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TIG WELDING

Welding Techniques

Before welding starts, check that the torch is connected to the negative (-) polarity of a DC constant current power source, and that sufficient gas is available from the gas supply. Open the argon cylinder valve and the torch valve. If necessary, purge the gas system before setting correct gas flow on the regulator.

Striking the Arc

Check that the electrode is properly pointed and protrudes 3-6mm from the nozzle. Do not touch the electrode unless the DIX connector is disconnected. If current remote control is available, adjust to low or minimum current.

Ensure that the gas valve is fully open, (3/4 turn from closed). Place the gas nozzle in a tilted angle on the ignition location so that there is a gap of 2-3 mm between the tungsten electrode tip and the workpiece. Gradually tilt up the welding torch until the tungsten electrode tip touches the workpiece. This will trigger the lift arc function. Raise the torch and lift it into the normal position- the arc ignites and increase in intensity to the set amperage. Note: To be absolutely certain that contamination is avoided the arc may be started on a copper plate placed on the workpiece, and then moved to the beginning of the bead.

Connect the equipment and purge the gas system. Check electrode and electrode stick-out.

The lift arc function

2–3 mm

Place nozzle on location.

Gradualy tilt up.

4.02

Adjust welding current to correct setting and hold the arc steady until a molten pool is formed.

Raise the torch

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