Retaining Rings

Keep your shafts and pins in place with retaining rings
By W. Aiman Mueller Retaining rings are one of two types of fasteners that fix axial position. An external retaining, or snap ring, secures shafts or pins. An internal retaining ring fits into a bore. Most snap rings stay in place by "snapping" into a groove on the shaft.

A retaining ring manufacturer usually produces industrial retaining rings from spring or stainless steel, but specialty rings come in other materials, or have coatings, plating or finishes. Some retaining rings require retaining ring pliers or other special tools for application or removal. There are many types of retaining rings:

1. Circlip retaining rings are very common. On either side of a small gap, they have holed tabs or ears that accept pins on a special application tool.

2. Radial snap rings are for external assembly only.

3. Wire-formed snap rings, or Eaton style, rings have no ears.

4. Grooveless, or self-locking, retaining rings grasp a shaft that has no groove.

5. A spiral retaining ring has a coil shape, rather than a gap for widening.

6. Bowed retaining rings have a spring effect that compensates for play in a shaft.

7. An interlocking retaining ring has two halves that fit externally on the end of a shaft.

Get the part with the right specifications from an industrial retaining ring company

When buying external snap rings, consider your shaft diameter and the thickness of the groove. When it comes to internal retaining rings, you'll want to consider the housing diameter and depth. These rings also come in a range of maximum load ratings; the rating is known as ring shear.
Try:  Truarc Company, LLC has multiple styles of internal and external retaining rings. They carry many sizes up to 10 inches and even some up to 50 inches. They also carry assembly tools. Arcon is another good source for retaining rings. They include metric circlips in their stock.

Find very small or very large parts from snap ring distributors

Most snap ring distributors will cover the range of sizes, but some are better than others at hitting the extremes.
Try:  Small Parts, Inc. does well at the tiny end for snap rings, down to 1/16 inch. American Ring & Tool Co., however, is an all-around good place to find the right fit for your application. They clearly publish there product specifications with full detail, and they carry a wide range of sizes.

Buy hard-to-find retaining rings and specialty retaining ring distributors

Some part sources are industry-specific. Others carry a wider range of hard to find or less common retaining ring types.
Try:  Newport Corporation carries retaining rings that are best suited to labs and optical applications. Rotor Clip Company, Inc. is the place to go for the full range of shapes and styles, including spiral retaining rings and even wave springs.

• In cases when a retaining clip must conduct electricity, choose beryllium copper-composed rings.