Measurement of Partial Slip at the Interface of a Shrink Fit Assembly under Axial Load

The slip at the interface of a shrink fit between a shaft and hub under axial load has been measured by a technique where a small cross hole is drilled through the assembly and a Talysurf profilometer is used to measure the profile of the hole. The measurements suggest that the technique is capable of measuring slip of the order of 1 to 2 μm. A finite element study has been carried out to predict the magnitude of slip with adequate agreement with the experimental results. The finite element study also shows that the extraction load for shrink fit assembly does not increase linearly with the coefficient of friction or the axial length of engagement of the shrink fit, as would be expected from a straightforward analysis.