51results about How to "High thermal strength" patented technology

The invention discloses wear corrosion resistant castable prepared from a bauxite-based homogenous material and a preparation method thereof, which belong to the technical field of castable refractory. In the invention, by using the characteristics of the bauxite-based homogenous material, such as homogeneous chemical components and structure, stable performance, mulite main crystal phase, small linear change, high high-temperature strength and certain flexibility due to mutual insertion of micro crystals and the like, the shortcomings of low middle-temperature strength and poor wear resistance and alkali corrosion resistance of the conventional high-aluminum bauxite castable are overcome, and the problems of low middle-temperature strength, poor wear resistance and poor alkali, chloride and sulphur corrosion resistance of the conventional high-aluminum and corundum castable are effectively solved. The wear and corrosion resistant castable with high middle-temperature performance is prepared. The wear corrosion resistant castable and the preparation method thereof have the advantages of small fluctuation of water adding amount in construction, stable usability, reduction rate of partial corrosion, prolonged service life and wide application to a kiln hood, a grate cooler, a tertiary air duct and a decomposing furnace of a dry process cement kiln and relative parts of other ceramic and petrified thermo-technical kilns and the like.

The invention discloses a cement-free in-situ silicon nitride combined silicon carbide prefabricated member and a preparation method thereof. The cement-free in-situ silicon nitride combined silicon carbide prefabricated member is formed by taking silicon carbide, metallic silicon powder, alumina micro powder, silicon dioxide micro powder and hydraulic alumina as materials and additionally adding dispersing agent, water or silica sol. The prefabricated member is formed by adopting a vibration pouring method, is cured and dried and subjected to high-temperature nitrogen treatment in a high-purity flowing nitrogen gas. The prefabricated member has the advantages of easy construction, low cost, flexible product shape, high hot strength, strong corrosion resistance, high wear resistance and the like and is widely applied to parts strictly requiring the hot-state performance, such as a wind-force pipeline of a cement kiln, a blast-furnace throat, an air port, a delivery pipeline of melt metal, a garbage incinerator and the like.

The invention relates to a prefabricated part of a coal injection pipe head, belonging to the field of refractory materials. The prefabricated part is prepared by the following steps: evenly mixing sintered mullite, white corundum fine powder, carborundum, sillimanite, alpha-alumina micropowder, silica micropowder, pure calcium aluminate cement and water reducing agent, which are crushed to specified granules, with water according to parts by weight; and carrying out vibration casting and conventional curing, and baking. The product has the advantages of high thermal-state strength, high temperature resistance, wear resistance, stable performance, favorable integrity, favorable anti-stripping property, favorable scour resistance and the like. The prefabricated part is directly sheathed onthe coal injection pipe head, and thus, is convenient for construction and maintenance and is safe and reliable, thereby greatly shortening the construction period.

The invention discloses an Al2O3-SiC-C refractory brick for torpedo ladles and a preparation method thereof, which relate to the fields of refractory bricks and preparation methods thereof. The refractory brick is composed of the following raw materials in parts by weight: 25-35 parts of super bauxite clinker, 15-25 parts of corundum particles with a particle size of 0.2-1 mm, 3-5 parts of a phenolic resin, 12-18 parts of fine corundum powder, 10-15 parts of fine SiC powder, 3-5 parts of alumina micro-powder with a particle size of 1-5mu m, 8-15 parts of natural flake graphite and 2-4 parts of Si powder; and Si3N4, Si2N2O and Sialon nonoxide reinforced phases are generated in the refractory brick. The preparation method of the refractory brick comprises the steps of material mixing, forming and nitriding treatment. Compared with traditional Al2O3-SiC-C bricks for torpedo ladles, the Al2O3-SiC-C refractory brick for torpedo ladles disclosed by the invention can significantly improve the hot strength, scour resistance and thermal shock resistance of a brick body.

The invention relates to an aluminum oxide-silicon carbide-carbonaceous cement-free castable suitable for construction in winter. The technical scheme is as follows: the castable comprises the following components in percentage by weight: 58-62wt% of dense corundum particles; 6-10 wt% of silicon carbide particles; 2-3 wt% of spherical asphalt; 4-10 wt% of alumina micro powder; 4 to 5 wt% of silicon dioxide micro powder; 7-10 wt% of silicon carbide powder; 1 to 1.5 wt% of silicon powder; 0.1-0.15 wt% of polyacrylic acid; 6-9 wt% of dense corundum fine powder; 0.04-0.1 wt% of water-soluble fibers; and 0.2-0.3 wt% of caustic-burned magnesia powder. During construction, when the environment temperature and the water temperature are both lower than 15 DEG C, after construction is completed, a pouring body is cured at 33-38 DEG C until the pouring body is completely cured. The concrete has the advantages of being small in water adding amount, short in setting time and high in construction site safety, is good in compactness, free of cement, high in thermal strength and good in various technical indexes, and particularly completely meets the requirements of construction in winter.

The invention relates to a novel heat insulation structure of a coke oven foundation top plate. The novel heat insulation structure comprises an integral castable layer, transverse preformed holes andlongitudinal preformed holes. Side beams are arranged on the two sides of a foundation top plate, and the top faces of the side beams are higher than the top face of the foundation top plate, so thata groove structure is formed in the top of the foundation top plate. The integral castable layer is arranged in a groove structure; the integral castable layer is provided with at least one layer oftransverse preformed holes and at least one layer of longitudinal preformed holes, and each of the transverse preformed holes and the longitudinal preformed holes includes a plurality of preformed holes formed in parallel. The refractory castable layer is adopted to replace a traditional refractory brick masonry structure, and a protective layer is formed on the coke oven foundation top plate in apouring mode; in the pouring process, holes are reserved through pre-buried plastic pipes, and the longitudinally and transversely arranged hole structures can play a good role in heat insulation, sothat the temperature of foundation top plate concrete is reduced, and the service life of the foundation top plate concrete is prolonged; meanwhile, the coke oven basement temperature is reduced, andcoke oven operation conditions are improved.

