Air carbon arc gouging is the fastest way to remove defective welds, back-gouge joints and cut out old steel in shipyards and heavy fabrication. Here is how to set it up properly.
How it works
An arc between a carbon electrode and the workpiece melts the metal, and a jet of compressed air blows the molten metal away. The result is a clean groove ready for welding.
Choosing a gouging torch
Match the torch to the carbon size and current you use. The K3 gouging torch (600A) suits general repair and back-gouging. The K4000 gouging torch (1000A) handles larger carbons and heavy production work.
Air supply
Gouging needs a steady supply of clean, dry compressed air. Weak or wet air leaves slag in the groove and can cause carbon pick-up. Use a portable air dryer to remove moisture, and check hose fittings such as air hose tails for leaks.
Power and connections
Gouging draws high current, so use a welding machine with enough output and heavy cables with sound connections. A firm G-type earth clamp close to the work and a tight heavy-duty cable connector prevent overheating.
Good technique
- Turn the air on before striking the arc.
- Keep the air jet behind the carbon, pointing in the direction of travel.
- Use a steady travel speed; the angle and speed control groove depth.
- Grind the groove clean before welding.
Safety
- Gouging is very loud: wear hearing protection.
- Molten metal sprays a long way: clear combustibles and protect people nearby.
- Wear a welding headshield, welding gloves, arm covers and leg covers.
- Ensure good ventilation or fume extraction.
Gouging equipment in Singapore
Fong Yung Industries LLP stocks gouging torches, spare parts and cables in the EVO-Arc range. Browse the range or request a quote.