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Welding
Data
ESSENTIALS
FOR PROPER WELDING PROCEDURES
- Correct electrode
size
- Correct current
- Correct arc
length or voltage
- Correct travel
speed
- Correct electrode
angle
Besides the steady
sizzling sound that a correct arc produces the shape of the molten
pool and the movement of the metal at the rear of the pool serve
as a guide in checking weld quality. In a correctly made deposit
the ripples produced on the bead will be uniform and the bead will
be smooth no overlaps or undercuts.
- CORRECT ELECTRODE
SIZE
The correct choice of electrode size involves consideration of
a variety of factors, such as the type, position, preparation
of the joint, the ability of the electrode to carry high current
values without injury to the weld metal or loss of deposition
efficiency, the mass of work metal and its ability to maintain
its original properties after welding, the characteristics of
the assembly with reference to effect stresses set up by heat
application, the practicability to heat treatment before and /
or after welding, the specific requirement before and / or after
welding, the specific requirements as to welding quality and cost
of achieving the desired results.
- CORRECT CURRENT
If current on equipment is too high or too low, you are certain
to be disappointed in your weld. If too high, the electrode melts
too fast and your molten pool is large and irregular, if too low,
there is nor enough heat to melt the base metal and your molten
pool will be small, will pile up, look irregular.
- CORRECT ARC
LENGTH
If the arc is too long or voltage too high the metal melts off
the electrode is large globules which wobble from side to side
as the arc wavers, giving a wide, spattered and irregular bead-with
poor fusion between original metal and deposited metal.
If the arc is too short, or voltage too low, there is not enough
heat to melt the base metal properly and the electrode quite often
sticks to the work, giving a high, uneven bead, having irregular
ripples with poor fusion.
- CORRECTTRAVEL
SPEED
When your speed is too fast your pool does not last long enough,
impurities an gas locked in. The bead in narrow and ripples pointed.
When speed is too slow the metal piles up, the bead is high and
wide with a rather straight ripple.
- CORRECT ELECTRODE
ANGLE
The
electrode angle is of particular importance in fillet welding
and deep groove welding. Generally speaking, when making a fillet
weld, the electrode should be held so that ir bisects the angle
between the plates (as shown at right) and is perpendicular to
the line of weld, if under cut occurs in the verticle member,
lower the angle of the arc and direct the arc toward the vertical
member.

Welding Data
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