Multiple Pass Welding - Craftsman 196.205690 Manual Del Usuario

angle
B (see HOLDING THE GUN - p.16) is
such that the wire, and therefore the arc force,
is directed more toward the metal above the
weld joint. This is to help prevent the weld
puddle from running downward while still
allowing slow enough travel speed to achieve
good penetration. A good starting point for
angle B is about 30 degrees DOWN from
being perpendicular to the work piece.
Figure 15. Horizontal Position
3. The VERTICAL POSITION (Figure 16) is
the next most difficult position. Pulling the
gun from top to bottom may be easier for
many people, but in some instances it can
be difficult to prevent the puddle from
running downward. Pushing the gun from
bottom to top may provide better puddle
control and allow slower rates of travel
speed to achieve deeper penetration. When
vertical welding, angle B (see HOLDING
THE GUN - p.16) is usually always kept at
zero, but angle A will generally range from 45
to 60 degrees to provide better puddle
control.
Figure 16. Vertical Position
]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 o?f the work piece. Angle A (see
HOLDING THE GUN - p.16) 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.
19