Abstract: In order to open out the bonding accident mechanism occurring in the roll neck and sleeve of the oil-film bearing used on large-scale rolling mill, assembled with even interference for elastic joint, the contact stresses and its distributing during the hydro-bulging course of assembly are described quantitatively by the multiple boundary element method. The phenomena of localized contact stress concentration are presented at the two ends of the sleeve after assembling well to the roll neck is discovered. Therefore, the high stress zones corresponded with plastic deformation are presented at the surface of the roll neck because the maximum stress exceeds the yield limit. Using the rotating test set consisted of the cantilever shaft and sleeve by interference fit, the simulation experiments about fretting damage occurred in the roll neck and sleeve are performed under the rolling load. The mutual micro slippages are gen-erated at the ends of contact surface of the roll neck and sleeve, moreover, the mechanism that fretting damage leads to felt at the high contact stress zones between the roll neck and sleeve during the rolling course is discussed. So this sleeve structure, which is assembled with even interference for elastic joint, is not reasonable, and the primary viewpoint that the low quenching hardness caused bonding is negated.

Key words: Contact stress, Elastic joint, Fretting damage, Interference fit, Multiple boundary element method, Oil-film bearing