Safety Ring DIN 472

Circlips to DIN 472 for Bores

Circlips to DIN 472 are used to retain components axially inside a bore or housing. They are installed in a suitable internal groove, where they form a positive mechanical stop. This allows rolling bearings, bushes, seals, sleeves or covers to be secured against axial movement.

For installation, the ring is compressed using suitable circlip pliers, inserted into the bore and released into the intended groove. It must then be seated completely around its entire circumference.

DIN 472 specifies requirements for circlips for bores and the corresponding grooves. Use the product table above to select a suitable version by bore diameter, groove dimensions, free ring diameter, material thickness, mounting-hole diameter, axial load and material.

Meaning of the Specifications in the Product Table

How to Select the Right Circlip

Proceed in the following order:

1. Determine the bore diameter: The nominal size is based on the bore or housing diameter Db.

2. Check the groove dimensions: Groove diameter Dn and groove width b must match the selected ring. An existing groove should be measured carefully.

3. Check the installation space: Sufficient space is required for the circlip pliers and for inserting the compressed ring axially.

4. Assess the axial load: Consider static, alternating and impact loads. The weakest part of the complete retaining arrangement determines the actual load capacity.

5. Check the contact surface: The retained component must provide a sufficiently large contact area against the circlip. Large chamfers or radii may reduce the effective supporting surface.

6. Consider the operating environment: Humidity, temperature, cleaning agents and other media may create additional requirements for the material or surface finish.

For high axial loads, impact loading or safety-relevant applications, the groove strength, housing material and actual contact geometry must also be assessed.

Difference Between DIN 472 and DIN 471

Circlips to DIN 472 are installed internally inside a bore. The ring is compressed during installation and then released into the internal groove.

Circlips to DIN 471, by comparison, are installed externally on a shaft and are expanded during installation.

The two designs are not interchangeable. To secure a bearing, gear or other component on a shaft, use a circlip for shafts to DIN 471.

Correct Design of the Groove and Adjacent Component

The groove must be accurately machined, clean and free from burrs. Its dimensions affect both the secure seating of the ring and the remaining axial play.

The distance between the groove and the open end of the bore must also be sufficient. The remaining housing shoulder must withstand the applied axial force. If the edge distance is too small, the shoulder may break away even though the circlip itself has sufficient load capacity.

The retained component should contact the ring with a flat end face. Large chamfers or radii reduce the effective contact surface. A sufficiently rigid support washer may be used to distribute the load more evenly.

Installation and Removal

Use internal circlip pliers whose tips match mounting-hole diameter R and the ring size. Compress the ring only as far as necessary for insertion. Excessive compression may cause permanent deformation.

Before installation, the circlip and groove must be clean and free from damage. After insertion, check that the ring is seated completely around its entire circumference. A circlip that is only partially engaged must not be loaded.

For removal, compress the ring using suitable internal circlip pliers. Circlips that are damaged, corroded or permanently deformed should not be reused.

Eye protection is recommended during installation and removal because a tensioned ring may spring away from the pliers or groove if handled incorrectly.

Typical Applications

Circlips to DIN 472 are commonly used in:

• bearing and gearbox housings,

• electric motors and pumps,

• hydraulic and pneumatic components,

• rollers, hubs and couplings,

• vehicle and machine assemblies,

• fixtures and technical equipment.

They provide a compact, removable and economical method of axial retention inside a bore without requiring an additional cover or bolted retaining plate.

Frequently Asked Questions About Circlips to DIN 472

How is the correct size determined?

The nominal size is based on bore diameter Db. Groove diameter Dn and groove width b must also match the selected ring.

Can the ring be installed without a groove?

No. A circlip to DIN 472 requires a correctly dimensioned internal groove in which it can engage positively.

Does Fr represent the load capacity of the complete assembly?

No. Fr is the stated axial load value for the circlip. The groove, housing material, edge distance and contact surface may reduce the permissible load of the complete assembly.

Can a circlip be reused?

Only if it has not been permanently deformed, damaged or affected by corrosion. A new ring should be used for safety-relevant applications.

Which tool is required?

Internal circlip pliers are required. The plier tips must fit mounting-hole diameter R.

Further information can be found in our FAQ on circlips to DIN 471 and DIN 472.