Electric arc furnaces offer several significant advantages over the more traditional types of blast furnaces. For new plants producing steel or in the other forms of smelting facilities these furnaces are more efficient, have a smaller footprint and creates less pollution, making them an extremely effective option.
The role of graphite rods is essential in the electric arc furnace or EAF. The rods have the job of transmitting or conducting the electricity that use to melt the metal. The metal can be recycled scrap, or it can be raw material, with electric arc furnaces used with both processing options.
The Basics
While electric arc furnaces can be either direct current or alternating current, most use alternating current. The alternating current passes through three columns of three graphite rods, with the rods consumed during the process.
When the EAF is operating on direct current, the graphite is arranged in one column with three rods in each column, at least in most traditionally designed furnaces in use in mini-mills.
The specific use or consumption of the graphite rods will vary based on the production cycles per day and other factors. As a general guideline, most furnaces using alternating current will consume one rod every 9 hours of operation. The consumption can be as low as every 7-8 hours or as high as 10 or more hours depending on the configuration, design, and efficiency of the system.
Why Graphite?
The choice of graphite is due in large part to the properties of these electrodes. Graphite provides excellent conductivity as well as to stand up to the very high heat levels in the furnace. The temperature in these EFAs can reach 5000 degrees Fahrenheit, which is more than many other types of materials used for industrial electrodes can tolerate.
The demand for graphite rodes will continue to increase as electric arc furnaces come online. Finding a dependable supplier for quality rods will be a critical factor for any manufacturer.