The invention discloses a preparation method of an iron runner sialon casting body. The method comprises the following step: embedding a pipe easy to burn out in an iron runner casting body; and forming a pipe inlet and a pipe outlet in the wall of an iron runner. When the iron runner is used, the pipe easy to burn out is burnt out to form a channel, nitrogen is fed in the channel; and when the flows of the inlet and the outlet of the nitrogen channel are the same, the outlet of the channel is closed and the feeding of the nitrogen is stopped; and a filling material is pressed into the channel. The air-cooled iron runner sialon casting body prepared by using the method is high in cooling efficiency, so that the service life of the iron runner is further prolonged. The integrated iron runner sialon casting body can be used for improving the whole thermal state strength of the iron runner by dozens of times; and the iron runner material contains nitrides, so that a wetting angle of the iron runner material to slag iron is enlarged. Thus, the slag erosion resistance and the penetration resistance of the iron runner are greatly improved. Therefore, the service life of the iron runner is prolonged. As a result, the cost of an enterprise is reduced; and the generation of industrial wastes and the waste of fire-resistant raw material resources are reduced, namely, the environmental-friendly effect is achieved.

The invention relates to a cement-free iron runner castable including, by weight, 33-45 parts of brown corundum, 13-23 parts of white corundum, 10-20 parts of SiC, 10-15 parts of alumina powder, 4-12parts of SiC-SiAlON powder, 1-2 parts of calcium carbide powder, 3-5 parts of Siox X-Zero powder and 0.15-0.2 parts of explosive-proofing fibers. The castable has good high temperature mechanical strength and strong anti-slag scouring performance, is good in breathability and can achieve rapid constructure of an iron runner.

The invention relates to environment-friendly aqueous long-life self-flowing repairing mix for a converter and a preparation method thereof. The invention is characterized by utilizing high purity fused magnesia, high purity sintered magnesia and fine silica powder as the main raw materials; utilizing one or more of ferrosilicon powder, silicon carbide powder, fine metal powder and the like as the burning accelerating agent to realize rapid sintering of the self-flowing repairing mix; utilizing one or two of citric acid, boric acid, tartaric acid, oxalic acid and the like as the retarders to realize the construction time of the self-flowing repairing mix; and utilizing fine MgO and SiO2 powder, thus improving the mobility and the sintering property of the material, enhancing the medium and high temperature strength and boosting the washing resistance and the impact resistance of the material. The self-flowing repairing mix has high hot strength and excellent erosion resistance and liquid steel washing resistance and can be continuously used for 50h after once repairing under the condition of smelting multi-variety steel in the converter, thus greatly improving the efficiency of converter steelmaking, reducing the consumption of refractories and prolonging the lives of the lining materials of the converter.

The invention provides a method for upgrading and desulfurizing high-sulfur fat coal, which relates to the technical field of coking and comprises the following steps: (a) mixing high-sulfur fat coal, an organic sulfur removal agent, titanium dioxide and nickel fluoborate to form first slurry; (b) carrying out heating reaction on the first slurry, and separating to obtain a first liquid material and a first solid material; (c) mixing the first solid material and washing oil to form second slurry; (d) carrying out heating and pressurizing reaction on the second slurry, and separating to obtain a second liquid material and a second solid material; (e) carrying out flash evaporation on the second liquid material to obtain an organic solvent and a third solid material; and drying the third solid material to obtain desulfurized coal. According to the method, 50% of organic sulfur and 100% of inorganic sulfur can be removed on the premise that the caking property of the high-sulfur fat coal is not damaged, the utilization rate of precious high-quality coking coal is reduced while the utilization rate of inferior coke is increased, and good economic benefits and environmental benefits are achieved.

The invention discloses a solid waste pelletizing process and an efficient sintering method thereof, waste magnesium oxide powder, iron-containing solid waste and a binder are adopted as raw materials, and solid waste pellets are prepared after burdening, surface modification and pelletizing; and mixing the solid waste pellets and a mineral mixture prepared by adopting a mixing granulation process as sintering raw materials, and sequentially carrying out material distribution, ignition, sintering, cooling and whole grain screening to obtain a finished product of sintered ore, the binder is prepared from waste magnesium oxide sludge, municipal sludge, first quick lime and corn starch; the waste magnesium oxide powder and the waste magnesium oxide sludge are magnesium oxide wastes. According to the method, the magnesium oxide waste, the municipal sludge, the rotary hearth furnace fine powder and other solid wastes inside and outside the steel plant are fully recycled, local concentrated heterogeneous sintering of magnesium oxide is realized, the adverse effect of uniform distribution of MgO on the sintering productivity is avoided, the quality of solid waste pellets is improved, and the production cost is reduced. Therefore, the quality index and the heat energy utilization efficiency of the finished sinter are remarkably improved, and fuel consumption and CO2 emission are reduced.

A method for making dies for die casting, and relative die, includes designing moulding parts of the die as plurality of sub-inserts. Each sub-insert of the plurality is bordered by boundary lines defined on the basis of a simulation of thermo mechanical behaviour of the die in operation. The simulation is performed by a processor of a computer and the behaviour is the behaviour of the die if the die were a single piece. The method also includes producing the plurality of sub-inserts and assembling the sub-inserts of the plurality with attachment means, so as to form the die.