Tig Welding - STAYER WELDING TIG AC/DC 190HF PULSED Manual De Instrucciones

4.5 General instructions for use
Before starting, make sure you read, understand and apply the
safety instructions and other instructions included in the present
manual.
Below you will find a series of general indications that will
allow you initiating yourself in the world of welding and working
efficiently. In the present manual, instructions are provided with
regard to the rudiments of shielded-electrode welding of relatively
moderate difficulty in execution and regarding TIG welding having
a relatively greater difficulty. Take into account that welding on
professional level is a qualified and specialized activity. For further
information, refer to specialized books and regulated professional
training courses.
4.5.1 Shielded electrode welding
In this class of electric arc welding, the electrode itself produces
heat in the form of an electric arc, the shielded environment,
and it improves the weld puddle and the filler metal itself as the
electrode's metal core progressively melts as welding is carried
out.
You have to choose the electrode (size and type) that is suitable
for carrying out the work to be performed. An electrode we
recommend due to its medium quality, suitability for most works
and for being easy to find, is the E-6013 electrode, popularly
known as the "rutile electrode". The material par excellence for
welding with shielded electrode is carbon steel. The following
table may serve you as an initial orientation for electing the kind
of electrode and operation amperage setting for a S275-type
medium carbon steel.
After having confirmed all safety measures and inspected the
equipment, cleaned, prepared and fastened the piece to be
welded, cables are connected according to the indications in the
tables. For the usual case of an E-6013 electrode, the output of
negative polarity (marked -) shall be connected to the piece by
means of the grounding clamp. The output of positive polarity
(marked +) shall be connected to the electrode carrier clamp
which shall have the working electrode connected to its bare end.
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
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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.
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 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
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