In 1890, H. Moissan started to use electric furnace to make steel in France. In 1896, in America, E. G. Acheson invented artificial graphite resistance furnace system method and established the first artificial graphite manufacturing company in 1900, which began the industrial production of artificial graphite. At that time, the production of electrode mainly used in electrochemical industry to produce caustic soda. In 1900, P.Héroult used electric arc furnace to make steel in industry successfully in France. In 1914, the United States produced a diameter of 355.6 mm (14 inches) of artificial graphite electrode .
At that time, it is mainly use carbon electrodes produced by anthracite coal and the natural graphite as raw material to produce natural graphite electrode. To the 1960s, carbon and graphite electrodes have been widely used in electric arc furnace steelmaking. In 1964, in America, W. E. Schwabe proposed using ultra high power (UHP) graphite electrode in electric furnace steelmaking. American Great Lakes Charcoal company first developed a needle coke. The graphite products ,which are made by needle coke, are heatproof , high impact-resistance, good oxidation resistance and high current density. UHP graphite electrode was developed in 1966 and began to practical application. With the successful development of high power and ultra-high power electrode, the electrode consumption of per ton steel also from ordinary power electrode 6 ~ 8 kg down to 4 ~ 6 kg of high power electrode and about 2. 5 kg of UHP electrodes. In the 1980 s, the development of large UHP direct current electric arc furnace can be further reduced to 1. 0 kg below with single UHP graphite electrodes.With the gradual increase of the capacity of electric arc furnaces, transformer input power of per ton capacity is also increasing. New furnaces almost were ultra high power electric furnace for 80 ~ 150 t, the input power is also increased to 800 kW/t, even 1 000 ~ 1 200 kW/t. Because the power increases, the current density of the electrode is denser, so it requires better conductivity, higher tensile and bending resistance and lower thermal expansion coefficient and the porosity. Along with the enlargement of the electric furnace, electrode diameter also increases, which now has developed to a diameter of 750 ~ 800 mm. At present, graphite electrode production capacity is 1.5 million ton in the world and actual output is about 1.2 million t. The general form of capacity is: the United States, 200000 t; Germany, 210000 t; China, 450000 t; Japan, 160000 t; India, 60000 t; Others, 23 ~ 25 t.
Carbon electrode use anthracite coal and metallurgical coke as raw material and without graphitization treatment. Its resistivity is stronger than graphite electrode, the current density is lower, but it has the features of high temperature resistance, corrosion resistance, low prices, so still used in ore heat furnace of industrial silicon, yellow phosphorus or corundum. There are still some enterprises in the production at home and abroad.
The progress of the steelmaking technologies leaded to graphite electrode consumption greatly reduced. At the same time, with the limits of China’s energy policy and resource constraints and to meet the strict requirements of environmental protection, infrastructure investment and running cost of carbon enterprises in developed countries is much higher than in the developing world, its price competitiveness is relatively low, so the developed countries’ graphite electrode production decreased year by year. Multinational companies of the main bulk carbon materials are cutting production or closing the excess production capacity. The famous bulk carbon materials companies in foreign countries experienced mergers, acquisitions, restructuring, expansion for decades, the production ability of graphite electrode are above 150000 t/year, which form large leading companies to produce the bulk carbon materials in the world. The factory strictly implemented specialization production: 1 ~ 2 production line specifically for the production of connectors, the rest specializing in the production of a 1 ~ 2 specifications varieties of UHP electrodes, which is not easily replaced. Each factory production capacity is about 1 ~ 40000 t/year. In recent years, the graphite electrode’s international market is very good and the market prices are also rising. The international market at the beginning of 2003 was about 2000 dollars/ton, at present, it has doubled breaking the 4000 dollars/ ton. Take the west of carbon group (SGL group) for example, since June 4, 2004, the new price after adjusting is: the sales price of under 600 mm diameter is 4100 $ / ton; the sale price of above 700 mm diameter is 4450 $ / ton.Chinese carbon materials industry after more than 50 years’ development, now has hundreds of different-sized enterprise (Graphite electrode, aluminum carbon product). But among them, only 40 companies have a certain production scale and a complete set of processing equipment. There are more than 20 companies, who has a considerable scale to produce graphite electrode.
HP Graphite (Beijing) Co. Ltd is one of Graphite Graphite companies, which has more than 15 years experience in the graphite industry. If you have any question about graphite electrodes or graphite products you can contact us.