EuroWire March 2016

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4-8 April
March 2016 173
wire 2016 show
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Here it is extremely important that a
uniform cross-linking over the entire
production run is achieved or, respectively,
that the product has a uniform cell
structure and a regular result of foaming.
Mixing station systems are required when
precise dosing is necessary over the
complete speed range of the extruder,
if very small amounts/percentages of
additives are to be dosed or if non-visible
additives are to be handled.
Depending on the requirements there are
various systems/solutions available. As
each manufacturing requires individual
solutions, it is recommended that speci c
solutions are worked out, in order to get
the best results.
In cable manufacturing nowadays it is
common to make use of mixing station
systems. In these types of systems all
materials are dosed and thus controlled.
Mixing stations work fully independently
of the extruder speed and material
consumption.
Since the end of the 1970s, Woywod
Kunststo maschinen has continously
developed this technology and supplied
reliable and high quality Plasticolor
equipment to the market, which meets the
requirements of the various customers.
Woywod o ers two main versions of the
mixing stations:
• Plasticolor volumetric mixing stations
and
• Plasticolor gravimetric mixing stations
(loss-in-weight principle)
Plasticolor volumetric and gravimetric
mixing stations have the following
advantages:
• Very good handling of all plastic
materials, ranging from free- owing
powder to micro-granules, and to
coarse regrind
• Extremely precise dosing of each
individual component at any time of
production
• Experience has shown that this
precision is ±0.5 per cent or better.
It is to be noted that this precision is
not taken from the average of many
batches
• Very good handling, quick cleaning
and short changeover times
• Sticking to the preset recipe over the
full RPM range of the extrusion line
• Very homogeneous and good quality
of the mixture, also when having
di erent material densities and
varying material properties
• Low volume of pre-mixed material
Speci c advantages/disadvantages of
Plasticolor volumetric mixing stations are:
• Material calibration tests are necessary
• Comparatively low investment
Speci c advantages/disadvantages of
Plasticolor gravimetric “loss-in-weight”
mixing stations are:
• No material calibration tests are
necessary
• Slightly higher cost of investment
For special applications and for
the extrusion of special materials,
synchronised Plasticolor mixing stations
can be o ered. These systems provide a
constant material level in the neckpiece
and ensure that the amount of material
does not vary.
Woywod Kunststo maschinen GmbH &
Co – Germany
Website:
WTM
Stand: 11D78
WTM will display a new horizontal line
suitable for the production of coaxial
cables wrapped with copper silver-plated
tapes/wire.
The line is composed of pay-o and
take-up, caterpillar/capstan combined
pulling unit and a wrapping unit, which
is equipped with the latest generation
taping head for CuAg-coated tape.
Thanks to its high sensitivity dynamic
dancer, this triple motorised head is
particularly suitable for this kind of cable
because of the precise wrapping it grants.
The dynamic dancer is an active control
system that adjusts the tension in real
time, directly on the materials being
wrapped, applying the pre-set pulling
tension on the tape and keeping
it constant in any situation, including
when the tape is traversing from edge to
edge on the spool.
A further advantage of this line is to
be equipped with newly designed
single-shaft pay-o and take-up units:
they are traversing, self-aligning and
self-levelling in two axes and with a
technologically advanced torque control.
In combination with diameter laser control
and torque sensors, they allow cable
tension to be directly monitored and
adjusted in real time. With this advanced
adjustment system, no dancers are used,
▲ Newmachinery on o er fromWTM