Arc Systems Posted May 30, 2012 In the old days, a pair of taper roller bearings were used, these had separate outer races that were a press fit in the hub/brake drum, the castellated nut was then adjusted and pinned to hold the taper bearings at the correct clearance. Today, what's called the 'preloaded bearing' is pair of plain roller bearings with a spacer between, this assembly is pressed into the hub as a complete pre-assembled unit, the outer race an interference fit in the hub. The inner race of the bearing is a slide fit on the stub axle so a 'preload' pressure applied to clamp the inner race so it cannot spin on the axle, this forcing the bearing to act as it should and the whole assembly revolve on the ball bearing within the two races. Which bring us to the 'one shot nuts' which in the case of caravans, are actually 'elliptical lock nuts', googling same will explain their application, particularly their designed with unlimited re-use?! http://en. wikipedia. org/wiki/Distorted_thread_locknut Quote Share this post Link to post Share on other sites
Gav74 Posted May 31, 2012 In the old days, a pair of taper roller bearings were used, these had separate outer races that were a press fit in the hub/brake drum, the castellated nut was then adjusted and pinned to hold the taper bearings at the correct clearance. Today, what's called the 'preloaded bearing' is pair of plain roller bearings with a spacer between, this assembly is pressed into the hub as a complete pre-assembled unit, the outer race an interference fit in the hub. The inner race of the bearing is a slide fit on the stub axle so a 'preload' pressure applied to clamp the inner race so it cannot spin on the axle, this forcing the bearing to act as it should and the whole assembly revolve on the ball bearing within the two races. Which bring us to the 'one shot nuts' which in the case of caravans, are actually 'elliptical lock nuts', googling same will explain their application, particularly their designed with unlimited re-use?! http://en. wikipedia. ..._thread_locknut A very clear and easy to understand explanation. Thanks. Quote Share this post Link to post Share on other sites
