Influence of cylindricity and surface modification on load bearing ability of interference fitted assemblies

This paper presents the influence of cylindricity and surface modification on load bearing ability of interference fitted assemblies. Assemblies were made of EN 8 steel with and without (plain) nubs. The influence of cylindrical profile or waviness of pins, with and without nubs on load bearing ability is analyzed by experimental and harmonic analysis. Results show that pins with nubs can carry higher load and pins with and without nubs having harmonics of smaller amplitude can carry higher load for a given interference. Also, increase in average undulation number increases the load bearing ability. Further, finite element method (FEM) was used to evaluate the Von Mises stresses on the performance of interference fitted assemblies. An appropriate finite element model was developed to analyze the pattern of contact stresses in interference fitted assemblies for with and without nubs with varying interference. The results reveal that pins with nubs can with stand higher stresses.

► Interference fitted assemblies with pins having nubs exhibit higher load bearing ability.
► Cylindricity error does not produce definite pattern on load bearing ability of interference fitted assemblies.
► Lower harmonics in general and third harmonic in particular influence on load bearing ability.