Thermal Arc 281 FABRICATOR, Руководство по обслуживанию

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FABRICATOR 281
Manual No. 0-4880B 4-11 OPERATION
4.05 MIG Gun Maintenance
Remove dust and metallic particles from the gun conduit by forcing clean, dry compressed air into the conduit once
a week. This will minimize wire feeding problems.
4.06 Basic Welding Technique
Setting of the Power Supply
The setting of the Fabricator 281 requires some practice by the operator, the welding Power Supply having two
control settings that have to balance. These are the Wire Speed control and the Voltage Control switches. The
welding current is determined by the Wire Speed control, the current will increase with increased Wire Speed,
resulting in a shorter arc. Less wire speed will reduce the current and lengthen the arc. Increasing the welding
voltage hardly alters the welding current level, but lengthens the arc. By decreasing the voltage, a shorter arc is
obtained with little change in welding current.
When changing to a different electrode wire diameter, different control settings are required. A thinner electrode
wire needs more Wire Speed to achieve the same current level.
A satisfactory weld cannot be obtained if the wire speed and voltage switch settings are not adjusted to suit the
electrode wire diameter and dimensions of the work piece.
If the Wire Speed 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 electrode wire, causing spatter. The correct
setting of voltage and Wire Speed can be seen in the shape of the weld deposit and heard by a smooth regular arc
sound.
MIG Gun Travel Speed
Speed at which a weld travels influences the width of the weld and penetration of the welding run.
Position of MIG gun
The angle of MIG gun to the weld has an effect on the width of the weld run. Refer to Figure 4-13.
Art # A-05148
Forehand Vertical
Figure 4-13: MIG Gun Angle