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The paper is focused
upon Betula pendula wood species, trying
a presentation suitable to impel the interest
of foresters and specialists from wood
industry, in order to rehabilitate the
status of this wood species, with restrictive
areal and to promote its utilization on
larger scale due to its properties.
The experimental research
studies were performed under industrial
conditions and they were focused upon:
(1) determination of the minimum power
which is necessary for milling and sanding,
(2) determination of the roughness of
processed surfaces, in order to establish
(3) the optimal processing schedules.
The roughness of surfaces
resulted after milling and sanding was
measured with the MicroProf optical device
from the Laboratory with RENAR accreditation
of Testing the Processing Accuracy of
the Faculty of Wood Industry, thus resulting
the optimum processing schedules, based
on the criterion of minimum roughness.
Measurements were performed
both for straight and profiled milling,
along and cross the grain, with different
types and diameters of the milling cutters,
for two different rotation speed values,
five feed speed values, five cutting depth
values and five cutting width values.
The best surface quality
was obtained for longitudinal milling,
both in the case of straight and profiled
milling. With straight milling, for the
same diameter of the milling cutter, better
results were obtained with the cutters
with detachable plates than with the ones
with fixed plates. With profiled milling,
the best surface quality was obtained
on the concave zones of the profile, at
high rotation speed and low feed speed.
The results concerning
the roughness of the sanded surfaces showed
the positive influence of moisturizing
the surfaces prior to sanding, when using
grit sizes up to 20. It was also established
that, grit sizes over 120 are not justified,
neither economically nor from the surface
quality point of view.
The thesis is concluded
with a special software created in DELPHI,
regarding the optimization of processing
schedules by milling and sanding, based
on the research results.
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