Recomandations; Limit Values For Dtest - Wohler DTEST Notice D'utilisation

Dust surface density / level of cleanliness in air ducts and air-guiding surfaces
4.7

Recomandations

A: Evaluation with a test cloth per
100 cm² surface of a magnetic
disk:
B: Evaluation with a test cloth for
several 100 cm² magnetic disk
surfaces:
4.8

Limit values for DTEST

Acceptable level of dust concentra-
tion to VDI 6022 Part 1.3: 2015:
Determine the difference in mass by subtract-
•
ing the starting weight from the final weight of
every test cloth:
• To obtain the level of cleanliness, multiply the
difference in mass by the surface factor 100.
NOTE!
Level of cleanliness [g/m²] = mass
• Compare the result with the relevant limit
value.
To obtain the level of cleanliness, multiply the
•
difference in mass by the surface factor 100
and then divide the result by the number of
measured surfaces.
NOTE!
Level of cleanliness [g/m²] =
mass x 100/number of surfaces.
weighed
NOTE!
Document the taking of samples with images.
Upper limit Value of
value – successful
cleaning is cleaning
required
2
4.0 g/m 2.0 g/m
VDI 6022 1.3 assumes that a cleaned surface has
the same dust level as a new component.
NOTE!
Choosing the right sampling points has
a far greater effect on the accuracy of the
measuring process than the method of
measurement itself.
x 100.
weighed
Value of
news com-
ponents
before put-
ting into
operation
2 2
2.0 g/m
EN
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