These balls are often used in bearings. Tight-Tolerance Hard Wear-Resistant E52100 Alloy Steel Balls. The diameter on these balls is held to a precise tolerance. Low-Carbon Steel Balls. Also known as mild steel, use these low-carbon steel balls in parts that don't require high strength.

Ball bearings, or deep-groove bearings, extend the working life of equipment by enabling wheels, pulleys, and other rotating parts to reduce friction and move smoothly. Ball bearings have a series of round balls encased in a housing and support high axial or low-to-moderate radial loads. Axial (thrust) bearings support loads parallel to the axis, such as those exerted by a table supporting a weight.Ball Bearings. Ball bearings reduce friction between shafts and axles and carry radial loads, thrust loads, or a combination of both. They contain an outer ring, inner ring, and a cage that holds and spaces bearing balls, the bearing's spherical rolling elements. These bearing balls must be perfectly rounded and spaced to prevent friction and bearing failure.