Abstract
Graphitized electrodes (GE) are a consumable material in electric arc melting. Their consumption in the steel cost structure in some cases reaches 30%, so reducing it is an urgent task. It has been proven that the main consumption items of GE are the oxidation of its side surface under the influence of temperature and thermo mechanical destruction and wear, i.e. the consumption of electrode material significantly depends on its thermal state. There are different ways to solve this problem. The most promising method in terms of manufacturing costs and technology of use for domestic metallurgical and foundry enterprises is the method of evaporative cooling (EC) of the side surface of the GE. The purpose of the work is to review various designs and determine practical recommendations for the application and manufacture of evaporative cooling systems for GE. A patent search for existing EC systems was conducted. Based on a literature review, various options for their designs are considered. For the first time, experimental work was carried out on an ore-smelting furnace with a capacity of 100 tons. It was established that the use of artificial insulation leads to a decrease in temperature and oxidation of the side surface of the GE. Electrode consumption is reduced by an average of 15%. The efficiency of the EC depends on the design of the cooling ring and the technological parameters of the sys-tem, such as water flow and the time it is turned on. Recommendations are given for the manufacture and use of evaporative cooling systems. As a result of studying various sources, it was determined that in the Russian Federation this technology is used only on foreign-made arc furnaces (Danieli, Fuchs) with a capacity of more than 80 tons, because there it is supplied with the oven. There is not a single enterprise in Russia that develops and implements such systems. For enterprises that have arc furnaces of different capacities, the rational use of artificial electrodes will reduce the specific costs of steel production, and for enterprises producing these furnaces, increase the level of equipment, automation and, ultimately, sales.
Keywords:
arc furnace, EAF, graphite electrode, evaporative cooling, spray cooling, graphite electrode consumption, thermal state modeling, spray ring.