Functional description
33
3rd step: Press torch button
The current reduces with the preselected downslope time to the value set for the
end crater current.
The welding current flows with the value set for the end crater.
4th step: Release torch button
The arc is extinguished.
The inert gas flows in accordance with the selected gas post-flow time.
Fig. 22: Procedure for 4-step welding
Special features:
re. 2nd step Pressing the torch button again during the upslope time causes the
arc to be extinguished and the inert gas flows in accordance with
the selected gas post-flow time.
re. 3rd step
The arc can be switched off during the downslope time. Releasing
the torch button before reaching the end crater current causes the
arc to be extinguished and the inert gas flows in accordance with
the selected gas post-flow time.
3.8.3
Welding with high frequency (HF)
The REHM TIG welding systems are equipped with HF ignition devices as
standard. In the "Electrode" setting, HF ignition is automatically switched off.
The HF ignition device makes contact-free ignition of the arc possible between
the electrode and the workpiece by pre-ionising the air gap during DC and DC
current welding, whereby tungsten inclusions and therefore welding errors are
prevented. In both cases the HF ignition device is switched off again after ignition
has taken place. The re-ignition of the arc that is described in chapter 3.7.1 takes
place without using the HF ignition device. This reduces the radiation of electrical
interference fields and even makes it possible to carry out AC current welding
without HF ignition, as is already known from DC current welding (see chapter
3.8.4).
With the high frequency setting the HF ignition device is ready for operation. In
order to ignite the arc, the electrode is held about 3-5 mm above the workpiece.
When the torch button is pressed, the gap is ionised by a high-voltage pulse and
the arc is created. The contactless ignition prevents tungsten inclusions in the
weld seam. During welding, the HF ignition device is automatically switched off
again after ignition has taken place.
Torch button 1
Gas valve
Welding current
t
t
t
Содержание INVERTIG.PRO digital 240 DC, 240 AC/DC
Страница 1: ...GB OPERATING INSTRUCTIONS TIG inert gas welding units INVERTIG PRO digital 240 450 DC AC DC...
Страница 7: ...Introduction 7 1 2 General description Figure 1 INVERTIG PRO digital...
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Страница 81: ...Components 81 Figure 53 Exploded view of an INVERTIG PRO digital 240 DC 450 AC DC left...
Страница 82: ...Components 82 Figure 54 Exploded view of an INVERTIG PRO digital 240 DC 450 AC DC right...
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