Tig Welding Process - Praxair AC/DC 322 PULSE Manual De Instrucciones

MICROTIG AC/DC 322/402 PULSE
7.2 -TIG WELDING MODE
- Make the necessary connections to mains and earth as described in "Installation".
- Connect earth cable to positive plug by turning it firmly to right to assure a perfect electric contact.
- Connect TIG torch power cable to negative plug by turning it to right to assure a perfect electric contact.
- Connect gas tube to gas connection.
- Connect TIG torch control cable to the front panel connector.
- Connect input gas tube to gas inlet on machine rear panel and to the flowmeter on gas bottle. Check the content of
gas bottle, and replace it, if necessary.
- Adjust gas flow 6 l/min and 12 l/min according to the value of the current.
- Apply a tungsten electrode on TIG torch. The electrode must be sharpening according the welding method: TIG DC
(tip sharpen).
- Turn the main switch on rear panel to ON position.
- The Power ON indicator lights, indicating that machine is under voltage.
- Select TIG HF* (TIG welding with high frequency ignition) or LIFTIG** (TIG welding with contact ignition).
* TIG HF:
1-pre-gas 2-HF ignition 3-welding 4-post-gas
5-stop
** LIFTIG:
1-open gas 2-contact 3- arc ignition 4-welding 5-stop 6-close gas
LIFTIG ignition (by contact) should be used when the high frequency radiations could disturb the functioning of
electronic devices near the welding zone (computers, pace-makers, medical tools, etc).
- Select GAS (gas-cooled torch) or WATER (water-cooled torch) in the cooling selector.
- Select 2T* (2 times) / 4T** (4 times) mode.
* 2T - The gas starts to flow according to the PREGAS adjusted time when the torch trigger is pressed, and the arc is
established. The current rises according to the UPSLOPE time and to the IStart current value to the main current
adjusted value Ip. When the torch trigger is released, the current decreases according to the IFinal current value. After
the adjusted DOWNSLOPE time, the arc extinguishes, and the POST GAS time begins.
** 4T - The gas starts to flow according to the PREGAS adjusted time when the torch trigger is pressed. When the
torch trigger is released, the arc automatically establishes. The current rises according to the UPSLOPE time and to
the IStart current value to the main current adjusted value Ip. When the torch trigger is press and release, the current
decreases according to the IFinal current value. After the adjusted DOWNSLOPE time, the arc extinguishes, and the
POST GAS time begins.
12