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INE S.p.A.
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This method is only used in flat position of butt and fillet
welds on material of 4 mm and above, where a higher
deposition speed is required. The greater the arc length
(corresponding to a greater voltage V), with equal
current A, the wider and flatter the weld bead. This
means that by increasing the voltage the “deposition
cone” of the weld material widens.
At this point, special mention is deserved by the
pulsed-arc MIG/MAG welding procedure, which is
characterised by a non-constant, high-value pulse
current flow. Between pulses the current value is at a
minimum so as to keep the arc on without melting the
material. Thus the average welding current value can
be reduced even if welding with the spray-arc method.
So the advantages of this method (high-quality welds
thanks to the spraying of the molten metal, and the
variable weld bead width) can be achieved even at low
current values, typical of the welding of thin materials
and of welding positions other than butt welding.
To complete the topic, also the concept of synergy
(synchronisation) is to be mentioned. In a sync welding
machine, the couple welding voltage / welding current
is not set by the operator, who is only given the choice
of the arc power. This way time is saved since the
welding parameters are automatically adjusted and this
optimal functioning guarantees an almost spatter-free
welding.
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Содержание KMP3200
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