Finite-element modeling of the failure of interference-fit planet carrier and shaft assembly

A planet carrier and shafts assembly with interference-fit was modeled based on 3-D finite element method by applying thermal loads to the shafts with orthotropic coefficients of thermal expansion. A 3-D finite element contact model verified that the contact pressure is identical compared with the calculated pressure by Lamé's equations for the thick-wall cylinder interference-fit. A displacement history analysis by the 3-D finite element multi-contact simulation under alternate loads reveals the root cause for the interference-fit shafts coming out of the planet carrier after 65 h of planetary gear reducer working test.