Catalog FATH US Industrial Hardware 3.0 - Catalog - Page 329
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DIMENSIONAL TOLERANCES (Excerpt from FATH norm 0055)
1.3 Tolerances for Materials Not Specified in this Standard
For materials not specified in this standard the general tolerances
from section 1.1 apply.
Deviant tolerances are declarated in the drawing.
1.4 General Information about Tolerances at FATH
(…)
1.4.2 Tolerances on dimensions and shapes as well as on surfaces
are to regard each separately (Principle of Independence according
to EN ISO 8015)
1.4.3 CAD data sets and drawings, except for asymmetric tolerance
specifications, comply with the nominal geometry dimensions.
1.4.4 All dimensions with general tolerances are excluded from the
test report.
For plastic parts, DIN EN ISO 291 defines a standard climate for
measuring: 23 °C ± 2 K und 50 % ± 10 % relative air humidity.
In the title block:
“Tolerances according to ISO 8015 (AD) – DIN EN ISO 291:2008-08“
is indicated.
1.4.5 For the measurement of radii, 90° or more of the circle segment has to be accessible for measurement.
1.4.6 Positional tolerances are no general tolerances. If functionality requires so, these are indicated directly in the drawing and have
to be measured.
1.5 Rejection
“Unless otherwise stated, workpieces exceeding the general
tolerance shall not lead to automatic rejection provided that the
ability of the workpiece to function is not impaired. The tolerance
the function allows is often greater than the general tolerance.
The function of the part is, therefore, not always impaired when
the general tolerance is (occasionally) exceeded at any feature of
the workpiece. Exceeding the general tolerance should lead to a
rejection of the workpiece only if the function is impaired.”
(DIN ISO 2768 – issue 04.91)
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SOLUTIONS FOR INDUSTRIAL ECOSYSTEMS
