Forney MIG 180FI, Руководство по эксплуатации

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WARNING
Hot slag can cause fires and serious injury
from burns! Be sure to wear protective cloth-
ing and eye gear when using the Overhead
Position.
4. The OVERHEAD POSITION (Figure 17) is
the most difficult welding position because
gravity is pulling at the weld puddle trying to
make it drip off the work piece. Angle A (see
HOLDING THE GUN - p.19) should be main-
tained at 60 degrees, the same as in the flat
position. Maintaining this angle will reduce
the chances of molten metal falling into the
nozzle should it drip from the weld puddle.
Angle B should be held at zero degrees so
that the wire is aiming directly into the weld
joint. If you experience excessive dripping of
the weld puddle, select a lower heat setting.
Also, the weave bead tends to work better
than the stringer bead when welding
overhead.
Figure 17. Overhead Position
MULTIPLE PASS WELDING
Butt Weld Joints. When butt welding thicker
materials, you will need to prepare the edges
of the material to be joined by grinding a
bevel on the edge of one or both pieces of
the metal being joined. When this is done, a
V is created between the two pieces of
metal, that will have to be welded closed. In
most cases more than one pass or bead will
need to be laid into the joint to close the V .
Laying more than one bead into the same
weld joint is known as a multiple-pass weld.
The illustrations in Figure 18 show the
sequence for laying multiple pass beads into
a single V butt joint.
NOTE: WHEN USING SELF-SHIELDING
FLUX-CORE WIRE it is very important to
thoroughly chip and brush the slag off each
completed weld bead before making another
pass or the next pass will be of poor quality.
Figure 18. Butt Joints
Fillet Weld Joints. Most fillet weld joints, on
metals of moderate to heavy thickness, will
require multiple pass welds to produce a
strong joint. The illustrations in Figure 19
show the sequence of laying multiple pass
beads into a T fillet joint and a lap fillet joint.
Figure 19. Fillet Weld Joints
SPECIAL WELDING METHODS
SPOT WELDING
The purpose of a spot weld is to join pieces
of metal together with a spot of weld instead
of a continuous weld bead. There are three
methods of spot welding: Burn-Through,