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 (1) Control the interval time and length of the lower electrodes. If the electrode is soft, you should take the approach of frequent release, less release or late release. If it is too dry, allow more release. (2) When the electrode is discharged, the load decreases and increases. If the electrode is soft, a large amount of current will pass along the surface of the electrode, and the electrode shell may be burnt due to current impact. Therefore, under normal circumstances, the load must be reduced when the electrode is discharged, and the full load shall not be restored all at once after the electrode is discharged.

 Anthracite is the main part of the electrode paste. When the electrode is fired, it becomes the skeleton of the electrode, which is very similar to the role played by the pebbles in reinforced concrete. The use of anthracite is not only because of its low price, but more importantly, it can improve the quality of electrode paste. Anthracite is a dense, black grease mineral with metallic luster. The difference between anthracite and other mineral coals is: high carbon content, high mechanical strength, and low volatile content. Anthracite contains a small amount of water, which is evenly distributed in the carbon, and its ash is basically in thin layers or spots. Minerals. The ash content of anthracite used in the manufacture of electrode paste is generally not higher than 10%. Therefore, after entering the factory, it is sorted and its ash content is generally fixed below 8%. When the coal is in the form of flakes and long blocks, it is heated and calcined , Easily burst into pieces d

 The main component of the raw material of the electrode paste is carbon. Carbon has the following properties, so it can be called the main raw material for making electrode paste. 1. Withstand the high temperature necessary for industrial technology; 2. The oxide is a gas; 3. Good electrical conductivity; 4. Difficult to reflect with many chemical substances. There are two types of raw materials used in the manufacture of electrode paste: 1. Solid carbon raw materials (anthracite, petroleum coke, artificial graphite, etc.). 2. Binder (asphalt and coal tar). It should be pointed out here that the raw material used as a binder should be able to turn into a strong coke after roasting, which will cause coking to form a self-burning motor as a whole.

 Coke is one of the most important raw materials for making electrode paste, especially graphitized electrodes. The most valuable coke is low-ash coke (sometimes called ash-free coke), and its ash content does not exceed 1%. These cokes include petroleum coke and pitch coke. The first type is coke obtained by coking petroleum residue, and the second type is coke produced by processing coal pitch in a chemical coking industrial furnace. The solid carbon-containing product obtained by high-temperature treatment of petroleum residue is called petroleum coke. Due to the different raw materials and production methods, the content of these products is also different. At present, there are two types of petroleum coke with different properties, one is kettle-type petroleum coke, and the other is delayed coking petroleum coke. The former contains 3 to 7% of volatile matter, and the latter contains 10 to 18% of volatile matter. The residue obtained by coking coal tar pitch in the same coke oven

 As the raw material of the binder, when the electrode paste is self-baked and sintered, the remaining coking residue can increase the strength of the electrode paste and make it uniform. The best binders are coal pitch and coal tar. 1. Coal tar Coal tar is a group of fractions with a lower temperature than coal tar pitch. It is a viscous liquid with a color ranging from dark brown to black and a relative density of 1.05~1.25. The quality of tar mainly depends on the temperature conditions of coking and the structure of the furnace. In the furnace of the same structure, the temperature is the same, and the tar with the same composition and physical properties can be obtained when coking coal with different compositions. 2. Coal pitch Asphalt is a black shiny solid substance with a relative density of 1.245 to 1.299. When the distillation temperature is 360. The residue left after the other components in the tar are extracted at the above is the pitch. According to the size of the softe

 The quality of the electrode paste is very important to the normal operation of the mine thermoelectric furnace. Therefore, although the production process of the electrode paste is relatively simple, it must not be taken lightly. If the electrode paste uses unqualified raw materials, or the mixing is not uniform, or the amount of binder does not meet the requirements, the produced electrode paste will experience soft and hard breaks during use, which will not only cause malfunction of the mine thermoelectric furnace , It may also cause more serious consequences and lead to the suspension of production. Soft break means that the electrode paste is burnt when it is lowered near the furnace surface when it is not fired, and the unsintered electrode paste flows out; hard break means that the electrode paste has been fired, but due to the electrode paste. There is a crack on the column or the mechanical strength of the motor is low, which causes the electrode to break.

 In the compression test, when the density reaches or exceeds 90% of the maximum achievable density, the binder component in the electrode paste has sufficient fluidity to fill the electrode cylinder. After ensuring the compressibility, it is important to study the viscosity of the electrode paste. This is to evaluate the segregation performance of the electrode paste, because the greater the viscosity of the electrode paste, the less likely it will be segregation. Generally, viscosity is also related to bitumen content. The pitch in the electrode paste must provide sufficient plasticity to facilitate the compression of the electrode paste, but the pitch content must be as small as possible to avoid segregation. At each temperature point, the penetration of the cone in the electrode paste is expressed as a percentage of displacement related to the total height of the cone. If the penetration value of the electrode paste is greater than 70%, it means that the viscosity of the electrode

 The raw material for making electrode paste is composed of solid carbon material and binding material. The quality of the electrode paste is related to the material formula and process. Solid materials include anthracite, metallurgical coke, petroleum coke and pitch coke, and graphite electrode scraps. Anthracite is dense, high in carbon content, low in volatile matter and low in price. Adding anthracite can improve the electrical conductivity and thermal conductivity of the electrode. The binding materials are pitch and tar. Tar is added to adjust the softening point. The binder in the electrode paste decomposes and removes volatiles during the sintering process, and the residual carbon is transformed into a strong coke net, which has a coking effect, making the electrode a hard whole.