WCA September 2007

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Technologynews
Wire & Cable ASIA – September/October 2007 69
Steel wire which is drawn down to size,
starts from larger diameter rods. The rod
and intermediate diameter coiled wire
needs to be properly descaled prior to
being drawn, as ferrous oxides and other
impurities on the surface of the material
form and need to be removed, in order
to reduce die wear and to achieve a
good surface finish on the final wire
being processed.
There are two conventional methods to
remove the scale on the wire. The first
method is chemical descaling, which
uses liquid substances and chemicals
to remove the surface oxidation.
The second method uses mechanical
descalers to descale wire without the
addition of any chemicals, providing an
environmentally friendly yet effective
method of removing surface oxides on
wire and rod. This system can also be
used directly in line with the wire
drawing machine or wire former, which
increases production efficiency.
Mechanical descalers, offered by OMF
of Italy through Howar Equipment in
North America, use a system of
specially positioned tungsten carbide
or hardened steel rollers which bend
the wire in numerous axes in order to
‘deform’ and elongate the wire.
The elongation and bending causes the
brittle and stiff surface oxide to break
away from the softer and elastic wire.
Since the wire is bent in multiple
directions by each roller that is placed
in a different position and axis, the
oxide is able to be attacked no matter
where it lies on the circumference of
the wire.
Once out of the reverse-bending
section of the descaler, the wire is
further cleaned by one or two sets of
rotating and orbiting wire brushes,
which ensure that any residual surface
impurities are removed.
As a last step, the wire passes through
an air-jet cleaning nib, which clears
loose particles from the wire. The use
of the reverse-bending and brushing of
the wire leaves a wire which is clean
and free of surface oxides. The entire
mechanical descaling system can be
easily installed in-line with a wire
drawing or wire forming machine.
Howar Equipment Inc
– Canada
Fax: +1 905 738 2474
Email:
Website:
Mechanical wire descalers = no chemicals
FTTH additions
from Prysmian
Prysmian Cables & Systems launched
further additions to its growing Fibre-
to-the-Home (FTTH) product range at
CommunicAsia 2007 – Asia’s major
communications and IT exhibition
and conference which was held in
Singapore from June 19th-22nd.
Visitors got the chance to see the
latest advances in telecoms and IT
technology from 1,500 companies.
Prysmian Telecom Cables
& Systems – Italy
Email:
Website: