ESAB Fabricator 252i, Руководство по эксплуатации

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ESAB FABRICATOR 252i
Manual 0-5423 4-3 BASIC WELDING
Art # A-08999_AC
Nozzle Angle, Right Handed Operator
Direction of Gun Travel
Leading or “Pushing”
Angle
(Forward Pointing)
Trailing or “Pulling”
Angle
(Backward Pointing)
90°
Figure 4-10
Establishing the Arc and Making Weld Beads
Before attempting to weld on a finished piece of work, it is
recommended that practice welds be made on a sample metal of
the same material as that of the finished piece.
The easiest welding procedure for the beginner to experiment
with MIG welding is the flat position. The equipment is capable of
flat, vertical and overhead positions.
For practicing MIG welding, secure some pieces of 1/16" or
3/16" (1.6 mm or 5.0 mm) mild steel plate 6" x 6" (150 mm x
150 mm). Use .035" (0.9 mm) flux cored gasless wire or a solid
wire with shielding gas.
Setting of the Power Source
Power source and Wirefeeder setting requires some practice by
the operator, as the welding plant has two control settings that
have to balance. These are the Wirespeed control (refer to section
3.06.4) and the welding Voltage Control (refer to section 3.06.10).
The welding current is determined by the Wirespeed control, the
current will increase with increased Wirespeed, resulting in a
shorter arc. Less wire speed will reduce the current and lengthen
the arc. Increasing the welding voltage hardly alters the current
level, but lengthens the arc. By decreasing the voltage, a shorter
arc is obtained with a little change in current level.
When changing to a different electrode wire diameter, different
control settings are required. A thinner electrode wire needs
more Wirespeed to achieve the same current level.
A satisfactory weld cannot be obtained if the Wirespeed and Volt-
age settings are not adjusted to suit the electrode wire diameter
and the dimensions of the work piece.
If the Wirespeed is too high for the welding voltage, “stubbing”
will occur as the wire dips into the molten pool and does not
melt. Welding in these conditions normally produces a poor
weld due to lack of fusion. If, however, the welding voltage is too
high, large drops will form on the end of the wire, causing spat-
ter. The correct setting of voltage and Wirespeed can be seen
in the shape of the weld deposit and heard by a smooth regular
arc sound. Refer to the Weld Guide located on the inside of the
wirefeed compartment door for setup information.
Electrode Wire Size Selection
The choice of Electrode wire size and shielding gas used de-
pends on the following:
• Thickness of the metal to be welded
• Type of joint
• Capacity of the wire feed unit and Power Source
• The amount of penetration required
• The deposition rate required
• The bead profile desired
• The position of welding
• Cost of the wire