On the Relationship Between Journal Misalignment and Web Deflection in Crankshafts

Abstract

To characterize the severity of misaligned journal bearings, two independent parameters are needed: degree of misalignment and misalignment angle. These parameters are routinely used to predict the behavior of steadily loaded bearing. However, in the case of dynamically loaded bearings, the associated measurement of these parameters becomes much more complex. It is shown that the local crankshaft deflection can be obtained from the rigid body motion of the main journal with computed deflection angles. A model is developed which provides a relationship between the web deflection and crankshaft deflection. It enables one to conveniently characterize the severity of misalignment by measuring web deflection.