Successful qualification for series production: Liebherr and Senvion introduce three-row roller bearings as a new blade bearing design

After a successful cooperation of meanwhile more than 15 years, Liebherr and Senvion, one of the leading manufacturers in the wind segment, have developed a new blade bearing design. Following a total development time of 14 months and a thoroughly planned validation process, the product is now ready for serial start-up at Liebherr-Components Biberach GmbH.

To support the continuous and successful development of wind turbines, the installed components have to be optimised in terms of load and lifetime requirements. Already in 2009, Liebherr recognised the potential capacity limitations of the standard four-point ball bearing for blade adjustment systems. From then on, new concepts have been intensively carried out within the framework of a research project. As a result, Liebherr has introduced three-row roller bearings as an alternative solution for the pitch system to its customers.

After a concept study in 2014, Senvion chose Liebherr as the main development partner. It was agreed to enter into a collaboration focusing on the implementation of a three-row roller bearing for the pitch system of the new Senvion 3.XM Eco Blade Control (EBC) turbine platform. The development project included multiple design studies and calculation cycles as well as large-scale tests. After a total development time of 14 months and a thoroughly planned validation process, the new bearing is now ready for serial start-up.

"By implementing a three-row roller bearing from Liebherr, we were able to significantly increase the overall pitch performance at optimum dimensions and to implement an intelligent load management system", said Felix Mund, Design Engineer from Senvion. "Moreover, the three-row roller bearing delivers the right answer with regard to extended life time requirements. As opposed to the currently standard 20 years, our customers now expect a service life of over 25 years."

Both Senvion and Liebherr are highly satisfied with the positive results of the cooperation. "It proves that higher technical requirements and challenging cost targets are moving in the right direction, if customers and suppliers join their forces to develop new products", summarises Oliver Wennheller, Sales Director Wind Energy at Liebherr Components.