博文

目前显示的是 十月, 2021的博文

Introduction and selection of burner bricks

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  Burner brick is a kind of refractory brick used with the burner of high temperature kiln, such as blast furnace gas burner, special burner for lime furnace kiln, shaft furnace burner, regenerative heating furnace burner, etc. The shapes are different, and the burner bricks used do not have fixed specifications and sizes, and they often need to be customized in refractory manufacturers. The use of high-aluminum steel fiber castables can meet the working conditions of most burners. The function of the burner brick is: 1.The fuel is heated to the ignition temperature in the burner brick, so that it is easy to ignite and burn quickly. 2.Keep a certain high temperature in the burner brick to stabilize the combustion process and avoid pulsation or fuel interruption. 3.The flame shape of the organization meets the requirements of the heating process. 4.To further mix the fuel and air. Therefore, the burner brick is an indispensable high-temperature resistant material for the

Refractory for working layer of converter

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  The working layer of the converter is in direct contact with high-temperature molten steel and slag. It is subject to the chemical erosion of high-temperature molten slag, the scouring of molten steel, slag and furnace gas, and the mechanical impact when adding scrap steel. The working environment is very bad. In the blowing process, due to the different working conditions of each part, the corrosion condition and amount of lining are also different. In view of this situation, depending on the damage degree of lining bricks, build refractory bricks of different materials or different levels of the same material, which is the so-called comprehensive furnace building. High grade magnesia carbon bricks shall be built at the parts that are easy to be damaged or difficult to repair; Parts with light damage and easy repair, Medium or low grade magnesia carbon bricks can be built. After the slag splashing technology is adopted, the wettability between the lining brick and the

Advantages of using waste refractory bricks to make sintered clay bricks

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  Using waste refractory fire bricks to make sintered clay bricks has the following advantages: First, waste refractory bricks can be used as raw materials for making clay bricks , so that they can be reused as resources and help protect the environment; The second is that the waste refractory bricks contain silica, alumina, and iron oxide components, which are used as aggregates and clay to be mixed into a billet, dried and roasted, which can significantly improve the compressive strength of the brick and obtain the required water absorption; Third, the roasting does not need to change the roasting process, the energy consumption and carbon dioxide emissions will not increase, and it will not have an adverse effect on the production cost and the environment. Due to the increased roasting temperature, the product deformation is less and the qualification rate is high; Fourth, as long as the idea is changed to achieve the same compressive strength as ordinary sinte

Improvement measures for corrosion of tundish stopper

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  1. Strictly control the slag from the big bag The main sources of slag components in the casting area of the tundish are ladle refining slag, tundish covering agent and molten steel inclusions floating up into the slag layer. Among them, the low silicon aluminum killed steel refining slag , which is more severely corroded by the stopper rod, is a high basicity refining slag system, and the CaO content in the slag is controlled at 55%-65%. The large ladle slag of each furnace will form a refined slag enrichment in the injection point area of the tundish. During the subcontracting process and when the pouring steel stream impacts the slag surface of the injection point area, it will cause the refined slag to enter the casting area and cause erosion of the stopper. Therefore, it is necessary to strictly control the slagging of the big ladle, and use the automatic control of the slag detection to avoid a large amount of slagging at the end of pouring. At the same time, th

Production process and damage mechanism of tundish sizing nozzle

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  The zirconium sizing nozzle is used as the key refractory material for billet continuous casting, which controls the flow of molten steel, determines the drawing speed of the billet in continuous casting, and is a necessary condition to ensure the normal operation of continuous casting. In addition to cracking, blockage and falling off of the sizing nozzle, it is also required that the diameter expansion speed should not be too fast to meet the requirements of long-term casting. Damage to the sizing nozzle . The damage process of the oxidized sizing nozzle is a complex physical and chemical effect of its interaction with steel slag and molten steel at high temperatures. The specific damage mechanism is divided into two categories: (1) Physical damage: During the use of the sizing nozzle, due to the large temperature difference between before and after pouring steel (the pouring temperature of the steel is 1540C, uneven heating, a huge thermal stress is generated insi

Main tasks of the electric furnace during the oxidation period and reduction period

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  Electric furnace oxidation period The oxidation period of electric furnace is the main process of oxidation smelting, which can remove phosphorus, gas and inclusions in steel. When the scrap steel material is completely melted and reaches the oxidation temperature, more than 70% to 80% of phosphorus is removed and enters the oxidation period. In order to ensure the progress of the metallurgical reaction, the oxidation starting temperature is 50-80°C higher than the melting point of the molten steel. The main tasks during the oxidation period of the electric furnace: Continue dephosphorization to the requirement-dephosphorization; Decarburization to the lower limit of specification-decarburization; Get rid of gas, get rid of inclusions-go two; Increase the temperature of molten steel-heating up. Electric furnace reduction period In the traditional electric furnace smelting process, the existence of the reduction period shows the characteristics of electric

Tasks and operations during the melting period of the electric furnace

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  Electric furnace steelmaking uses electric energy as the main heat source and uses three-phase alternating current or direct current. An electric arc is generated directly between the charge and the electrode, and the charge is melted at a high temperature by the electric arc, and then an oxidizer, slag-forming agent, ferroalloy, etc. are added to remove inclusions. The chemical composition and temperature of the molten steel are adjusted to the specified values and then injected into the ladle. Since the 1980s, electric furnaces have developed in the direction of large-scale, ultra-high power, direct current, continuity and automation, and the world's electric furnace steelmaking production technology has developed more rapidly. Electric furnace melting period The melting period of the traditional smelting process accounts for 50% to 70% of the entire smelting time, and electricity consumption accounts for 70% to 80%. Therefore, the length of the melting period

Furnace repair part and method of repairing furnace

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  EAF Furnace repair part: The working conditions of each part of the lining are different, and the damage is also different. The main parts of the lining damage are as follows: Furnace wall slag line: severely damaged by high-temperature arc radiation, chemical erosion and mechanical erosion of slag and steel, and oxygen blowing operations; Slag line hot spot: In particular, the hot spot is also severely corroded by the influence of high arc power and off-arc. The degree of damage at this point is often the basis for furnace replacement; Near the taphole brick : it is also easy to thin due to the erosion of slag steel; Both sides of the furnace door: It is often damaged by rapid cold and heat, scouring of flowing slag, and collision between operations and tools. EAF Furnace repair method: Furnace patching methods are divided into manual patching and mechanical gunning patching. According to the different mixing methods of the selected materials, they are divided int