Retaining Rings & Circlips
Washers & Retaining Rings · 9 specs
Direct Answer
Retaining rings (circlips) provide removable shoulder stops in machined shaft and bore grooves, standardized under DIN 471 (External shaft circlips), DIN 472 (Internal bore circlips), and DIN 6799 (Radial E-clips).
Source: DIN 471 (Shaft) / DIN 472 (Bore) / DIN 6799 (E-Clip) / ASME B18.27 · Last reviewed Aug 28, 2026
Specs
| Governing Standards | DIN 471 (External) / DIN 472 (Internal) / DIN 6799 (E-Clip) |
| DIN 471 10mm External Circlip | Shaft Dia: 10 mm | Groove Dia: 9.6 mm | Groove Width: 1.1 mm | Ring Thickness: 1.0 mm |
| DIN 471 15mm External Circlip | Shaft Dia: 15 mm | Groove Dia: 14.3 mm | Groove Width: 1.1 mm | Ring Thickness: 1.0 mm |
| DIN 471 20mm External Circlip | Shaft Dia: 20 mm | Groove Dia: 19.0 mm | Groove Width: 1.3 mm | Ring Thickness: 1.2 mm |
| DIN 471 25mm External Circlip | Shaft Dia: 25 mm | Groove Dia: 23.9 mm | Groove Width: 1.3 mm | Ring Thickness: 1.2 mm |
| DIN 472 20mm Internal Circlip | Bore Dia: 20 mm | Groove Dia: 21.0 mm | Groove Width: 1.1 mm | Ring Thickness: 1.0 mm |
| DIN 472 25mm Internal Circlip | Bore Dia: 25 mm | Groove Dia: 26.2 mm | Groove Width: 1.3 mm | Ring Thickness: 1.2 mm |
| DIN 6799 E-Clip (Radial Installation) | Installed radially with push tool without requiring axial shaft access |
| Standard Material | Spring Steel (C67S / C75S / 50CrV4) hardened to 44–53 HRC, Stainless AISI 301/304 |
DIN 471 (Shaft) & DIN 472 (Bore) Circlip Groove Dimensions
| Nominal Shaft / Bore Size | Type | Free Unstressed Ring Dia (d_3) | Machined Groove Dia (d_2) | Groove Width (m) | Ring Thickness (s) | Max Thrust Load (F_r) |
|---|---|---|---|---|---|---|
| 8 mm Shaft | DIN 471 External | 7.4 mm | 7.6 mm (-0.06) | 0.90 mm | 0.80 mm | 2.55 kN |
| 10 mm Shaft | DIN 471 External | 9.3 mm | 9.6 mm (-0.09) | 1.10 mm | 1.00 mm | 3.80 kN |
| 15 mm Shaft | DIN 471 External | 13.8 mm | 14.3 mm (-0.11) | 1.10 mm | 1.00 mm | 6.80 kN |
| 20 mm Shaft | DIN 471 External | 18.5 mm | 19.0 mm (-0.13) | 1.30 mm | 1.20 mm | 17.1 kN |
| 25 mm Shaft | DIN 471 External | 23.2 mm | 23.9 mm (-0.21) | 1.30 mm | 1.20 mm | 24.8 kN |
| 20 mm Bore | DIN 472 Internal | 21.5 mm | 21.0 mm (+0.13) | 1.10 mm | 1.00 mm | 11.2 kN |
| 25 mm Bore | DIN 472 Internal | 26.9 mm | 26.2 mm (+0.21) | 1.30 mm | 1.20 mm | 18.0 kN |
| 30 mm Bore | DIN 472 Internal | 32.1 mm | 31.4 mm (+0.25) | 1.60 mm | 1.50 mm | 28.6 kN |
Orientation & Groove Edge Radii Best Practices
Because retaining rings are stamped from flat spring sheet, one face features a rounded die-rolled edge while the opposite face has a sharp, square shearing edge:
- Direction of Thrust Rule: Always install the circlip with its sharp square edge facing the thrust load (toward the bearing or gear). The rounded edge should face the bottom of the groove. Reversing this orientation reduces axial load capacity by over 40%.
- Groove Bottom Radius: Grooves must be machined with a small corner radius (R ≤ 0.1 × s) to prevent stress riser fatigue cracks while allowing the sharp ring edge to seat firmly against the groove wall.