Lifetime extension of gears and main bearings in wind turbines, scientific calculations and practical implementation

Abstract

REWITEC, as a part of Cargill Bioindustrial, is a developer and manufacturer of an innovative particle-based surface treatment phyllosilicate-technology for increasing the reliability and the lifetime of wind turbine gears and bearings. The active particles are compatible to all common oils and greases and use lubricants as a carrier to build through their adsorption a protective and repairing phyllosilicate-based coating on the surface. The modified surface has a significantly lower surface roughness, which ensures a better load distribution, lower local pressure and lower tribological stress. Additionally, due to the special layered material structure the particles can be sheared in the tribological contact, which leads to a reduction in friction. All in all, when applying the products systems can run better with reduced friction, wear, surface roughness and temperature. These effects lead to higher reliability and a longer lifetime and thus to cost savings for operators. We would like to show our new scientific study about the lifetime calculation of a grease-lubricated wind turbine main bearing (1.5 MW) with and without the use of technology. The project is a cooperation between REWITEC and Sentient Science who performs lifetime calculations using digital clone method based on real friction coefficient and surface roughness data. The project includes data generation using MTM test bench, in a wind turbine bearing and subsequent simulation based on this data and bearing geometry. The simulation shows that with REWITEC the probability for a bearing failure significantly decreases which leads to a lifetime extension of up to 17.3 years.