Setting At Work - ELLETRO PLASMA Manual De Instrucciones

dented pin cannot be disconnected, once fit from the fixed fitting
R (fig. 1) a bent pin prevents the adapter from being correctly
mounted on the fixed fitting R (pic.1) and the unit from working.
This machine is suitable only for genuine torches type
P 150, either manual or automatic and producers do not
assume any responsibility in case that a different kind of
torch is used.
N.B. Never lift the machine by the handle.

3.2 SETTING AT WORK

The unit must be installed by skilled personnel. All fittings
must be in conformity with the existing rules and in full
compliance with safety regulations. Connect the air feed to
fitting on the air pressure reduction unit I (pict. 2) making sure
that pressure is 88PSI (6bar or KPaX100) at least with a minimal
capacity of 420 CFH (200 litres/min). Should air feed come from
a pressure reducing unit of a compressor or of a centralised
plant, the reducing unit should be adjusted at the highest out put
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 regulator; never connect
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. Connect supply cable L
(pic.2) the yellow-green wire of cable must be connected to an
efficient earth plug of the system, the remaining wires should be,
connected to the feed line by means of the switch placed, if
possible, close to the cutting area so as to switch the unit off
quickly if necessary. The magnetothermic switch capacity or of
fuses in series with switch should be equal or above the current
I absorbed by the unit. Current I
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the technical specifications on the unit i.e. feed voltage U
available. Any extensions should have adequate sections for
current absorbed I .
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3.3 USE
Switch the unit on by turning knob A (pict. 2) of the mains switch;
this is shown by light B (pict.1) 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 (4,5÷4,7 bar or KPaX100), otherwise
adjust it by means of knob of 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).
Aluminium: up to 3/4 mm 40/50A position;
up to 8/10 mm 80/90A position;
up to 15/18mm 110/120A position;
up to 22/25 mm 150A position.
Stainless steel and mild steel:
up to 5 mm 40/50A position;
up to 12 mm 80/90 A position;
up to 25 mm 110/120A position;
up to 35 mm 150A position.
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.
Clean the work piece to ensure good electrical contact of the
work clamp. Do not connect work clamp to the material to be
removed. Press torch button to start pilot arc, if cutting does not
absorbed is known by reading
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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. Should holes be drilled or should the piece be cut
starting from its centre, torch should be tilted and then slowly
straighten to prevent molten metal from being spread on
nozzle (see picture4). This operation should be carried out
with material 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 calliper (supplied on request).
N.B. : Avoid keeping pilot arc uselessly on, in air to avoid
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
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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
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and thickness.)
Work clamp not properly in electric contact with piece.
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Worn nozzle and electrode.
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Too low cutting current.
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N.B. : When the unit does not thoroughly pass through, nozzle
is clogged by scums.
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2) Cutting arc switches off.
This may be due to:
Worn nozzle, electrode or diffuser.
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− Too high air pressure.
Too low feed voltage.
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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
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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
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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
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degreased.
To avoid damage of torch always use original spares.
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