Mosa DSP 2x400 PSX, Инструкция по эксплуатации и обслуживанию, каталог запасных частей

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USE WELDING DIGITAL CONTROL
M
33.
3
© MOSA 1.0-10/04
WIRE WELDING with constant voltage (C.V.)
“Wire welding” can be performed in two modes:
”short arc” or “spray arc.”
TERMS
1) “ Short ” refers to the way of transferring the
material (wire) to the work piece.
In this case, each time a drop of molten material
is formed at the tip of the wire, assuming that the
rod continues to advance, the tip touches the
molten weld pool and is combined with it,
provoking a very brief short circuit - hence the
term “Short” is commonly used.
2) “ Spray ” refers to the transfer of material in the
form of tiny molten droplets which, by means of
the arc itself, pass into the molten weld pool as if
they were sprayed by the arc.
“ Short arc ” welding requires a much lower arc
voltage than “spray arc,” on the order of 25% less.
The passage from “short arc” to “spray arc” occurs
automatically by setting a higher operating voltage,
if using inert gases or a mixture of gases, but not
with pure CO
2
. With pure CO
2
the “spray arc” occurs
only in part and, in any case, over a wide area
resulting in excessive splatter.
“
Short arc ” welding can be performed with low
currents, in relation to the diameter of the wire and
is, therefore, especially suitable when working with
thin material or in cases where the welding heat
could create warping problems.
“ Spray arc ” welding requires higher arc voltages,
which also imply higher currents for an equal size
of wire in respect to “
short arc ” and is used with
medium/high sheet thicknesses.
For high currents with thick materials, it is preferred
with respect to “
short arc ”.
“Spray arc” welding is ideal for welding aluminium
or magnesium.
11/10/04 M33_WDC_GB