minimum consumption of graphite electrode
The purpose and function of minimum consumption of graphite electrode
The purpose and function of the minimum consumption of graphite electrode: ①Improve the electrical and thermal conductivity of carbon materials (resistivity is reduced by 4-5 times, and thermal conductivity is increased by about 10 times); ②Improve the thermal vibration resistance and chemical stability of carbon materials ( The coefficient of linear expansion is reduced by 50-80%); ③ the carbon material has lubricity and anti-wear properties; ④ the impurities are discharged and the purity of the carbon material is improved (the ash content of the product is reduced from 0.5-0.8% to about 0.3%).
Realization of the graphitization process: The graphitization of carbon materials is carried out at a high temperature of ℃, so the industry can only be realized by electric heating, that is, the electric current directly passes through the heated calcination product, and the calcination product loaded into the furnace is passed through A conductor that generates a high temperature by an electric current is an object that is heated to a high temperature. Currently widely used furnace types include Acheson graphitization furnace and internal heat series (LWG) furnace. The former has large output, large temperature difference and high power consumption, while the latter has short heating time, low power consumption, uniform resistivity, but it is not easy to install joints. The graphitization process is controlled by measuring the temperature to determine the electric power curve suitable for the heating situation. The power-on time is 50-80 hours for the Acheson furnace and 9-15 hours for the LWG furnace. Graphitization consumes a lot of electricity, generally KWh, and the process cost accounts for about 20-35% of the entire production cost. Inspection of graphitized products: appearance knocking and resistivity testing. Machining: The purpose of carbon graphite material machining is to rely on cutting. Processed to reach the required size, shape, precision, etc., and made into the body and joints that meet the minimum consumption of graphite electrode.
The minimum consumption of graphite electrode processing is divided into two independent processing processes, the minimum consumption of graphite electrode body and the joint. The body processing includes boring and rough flat end face, turning outer circle and fine flat end face, and thread milling 3 processes. The processing of conical joints can be divided into 6 processes: cutting, flat end face, turning taper surface, milling thread, drilling and anchoring And slotting. Minimum consumption of graphite electrode joint connection mode: conical joint connection (one inch three buttons and one inch four buttons), cylindrical joint connection, concave-convex connection (male and female button connection) processing accuracy control: thread taper deviation, thread pitch, Joint (hole) large diameter deviation, joint hole coaxiality, joint hole verticality, minimum consumption of graphite electrode end surface flatness, joint four-point deviation, etc. Use special ring gauges and board gauges to check. Inspection of the finished product minimum consumption of graphite electrode: accuracy, weight, length, diameter, volume density, resistivity, pre-installation accuracy, etc.