Calculation of BushinglConnecting Rod Press-Fit Working Envelope

A bushing bearing was required between the aluminum connecting rod and the wrist pin to reduce wrist pin bearing wear in a severe application. The bushing could not be machined after assembly and precise control of bearing clearance was achieved by re-sizing (using a mandrel) after assembly. Re-sizing was a critical operation. Too much re-sizing would loosen the bushing pressfit while too little re-sizing would result in undesirable bearing clearance. A non-linear finite element analysis was pertormed to provide guidelines and recommendations on press-fit and re-sizing dimensions.