Northern Industrial Tools ARC 70 164620, Руководство оператора

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Northern Industrial Welder ARC 70
Operating Instructions and Parts Manual
9
It is important that the gap be
maintained during the welding
process and it should be neither too
wide or too narrow. If too narrow, the
rod will stick to the work piece. If too
wide, the arc will be extinguished.
It needs much practice to maintain
the gap. When the rod sticks to the
work piece, gently rock it back and
forth to separate them. A stuck
electrode will cause a short circuit
and the circuit breaker of thermal
overload will shut the welder off.
A good arc is accompanied by a crisp,
cracking sound. The sound is similar
to that made by bacon frying. To lay a
weld bead, only 2 movements are
required; downward and in the
direction the wel
d is to be
laid, as in
following figure:
2.3 Types of weld bead
The following paragraphs discuss the
most commonly used arc welding
beads.
The stringer bead Formed by
traveling with the torch in a straight
line while keeping the wire and nozzle
centered over the weld joint.
The weave bead Used when you
want to deposit metal over a wider
space than would be possible with a
stringer bead. It is made by weaving
from side to side while moving with
the torch. It is best to hesitate
momentarily at each side before
weaving back the other way
penetration.
2.4 Welding position
Flat position
It is easiest of the
welding positions and is most
commonly used. It is best if you can
weld in the flat position if at all
possible as good results are easier to
achieve.
The horizontal position it is
performed very much the same as
the flat weld except that the angle is
different such that the electrode, and
therefore the arc force, is directed
more toward the metal above the
weld joint. This more direct angle
helps prevent the weld puddle from
running downward while still allowing
slow enough travel speed to achieve