TIG Welders and Welding Accessories

TIG welding uses a non-consumable tungsten electrode and a shielding gas, usually argon, to produce clean, precise welds. It is used on stainless steel, aluminium and thin steel, where the appearance of the joint and control of the weld pool matter. It is slower than other processes, but gives a cleaner result.

For aluminium, alternating current AC cleans the oxide layer during welding. For steel and stainless steel, direct current DC is enough. Models such as the Awelco TIG 320 AC/DC high-frequency inverter TIG welder or the Awelco TIG 200 AC/DC Pulse high-frequency inverter TIG welder cover both uses. Check the data sheet to confirm that the model is AC/DC.

Lift ignition starts the arc by touching the electrode to the workpiece and lifting it, without high-frequency spark. It is useful where high frequency could interfere with nearby electronic equipment. In the range this mode is available on MMA/TIG lift welders, such as the Awelco Mikrotig 200 MMA/TIG lift inverter welder.

The electrode diameter is chosen according to the welding current and the thickness of the workpiece. The electrode type changes with the material: for steel, electrodes with ceria or lanthana are usually used, while for aluminium pure or zirconiated electrodes are used. Always check the welder manufacturer's table.

The torch is chosen according to the maximum current it must withstand, which the welder states as its amperage rating. Cooling can be air or water, depending on the working power. Check that the connection is compatible with the welder and that the torch body is well insulated to avoid electric shocks.

You need a helmet with a filter suited to the welding current, welding gloves, natural-fibre clothing and safety shoes. Work in a ventilated area, because the process produces fumes and ultraviolet radiation. D.Lgs. 81/2008 (the Italian workplace safety law) requires the assessment of risks from artificial optical radiation for welders.

Clean the metal of oil, grease, rust and oxides with a dedicated brush and a suitable solvent. For stainless steel and aluminium, cleaning is critical, because oxide makes the weld dirty and porous. Clamp the workpiece or tack-weld it in place, and keep the shielding gas flowing until the weld has cooled.

The filler rod must have a composition equal to or compatible with that of the base metal. It is fed into the weld pool with the non-dominant hand, while the torch stays steady on the workpiece. For stainless steel and aluminium, specific rods exist, such as the Awelco TIG filler rods available in the range.