Key Points
Circularity is a condition of a surface where:
- for a feature other than a sphere, all points of the surface intersected by any plane perpendicular to an axis are equidistant to that axis.
- for a sphere, all points of the surface intersected by any plane passing through a common center are equidistant from that center.
Circularity is a 2D tolerance. It controls circular elements, not longitudinal elements. Each circular element of the surface in a plane perpendicular to the axis must lie between two concentric circles, one having a radius 0.03 larger than the other. In addition, the feature must be within the limits of size, including perfect from at MMC.
Example Drawing
How to Read It
Circularity allows the shape of the feature to be waisted, barrelled, bowed, or tapered within the size tolerance. Circularity controls only the circular elements of the feature
