Ball Bearing
date: label: date made
content: 1950
notes: label: Description
content: The Torrington Company of Torrington, Connecticut manufactured this sealed bearing ring during the 1950s. Sealed bearings were often used in aircraft or other adverse conditions where exposing the bearing to the elements would lessen its effectiveness. The bearing is inscribed “4DR9.” The Anti Friction Bearing Manufacturers Association collected bearings for a public relations exhibit during the early 1950s, and donated them to the museum in 1977.
label: Description
content: 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.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Mechanical and Civil Engineering
label: See more items in
content: Bearings
label: See more items in
content: Industry & Manufacturing
creditLine: label: Credit Line
content: Anti-Friction Bearing Manufacturers Association
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MC.336099.16
label: accession number
content: 1977.0585
label: catalog number
content: 336099.16
objectType: label: Object Name
content: bearing
physicalDescription: label: Physical Description
content: steel (overall material)
label: Measurements
content: overall: 1/2 in x 5/8 in; 1.27 cm x 1.5875 cm