Crown CT33123 Original Instructions Manual page 18

• mode to adjust the gas purging time after welding
(POST FLOW) - gas purging after welding allows
the end of the welding seam to cool down gradually,
preventing cracking and the formation of oxides�
When this mode is selected, indicators 21 and 12
are lit� To change this parameter, turn regulator 17
(the set value will be shown on display 14)�
Button A (welding current adjustment)
Button 19 (A) allows to switch from the adjustment of
other parameters to the welding current adjustment for
both the TIG and MMA welding modes� In the welding
current adjustment mode, indicators 10 and 18 are
lit� To change this parameter, turn regulator 17 (the
set value will be shown on display 14)� The welding
current magnitude depends on the works performed,
thickness of workpieces to be welded, an electrode
diameter, etc�
Recommendations on the machine op-
eration
Preliminary works (see fig. 7)
• Clean welding surfaces from rust and paint coatings�
• The edges of pieces to be welded should be ma-
chined if welding blanks width is more than 1 mm (see
fig. 7.1).
• Please remember that a large quantity of heat is
released during welding which can damage the sur-
rounding items, therefore, carefully choose the site
and take appropriate actions to prevent fire.
Electrodes
The right choice of electrodes, to a great extent, pre-
determines the welding seam quality and the operation
speed� Before purchasing
examine the recommendations of their use� Consult a
specialist if necessary� It is also important to observe
the electrode storage conditions�
General operation recommendations
The recommendations below apply to all
machines connected through a socket
connector. In the case of stationary con-
nection the machine assembly and net-
work connection will be done beforehand.
• Place the machine in an even, dry, not vibrating
surface observing all above-mentioned safety proce-
dures�
• Connect the ground wire�
TIG welding (see fig. 7)
• Connect gas feeding, earth terminal cable, and
welding torch to the machine� Connect earth clamp 41
to socket "+" 5�
• Fix earth clamp 41 on one of the parts to be weld-
ed�
• Connect the machine to the mains and switch it on�
• Select the TIG welding mode as described above�
• Slightly open the valve of gas pressure regulator 53
and turn on the valve of gas cylinder 55� Push and
hold button of welding torch 42, gas will come from a
electrodes, carefully
English
ceramic torch nozzle 43; using the valve of gas pres-
sure regulator 53, set gas flow rate (l/min), necessary
for work performance; release the button of welding
torch 42�
• Set the welding current value�
• Adjust other process parameters as described
above, if necessary�
• Turn on welding torch 42 (as described above) and
light the arc:
• for the high-frequency ignition of the arc, bring
torch 42 to workpieces to be welded and hold it so
that the distance between tungsten electrode 61 and
a workpiece is 2-4 mm - a high-frequency discharge
will ignite the welding arc;
• for the contact ignition of the arc, touch the
workpiece with an end of tungsten electrode 61,
then slightly tilt and raise torch 42 until a 2-3 mm gap
forms between a tip of tungsten electrode 61 and the
workpiece - at this moment a welding arc will form�
• If you weld workpieces thicker than 1 mm, a rod of
proper diameter should be fed in arc burning area for
filling a welding seam.
• Hold welding torch 42 and a rod, as illustrated in
figures 7.2 and 7.3 (grey arrow shows a direction of
welding torch movement)� Move the welding torch 42
and rod along a welding seam, delivering a filler rod, as
it's consumed, in welding point�
• After completion of welding, release the button of
welding torch 42, but don't remove it, wait for crater filling
and cooling down of the shielding gas welding end�
• After completion of work, machine should cool down,
then disconnect it and close valve of gas pressure
regulator 53 and valve of gas cylinder 55�
MMA welding (see fig. 8)
When describing MMA welding, elec-
trodes mean stick consumable elec-
trodes having coatings.
• Connect the welding cables to the machine� Weld-
ing can be performed with direct and reverse polarity�
The selection of polarity depends on the materials to
be welded and the recommendations on how to use
electrodes�
• Direct polarity - connect electrode holder 40 to
socket "-" 8, connect earth clamp 41 to socket "+" 5�
In such a mode the electrode heats less than the
basic metal, the electrodes get fused slower, the
welding joint is completed with a deeper penetration�
• Reverse polarity - connect electrode holder 40 to
socket "+" 5, connect earth clamp 41 to socket "-" 8�
In such a mode the work piece is heated less than
the electrode which can be used for welding high-
carbon, alloy and special steels sensitive to over-
heat as well as for welding sheet metal�
• Press the lever of the electrode holder 40 and install
the electrode end (the end free from coating) into elec-
trode holder 40 and then release the lever�
• Fix earth clamp 41 on one of the parts to be welded�
• Connect the machine to the mains and switch it on�
• Select the MMA welding mode as described above�
• Set the welding current value� The selection of
welding current depends on the electrode to be used,
thickness of material to be welded, spatial position of
a seam etc�
• Ignite the welding arc in one of two ways: ignition
by touching (see fig. 8.1); ignition by scratching (see
fig. 8.2).
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