Torch Maintenance - Elettro CF PLASMA 55 Manual De Instrucciones

unit should be adjusted at the highest output pressure which
should not exceed 120 PSI (8bar or KPa x100). Should air
feed come from a compressed air bottle, this should be
provided with a pressure
compressed air bottles directly to the reducing unit!
Pressure may exceed the reducing unit capacity and then
explode!
Check that the mains power supply matches that indicated on
the technical date plate of the machine. The change of
voltage (see pict. 3) is obtained by rotating the disk set under
the knob of the switch A (pict.1 – 1a).
Connecting supply cable L (pict. 2): the yellow-green wire
must be connected to an efficient earth plug of the system,
the remaining wires should be connected to a switch placed,
if possible, close to the cutting area so as to switch the unit
off quickly if necessary. The capacity of magnetothermic
switch or of fuses in series to the switch should be equal or
above the current I absorbed by the unit. The absorbed
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current I is indicated in the technical specifications on the
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unit close to input voltage U
should have adequate sections for absorbed current I
3.3 USE
Switch the unit on by turning knob A (pict.1 – 1a) of the mains
switch; this is shown by light B (pict.1 – 1a) which is on. By
pressing for a second the torch button, the compressed air
flow is opened. Check that, under this condition, the pressure
shown on gauge D (pict. 2) is about 75 PSI (4,7 bar or
KPaX100), otherwise adjust it by the knob of the reducing unit
I (pict. 2), then lock this knob by pressing it down. Connect
work clamp to the piece to be cut. Set the cutting current by
means of the knob H (pict.1 – 1a). Use the Ø 1 mm nozzle up
to 50A and the Ø 1,2 mm nozzle up to 70A.
N.B. Cut quality is greatly improved if the nozzle is kept at
a distance of approx. 2 mm from the workpiece. Often for
practical reasons, however, cutting is performed with the
nozzle in contact with the workpiece. Cutting with the
nozzle in contact with the workpiece must not be
performed at currents above 50A as this leads to rapid
(sometimes even instantaneous) destruction of the
nozzle hole; this in turn leads to poor cutting quality.
Clean the work piece to ensure good electrical contact of the
work clamp. Do not connect work clamp to the piece to be
removed. Press torch button to start pilot arc, if cutting does
not start after 4 seconds, the pilot arc turns off and the button
should be pressed again to repeat the operation. When
possible, the torch should be pulled. Pulling is easier than
pushing. Keep torch in vertical position when cutting. Once
cutting is over and after releasing button, air continues to flow
out of the torch for about 1 minute so it enables torch to cool
down. It is recommended not to turn the unit off before that
time. If you have do drill holes or to start the cut of the piece
from its centre, you should tilt the torch and then slowly
straighten it to prevent molten metal from being spread on
nozzle (see pict. 4). This operation should be carried out
when cutting pieces of thickness above 1/8" (3 mm). If you
have to cut near angles or recesses (see picture 5) it is
recommended to use extended electrodes and nozzles.
Should circular cut be done it is recommended to use caliper
(supplied on request).
N.B. : Avoid keeping pilot arc uselessly on in air, to avoid
regulator; never connect
available. Any extensions
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electrode, diffuser and nozzle consumption.
3.4 CUTTING TROUBLE
1) Insufficient penetration
This may be due to:
- high speed. Always make sure that arc thoroughly passes
through the piece to be cut and that it is not tilted, when going
forward, by a percentage above 10 ÷ 15° (see picture 6). It is
thus avoided to wear nozzle (see pict. 7) out and to burn the
nozzle holder (see picture 8).
- Excessive thickness of piece (see graph of cutting speed
and thickness).
- Work clamp not properly in electric contact with piece.
- Worn nozzle and electrode.
- Too low cutting current.
N.B. : When the unit does not thoroughly pass through,
scums clog nozzle.
2) Cutting arc switches off
This may be due to:
- worn nozzle, electrode or diffuser.
- too high air pressure.
- too low feed voltage.
3) Tilted cutting
When cutting is tilted (see picture 9) switch the unit off,
loosen nozzle holder and turn nozzle by a quarter turn, then
lock and try again.
Repeat until cutting is straight (see picture 10).
4) Excessive wear of consumable parts
This may be due to:
a) too low air pressure with respect to the recommended one.
b) excessive burns on the end part of nozzle holder.
3.5 PRACTICAL RECOMMENDATIONS
- If the system air contains much humidity and oil it is required
to use a drying filter to avoid excessive oxidation and wear of
consumable parts, to avoid torch damage or to reduce speed
and quality of cutting.
- Impurities of air favour oxidation of electrode and nozzle and
make it difficult to start pilot arc. If this occurs, clean the end
part of electrode and inside the nozzle with fine abrasive
paper.
- Make sure that new electrode and nozzle to fit are clean and
degreased.
- To avoid damage of torch, always use original spares.

3.6 TORCH MAINTENANCE

Always disconnect the unit before any repair of torch.
1) Replace wear parts (picture 11 – 11a)
The parts subject to wear are electrode A, diffuser B and
nozzle C. Either part may be only replaced after loosening
nozzle holder D.
Electrode A should be replaced when a 1/16" (1,5 mm) deep
central crater develops (see pict. 12).
ATTENTION! When unscrewing the electrode, do not
make sudden stresses but gradually force so as to have
the thread unlocked. Lubricate the thread of the new
electrode with silicone lubricant (supplied with the unit).
This new electrode is to be screwed in its housing and
locked without tightening.
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