Tolerance accuracy

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 mm20030050080010001200150020002500
DIN 876 / III485260728088100120140
DIN 876 / II 242630364044506070
DIN 876 / I121315182022253035
DIN 876 / 04,85,267,288,8101214
L mm300035004000450050005500600065007000
DIN 876 / III160180200220240260280300320
DIN 876 / II 8090100110120130140150160
DIN 876 / I404550556065707580
DIN 876 / 0161820222426283032

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

Spacing tolerances for threaded drill holes a

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

Spacing tolerances for fitment bores a

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.