Four Point Contact B. SKF QJ316 N2MA/C3

The SKF QJ316 N2MA/C3 four-point bearing (80x170x39 mm) accommodates high axial forces in both directions whilst requiring minimal axial installation space.

This open four-point bearing, the QJ316 N2MA/C3, is manufactured by SKF Rolling Bearings and has a bore of 80 mm, an outer diameter of 170 mm and a width of 39 mm. The design is essentially that of a single-row angular contact ball bearing, but features raceways capable of withstanding axial forces in both directions. The rolling bearing is manufactured to standard tolerance P0 or ABEC 1 and is designed for operating temperatures ranging from -30 to +150 degrees.

What is the QJ316 N2MA/C3 four-point bearing suitable for in operation?

This design is primarily used where pure or predominantly axial loads occur with varying directions of action. The bearing often functions as a pure axial bearing, whilst a separate radial bearing absorbs the radial forces. The split inner ring allows the assembly to be disassembled during installation, which facilitates the pressing onto and joining of the individual components onto the shaft. The brass cage guides the rolling elements and is suitable for demanding thermal conditions.

What is the function of the retaining grooves and the C3 clearance?

The suffixes N2MA and C3 indicate two functional design features. Two retaining grooves in the outer ring, offset by 180 degrees, allow the bearing to be secured in the housing against unintentional rotation using retaining pins. The designation C3 indicates a slightly increased radial clearance compared to the standard. This increased clearance compensates for temperature- or fit-related expansion during operation, ensuring that the rolling elements continue to roll without stress even when heated. As this is an open bearing, lubrication is provided by the surrounding housing system.