CONCENTRICITY OF CASTINGS

Concentricity is the position of two or more cylindrical surfaces (A and B) in respect to a common axis. Concentricity tolerance is one half the difference in the diameters of a cylindrical tolerance zone about which axis the feature so toleranced must lie.

Concentricity of cylindrical surfaces is affected by the design of the casting. Factors involved include the size, wall thickness, shape and complexity of the casting.

This standard applies to castings having maximum rigidity and uniformity of shape and wall thickness. Under these conditions castings may be slightly out-of-round but this ovality is included in the concentricity tolerances. Castings containing inserts are not covered by this standard. Concentricity tolerances will only apply when specified on the drawing.