The speed limit is determined by criteria that include the form stability or strength of the cage, lubrication of cage guiding surfaces, centrifugal and gyratory forces acting on the rolling elements and other speed-limiting factors.
Experience gained from laboratory tests and practical applications indicates that there are maximum speeds that should not be exceeded for technical reasons or because of the very high costs involved to keep the operating temperature at an acceptable level.
Limiting speeds are shown in the product tables, and are based on the demands of high-speed applications; this has been taken into consideration for the bearing and cage designs shown in this catalogue.
It is possible to run bearings at higher speeds than those shown in the tables, but then running accuracy has to be considered, as does cage design, lubrication and heat dissipation. It is therefore advisable to contact the SKF application engineering service.
Further, additional aspects should be considered such as lubrication of the cage guiding surfaces and the shear strength of the lubricant, which are determined by the base oil and thickener, see section Grease lubrication.
For certain bearings, where the speed limit is not determined by heat from the rolling element/raceway contacts, only limiting speeds are shown in the product tables. These include, for example, full complement bearings and bearings with contact seals.
It should be remembered that if bearings are to function satisfactorily, at high speeds, they must be subjected to a given minimum load. Details can be found in the relevant product sections under the heading "Minimum load".