Whether agitators in the process industry, engine gearboxes, aircraft turbines or analysis equipment in medical laboratories: Whenever ball bearings come into contact with chemicals, there is a risk of corrosion and premature failure. "Classic metal ball bearings in particular are susceptible to corrosion under these conditions. Ball bearings made of polyether ether ketone (PEEK) also quickly reach their technical limits in applications with chemical contact in conjunction with higher speeds and loads, especially when a long service life is required," says Marcus Semsroth, Head of the xiros polymer ball bearings business unit at igus. "We have developed new ceramic ball bearings from the xiros series to offer designers greater safety and increase the service life and efficiency of their applications. They are resistant to chemicals and at the same time many times more durable than standard PEEK bearings." The bearings are now available in three DIN dimensions with inner diameters of 8, 10 and 12 millimetres. Other dimensions are available on request.
Laboratory tests prove high wear resistance
The reason for the longevity of the new bearings is a special combination of materials: the inner and outer races and the balls are made of technical ceramics. The cage that holds the balls in position is a PEEK-based material developed by igus. "Tests in our in-house laboratory have shown that, thanks to this combination of materials, the ball bearings are 65 times more wear-resistant than counterparts made entirely from PEEK," explains Marcus Semsroth. Further advantages: The new ceramic bearings are around 40 percent lighter than metal bearings, which means that energy efficiency is improved, especially at high speeds. They are also maintenance-free, as they do not require lubricants for their low-friction dry running. Another advantage for the safety of many applications, such as electric motors, is the fact that the ceramic bearings are neither magnetic nor electrically conductive.
Specially developed for high speeds
igus offers the ceramic bearings in two versions: Both are suitable for applications where high temperatures and high speeds are crucial - such as aircraft engines, gearboxes and medical devices. The bearings are particularly resistant to chemicals in alkaline environments. The bearings made of white zirconium oxide are tougher and more resistant to corrosion. They are also cheaper than the black version made of silicon nitride, which is somewhat more brittle. The silicon nitride ball bearing, on the other hand, has a particularly high thermal stability. This makes it suitable for superheated steam applications and applications with rapid temperature fluctuations. "The silicon nitride variant is therefore the preferred choice for industries such as aerospace. Zirconium oxide, on the other hand, is ideal for use in chemical plants, medical devices or the food industry," says Marcus Semsroth, summarizing the advantages of the two new ceramic ball bearings.
Find more information on the new ceramic ball bearings here!