There are different elements in machines, bearings being one of them, which allow the movement of the machine components along each other. Bearings are an important integral part of any object, to emphasize this, bearings support sky scrapers during earthquakes by offering them some movement. In fact even human beings whose joints involve sliding contact bearings, would come to a stop if they stop working. Duplex bearings are pair of two matched bearings. The duplex bearing pair provide better shaft location with enhanced accuracy. They are also used to increase the stiffness and thereby the capacity of the bearing assembly. This also enhances the bearing position in both axial and radial directions and the load bearing capacities. The axial and radial load bearing capacity is highly increased unlike that in single bearings. These matched bearing pairs have their outer or inner rings relieved selectively by precise amount called preload offset. During installation, when the...