d8 tolerance (shaft, IT8)
Shaft tolerance class d8 per ISO 286-1:2010: fundamental deviation es −20 … −230, grade IT8 (14 µm at ≤ 3 mm to 97 µm at 400–500 mm). For an exact size, open the calculator with d8 selected.
- Type
- Shaft
- Grade
- IT8
- Tolerance
- 14 … 97 µm
- Fund. deviation
- es −20 … −230 µm
d8 limits by size range
| Size (mm) | Upper (µm) | Lower (µm) | Ø max (mm) | Ø min (mm) | Upper (mm) | Lower (mm) | Dev. (in) |
|---|---|---|---|---|---|---|---|
| ≤ 3 | −20 | −34 | 2.980 | 2.966 | −0.020 | −0.034 | −0.00079 / −0.00134 |
| 3 – 6 | −30 | −48 | 5.970 | 5.952 | −0.030 | −0.048 | −0.00118 / −0.00189 |
| 6 – 10 | −40 | −62 | 9.960 | 9.938 | −0.040 | −0.062 | −0.00157 / −0.00244 |
| 10 – 14 | −50 | −77 | 13.950 | 13.923 | −0.050 | −0.077 | −0.00197 / −0.00303 |
| 14 – 18 | −50 | −77 | 17.950 | 17.923 | −0.050 | −0.077 | −0.00197 / −0.00303 |
| 18 – 24 | −65 | −98 | 23.935 | 23.902 | −0.065 | −0.098 | −0.00256 / −0.00386 |
| 24 – 30 | −65 | −98 | 29.935 | 29.902 | −0.065 | −0.098 | −0.00256 / −0.00386 |
| 30 – 40 | −80 | −119 | 39.920 | 39.881 | −0.080 | −0.119 | −0.00315 / −0.00469 |
| 40 – 50 | −80 | −119 | 49.920 | 49.881 | −0.080 | −0.119 | −0.00315 / −0.00469 |
| 50 – 65 | −100 | −146 | 64.900 | 64.854 | −0.100 | −0.146 | −0.00394 / −0.00575 |
| 65 – 80 | −100 | −146 | 79.900 | 79.854 | −0.100 | −0.146 | −0.00394 / −0.00575 |
| 80 – 100 | −120 | −174 | 99.880 | 99.826 | −0.120 | −0.174 | −0.00472 / −0.00685 |
| 100 – 120 | −120 | −174 | 119.880 | 119.826 | −0.120 | −0.174 | −0.00472 / −0.00685 |
| 120 – 140 | −145 | −208 | 139.855 | 139.792 | −0.145 | −0.208 | −0.00571 / −0.00819 |
| 140 – 160 | −145 | −208 | 159.855 | 159.792 | −0.145 | −0.208 | −0.00571 / −0.00819 |
| 160 – 180 | −145 | −208 | 179.855 | 179.792 | −0.145 | −0.208 | −0.00571 / −0.00819 |
| 180 – 200 | −170 | −242 | 199.830 | 199.758 | −0.170 | −0.242 | −0.00669 / −0.00953 |
| 200 – 225 | −170 | −242 | 224.830 | 224.758 | −0.170 | −0.242 | −0.00669 / −0.00953 |
| 225 – 250 | −170 | −242 | 249.830 | 249.758 | −0.170 | −0.242 | −0.00669 / −0.00953 |
| 250 – 280 | −190 | −271 | 279.810 | 279.729 | −0.190 | −0.271 | −0.00748 / −0.01067 |
| 280 – 315 | −190 | −271 | 314.810 | 314.729 | −0.190 | −0.271 | −0.00748 / −0.01067 |
| 315 – 355 | −210 | −299 | 354.790 | 354.701 | −0.210 | −0.299 | −0.00827 / −0.01177 |
| 355 – 400 | −210 | −299 | 399.790 | 399.701 | −0.210 | −0.299 | −0.00827 / −0.01177 |
| 400 – 450 | −230 | −327 | 449.770 | 449.673 | −0.230 | −0.327 | −0.00906 / −0.01287 |
| 450 – 500 | −230 | −327 | 499.770 | 499.673 | −0.230 | −0.327 | −0.00906 / −0.01287 |
Deviations at the upper end of each range (Ø columns use that size); use the calculator for the exact size. — : not defined by ISO 286 for that size. Upper/Lower (mm) and inch columns are shown on wider screens.
About d8
d8 denotes a shaft tolerance zone with running clearance deviation in the ISO 286 system. It is used in H7/d8 (Free-running clearance for shafts in simple plain bearings subject to dirt, misalignment or thermal growth: material-handling rollers, low-speed gearbox shafts.).
At Ø25 mm d8 is −0.065 / −0.098 mm, i.e. 24.902 to 24.935 mm.
How the limits are calculated
d8 uses grade IT8 (a standard tolerance of 33 µm at 18–30 mm). Fundamental deviation: es is tabulated directly by ISO 286-1 Table 2; ei = es − IT8. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.