Failure analysis for gear of gearbox in large wind turbine generator
LI Yanbiao
GU Shuchao
DUAN Peng
TANG Bin
Abstract：[Objective]Gearboxes account for the highest proportion of wind turbine failures,leading to the longest downtime of wind turbines and severely restricting the further improvement of wind power generation technology.In order to effectively address this issue,the analysis was conducted on the failure problem of the parallel intermediate stage broken gear of the 18CrNiMo7-6 gearbox in large wind turbines.[Methods]Firstly,the chemical composition and microscopic morphology of the fracture surface were analyzed by use of metal element analyzer,metallographic microscope and scanning electron microscope.Secondly,the mechanical properties were analyzed by means of tensile testing machine and impact testing machine.Finally,the design and operating environment were analyzed through the investigation and the reference of many related documents.[Results]It is found that the chemical composition,metallographic structure,mechanical strength,plasticity and toughness indicators conform to the relevant standards.The failure mechanism of gear is fatigue cracking that originates from the bottom of carburized layer.The non-metallic inclusion such as aluminium oxide is enriched on the sub-surface of gear teeth,producing local structural discontinuity and formation of stress concentration and fatigue source.
Keywords：Wind power generationGearboxFailure analysisNon-metallic inclusion
Publication Date：2025-10-31
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 125-132 )