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Shim Ring Dimensions (DIN 988, 3 to 170 mm)
Guide · Updated October 28, 2026
DIN 988 covers shim rings and support rings for shafts, 3 to 170 mm bore. Diameters and limits agree between the fasteners.eu DIN 988 table and a published DIN 988 sheet (Depinspro); nominal size pairs to 50 x 63 also match the Spinelli DIN 988 sheet, and the thickness series matches fasteners.eu, Spinelli and the Depinspro limits. Conflicting cells are shown as a dash. Check your supplier for critical work.
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Step by step
- Find the shaft size: d1 is the nominal inside diameter; pick the row for your shaft.
- Pick the OD: Some shaft sizes have two ODs (e.g. 22 x 30 and 22 x 32); choose the one that fits the housing or circlip.
- Check the limits: d1 is D12 and d2 is d12; read min and max.
- Choose the thickness: Stack standard thicknesses (0.1 to 2 mm) to make up the gap.
- Order it: Designate as Shim ring DIN 988 - 20 x 28 x 0.5.
DIN 988 shim ring dimensions (mm)
Columns: inside diameter d1 nominal, min and max (D12); outside diameter d2 nominal, min and max (d12). Thickness series: 0.1, 0.15, 0.2, 0.3, 0.5, 1.0, 1.1 ... 2.0 mm.
- d1 | d1 min | d1 max | d2 | d2 min | d2 max
- 3 | 3.02 | 3.12 | 6 | 5.85 | 5.97
- 4 | 4.03 | 4.15 | 8 | 7.81 | 7.96
- 5 | 5.03 | 5.15 | 10 | 9.81 | 9.96
- 6 | 6.03 | 6.15 | 12 | 11.77 | 11.95
- 7 | 7.04 | — | 13 | 12.77 | 12.95
- 8 | 8.04 | 8.19 | 14 | 13.77 | 13.95
- 9 | 9.04 | 9.19 | 15 | 14.77 | 14.95
- 10 | 10.04 | 10.19 | 16 | 15.77 | 15.95
- 11 | 11.05 | 11.23 | 17 | 16.77 | 16.95
- 12 | 12.05 | 12.23 | 18 | 17.77 | 17.95
- 13 | 13.05 | 13.23 | 19 | 18.725 | 18.935
- 14 | 14.05 | 14.23 | 20 | 19.725 | 19.935
- 15 | 15.05 | 15.23 | 21 | 20.725 | 20.935
- 16 | 16.05 | 16.23 | 22 | 21.725 | 21.935
- 17 | 17.05 | 17.23 | 24 | 23.725 | 23.935
- 18 | 18.05 | 18.23 | 25 | 24.725 | 24.935
- 19 | 19.065 | 19.275 | 26 | 25.725 | 25.935
- 20 | 20.065 | 20.275 | 28 | 27.725 | 27.935
- 22 | 22.065 | 22.275 | 30 | 29.725 | 29.935
- 22 | 22.065 | 22.275 | 32 | 31.67 | 31.92
- 25 | 25.065 | 25.275 | 35 | 34.67 | 34.92
- 25 | 25.065 | 25.275 | 36 | 35.67 | —
- 26 | 26.065 | 26.275 | 37 | 36.67 | 36.92
- 28 | 28.065 | 28.275 | 40 | 39.67 | 39.92
- 30 | 30.065 | — | 42 | 41.67 | 41.92
- 32 | 32.08 | 32.33 | 45 | 44.67 | 44.92
- 35 | 35.08 | 35.33 | 45 | 44.67 | 44.92
- 36 | 36.08 | 36.33 | 45 | 44.67 | 44.92
- 37 | 37.08 | 37.33 | 47 | 46.67 | 46.92
- 40 | 40.08 | 40.33 | 50 | 49.67 | 49.92
- 42 | 42.08 | 42.33 | 52 | 51.6 | 51.9
- 45 | 45.08 | 45.33 | 55 | 54.6 | 54.9
- 45 | 45.08 | 45.33 | 56 | 55.6 | 55.9
- 48 | 48.08 | 48.33 | 60 | 59.6 | 59.9
