Retaining rings
A 25 mm shaft takes its circlip in a groove Ø 23.9 0/−0.21 mm, 1.3 mm wide (H13) and 0.55 mm deep, at least 1.7 mm from the end of the shaft; the ring is 1.2 mm thick. Pick a shaft (DIN 471) or a bore (DIN 472) and its nominal diameter for the groove to cut, the ring that goes in it, the margin to leave and the loads the groove and the ring will take.
The ring is drawn seated in its groove, true to scale, with the part it holds pressing on it, so you can see which wall it bears on and why the margin matters.
DIN 471 · shaft Ø 25 mm
- Groove Ø d₂
- Groove width m (H13)
- Ring thickness s
- Edge margin n (min)
- Groove depth t
- Ring free Ø d₃
- Groove load capacity FN
- Ring load capacity FR
How it’s calculated
The groove depth is t = (d₁ − d₂) / 2. The ring bears on the groove’s wall nearer the end, so the margin n is the material that carries the thrust; FN is the groove’s capacity with n at least the table’s value in material with a 200 N/mm² yield point, FR the ring’s against a sharp-edged part. A dash is a value the sources do not agree on.
DIN 471 rings for shafts, normal series
| d₁ | s | d₃ (free) | d₂ (groove) | m (H13) | t | n min | FN kN | FR kN |
|---|---|---|---|---|---|---|---|---|
| 3 | 0.4 | 2.7 | 2.8 0/−0.04 | 0.5 | 0.1 | 0.3 | 0.15 | 0.47 |
| 4 | 0.4 | 3.7 | 3.8 | 0.5 | 0.1 | 0.3 | 0.2 | 0.5 |
| 5 | 0.6 | 4.7 | 4.8 | 0.7 | 0.1 | 0.3 | 0.26 | 1 |
| 6 | 0.7 | 5.6 | 5.7 | 0.8 | 0.15 | 0.5 | 0.46 | 1.45 |
| 7 | 0.8 | 6.5 | 6.7 0/−0.06 | 0.9 | 0.15 | 0.5 | 0.54 | 2.6 |
| 8 | 0.8 | 7.4 | 7.6 0/−0.06 | 0.9 | 0.2 | 0.6 | 0.81 | 3 |
| 9 | 1 | 8.4 | 8.6 | 1.1 | 0.2 | 0.6 | 0.92 | 3.5 |
| 10 | 1 | 9.3 | 9.6 | 1.1 | 0.2 | 0.6 | 1.01 | 4 |
| 11 | 1 | 10.2 | 10.5 0/−0.11 | 1.1 | 0.25 | 0.8 | 1.4 | 4.5 |
| 12 | 1 | 11 | 11.5 0/−0.11 | 1.1 | 0.25 | 0.8 | 1.53 | 5 |
| 13 | 1 | 11.9 | 12.4 0/−0.11 | 1.1 | 0.3 | 0.9 | 2 | 5.8 |
| 14 | 1 | 12.9 | 13.4 0/−0.11 | 1.1 | 0.3 | 0.9 | 2.15 | 6.35 |
| 15 | 1 | 13.8 | 14.3 0/−0.11 | 1.1 | 0.35 | 1.1 | 2.66 | 6.9 |
| 16 | 1 | 14.7 | 15.2 0/−0.11 | 1.1 | 0.4 | 1.2 | 3.26 | 7.4 |
| 17 | 1 | 15.7 | 16.2 0/−0.11 | 1.1 | 0.4 | 1.2 | 3.46 | 8 |
| 18 | 1.2 | 16.5 | 17 0/−0.11 | 1.3 | 0.5 | 1.5 | 4.58 | 17 |
