Centrifugal castings are produced by pouring molten metal into a mold that is being rotated or revolved during the casting operation. The axis of rotation may be horizontal or inclined at any angle up to the vertical position. Molten metal is poured into the spinning mold cavity and the metal is held against the wall of the mold by centrifugal force. The speed of rotation and metal pouring rate vary with the alloy and size and shape being cast. Mold may be made of cast iron or steel, copper, graphite, ceramic, or dry sand. The outside surfaces of the casting or the mold surface proper, can be modified from the true circular shape by the introduction of flanges or small bosses, but they must be generally symmetrical about the axis to maintain balance. The inside surface of a true centrifugal casting is always cylindrical. The uniformity and density of centrifugal castings approach that of wrought material, with the added advantage that the mechanical properties are nearly equal in all directions. Since no gates and risers are used the yield or ratio of casting weight-to-weight of metal poured is high. A wide range of castings such as bearings, bushings and gears of all types for applications in general machine production, road building equipment, farm machinery and steel mill and marine applications are produced. The casting sizes usually range from 2” (50 mm) O.D. to 48” (115 mm) O.D.

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