Graphite electrodes are consumables used in electric arc furnace steelmaking. Each ton of steel consumes 2 kilograms of graphite electrodes.
Graphite electrode details
Graphite electrode, mainly petroleum coke, needle coke as raw material, coal pitch as binder, calcination, ingredients, kneading, molding, baking and graphitization, machining and made, which is released in electric arc furnace in the form of arc conductor of electricity to heat melting furnace charge, according to the high and low quality index, can be divided into ordinary power, high power and ultra-high power graphite electrode.
Type of graphite electrode:
Graphite electrode blueprint
Graphite electrode is composed of body and nipple.
Graphite electrode abbreviation
Graphite electrode abbreviation G.E, or RP, HP, UHP.
Graphite electrode baking process
Two types of baking furnaces are in use:
● Car bottom furnace
The extruded rods are placed in cylindrical stainless steel canisters (saggers). To avoid the deformation of the electrodes during the heating process, the saggers are also filled with a protecting covering of sand. The saggers are loaded on railcar platforms (car bottoms) and rolled into natural gas - fired kilns.
The saggers are loaded on railcar platforms (car bottoms) and rolled into natural gas - fired kilns.
● Ring furnace
The electrodes are placed in a stone covert cavity in the bottom of the production hall. This cavity is part of a ring system of more than 10 chambers. The chambers are connected together with a hot air circulation system to save energy. The voids between the electrodes are also filled with sand to avoid deformation. During the baking process, where the pitch is carbonized, the temperature has to be controlled carefully because at the temperatures up to 800°C a rapid gas build up can cause cracking of the electrode.
Graphite electrode binder
Coal tar is one of the main products of coal tar deep processing. It is a mixture of various hydrocarbons. The composition is complex and it is black high viscosity semi-solid or solid at room temperature. According to the softening point, coal tar can be divided into low temperature, medium temperature and high temperature coal tar pitch(binder pitch).
Coal tar pitch is used as a binder and an impregnating agent in the production of graphite electrodes, and a medium-temperature or medium-temperature modified coal tar pitch having a moderate softening point and a high coking value is generally used.
Graphite electrode applications
Graphite electrodes are widely used for production of alloy steels, metal and other nonmetallic materials, etc. Type of electric furnace: DC electric arc furnace & AC electric arc furnace & Submerged arc furnace & Ladle furnace.
Graphite electrode uses
Graphite electrode activity
Graphite electrodes only conduct electricity and do not participate in reactions, They are inert electrodes.