Carbon electrodes are used for airborne metal cutting. In addition, with their help, metals are welded, defects in metal sheets are removed, rivets are cut and other operations are performed. Carbon electrodes are made of electrotechnical amorphous coal.
Finished products have a sheet-black surface and are round rods, the cross section of which varies from 6 to 18 millimeters. The standard length of the rods is 25-70 centimeters.
To cut various types of metal, carbon electrodes are sharpened at different angles. So, for processing ferrous metals, one end of the rod is sharpened at an angle of about 65 degrees. To perform the welding of materials from non-ferrous metals, including for surfacing hard alloys, the electrode is sharpened at an angle of 30 degrees.
In the process of manufacturing the electrodes, technologies of dextrusion or molding and heat treatment of compositions are used. The products are based on coke or coal, and various binders (tar, tar, etc.) are added. In some cases, metal powder or shavings are included in the carbon electrode.
Products are used in various industries. They are used for cutting steel materials, making holes in alloyed, carbon and low alloy steels. In addition, they are used to cut copper, stainless or low-carbon steel, as well as other alloys used in the manufacture of metal structures, in mechanical engineering, shipbuilding, and the steel industry.
Carbon electrode welding has established itself as very high quality. It has many advantages over other common types of cutting. When performing welding using carbon electrodes, carbon, compressed air or electric current is used, which allows for excellent cutting of metal with removal. Welding work is carried out using compressed air or an electric arc, which not only melts the metal, but also removes itself with the help of an air stream.
This method of welding metal products has its own characteristics. For example, all work can be carried out only at constant current, and the arc length should be in the range of 6-15 millimeters.
In this case, the arc is ignited very simply and has sufficient stability. However, when reverse polarity arises, the arc will lose stability, and the electrode will burn and vaporize.
An arc formed by welding materials with carbon electrodes is highly sensitive to weather conditions (rain, magnetic blast, gas flows). In addition, when performing welding operations where carbon electrodes are used, a lower arc efficiency is obtained in comparison with the use of conventional metal rods. However, the value of coal rods cannot be underestimated. They make it possible to weld non-ferrous metal, thin-sheet materials, and carry out surfacing of electric pick-ups and hard alloys at a current strength within 1 kA.