Glastonbury Southern Gage
Erin, TN
Cylindrical Ring Gages
(Back to Contents)
Cylindrical Ring Gages have several uses unlike cylindrical plug gages. Plug gages check the
hole in the part. Cylindrical ring gages check the outside diameter of a part but also can be
used to set an instrument , air or electronic.
When used to check the part directly the rings are specified as GO or NOGO. When used to
set an instrument that checks the part they are referred to as Setting Rings. Setting rings are
specified as MASTER with bilateral tolerance, MIN with unilateral plus tolerance, MAX with
unilateral minus tolerance, MEAN with bilateral tolerance. Some but few manufacturers of air
and electronic gaging specify their MIN & MAX setting rings with bilateral tolerance. This is not
the normal practice but be safe and ask if you are not sure.
Cylindrical Ring Gage Designs
Cylindrical ring gages come in different designs based on size.
C:\Technical Information\2.7 Cyl Rings.doc
Glastonbury Southern Gage
Erin, TN
The designs for cylindrical ring gages are described in ASME standard B47.1. Rings below
1.510 are manufactured without a flange outer diameter. Like the example below.
Above 1.510 cylindrical rings are manufactured with a flanged diameter as pictured below.
The removal of excess material from the outside diameter lightens up the weight for easier use
by the operator.
C:\Technical Information\2.7 Cyl Rings.doc
Glastonbury Southern Gage
Erin, TN
Pictured below is a CARBIDE ring. The insert is solid carbide with the outside jacketed with
steel. A solid carbide ring would be heavy and accessible to damage on the outside do to
carbide being hard but brittle.
C:\Technical Information\2.7 Cyl Rings.doc