Analysis of plastic hole expansion under gear interference fit
WEN Chao
GU Jianfeng
ZHANG Hong
LI Zhengminqing
HUANG Bo
Abstract：[Objective]In the locomotive transmission system,the gear-shaft interference fit is prone to plastic hole expansion under long-term meshing impact and residual stress relaxation,leading to a reduction in interference magnitude and potential safety hazards.Therefore,it is crucial to reveal the plastic hole expansion mechanism of gear interference fits.[Methods]Aiming at the plastic hole expansion phenomenon of gears,based on the established shaft-hole interference fit model,the allowable interference magnitude for shaft-hole interference fit was calculated.A mathematical model describing the variation of plastic deformation with cyclic load was established,the influence law of shaft-hole force on interference magnitude under interference fit was analyzed,and the effect of residual stress on the stress distribution of gear inner hole was investigated.On this basis,test pieces were designed,and gear plastic hole expansion tests were carried out.[Results]The results show that the maximum force is borne on the interference fit surface,and the forces on the gear and shaft increase with the increase of interference magnitude.Residual stress causes significant changes in the radial and axial distribution of stress inside the gear.The principle-based tests conducted verify the accuracy of the theoretical prediction model for plastic hole expansion under shaft-hole interference fit.
Keywords：Residual stressGear interference fitPlastic hole expansion
Publication Date：2025-09-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：10( 102-111 )