Considerations for increasing the durability of the main shafts bearings of wind turbine

Abstract

The novelty in this work consists in the identification of constructive solutions for bearing the main shaft with mounting in three and four support points. Improvements to the existing bearing construction solutions for existing turbines are also presented. As the bearings perform their function, which is essential to the mission inside the current turbines, with MW installed powers, dynamic stresses and unpredictable stresses lead to costly premature repairs. For the benefit of the wind industry, the reliability of the main shaft bearings needs to be improved. ^{[1], [2], [3]} The market demand motivates the development of new technical solutions for the replacement of standard radial thrust roller bearings in three-point bearing turbines, such as wear-resistant radial roller bearing roller bearings and two-row radial tapered roller bearings, pre-stressed ^[4]. For this reason, this work presents some constructive solutions that are efficient in the wind turbine industry. Also, there are presented some mode of failures, like: the incipient stages of micro exfoliation of the working surfaces of a two-row radial roller oscillating roller bearing in the main shaft of a wind turbine, insufficient lubrication, the simulations of different stages of distributions of pressure on inner and outer rings, equivalent (von Mises) stresses and an another improved construction solution of bearings.^[4] In conclusion, the criteria for choosing the types of reliable wind turbines imply a special attention in choosing reliable bearing elements, with long operation times and as few repair / maintenance costs as possible. ^{[5], [6]}