How is cylindricity inspected?

How is cylindricity inspected?

• A. By considering both circularity and straightness along the axis of a cylindrical surface to keep the surface within a cylindrical envelope.
• B. By measuring only the circularity of the cross-section.
• C. By checking concentricity with a datum axis.
• D. By applying a true position tolerance to the centerline.

Answer: (A)

Cylindricity controls how far a cylindrical surface can deviate from an ideal cylinder by demanding both the circularity of each cross-section and the straightness of the surface along its axis. When inspecting, you verify that every cross-section is as circular as the tolerance allows and that the axis of the surface remains straight along the length. Together these checks ensure the entire surface lies within a cylindrical envelope coaxial with the datum axis, if one is specified. Circularity alone misses how the surface runs along the length, so it can’t guarantee straightness of the axis. Concentricity is about how the surface distributes around a datum axis and doesn’t address the actual form of the surface along its length. And true position on the centerline relates to location rather than the inherent form of the cylindrical surface.

Cylindricity controls how far a cylindrical surface can deviate from an ideal cylinder by demanding both the circularity of each cross-section and the straightness of the surface along its axis. When inspecting, you verify that every cross-section is as circular as the tolerance allows and that the axis of the surface remains straight along the length. Together these checks ensure the entire surface lies within a cylindrical envelope coaxial with the datum axis, if one is specified. Circularity alone misses how the surface runs along the length, so it can’t guarantee straightness of the axis. Concentricity is about how the surface distributes around a datum axis and doesn’t address the actual form of the surface along its length. And true position on the centerline relates to location rather than the inherent form of the cylindrical surface.