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ELECTRODE WELDING AND GOUGING

The electrode holder

A special jaw-type electrode holder is used for air carbon arc gouging. The jaws are fitted with nozzles, which direct jets of compressed air parallel with the electrode to the molten pool. The holder is also equipped with a cut-off valve for compressed air. Compressed air supply 400–900 l/min at a pressure of approx. 5–7 bar. The holder will accept round and flat electrodes. It is supplied complete with integrated compressed air hose/welding cable, cable connectors and a quick connector 30UPH for compressed air.

General rules for air-carbon-arc gouging • Check that all screw connections

are properly tightened to minimize any loss of effect.

• Clean the electrode jaws

occasionally with a steel brush to ensure good contact. Blow out the air line before connecting to the holder to remove any condensation.

• Check the current and remember

that the high arc voltage will usually require a higher than usual setting on the amperage scale. If amperage is too low, gouging will be unsatisfactory.

• Check that the air supply is

switched on and the air-valve on the holder is in the open position before striking the arc.

• Keep the arc short, but avoid

touching the workpiece with the electrode once gouging has commenced.

• When gouging in the overhead

position, make sure that molten metal does not fall directly on to the electrode holder.

• When the equipment is in regular

use, dismantle and clean the valve at least once a month and make sure that the air passage is not obstructed. Lubricate the 0-rings with special valve grease.

• Set the air pressure at 5 to 7 bar. • Check connections for correct

polarity.

• Fit the electrode in the holder so

4.01

that it protrudes approx. 150 mm from the holder.

• When the electrode is moved from

right to left, the air outlets in the electrode jaws must be positioned on the right side of the electrode so that the main stream of the compressed air jet is lead beneath the electrode.

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Electrode holder for air carbon arc gouging