Bearing Rollers

Description:

This is a case of small bearing rollers collected by the Anti-Friction Bearing Manufacturers Association for a public relations exhibit during the early 1950s that was donated to the museum in 1977. For optimum bearing performance, rollers in a bearing must be exactly uniform size. If not, the bearing’s load will focus on the irregular roller, leading to failure in the bearing. Rollers are manufactured by a “cold heading” process. In cold heading a piece of cylindrical steel wire is cut, then pressed through a die to taper the ends. The rollers then go into a grinder to remove the protrusions created by the heading process. Further heating, grinding, and cleaning leaves uniform rollers ready to be added to its matching cage or raceway to make a fully assembled bearing.

Simple bearings have been used for thousands of years reducing friction on turning parts like the axles of carts. In the late 1800s and early 1900s advances in machining and production expanded bearing use in all types of machines greatly increasing their life and precision. Bearings reduce friction on turning surfaces and keep them running true. Bearings come in a variety of shapes and sizes (including ball, roller, tapered, and simple friction). Modern bearings are often set in an inner and outer ring (called a race) sometimes with cages (separators) spacing the bearings. Changes to the size, shape, alignment, race, and cage allow for bearings to be used in almost any industry—from industrial turbines and automobiles to household mixers and computer hard drives.