The Lorch IT 420 GW is an inverter TIG AC/DC power source with liquid cooling, for a 400 V supply. It gives 420 A at a 60% duty cycle and 330 A at a continuous 100% load. You set the alternating current frequency from 50 to 200 Hz.
What this machine is for
On alternating current you weld aluminium and its alloys, because the positive half wave tears the aluminium oxide layer off the pool. On direct current you take mild steel, acid resistant steels, copper, nickel and titanium, with a focused arc and a narrow heat affected zone.
The setting of the alternating current frequency from 50 to 200 Hz changes the shape of the arc. A low frequency widens the pool and gives a wider oxide cleaning zone, a high one narrows and stiffens the arc, so you hit the corner better. At 330 A the power source runs continuously, so you lay long circumferential runs without a break.
Features and equipment
- TIG AC/DC power source for 420 A at a 60% duty cycle and 330 A in continuous work at 100%.
- Welding modes: TIG AC, TIG DC and MMA on direct and on alternating current.
- Setting of the alternating current frequency from 50 to 200 Hz: you control the width and the stiffness of the arc.
- New TIG torch 8 m with liquid cooling: you walk around a large part without moving the power source.
Technical data
| Brand | Lorch |
|---|---|
| Model | IT 420 GW |
| Type | inverter TIG power source |
| Current type | AC/DC |
| Supply voltage | 400 V |
| Current at a 60% duty cycle | 420 A |
| Current at a 100% duty cycle | 330 A |
| Welding current given on the card | up to 500 A |
| Alternating current frequency | from 50 to 200 Hz |
| Cooling | liquid |
| Modes | TIG AC, TIG DC, MMA AC and DC |
| Process given on the card | pulse |
| TIG torch | new, 8 m, liquid cooled |
| Earth cable | new, 3 m |
What you get
- new TIG torch 8 m with liquid cooling
- new earth cable 3 m
What to watch out for
The supply is a 400 V mains and a three phase circuit sized for work at 420 A. The torch is 8 m and the earth cable 3 m, so keep the earth close to the part. The cooler needs a fluid with frost protection, check the level, the flow and the tightness of the quick couplings. On alternating current the tungsten electrode wears faster, keep a stock. For the MMA mode buy an electrode holder. The card gives no weight and no dimensions.
How we sell used machines
This unit was checked in our service workshop in Krotoszyn with measurements to PN-EN 60974-4 and a load test. The price includes the first year of the basic service package: an inspection with cleaning of the machine and a validation measurement. Further years can be added. We ship across the European Union, collection in person by appointment.








