ANSI B27.7-1977 is an American National Standard covering three metric series of general-purpose tapered and reduced cross section retaining rings: Type 3AM1 basic external rings, Type 3BM1 basic internal rings, and Type 3CM1 external E-rings. The standard provides dimensional data for rings, shafts, housings, and grooves, along with material requirements, heat treatment, surface finishes, hardness testing procedures, permanent set limits, workmanship criteria, irregularity limitations, assembly guidance, recommended drawing formats, allowable loads, and performance information.
This reference is useful for engineers, designers, manufacturers, and quality professionals specifying or evaluating retaining rings in mechanical assemblies. All dimensions are provided in millimeters unless otherwise stated.
Application Scope: Metric design, specification, manufacturing, inspection, and installation of Type 3AM1 external retaining rings, Type 3BM1 internal retaining rings, and Type 3CM1 external E-rings used with shafts, housings, and circumferential grooves.
