Thermal gouging that uses an oxygen cutting process variation to form a bevel or groove. Oxygen gouging of steel plate is usually limited to steel plate thicknesses up to 25 mm (1 in.). The OFC process is frequently used on the underside of a welded joint to remove defects that are in the original root pass, or to remove defective weld joints or cracks when repairing previously fabricated metal.
The gouging process usually requires a special gouging tip with extra-heavy preheat capacity and a central oxygen orifice that causes a high level of turbulence in the oxygen stream. This turbulence causes a wide flow of oxygen that can be controlled by the operator to achieve the desired width and depth of gouge. Other factors used to determine the shape of the gouge are speed, tip angle, oxygen pressure, amount of preheat, and tip size. One of the significant advantages of oxygen gouging is that no additional equipment other than that already used in the oxyfuel cutting process is required. See OXYFUEL GAS CUTTING.