Gouging Nozzles

Gouging Nozzles

Carbon arc gouging is a process for removing metal from a workpiece — used for back-gouging weld roots, removing defective weld passes, cutting through thick sections, and preparing surfaces for rewelding. A carbon electrode is held in a gouging torch; an arc is struck between the electrode and the base metal, melting a localised area; a high-velocity air jet from nozzles adjacent to the electrode blows the molten metal clear of the cavity. The result is a clean, U-shaped groove that exposes sound metal below the defective layer. AIMS Industrial supplies gouging nozzles, electrodes, and related consumables for carbon arc gouging operations.

Gouging Nozzle and Torch Operation

The gouging torch holds the carbon electrode and directs the air jets. Nozzles on either side of the electrode holder direct the air stream along the arc, behind the molten pool, blowing it clear of the work. Nozzle angle and air jet position are critical — the air must arrive just behind the arc to clear the melt pool effectively. Nozzles wear and must be replaced when the air jet direction is compromised by erosion. A poorly directed air jet leaves slag in the groove and reduces gouging efficiency significantly.

Carbon Electrodes

Carbon gouging electrodes are round graphite-copper-coated rods. The copper coating improves electrical conductivity and reduces electrode consumption. Electrode diameter determines the width of the gouge — larger diameter electrodes produce wider, deeper grooves at higher current settings. Common diameters run from 5mm (for light gouging at 150–200A) to 16mm (for heavy gouging at 500–1000A) and above. DC electrode positive (DCEP) is the standard polarity for carbon arc gouging, providing higher arc temperature and more efficient metal removal than AC or DCEN.

Safety Requirements

Carbon arc gouging produces intense UV radiation, significant noise (the arc and air blast are loud), metal fume, and molten metal spatter over a large area. Full welding PPE is required — leather gloves, welding helmet with appropriate shade (shade 10–12 is typical), leather apron, and hearing protection. The work area requires exclusion of flammable materials and personnel not directly involved. For gouging nozzle and electrode supply, contact our team.

Gouging Technique for Best Results

Correct torch angle and travel speed are the main variables affecting gouge quality. Hold the torch at approximately 35–45 degrees to the workpiece surface for standard carbon arc gouging — a shallower angle produces a wider, flatter groove while a steeper angle cuts deeper with a narrower profile. Travel speed should be consistent; moving too slowly allows the arc to penetrate deeper than intended and can cause carbon contamination of the base metal. Use clean, dry compressed air at the recommended pressure for the electrode diameter being used. After gouging, inspect the groove and grind away any carbon deposits before welding.