Superfinishing of wind turbine main bearings further developed

The superfinishing process established in the rolling bearing industry has been further developed for wind turbine main bearings. It contributes to increasing the safety and efficiency of the main bearing rings used in wind turbines.

In view of the ever shorter development cycles for wind turbines and the parallel shortening of test phases, manufacturers are under enormous pressure. Simulations and complex models are increasingly replacing real tests, which increases the risk of failures, especially in the main bearings. As the main bearing is the central element of the drivetrain, the effects of a failure are particularly serious. It is the heart of the system and has to match the service life of the entire wind turbine. In addition, the continuing trend towards larger and more powerful turbines and growing competition on the global market are increasing the pressure on the industry.

The superfinishing process, also known as microfinishing, honing or short-stroke honing, has been established in the rolling bearing industry for decades. It is used to manufacture the individual bearing components - inner ring, outer ring and rolling elements - and produces precisely defined surface characteristics and structures. These ensure optimum tribological interaction between the bearing components. While the superfinishing process has long been standard in the production of spherical roller bearings and gearbox bearings, it has also become increasingly popular for rolling elements such as tapered rollers in recent years. However, its use in the production of bearing rings has so far been limited. In view of this challenge, the superfinishing process is now also relevant for larger tapered roller bearings and has been further developed across all industries.

The current market challenges make continuous further development of manufacturing technologies essential. For Supfina Grieshaber, a long-standing partner of the rolling bearing industry, this led to the development of the Supfina RacePro 4000. This innovative manufacturing solution transfers proven superfinishing processes to the machining of slewing bearings and combines stone finishing and belt finishing technologies in a single system. The newly developed workpiece drive concept increases efficiency and further optimizes the quality of surface finishing.

The use of qualified superfinishing processes in the production of rolling bearings contributes significantly to extending their service life. Transferring this technology to wind turbine main bearings is therefore a logical further development that significantly increases the reliability of these critical components. The current challenges on the market have clearly shifted the focus. Safety is now the top priority in order to remain competitive in the long term - without compromising on cost-effectiveness.

For Supfina Grieshaber, a reliable supplier and development partner to the international rolling bearing industry for decades, it was therefore an obvious choice to address this issue. After intensive development work, an innovative manufacturing solution for the surface finishing of rings for slewing bearings was created: the Supfina RacePro 4000. With this solution, proven superfinishing processes and the associated high quality standards from other industrial sectors can be transferred to slewing bearings. This is made possible by the use of stone finishing processes or a combination of stone and belt finishing. The process units of the Supfina RaceFlex 1600 series, which have been established for years, are used, supplemented by a newly developed, highly innovative workpiece drive concept.

The implementation of a qualified superfinishing process in the production of rolling bearings has a positive effect on numerous aspects of bearing function. A comprehensive description of all the benefits would go beyond the scope of a single article. But one thing stands out in particular: the significant contribution to extending bearing service life. This correlation has been proven across the entire range of standard industrial rolling bearings. It is therefore a logical step to transfer this proven technology to wind turbine main bearings. (OM-5/25)