| 19 | 1.2 | 17.5 | 18 0/−0.11 | 1.3 | 0.5 | 1.5 | — | 17 |
| 20 | 1.2 | 18.5 | 19 0/−0.13 | 1.3 | 0.5 | 1.5 | 5.06 | 17.1 |
| 21 | 1.2 | 19.5 | 20 0/−0.13 | 1.3 | 0.5 | 1.5 | 5.36 | 16.8 |
| 22 | 1.2 | 20.5 | 21 0/−0.13 | 1.3 | 0.5 | 1.5 | 5.65 | 16.9 |
| 24 | 1.2 | 22.2 | 22.9 0/−0.21 | 1.3 | 0.55 | 1.7 | 6.75 | 16.1 |
| 25 | 1.2 | 23.2 | 23.9 0/−0.21 | 1.3 | 0.55 | 1.7 | 7.05 | 16.2 |
| 26 | 1.2 | 24.2 | 24.9 0/−0.21 | 1.3 | 0.55 | 1.7 | 7.34 | 16.1 |
| 28 | 1.5 | 25.9 | 26.6 0/−0.21 | 1.6 | 0.7 | 2.1 | 10 | 32.1 |
| 29 | 1.5 | 26.9 | 27.6 0/−0.21 | 1.6 | 0.7 | 2.1 | 10.37 | 31.8 |
| 30 | 1.5 | 27.9 | 28.6 0/−0.21 | 1.6 | 0.7 | 2.1 | 10.73 | 32.1 |
| 32 | 1.5 | 29.6 | 30.3 0/−0.25 | 1.6 | 0.85 | 2.6 | 13.85 | 31.2 |
| 34 | 1.5 | 31.5 | 32.3 0/−0.25 | 1.6 | 0.85 | 2.6 | 14.72 | 31.3 |
| 35 | 1.5 | 32.2 | 33 0/−0.25 | 1.6 | 1 | 3 | 17.8 | 30.8 |
| 36 | 1.75 | 33.2 | 34 0/−0.25 | 1.85 | 1 | 3 | 18.33 | 49.4 |
| 38 | 1.75 | 35.2 | 36 0/−0.25 | 1.85 | 1 | 3 | 19.3 | 49.5 |
| 40 | 1.75 | 36.5 | 37.5 0/−0.25 | 1.85 | 1.25 | 3.8 | 25.3 | 51 |
| 42 | 1.75 | 38.5 | 39.5 0/−0.25 | 1.85 | 1.25 | 3.8 | 26.7 | 50 |
| 45 | 1.75 | 41.5 | 42.5 0/−0.25 | 1.85 | 1.25 | 3.8 | 28.6 | 49 |
| 48 | 1.75 | 44.5 | 45.5 0/−0.25 | 1.85 | 1.25 | 3.8 | 30.7 | 49.4 |
| 50 | 2 | 45.8 | 47 0/−0.25 | 2.15 | 1.5 | 4.5 | 38 | 73.3 |
| 52 | 2 | 47.8 | 49 0/−0.25 | 2.15 | 1.5 | 4.5 | 39.7 | 73.1 |
| 55 | 2 | 50.8 | 52 0/−0.3 | 2.15 | 1.5 | 4.5 | 42 | 71.4 |
| 56 | 2 | 51.8 | 53 0/−0.3 | 2.15 | 1.5 | 4.5 | 42.8 | 70.8 |
| 58 | 2 | 53.8 | 55 0/−0.3 | 2.15 | 1.5 | 4.5 | 44.3 | 71.1 |
| 60 | 2 | 55.8 | 57 0/−0.3 | 2.15 | 1.5 | 4.5 | 46 | 69.2 |
| 62 | 2 | 57.8 | 59 0/−0.3 | 2.15 | 1.5 | 4.5 | 47.5 | 69.3 |
| 63 | 2 | 58.8 | 60 0/−0.3 | 2.15 | 1.5 | 4.5 | 48.3 | 70.2 |
| 65 | 2.5 | 60.8 | 62 0/−0.3 | 2.65 | 1.5 | 4.5 | 49.8 | 135.6 |
| 68 | 2.5 | 63.5 | 65 0/−0.3 | 2.65 | 1.5 | 4.5 | 52.2 | 135.9 |
| 70 | 2.5 | 65.5 | 67 0/−0.3 | 2.65 | 1.5 | 4.5 | 53.8 | 134.2 |
| 72 | 2.5 | 67.5 | 69 0/−0.3 | 2.65 | 1.5 | 4.5 | 55.3 | 131.8 |
| 75 | 2.5 | 70.5 | 72 0/−0.3 | 2.65 | 1.5 | 4.5 | 57.6 | 130 |
| 78 | 2.5 | 73.5 | 75 0/−0.3 | 2.65 | 1.5 | 4.5 | 60 | 131.3 |
| 80 | 2.5 | 74.5 | 76.5 0/−0.3 | 2.65 | 1.75 | 5.3 | 71.6 | 128.4 |
