Snap-On Plasma25, Руководство по эксплуатации

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4
I) Water trap
L) Light signalling air pressure is low
5 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 B making sure that pressure
is 88PSI (6bar or 0.6 MPa ) at least with a minimal
capacity of 5 CFM (140 liters/min).
The air fitting to be connected to the pressure regulator
must have a threaded portion no more than 1/4"-5/16"
long, since a longer thread may cause malfunctions
inside the reducer.
Should air feed come from a pressure reducing unit
of a compressor or of a centralized plant, the reducing
unit should be adjusted at the highest output pressure
which should not exceed 120 PSI (8bar or 0.8 MPa).
Should air feed come from a compressed air bottle, this
should be provided with a pressure regulator; never con-
nect 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 indicat-
ed on the rating plate of the machine.
Connect supply cable A : the yellow-green ground 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 to the current
I
1
absorbed by the unit.
Current I 1 absorbed is known by reading the tech-
nical specifications on the unit i.e. feed voltage U 1 avail-
able.
Any extensions should have adequate sections for cur-
rent absorbed I 1.
6 USE
Press the C switch.
By pressing and immediately releasing the torch button,
the compressed air flow is opened. Check that, under
this condition, the pressure shown on gauge
F
is about
65/70 PSI (4,5÷4,7 bar or 0.45÷0.47 MPa), otherwise
adjust it by means of knob E of reducing unit, then lock
this knob by pressing it down.
Connect work clamp
H
to the piece to be cut.
Cutting circuit should not be deliberately placed in
direct or indirect contact with protection wire if not in the
workpiece.
If earthing is deliberately made on the workpiece by
means of protection wire, the connection must be as
direct as possible, with the wire having a section at least
equal to the cutting return current wire and connected to
the piece being worked on, in the same place as the
return wire, using the return wire terminal or a second
earth terminal closeby.
All possible precautions must be taken in order to avoid
stray currents.
Clean the work piece to ensure good electrical contact of
the work clamp.
When possible, the torch should be pulled. Pulling is eas-
ier than pushing.
Keep torch in vertical position when cutting.
Once cutting is over and after releasing button, air con-
tinues to flow out of the torch for about 60 seconds 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 start-
ing from its center, torch should be tilted and then slow-
ly straighten to prevent molten metal from being spread
on nozzle (see picture 3). This operation should be car-
ried out with material thickness above 1/16"(2 mm).
Should circular cut be done it is recommended to use
caliper (supplied on request).
Avoid keeping pilot arc uselessly on, in air to avoid
electrode, diffuser and nozzle consumption. When you
have finished working, turn off the machine and hang the
torch by the hook provided.event molten metal from
being spread on nozzle (see picture 3). This operation
should be carried out with material thickness above
1/16"(2 mm).
Should circular cut be done it is recommended to use
caliper (supplied on request).
Avoid keeping pilot arc uselessly on, in air to
avoid electrode, diffuser and nozzle consumption.
When you have finished working, turn off the
machine and hang the torch by the hook provided.
7 CUTTING SPEED SCHEME
8 CUTTING TROUBLE
1) Insufficient penetration
This may be due to:
• high speed. Always make sure that arc thoroughly pass-
es through the piece to be cut and that it is not tilted,
when going forward, by a percentage above 10 - 15°
(see picture 4). It is thus avoided to wear nozzle (see
picture 5) out.
• Excessive thickness of piece (see graph of cutting
speed and thickness)
• Work clamp H not properly in electric contact with piece
• Worn nozzle and electrode
• Too low cutting current.
When the unit does not completely cut through, nozzle is
clogged by slag.
2)
Cutting arc switches off
2 1
0.5
1.0
1.5
2.0
2.5
m/min
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
1/8 1/4 3/8 1/2
inc.
5/8
3 4 5 6
mm
7 8
20
40
60
80
100
inc/min
120
140
160
180
200
220
240
INOX
AL
FE
25 A