4.2.1 Sleeky Zone the entrance of cables
does not have to offer an excessive resistance to the entrance of the first
cylinder of the breaker or Craquer machine, with the object of clearing the
curling conferred to the TOW. The devices to center and widen must guide the
cables, distributing uniformly to the set of filaments to all the wide of the
tape, applying a smooth longitudinal uniform tension.
4.2.2 Heating Zone ,is composed by por heating plates
, that go placed one above the other. Between
both sets an opening of 1 mm generally stays, through where the material
passes.
The calibration of heating plates must be made necessarily in
such a way that they slightly iron the material so that there is a good and
uniform heat transference to the cable. The temperature of plates, the
alignment and distance among them, influence in the fiber conferring it the
metastable state, (latent or potential shrinking). To greater temperature,
greater shrinking.
Normally temperatures between 130 and 1500 Cs are used depending
of the machine type because the caloric power, environment, effectiveness of
the cooling band of the exit wick, speed of the machine influences in it.
Therefore an exact temperature cannot be recommended to obtain a same value of
shrinking between 2 machines, even if they are of the same model.
The temperature over 165° C derives a badly operation of the
machine. Also, the dirtiness of the plates with the TOW antistatic, will
have to be cleaned periodically, otherwise it will influence in such operation
( see cleaning paragraph)
4.2.2.1 Calibration of plates for suitable heat
transference, TOW must be always in contact with the heating plates. For this
aim it is necessary that the superior and inferior plates must be level out
with the transport rollers.
we give like an example, the calibration (leveling) of plates of
a Breaker Seydel 870 procedure and is applicable to the other models of this
mark. The procedure is the following one:
1. To turn on the switch to close plates (electrical board).
2. To relax chain of superior plate movement (it misadjusts of 2 to per to us
of subjection).
3. To turn on the switch to open plates.
4. The superior plate group must be aligned with the ceramic rollers of mall
pillows 2 and 3.
In order to verify and to regulate this one alignment, wires of tempered steel
of 1 mm of diameter are placed to the ceramic rollers as shown in the drawing
(they must have counterbalances in the ends to maintain them tense).
5. The superior plate's bolts became loose and the regulators
are adjusted so that the plates are aligned with the wires. The bolts are
adjusted.
6. Turn on the switch to close the plates and the superior plate's movement
chain has to be set.
7. To verify the correct plate damping, if it's defective change the springs
that are necessary.
8. Level inferior plates with the selected gauge (generally 1 mm).
With certain regularity the correct alignment of plates must be
checked with a gauge.
4.2.2.2 Enlargements Calibration It is not
possible to give an exact calibration of the enlargements for the Rompedoras or
Craquers machines by traction due to the variations in the engine power,
distances between cylinders, quality of the ceramicados inferior cylinders,
covering of the superior cylinders of polyurethane and its pressure. Normally
it is used approximately from 17% to 20% between plates to obtain from 18 to
22% of shrinking of a spinning HB. It is not advisable to stretch more than 24%
between plates.
4.2.3 Curling Zone: Denominated zone of work
curled camera where to the broken cable is curl.
Considering that the curled camera overheats after 15 minutes of
operation approximately, it is necessary a visual control, becasuse that it is
reason of loss in the intensity of the curling. This disadvantage must be
remedied by readjusting the pressure of the curling tongue-piece, watching that
the excessive pressure originates defects in the fiber.
Normally the Breakers, at sea level, have a continuous built-in vaporized
camera when coming out of zone of curly or crimpado . About that
and other forms of vaporization we will deal in point 4.2.
4.2.4 Tape cooling Zone the tape has a
relatively high temperature (approx 70° C) after the curling and breakage
processes, having therefore to be cooled, without that fact an uncontrolled
preshrinking (loss by shrinking) can be originated. This cooling takes place on
a perforated conveyor belt through which the air passes. Few curly produces a
tape with little cohesion. Lot of Curled "acartona" the fiber doing it's
opening more difficult in the following passages
An additional cool tape device of this type can be obtained for
all the breaker machines. As an additional precaution measurement we
recommended to deposit tapes preferably in perforated aluminum containers.
These are better conductors of the residual heat to the surface, diminishing
the shrinking potential. The tapes temperature within the containers would not
have to exceed 60°C. At the present time perforated teflón boats are also used,
which are light and easy to arm.
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