Technology

Materials

The demand for rolling bearings that are characterised by very high performance capability and operating life even under extreme conditions has increased significantly in recent years – not least because of the tightening of legal framework conditions, the growing awareness of sustainability and the drive towards energy-efficient, robust solutions. Schaeffler has been offering answers to these diverse requirements for many years.

 
The new thermally robust FAG cylindrical roller bearing TR
The new thermally robust FAG cylindrical roller bearing TR

Example: Ceramics
Through the use of ceramic rolling elements, which generate less friction, it is possible to achieve higher and higher speeds, which makes these new developments suitable in particular for aerospace applications as well as for machine tools. The robust nature of ceramic rolling elements can be seen clearly from the example of a spindle bearing: the new high performance spindle bearing series RS and the thermally robust cylindrical bearing TR combine very high speed capability with high load carrying capacity and resistance under a wide variety of operating conditions. Furthermore, the innovations have the effect of simplifying design and mounting as well as optimising lubricant distribution.

 
Fighting corrosion: a comparison after 24 hours in the salt spray test with the Corrotect® coating (left) and without coating (right).
Fighting corrosion: a comparison after 24 hours in the salt spray test with the Corrotect® coating (left) and without coating (right).

Example: Cronitect®
Cronitect® is a high performance corrosion-resistant steel developed by Schaeffler which allows rolling bearings to run under extreme conditions, for example in contact with corrosive media (water, acids, cleaning agents) or in dry running – either in a sealed version or without seals. Cronitect is a steel suitable for martensitic hardening which, due to its chemical composition, can be combined with a new thermochemical surface hardening process to give very high hardness with very high corrosion resistance. Cronitect completes the salt spray test in accordance with DIN 50021 SS without any problems, even after 600 hours. Its corrosion resistance is thus several times better than that of conventional corrosion-resistant steels.

 
The FAG Cronitect® hybrid bearing for inline skates offers excellent smooth running characteristics and is practically maintenance-free.
The FAG Cronitect® hybrid bearing for inline skates offers excellent smooth running characteristics and is practically maintenance-free.

Example: Hybrid rolling bearings
Schaeffler also has convincing innovations in the sports sector: smooth running characteristics, low friction and corrosion resistance make the new Cronitect® hybrid rolling bearing the first choice for inline skaters and for bottom brackets on premium racing cycles. This is made possible by the materials combination of bearing rings made from the high performance steel Cronitect® we have developed together with ceramics for the rolling elements, an optimised ball raceway geometry and an extremely low-friction sealing concept.