four-point bearing, measuring 90 × 160 × 30 mm, accommodates high axial forces in both directions whilst saving space.

The QJ218 -N2-MPA four-point bearing is an open, single-row radial ball bearing of standard tolerance class P0/PN (ABEC 1). The design features a split inner ring and a robust brass cage. This rolling bearing is particularly suitable for applications where axial forces act in both directions and the axial installation space is insufficient for double-row bearings. The permissible temperature range is from -30 to +150 degrees Celsius.

What loads can the QJ218 -N2-MPA four-point bearing accommodate?

The roller bearing primarily accommodates alternating axial loads with low radial loading. The component is often combined with a separate radial bearing as a pure axial bearing to provide axial guidance in confined spaces. In axial operation, the balls contact the raceways of the inner and outer rings at two points and transmit axial forces directly. Thanks to its open design without sealing washers, the bearing can be supplied directly with oil or grease via a central circulating lubrication system.

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

The split inner ring allows the outer ring and ball cage to be mounted separately from the inner ring halves. This makes installation on the shaft and in the housing straightforward. The suffix N2 indicates two retaining grooves on the end face of the outer ring, offset by 180 degrees. These recesses are used to secure the outer ring against rotation in the housing by means of retaining pins, should the bearing be used as a pure thrust bearing with radial clearance.