Wind main bearing: new single-row tapered roller bearing

With the new type of main bearing for wind turbines a fresh wind is literally blowing in Liebherr's components product segment. For the first time, Liebherr develops and produces a main bearing arrangement, consisting of two single-row tapered roller bearings. Optimum rolling characteristics and ideal force distribution are ensured by the layout and design of the bearing. In addition, the precise rolling elements combined with the narrow manufacturing tolerances of the two single-row tapered roller bearings provide for an exact preloading in the installed condition. Liebherr ensures that the preload is determined during development by finite element calculations, as well as by the dimensional accuracy of the machines in production. The two single-row tapered roller bearings thus enable ideal load distribution.

High complexity in production: inductive hardening process and superfinishing

"Setting the filigree rings in the slip-free hardening process was a challenge," explains Stefan Milotzke, head of technical sales of the business unit slewing bearings at Liebherr in Biberach (Germany). "Our several years of experience enable us to make a perfectly coordinated adjustment of the four inductors. This is particularly important, because it enables us to meet the high requirements put on the hardening depth and surface hardness," says Milotzke. Superfinishing further refines the raceway surface: In this process, the surface of the raceway is processed in such a way, that wear, friction and lubrication are optimised. This ensures extremely high surface quality and a longer component service life.