20
S30 TORCH
1.0 TECHNICAL DETAILS
2.0 INSTALLATION
The generator is fitted with a welding torch. The instructions
below refer to replacing a faulty torch and should be carried
out only by qualified personnel.
Switch off the power source.
3.0 SETTING UP FOR USE
Fig.1 Assemblaggio corpo torcia
Before starting work, it is necessary to carry out the following checks
and work:
1) Check that the generator is turned off.
2) Check that all the parts of the torch are working. For the various
parts that make up the torch body (Fig.1), the sequence of correct
assembly is 1-2-3-4-5.
3) To fit the electrode (No.2), use the key, taking care to avoid exces-
sive tightening that could damage the thread of the components.
The electrode must be unscrewed only after the post-cutting air
flow is finished, and therefore with the electrode itself cooled.
4) Check that the air diffuser, or "swirl-bush" (No.3) is working cor-
rectly, which must always show access holes free of obstruction;
the use of a defective air diffuser would cause overheating, with
consequent damage to the components of the torch body.
5) With the spare parts assembled, check that by screwing the outer
nozzle (No. 5) to the torch body the corresponding alarm on the
generator is cut off; finally check that by unscrewing the nozzle the
alarm is triggered; these checks should be carried out with the gene-
rator on, taking care not to press the torch button.
6) The compressed air used must be filtered and maintained at a high
level of purity; humid air, oil and other contaminative agents must
be removed, by making use of suitable driers and anti- oil filters.
Thus the torch is set up for the cutting operation.
In any case it is necessary to also follow what is shown in the in-
struction manual for the generator, above all in the paragraphs
"General precautions", "Connecting up" and "Normal maintenance".
4.0 USING THE TORCH
4.1 Inclination and speed of the torch during cutting
The torch is generally held perpendicular to the workpiece during all
the cutting phases; obviously, whenever it is required to carry out
chamfering or inclined cutting, the torch must be tilted to a suitable in-
clination.
The speed must be adjusted so that the outflow of the arc below the
workpiece is perpendicular (5-10 degrees of slope are acceptable).
A slow speed start is advisable to prevent spray of material
which could damage the tip.
4.1.1 Puncturing
In some cases it is necessary to puncture a hole in the material using
plasma cutting. In this way, the wear on the parts which are subject to
deterioration will be increased, and it becomes very important to try to
work to avoid the return of spray, which can be dangerous, especially
with sheet metal over 5 mm. thick.
We suggest starting with the torch inclined sideways, so as to
point the spray outside the cutting area, avoiding damage
and overheating of the torch body.
Immediately remove any material accumulated on the tip
or on the ceramic hood.
Caution: plasma cutting is a process with a high thermal
element, which takes both the piece to be cut and the end
parts of the torch to extremely high temperatures.
4.1.2 Circular cutting
For the preparation of flanges and opening holes, it is possible to use a
pair of compasses, equipped with rotating heads and movement on
wheels.
4.1.3 Practical advice
We advise igniting the pilot arc away from the workpiece, and then
moving near until the cutting arc is struck; striking a cutting arc repea-
tedly and directly by contact with the workpiece creates an increase in
temperature of the torch body.
Avoid turning off the generator before the end of the post-cut
cooling flow, to avoid overheating of the components of the
torch.
5.0 MAINTENANCE AND INSPECTION
With the S30 torch, the ignition of the pilot arc takes place by pneu-
matic distancing of the electrode from the tip; during the operation,
oxidized area are created on the two components, that can give igni-
tion problems.
The efficiency of the electrode is therefore not only determined by the
cutting time, but also by the number of starts of the pilot arc that are
made.
It is advisable to replace the electrode before the tungsten insert in the
point is completely worn out.
The tip has an average life similar to that of an electrode, and is repla-
ced when an irregular hole is present which is larger than the nominal
one (this can cause slanted cuts of poor quality).
Electrode and tip are replaced simultaneously to prolong their active life.
Working with electrode and tip which are too spoiled can cause dama-
ge to the torch body.
It is important to pay special attention to the fitting of the electrode and
tip in order not to irreparably damage the torch.
Principle of operation
Version
Protection device
Current (x = 100%)
Cutting voltage
Pilot arc current
Pilot arc voltage
Pressure
Setting the pressure switch
Air quantity
Plasma gas capacity (suction with 0.8 hole)
Pilot arc ignition without high frequency.
Single air
External nozzle not screwed signal
30A
90V
15A
120÷130V
5 bars
3.5 bar
100 Iitres/min
10-12 litres/min
