The newly developed plastic segment cage offered by Schaeffler Group Industrial (INA/FAG) is designed to improve the economic efficiency and output of wind turbines having rotor supports according to the so-called single bearing concept. Schaeffler Group Industrial will present its new bearing cage design for the first time at HusumWind 2008 in Hall 4, Booth E10.

Currently there is a strong trend towards single bearing concepts for wind turbines since these carry less weight and require less installation efforts. The rotor head in such designs is directly bolted, for example, to the bearing outer ring so that the need for a shaft is eliminated. To date it is mainly double row tapered roller bearings with pin-type steel cage that are used for single bearing concepts. The rolling element riding bearing cage gives high stability and service long life. However, the through-boring of the rollers involves relatively high manufacturing efforts.

Higher efficiency
Schaeffler Group Industrial has therefore developed a new plastic segment cage especially for use in single bearing applications. The cage consists of single segments that are connected to each other via snap fittings. This lock ensures a defined clearance which enables the uniform expansion of the bearing cages. High-strength and lightweight PEEK is used as cage material. It can accommodate high loads while offering excellent wear resistance. Moreover the plastic segment cage reduces friction and thus increases wind turbine efficiency. The new cage design improves not only rolling element guidance, but also enables optimum lubricant supply.