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ELECTRODE WELDING AND GOUGING

Air-Carbon-Arc Gouging

The air-carbon-arc process utilizes the arc effect to melt the metal, which is subsequently blown away by a jet of compressed air. The method is therefore also useful for cutting stainless steel and other materials, which are difficult to cut by the oxyacetylene method. The air carbon arc process leaves a clean surface, free from slag, and further surface preparation is usually not necessary.

General uses include:

Forming welding grooves. Cutting and perforating. Removal of defective welds. Removing defects on cast iron and removing excess metal.

• Removing welding beads and burrs from plating.

• • • •

The equipment consists of a welding power source suitable for air carbon arc gouging, a special electrode holder with air ducts, copper coated carbon

graphite electrodes, a compressed air source (5-7 bar), cable and air hose.

The power source

In the Unitor range, model UWI-500 TP is a suitable power source for air-arc cutting having the special characteristic required for this process.

Two welding machines may also be connected together in parallel by connecting the negative terminal from both machines to ground at the worksite. The cables from the positive terminals are then lead to the worksite and connected at the electrode holder. For smaller jobs using small size carbon electrodes, model UWR-320 TP may be used as power source.

It is also possible to connect together 2 x UWI-320 TP and get 640 Amp for bigger size carbon electrodes.

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