e8 tolerance (shaft, IT8)
Shaft tolerance class e8 per ISO 286-1:2010: fundamental deviation es −14 … −135, grade IT8 (14 µm at ≤ 3 mm to 97 µm at 400–500 mm). For an exact size, open the calculator with e8 selected.
- Type
- Shaft
- Grade
- IT8
- Tolerance
- 14 … 97 µm
- Fund. deviation
- es −14 … −135 µm
e8 limits by size range
| Size (mm) | Upper (µm) | Lower (µm) | Ø max (mm) | Ø min (mm) | Upper (mm) | Lower (mm) | Dev. (in) |
|---|---|---|---|---|---|---|---|
| ≤ 3 | −14 | −28 | 2.986 | 2.972 | −0.014 | −0.028 | −0.00055 / −0.00110 |
| 3 – 6 | −20 | −38 | 5.980 | 5.962 | −0.020 | −0.038 | −0.00079 / −0.00150 |
| 6 – 10 | −25 | −47 | 9.975 | 9.953 | −0.025 | −0.047 | −0.00098 / −0.00185 |
| 10 – 14 | −32 | −59 | 13.968 | 13.941 | −0.032 | −0.059 | −0.00126 / −0.00232 |
| 14 – 18 | −32 | −59 | 17.968 | 17.941 | −0.032 | −0.059 | −0.00126 / −0.00232 |
| 18 – 24 | −40 | −73 | 23.960 | 23.927 | −0.040 | −0.073 | −0.00157 / −0.00287 |
| 24 – 30 | −40 | −73 | 29.960 | 29.927 | −0.040 | −0.073 | −0.00157 / −0.00287 |
| 30 – 40 | −50 | −89 | 39.950 | 39.911 | −0.050 | −0.089 | −0.00197 / −0.00350 |
| 40 – 50 | −50 | −89 | 49.950 | 49.911 | −0.050 | −0.089 | −0.00197 / −0.00350 |
| 50 – 65 | −60 | −106 | 64.940 | 64.894 | −0.060 | −0.106 | −0.00236 / −0.00417 |
| 65 – 80 | −60 | −106 | 79.940 | 79.894 | −0.060 | −0.106 | −0.00236 / −0.00417 |
| 80 – 100 | −72 | −126 | 99.928 | 99.874 | −0.072 | −0.126 | −0.00283 / −0.00496 |
| 100 – 120 | −72 | −126 | 119.928 | 119.874 | −0.072 | −0.126 | −0.00283 / −0.00496 |
| 120 – 140 | −85 | −148 | 139.915 | 139.852 | −0.085 | −0.148 | −0.00335 / −0.00583 |
| 140 – 160 | −85 | −148 | 159.915 | 159.852 | −0.085 | −0.148 | −0.00335 / −0.00583 |
| 160 – 180 | −85 | −148 | 179.915 | 179.852 | −0.085 | −0.148 | −0.00335 / −0.00583 |
| 180 – 200 | −100 | −172 | 199.900 | 199.828 | −0.100 | −0.172 | −0.00394 / −0.00677 |
| 200 – 225 | −100 | −172 | 224.900 | 224.828 | −0.100 | −0.172 | −0.00394 / −0.00677 |
| 225 – 250 | −100 | −172 | 249.900 | 249.828 | −0.100 | −0.172 | −0.00394 / −0.00677 |
| 250 – 280 | −110 | −191 | 279.890 | 279.809 | −0.110 | −0.191 | −0.00433 / −0.00752 |
| 280 – 315 | −110 | −191 | 314.890 | 314.809 | −0.110 | −0.191 | −0.00433 / −0.00752 |
| 315 – 355 | −125 | −214 | 354.875 | 354.786 | −0.125 | −0.214 | −0.00492 / −0.00843 |
| 355 – 400 | −125 | −214 | 399.875 | 399.786 | −0.125 | −0.214 | −0.00492 / −0.00843 |
| 400 – 450 | −135 | −232 | 449.865 | 449.768 | −0.135 | −0.232 | −0.00531 / −0.00913 |
| 450 – 500 | −135 | −232 | 499.865 | 499.768 | −0.135 | −0.232 | −0.00531 / −0.00913 |
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 e8
e8 denotes a shaft tolerance zone with running clearance deviation in the ISO 286 system. It is used in H8/e8 (Plain bearings in gearboxes and pumps, sliding gears, easily assembled couplings.) and H7/e8 (Coarser than H7/e7 for less critical plain bearings where the shaft is only held to IT8: conveyor rollers, agricultural machinery shafts.).
At Ø25 mm e8 is −0.040 / −0.073 mm, i.e. 24.927 to 24.960 mm.
How the limits are calculated
e8 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.