Angular Contact Ball B. SKF 3308 ATN9/C3

SKF double-row angular contact ball bearing 3308 ATN9/C3 with a 40 mm bore and an outer diameter of 90 mm, designed for combined radial and axial loads in both directions.

The 3308 ATN9/C3 double-row angular contact ball bearing, with its 30-degree contact angle, accommodates radial forces as well as axial loads in both directions. The open design, without integrated sealing washers, allows for direct lubricant supply via the surrounding housing system. Manufactured from standard rolling-element bearing steel (100Cr6), this design offers increased running accuracy to tolerance class P6 (ABEC 3). The lightweight polyamide cage guides the rolling elements with low noise and low vibration.

In which applications is the double-row angular contact ball bearing 3308 ATN9/C3 required?

This design is used in applications where bearing positions must be radially supported whilst being precisely guided axially in both directions. Functionally, the bearing corresponds to a paired set of single-row bearings in an O-arrangement, but requires less axial space. Typical applications include bearing arrangements subject to combined loads, as well as industrial applications with operating temperatures ranging from –20 to +120 degrees Celsius.

What do ‘C3 bearing clearance’ and a ‘polyamide cage’ mean in relation to this bearing?

The suffix C3 indicates a slightly increased radial clearance. This increased clearance compensates for operational thermal expansion between the inner and outer rings, thereby preventing mechanical stress during operation. The polyamide cage reduces the component weight and operating noise. During assembly, it should be noted that an external housing seal is required for the open rolling bearing to prevent the ingress of dirt.