Circlip Size Guide: How to Select the Correct Size

Choosing the right circlip is about more than matching a diameter. The shaft or bore size, groove dimensions, circlip thickness, material and applicable standard all influence whether the circlip will fit correctly and provide reliable retention.

Whether you need an external, internal or E-type circlip, understanding how sizing works can help you avoid incorrect selection and installation problems.

Quick Guide to Circlip Sizing

The easiest way to identify the correct size is to first determine where the circlip will be installed. An external circlip fits into a groove on a shaft, while an internal circlip fits into a groove inside a bore. Their nominal sizes are based on the shaft and bore diameter respectively.

Circlip Size Chart

Circlip Type	Standard	Nominal Size Based On	Typical Application
External Circlip	DIN 471	Shaft Diameter	Shafts
Internal Circlip	DIN 472	Bore Diameter	Housings
E-Type Circlip	DIN 6799	Shaft Diameter	Compact Assemblies

Shiv Sagar Industries offers internal, external and E-type circlips as part of its circlip range.

External vs Internal Circlip: What’s the Difference?

An external circlip is installed around a shaft and sits in an external groove. DIN 471 is the commonly used standard for this type.

An internal circlip is installed inside a bore or housing and sits in an internal groove. DIN 472 is commonly used for these applications.

The two types are not interchangeable because they work in opposite directions during installation and retention.

How to Select the Correct Circlip Size

1. Identify the Type

Determine whether the groove is on a shaft, inside a bore, or designed for an E-type circlip.

2. Measure the Shaft or Bore

For an external circlip, measure the shaft diameter. For an internal circlip, measure the bore diameter. These dimensions determine the nominal size.

3. Verify the Groove

Check the groove diameter, width and depth to ensure they correspond with the selected circlip standard.

4. Check Thickness and Material

The circlip thickness should suit the groove, while the material should be appropriate for the operating environment and application.

5. Confirm the Standard

Always verify the applicable DIN, IS or customer specification before placing an order.

Common Circlip Selection Mistakes

• Measuring the loose circlip instead of the shaft or bore
• Confusing internal and external circlips
• Ignoring groove dimensions
• Selecting only by diameter without checking the standard
• Overlooking material and application requirements

FAQs About Circlip Size

How do I measure a circlip size?

Measure the nominal shaft diameter for an external circlip or bore diameter for an internal circlip—not simply the free diameter of the circlip.

What is the difference between DIN 471 and DIN 472?

DIN 471 applies to external circlips for shafts, while DIN 472 applies to internal circlips for bores.

Can I choose a circlip based only on diameter?

No. Groove width, groove depth, thickness, series, material, and applicable standard should also be verified.

What material is best for circlips?

Spring steel is suitable for many industrial applications, while stainless steel is preferred where greater corrosion resistance is required.

Need Help Selecting the Right Circlip?

Not sure which specification you need? Share your shaft or bore diameter, groove dimensions, material requirement, quantity and applicable drawing or standard with Shiv Sagar Industries. The team can help identify the appropriate circlip specification for your application. Shiv Sagar Industries also manufactures custom circlips according to drawings and specifications.

Explore the range of precision-engineered internal, external and E-type circlips from Shiv Sagar Industries.