Cylindrical ring gages have a number of inspection purposes. They are used as Go/No-Go gages to inspect the outside diameter of a shaft or rod. They are masters for dial bore gages, internal micrometers and coordinate measuring machines (CMMs). They work well in applications where functional maximum material condition inspection of a shaft or other outside diameter is required.
In the United States, cylindrical plain ring gages are fixed limit gages manufactured per ASME B89.1.6. This standard defines the dimensional and geometric tolerances for the cylindrical ring gages. See the Diameter Tolerance chart (Fig. 1).