- 50 | 50.08 | 50.33 | 62 | 61.6 | 61.9
- 50 | 50.08 | 50.33 | 63 | 62.6 | 62.9
- 52 | 52.1 | 52.4 | 65 | 64.6 | 64.9
- 55 | 55.1 | 55.4 | 68 | 67.6 | 67.9
- 56 | 56.1 | 56.4 | 70 | 69.6 | 69.9
- 56 | 56.1 | 56.4 | 72 | 71.6 | 71.9
- 60 | 60.1 | 60.4 | 75 | 74.6 | 74.9
- 63 | 63.1 | 63.4 | 80 | 79.6 | 79.9
- 65 | 65.1 | 65.4 | 85 | 84.53 | 84.88
- 70 | 70.1 | 70.4 | 90 | — | 89.88
- 75 | 75.1 | 75.4 | 95 | 94.53 | 94.88
- 80 | 80.1 | 80.4 | 100 | 99.53 | 99.88
- 85 | 85.12 | 85.47 | 105 | 104.53 | 104.88
- 90 | 90.12 | 90.47 | 110 | 109.53 | 109.88
- 95 | 95.12 | 95.47 | 115 | 114.53 | 114.88
- 100 | 100.12 | 100.47 | 120 | 119.53 | 119.88
- 100 | 100.12 | 100.47 | 125 | — | —
- 105 | 105.12 | 105.47 | 130 | — | —
- 110 | 110.12 | 110.47 | 140 | — | —
- 120 | 120.12 | 120.47 | 150 | — | —
- 130 | 130.145 | 130.545 | 160 | — | —
- 140 | 140.145 | 140.545 | 170 | — | —
- 150 | 150.145 | 150.545 | 180 | — | —
- 160 | 160.145 | 160.545 | 190 | 189.37 | 189.83
- 170 | 170.145 | 170.545 | 200 | 199.37 | —
Worked example: 0.65 mm of end play on a 20 mm shaft
Use 20 x 28 rings (d1 20.065 to 20.275, d2 27.725 to 27.935): stack 0.5 + 0.15 mm, then measure the stack and the remaining play.
Common problems
- Ring rubs the housing: pick the smaller OD option or check d2 max.
- Stack too thick: thickness min is below nominal; measure the stack.
- Ring rides on the circlip groove edge: check d1 against the shaft.
FAQ
What is DIN 988?
Thin precision shim rings and thicker support rings used to take up axial play on shafts, often next to a DIN 471 or DIN 472 circlip.
Which thicknesses are standard?
0.1, 0.15, 0.2, 0.3, 0.5, then 1 to 2 mm in 0.1 mm steps, with max = nominal and min = 0.07, 0.12, 0.16, 0.25, 0.45, then nominal minus 0.05. Not every thickness is listed for every size.
Why are some limits blank?
Sources disagree: size 7 d1 max (7.19 vs 7.09), size 30 d1 max (30.275 vs 30.725), 25 x 36 d2 max (35.93 vs 35.92), 70 x 90 d2 min (89.53 vs 59.53), and 100 x 125 to 150 x 180 d2 limits (e.g. 124.455 vs 124.46).
Is 0.25 mm standard?
It appears in some sources (Depinspro sheet, Paal catalog) but not in fasteners.eu or Spinelli, so it is not listed.
What was skipped?
Weights, which thickness each size is listed in, flatness and the cells noted above.
Related guides and calculators
- Spherical washers (DIN 6319)
- Metric clevis pins (ISO 2341 / DIN 1444)
- DIN 471 external circlip size chart
- DIN 472 internal circlip size chart
- Clevis pin washer dimensions (ISO 8738 / DIN 1440)
- Thick washer dimensions (DIN 7349)
- Flat washer size chart (SAE, USS, metric)
- All free machinist calculators
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