Graphite electrode for electric arc furnace
The graphite electrode of the electric arc furnace refers to the conductor material that the electric arc furnace releases electric energy in the form of an electric arc to heat and melt the charge. It mainly uses petroleum coke and needle coke as raw materials, and coal tar pitch is used as a binder. It is calcined, batched, kneaded, and pressed. , Roasting, graphitization, and machining.
According to its quality indicators, it can be divided into regular power graphite electrodes, high power graphite electrodes, and ultra-high power graphite electrodes.
The steel-making electric arc furnace uses graphite electrodes as conductive materials and transfers heat energy to the charge through arc discharge to melt the charge. An ordinary electric arc furnace has three electrodes, each of which consists of 3 to 4 electrodes connected together with a tapered joint. The electrode is clamped by the gripper at the end of the cantilever. The cantilever and the soft bus connected to the power supply rise and fall together.
The heat during smelting is generated by the arc discharge between the electrode and the metal charge. The arc formed at its tip converts electrical energy into heat for smelting needs. Since most of it is in the furnace, it bears the radiant heat of the high-temperature furnace gas, the surface of the molten pool, the furnace wall, and the arc column at the electrode tip.
The furnace gas washes the surface of the electrode and heats the electrode by convection heating. This heat transfer effect is strengthened with the increase of furnace gas and material temperature and furnace gas volume.
It is precisely because of the harsh working environment that compared with other conductive materials, graphite materials have some excellent or irreplaceable characteristics under high-temperature conditions.
Graphite electrodes can be used at relatively high temperatures. The sublimation temperature is 3650℃. It is a high-temperature conductive material that can withstand high temperatures. In actual use, there is no other material that can replace it.
Graphite’s strength increases with temperature at high temperatures; compared with other metals, graphite has the lowest coefficient of thermal expansion.