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The welder will put on his/her individual protective equipment
using a welding mask or helmet that is suitable for the work and
suitably covering any portion of his/her skin to avoid splashes or
radiation.
Welding shall be started by priming the arch. There are several
proceedings, the simplest of which is scratching the piece.
Once the arc has commenced, the electrode shall be kept at a
distance approximately equal to the diameter of the electrode
itself, and advancing of the weld shall be commenced by drawing
backwards as if a right-handed occidental person started writing,
The electrode shall be held in a position close (65o to 80o) to
the vertical with respect to the horizontal and balanced with
respect to weld puddle center. Depending on the kind of weld
pass (initial or filling) and the need of covering the joint, advance
in a straight line, zigzag movement or small circles. Good setting
of intensity, position and advance speed of the weld will result
in a pleasant, gentle sound, similar to that of a good barbecue
roast. When performing an accurate work, the resulting bead will
be homogeneous, with uniform surface marks shaped as half
moons.
Once the bead has been made, remove slag with a hammer and
brush before making the subsequent bead.

4.5.2.- TIG welding

In electric arc welding by means of an inert-gas-protected
tungsten electrode, the consumable material is not the electrode
itself but a filler rod of a material similar to, or compatible with
the material to be welded. Compared with the shielded electrode
system, this system has greater productivity and greater
difficulty in exchange for very high weld quality regarding almost
any metal and alloys thereof, including all stainless steels and
situations of joints of low thickness with or without filler material.
Welding takes place without slag, projections or smoke.
Do neither use nor sharpen thorium-doped tungsten
electrodes with a red mark, because of the risk
derived from the moderate radioactive activity of
the material. You may recognize the presence and
concentration of thorium dioxide by the indicative strip on
the electrode according to EN ISO 68848:2004 (colors:
yellow, red, purple and orange). Avoid these electrodes and
use substitute products without contents as for example
electrodes with lanthanum and cerium derivatives (strips:
black, grey, blue, gold) which do not have radioactive
activity.
Prepare the electrode by sharpening the tip with the emery stone
in such a way that a cone with a height of approximately 2 times
the electrode's diameter remains. For a better arc and current
handling capacity, the correct attack of the tip on the stone must
be longitudinal and the tip must be slightly flat.
In order to correctly position the electrode in the torch, it must
protrude about 5 mm above the nozzle.
As a general rule, connect the output inversely than the usual
connection of the electrode i.e. the TIG torch to the equipment's
negative terminal and the grounding clamp to the positive
terminal. Prepare and secure the piece.
As a general rule, supply pure argon at a flow of 6-7 l / minutes.
Adjust current intensity in accordance with the needs of the kind
of material and the joint to be made, making first a test on a test
piece. Refer to tables 5 and 6, specialized literature or regulated
professional training for further information in respect hereof.
ENGLISH
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The torch shall receive inert gas supply (usually pure argon)
proceeding from a cylinder, through a pressure reducing system
capable of suitably regulating the necessary gas flow volume.
Models TIG AC/DC 200HF y TIG AC/DC 315 HF present
features of maximum professionalism as explained in chapter
"advanced TIG welding".
Model PROGRESS 1700 L requires a TIG torch (not included,
STAYER references 38.71 and 38.73) with a direct connection to
the flow meter and as control by a flow valve that is incorporated
in the TIG torch itself.
Except for model PROGRESS 1700 L, internal start and stop
control is incorporated, so that the gas flow is governed internally
by means of the control pushbutton of the TIG torch.
In the PROGRESS 1700L, it is necessary to use a torch with
manual valve on the handle.
The TIG DC 200 HF P model presents the advantage of having
the commutator of selection 2T / 4T in order not to hold the
trigger down in the position 4T.
Model PROGRESS 1700 L has the improved feature of a
touch start system (Lift Arc). This system allows for a minimum
electrode contamination. To start TIG welding, move switch 7
to position TIG, open the gas outlet valve and put the tip of the
torch in contact with the piece to be welded. Wait two seconds
and then slowly raise the torch slowly to make the arc to start
automatically and smoothly.
The remaining models have HF (High Frequency) priming with a
maximum priming quality as they do not need to have physical
contact with the piece so that the conditions of the arc and welding
are not deteriorated by contamination of the tungsten electrode.
To start TIG welding, move switch 7 to position TIG and simply
move the tip about 3-5mm close to the piece to be welded. Press
the pushbutton of the torch to strike the arc automatically. Should
there be starting difficulties, you may slightly lean the ceramic
nozzle against the piece to facilitate priming of the electrode.
Once the welding arc has been struck, proceed to carrying out
welding in accordance with the needs thereof. As a general
orientation, you shall have to advance inversely to electrode
welding such that, instead of drawing backwards, you act
pushing forwards as if you helped the gas flow to act on the weld
puddle.
Slowly deposit the filler material of the rod by successively
bringing it closer to the puddle of fused material. To finish, simply
stop pushing the switch of the torch, separate the torch very
slightly until the arc is interrupted and close the manual gas
flow valve. Finally, close the general flow valve of the inert gas
cylinder.
The POTENZA TIG 170 HF includes two adjustments of welding
end:
1.
The 11 "Down Time" control stablishes a current ramp down
when welding stops. The ramp starts in the selected work
intensity and it finishes at zero amps. The duration time of
the ramp (from 0 to 5 seconds) is what it is adjusted with
the control. The aim is having a soft arc stop and a precise
control of the crater point of the end of the cord. As a general
rule, increase the time with increasing welding amperage.
2.
The 12 "Post Time" control stablishes the time (from 0,5 to
7 seconds) of additional gas outlet (argon) after finishing de
welding arc. The aim is that the weld is not be polluted with
the air when it is liquid or too hot. As a general rule, increase
the time with increasing welding amperage.
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