Self-Aligning Ball B. SKF 1218 K/C3

The SKF 1218 K/C3 double-row self-aligning ball bearing, with a tapered bore and increased C3 clearance, compensates for misalignment caused by shaft deflection in the dimensions 90x160x30 mm.

This open SKF 1218 K/C3 self-aligning ball bearing is suitable for industrial applications involving misalignment. Thanks to the hollow-spherical outer ring raceway, the two rows of balls self-align during operation. The sheet steel cage guides the rolling elements at temperatures ranging from –30 to +150 degrees. The component, made from 100Cr6 rolling bearing steel, complies with tolerance class P0/PN or ABEC 1 and accommodates radial forces.

In which applications does the 1218 K/C3 self-aligning ball bearing compensate for misalignment?

Design engineers and maintenance personnel use this self-aligning bearing primarily on long shafts where manufacturing-related misalignments or load-induced deflections occur. The double-row design compensates for angular misalignment between the inner and outer rings without increasing frictional resistance. Typical applications can be found in general mechanical engineering as well as in bearing arrangements with elastic shaft deflection. The open design allows for flexible lubrication with oil or grease via the surrounding housing structure.

What is the function of the 1:12 tapered bore and the C3 clearance?

The suffix ‘K’ denotes the tapered bore with a taper ratio of 1:12. This design facilitates mounting on tapered shaft seats or, using suitable mounting and withdrawal sleeves, on cylindrical shafts. The increased C3 bearing clearance compensates for the expansion of the inner ring during mounting. At the same time, this clearance provides thermal reserves to accommodate temperature differences between the inner and outer rings. During assembly, care must be taken to adjust the remaining operating radial clearance accurately.