WELDING OPERATIONS I - OD1651 - LESSON 1/TASK 1
(d) When welding upward, the electrode should be held at 90
degrees to the vertical as shown in figure 20, view B, on the
previous page. When welding upward and weaving is necessary, the
electrode should be oscillated as shown in figure 20, view C.
(e) When welding downward, the outer end of the electrode
should be inclined downward about 15 degrees from the horizontal
with the arc pointing upward toward the deposited molten metal as
shown in figure 20, view D.
When welding downward, in the
vertical position, and a weave bead is required, the electrode
should be oscillated as shown in figure 20, view E.
(f) When depositing a bead weld in the horizontal direction on
a vertical plate, the electrode should be held at right angles to
the vertical as shown in figure 21, view A, on the following page
and tilted 15 degrees toward the direction of welding so as to
provide a better view of the arc and crater.
(2) Butt Joints.
(a) Butt joints on plates in the vertical position are prepared
for welding in the same way as those required for butt joints in
the flat position.
(b) In order to obtain good fusion and penetration with no
undercutting, a short arc should be held and the motion of the
arc should be carefully controlled.
(c) Butt joints on beveled plates 1/4 inch thick can be made by
using a triangular weave motion as shown in figure 21, view B.
Welds on 1/2 inch plate or heavier should be made in several
passes as shown in figure 21, view C.
The last pass should be
deposited with a semicircular weaving motion with a slight whip-
up and pause to the electrode at the edge of the bead.
(d) When welding butt joints in the horizontal direction on
vertical plates, a short arc is necessary at all times and the
metal is deposited in multipass beads as shown in figure 21, view
D. The first pass is made with the electrode held at 90 degrees
to the vertical plates. The second, third, and subsequent passes
are made with the
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