Surface precision tolerances
Surface Qualities:
- DIN 876 /III: shaved / milled
- DIN 876 /II: fine shaved / milled
- DIN 876 /I: fine milled
- DIN 876 /0: closely trimmed and touched up
Flatness Tolerances:
The flatness tolerances give the permissible deviation of the measuring area in µm over the entire length L of the longest edge of the plate at a reference temperature of 20 °C.
- DIN 876 /III = 40 + L : 25 = µm
- DIN 876 /II = 20 + L : 50 = µm
- DIN 876 /I = 10 + L : 100 = µm
- DIN 876 /0 = 4 + L : 250 = µm
The surfaces of cast products such as tooling plates, measuring plates, marking plates and surface plates are produced in accordance with DIN 876.
To measure the surface accuracy, the plates are laid onto at least three support points. The plate ribbing constructed for each application transfers the forces that occur during use into the support points to ensure that the deformation of the surfaces to be measured is as low and the surface accuracy as high as possible.
Tolerance Tables | L mm | 200 | 300 | 500 | 800 | 1000 | 1200 | 1500 | 2000 | 2500 |
|---|
| DIN 876 / III | 48 | 52 | 60 | 72 | 80 | 88 | 100 | 120 | 140 |
| DIN 876 / II | 24 | 26 | 30 | 36 | 40 | 44 | 50 | 60 | 70 |
| DIN 876 / I | 12 | 13 | 15 | 18 | 20 | 22 | 25 | 30 | 35 |
| DIN 876 / 0 | 4,8 | 5,2 | 6 | 7,2 | 8 | 8,8 | 10 | 12 | 14 |
| L mm | 3000 | 3500 | 4000 | 4500 | 5000 | 5500 | 6000 | 6500 | 7000 |
|---|
| DIN 876 / III | 160 | 180 | 200 | 220 | 240 | 260 | 280 | 300 | 320 |
| DIN 876 / II | 80 | 90 | 100 | 110 | 120 | 130 | 140 | 150 | 160 |
| DIN 876 / I | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
| DIN 876 / 0 | 16 | 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 |
Deviations in µm
- Spacing tolerances for threaded drill holes a
- Engine bed of a portal milling machine with connection surfaces and threaded drill holes for guide strips
| 0 - 2000 | ± 0,15 |
| 2000 - 4000 | ± 0,20 |
| 4000 - 6000 | ± 0,25 |
| 6000 - 8000 | ± 0,30 |
| (in mm) Other tolerances on request. |
- Spacing tolerances for fitment bores a
- Fitment bores in the plate surface
| 0 - 1000 | ± 0,05 |
| 1000 - 2000 | ± 0,08 |
| 2000 - 3000 | ± 0,10 |
| 3000 - 4000 | ± 0,12 |
| 4000 - 5000 | ± 0,13 |
| 5000 - 6000 | ± 0,15 |
| (in mm) Other tolerances on request. |