| 82 | 2.5 | 76.5 | 78.5 0/−0.3 | 2.65 | 1.75 | 5.3 | 73.5 | 128 |
| 85 | 3 | 79.5 | 81.5 | 3.15 | 1.75 | 5.3 | 76.2 | 215.4 |
| 88 | 3 | 82.5 | 84.5 | 3.15 | 1.75 | 5.3 | 79 | 221.8 |
| 90 | 3 | 84.5 | 86.5 | 3.15 | 1.75 | 5.3 | 80.8 | 217.2 |
| 95 | 3 | 89.5 | 91.5 | 3.15 | 1.75 | 5.3 | 85.5 | 212.2 |
| 100 | 3 | 94.5 | 96.5 | 3.15 | 1.75 | 5.3 | 90 | 206.4 |
| 105 | 4 | 98 | 101 0/−0.54 | 4.15 | 2 | 6 | 107.6 | 471.8 |
| 110 | 4 | 103 | 106 0/−0.54 | 4.15 | 2 | 6 | 113 | 457 |
| 115 | 4 | 108 | 111 0/−0.54 | 4.15 | 2 | 6 | 118.2 | 438.6 |
| 120 | 4 | 113 | 116 0/−0.54 | 4.15 | 2 | 6 | 123.5 | — |
| 125 | 4 | 118 | 121 0/−0.63 | 4.15 | 2 | 6 | 128.7 | 411.5 |
| 130 | 4 | 123 | 126 0/−0.63 | 4.15 | 2 | 6 | 134 | — |
| 135 | 4 | 128 | 131 0/−0.63 | 4.15 | 2 | 6 | 139.2 | 389.5 |
| 140 | 4 | 133 | 136 0/−0.63 | 4.15 | 2 | 6 | 144.5 | 376.5 |
| 145 | 4 | 138 | 141 0/−0.63 | 4.15 | 2 | 6 | 149.6 | 367 |
| 150 | 4 | 142 | 145 0/−0.63 | 4.15 | 2.5 | 7.5 | 193 | 357.5 |
| 155 | 4 | 146 | 150 0/−0.63 | 4.15 | 2.5 | 7.5 | 199.6 | 352.9 |
| 160 | 4 | 151 | 155 0/−0.63 | 4.15 | 2.5 | 7.5 | 206.1 | 349.2 |
| 165 | 4 | 155.5 | 160 0/−0.63 | 4.15 | 2.5 | 7.5 | 212.5 | 345.3 |
| 170 | 4 | 160.5 | 165 0/−0.63 | 4.15 | 2.5 | 7.5 | 219.1 | 349.2 |
| 175 | 4 | 165.5 | 170 0/−0.63 | 4.15 | 2.5 | 7.5 | 225.5 | 340.1 |
| 180 | 4 | — | 175 0/−0.63 | 4.15 | 2.5 | 7.5 | 232.2 | 345.3 |
| 185 | 4 | 175.5 | 180 0/−0.63 | 4.15 | 2.5 | 7.5 | 238.6 | 336.7 |
| 190 | 4 | 180.5 | 185 0/−0.72 | 4.15 | 2.5 | 7.5 | 245.1 | 333.8 |
| 195 | 4 | 185.5 | 190 0/−0.72 | 4.15 | 2.5 | 7.5 | 251.8 | 325.4 |
| 200 | 4 | 190.5 | 195 0/−0.72 | 4.15 | 2.5 | 7.5 | 258.3 | 319.2 |
Why does the edge margin matter?
A retaining ring takes its thrust through the groove’s wall nearer the end of the shaft or bore, so the material between that wall and the end, the margin n, is what shears if the load is too high. The groove’s load capacity in the tables assumes at least that margin in material with a 200 N/mm² yield point; a chamfer at the end, or a softer material, leaves less. The ring’s own capacity assumes the part it holds has a sharp edge against it: a part with a chamfer or a radius levers the ring out of its groove at a lower load.