Basic dynamic load rating, C
The basic dynamic load rating, C, is used for calculating basic rating life and SKF rating life for bearings that rotate under load. The C value is defined as: the bearing load that will result in an ISO 281 basic rating life of 1 000 000 revolutions. It is assumed that the load is constant in magnitude and direction and is radial for radial bearings and axial, centrically acting, for thrust bearings.
The basic dynamic load ratings for SKF bearings are determined in accordance with the procedures outlined in ISO 281, and apply to bearings made of chromium bearing steel, heat treated to a minimum hardness of 58 HRC, operating under normal conditions.
Dynamic load rating for SKF Explorer bearings
SKF Explorer bearings have undergone design, material and manufacturing improvements that require adjusted factors to calculate the dynamic load ratings in accordance with ISO 281. The SKF Explorer adjusted dynamic load ratings, which are higher than the ratings for SKF basic design bearings, are verified by extensive endurance testing.
To fully utilize the improved performance of SKF Explorer bearings, the SKF rating life calculation including the life modification factor aSKF is recommended. In fact, it is the modified rating life of the bearing, L10m, rather than the dynamic load rating, C, that provides the most valuable information regarding the endurance performance of a bearing. For more details → Life modification factor, aSKF.