Rolling bearings are already one of the most precise machine elements with the standard accuracy PN, or earlier P0. The accuracy is defined by dimensional and shape deviations of the rolling bearing rings; but ripples and surface qualities of the bearing raceways and rolling elements also play a decisive role in high-precision bearings.
The area of high-precision bearings begins, by definition, beyond the already clearly restricted P5 tolerance class and usually includes the tolerance classes P4, P4S, P2, P2S and SP. For special requirements, our engineers define special tolerances, that restrict exactly those tolerances that are necessary for the bearing.
There are various reasons for using high-precision bearings from an application engineering perspective. These are most common in the machine tool sector. Spindles as well as rotary and swivel tables must achieve perfect radial and axial run, since the machining quality of the workpieces to be machined is directly related to the running accuracy of the rolling bearings. The speed suitability of a rolling bearing is also directly increased by the accuracy of the rings and rolling elements.
Less well known is that high accuracies are also required in other applications and are also available as standard from KRW. Particularly in the case of highly loaded multi-row or paired bearings, the permissible form and position deviations of the bearing components are restricted to a few micrometres in order to ensure the full load-bearing capacity of the bearings. Examples of this are support roller bearings in Sendzimir mill stands, multi row cylindrical roller bearings for support rollers or paired cylindrical roller bearings for the planet in planetary gears. Basically, KRW is an application specialist. Even with prototypes and small series, KRW is able to manufacture any design in special tolerances far below the standard tolerance classes.