Rtech Tig200, Руководство по эксплуатации

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6
Use of DCEN
For a given diameter of tungsten electrode,
higher amperage can be used with straight
polarity. Straight polarity is used mainly for
welding:
Carbon steels
Stainless steels
Copper alloys
The increased amperage provides:
Deeper penetration
Increased welding speed
A narrower, deeper, weld bead.
DCEP
The DCEP (reverse polarity) are different from
the DCEN in following ways:
High heat is produced on the electrode rather
on the base metal.
The heat melts the tungsten electrode tip.
The base metal remains relatively cool
compared to sing straight polarity.
Relatively shallow penetration is obtained.
An electrode whose diameter is too large will
reduce visibility and increase arc instability.
Use of DCEP
Intense heat means a larger diameter of
electrode must be used with DCEP.
Maximum welding amperage should be
relatively low (approximately six times lower
than with DCEN).
Alternating Current with High-Frequency
Welding with alternating current
Welding with alternating current combines both
direct-current characteristics:
In the positive phase, cleaning action occurs in
the weld puddle.
During the negative phase, heat is
concentrated in the weld puddle.
The above causes increased penetration.