OK 21.03 is designed for gouging, cutting and piercing mild and alloyed steel, cast iron and non-ferrous metals, with the exception of pure copper, using standard welding equipment. The electrode can be used in a wide variety of applications, such as bevelling, the preparation of cracked areas before welding and the back-gouging of root runs.
The arc is struck with the electrode perpendicular to the workpiece, after which the electrode is pointed in the direction of travel at an angle of about 15-20°C and pushed forward. Gouging speed 100-150 cm/minute depending on the depth of the groove. Deep grooves can be made by repeated gouging. Welding can follow without further preparation, but, when gouging in stainless steel, a thin layer with increased carbon content is obtained and it should be removed by grinding. When using OK 21.03 indoors, it is necessary to have very good ventilation or fume extraction.