Tabla de contenido
Publicidad
Idiomas disponibles
Idiomas disponibles
SHORT CIRCUIT PROTECTION
FUNCTION
• In the event that the electrode touches the
workpiece during welding for more than 2s,
the current will drop to 0 in 1s to protect the
electrode.
QUALITY OF THE WELD
The quality of the weld will depend mainly on
the ability of the welder, on the type of weld
and on the quality of the electrode: Choose
the proper electrode before attempting to
weld, paying attention to the thickness and
composition of the metal to be welded.
Correct welding current.
If the current is too high the electrode will burn
fast and the weld pool will be wide irregular
and difficult to be controlled. If the current is
too low you will lack power and the weld pool
will be narrow and irregular.
Correct arc length.
If the arc is too long it will cause spatters and
small fusion of the welding piece. If the arc is
too short the arc heat will be insufficient cau-
sing the electrode to stick to the workpiece.
Correct welding speed.
The correct welding speed will consent to
achieve a weld of proper width, without wa-
ves or craters.
WELDING WITH INFUSIBLE
ELECTRODE (AC/DC TIG)
TIG welding with direct current (DC) is speci-
fically used to weld steel and stainless steel.
For these types of welding, it is advisable to
use no pure tungsten electrodes (not green).
The tip of the infusible electrode is tapered so
that the arc is stable and the energy is con-
centrated on the contact point/area which is
to be welded. The length of the tapering will
depend on the diameter of the electrode: with
low current, tapered tip with tapering length
l = 3 x d; with high current, rounded tip with
tapering length l = 1 x d.
Fig. 14
TIG welding with alternating current (AC) is
specifically used to weld aluminum and its
alloys by using pure tungsten infusible elec-
trodes.
During welding in alternating current (AC) the
ratio between the positive and negative half-
cycle of the current is called "balance." By va-
rying the value of the wave balance (key 12)
varies thermal effort between the infusible
tungsten electrode and the workpiece:
• the higher the wave balance value, the
higher the time of the positive half-wave
than the time of the negative half-wave.;
in this case the heat is more concentra-
ted on the electrode than on the piece to
be welded; The result is a pickling action
(cleaning) on the bath (bead) in welding;
• the lower the wave balance value, the
shorter the time of positive half-wave than
the time of the negative half-wave;.the
heat is more concentrated on the piece
than on the electrode;
• the operator has to calibrate the balance
of the wave in function of the diameter of
the infusible electrode in use, of the value
of the welding current, of the thickness
and material of the workpiece to be wel-
ded, and of alloy type and related oxida-
tion;
The triggering of the arc in TIG is performed
with peaks of high voltage at high frequency;
this solution (HF system) does not require
contact between the electrode and the piece
in order to trigger the welding arc.
COMPLETING THE TIG SYSTEM WITH
AN AIR COOLING TORCH
• Connect the ground lead to the positive
(+) socket of the generator (pos. 5) and the
ground clamp to the piece which is to be wel-
ded.
• Connect the power cable of the torch to the
negative (-) socket of the generator (pos. 4).
• Connect the torch button cable connector
to the socket on the generator (pos. 7) (pin
1 and 2).
• Connect the gas hose connector of the
torch to the gas connector on the generator
(pos.6).
• Connect the gas tube to the "gas connec-
tion" located on the rear panel of the gene-
rator (pos. C) and to the pressure reducer
assembled on the suitably fixed cylinder.
EN-11
Publicidad
Tabla de contenido
