Jasic EVO 2.0 EM-160C, Руководство оператора

Страница: 65 / 82

65
GUIDE TO TIG WELDING
Before starting any welding activity ensure that you have suitable eye protection and
protective clothing. Also take the necessary steps to protect any persons within the welding
area.
TIG welding consumables
The consumables of the TIG welding process are filler wires and shield gas.
Filler wires
Filler wires come in many different material types
and usually as cut lengths, unless some automated
feeding is required where it will be in reel form.
Filler wire is generally fed in by hand.
Always consult the manufacturer ’ s data and
welding requirements.
Gases
Shielding gas is required when welding to keep the weld pool free of oxygen. Whether you are welding
mild steel or stainless steel the most commonly used shielding gas used in TIG welding is argon, for more
specialised applications an argon helium mix or pure helium may be used.
TIG welding - arc starting
The TIG process can use both non contact and contact methods to provide arc starting. Depending on the
Jasic model, the options are indicated on a selector switch on the front control panel of the power source.
The most common method of arc starting is
‘ HF ’ start. This term is often used for a variety of starting
methods and covers many different types of start.
Arc starting - scratch start
This system is where the electrode is scratched along the work piece like striking a match. This is a basic
way of turning any DC stick welder into a TIG welder without much work.
It is not considered suitable for high integrity welding due to the fact that the tungsten can be melted on
the work piece thereby contaminating the weld.
The main challenge with scratch start TIG welding is keeping your electrode clean. While a quick strike
with the electrode on the metal is essential and then not lifting it more than 3mm away to create the arc
will help, you also need to ensure your metal is completely clean.
Filler Wire Diameter DC Current Range (Amps)
1.0mm 20 - 90
2.4mm 65 - 115
3.2mm 100 - 165
4.8mm 200 - 350
Filler Wire Selection Guide