32results about How to "Improve medium and high temperature strength" patented technology

The present invention relates to amorphous refractory material, and is especially one kind of no-water stemming material for blast furnace taphole and its preparation process. The no-water stemming material is prepared with coke powder 15-25 wt%, clay 10-20 wt%, bauxite corundum 20-36 wt%, silicon carbide 10-20 wt%, asphalt 8-16 wt%, sericite 5-9 wt%, additive 1-5 wt% and binding agent 12-22 wt%, and through crushing, sieving, pre-mixing, rolling, kneading and extruding. The no-water stemming material has excellent plasticity and sintering performance, high strength at high and middle temperature and high slag and molten iron flush resistance, and can meet the requirement of high strength smelting in blast furnace.

The invention discloses a method for producing a waterless taphole mix for a blast furnace from high-alumina waste refractory materials. The produced low-cost waterless taphole mix can satisfy the operating requirements for plugging tapholes of large and medium blast furnaces. The method comprises the selection of raw materials for production, the processing of the raw materials for production, the proportioning of the raw materials for production, and the production process. The waterless taphole mix produced by the method has the characteristics of low cost, good plasticity and sintering property, high middle-and-high-temperature strength, favorable slag and iron erosion resistance and the like, and can completely satisfy the operating requirements of large and medium blast furnaces. Compared with the existing waterless taphole mix, the cost can be reduced by 40-60%; since a great amount of waste refractory materials are used, the emission of the solid waste can be decreased, and a great amount of high-quality refractory materials such as brown corundum, premium / extra grade alumina and the like can be saved; and meanwhile, the energy consumption and the emission of carbon dioxide gas during the smelting of brown corundum and premium / extra grade alumina can be decreased.

The invention relates to an aluminum nitride reinforced pouring material for a chute column of a CDQ coke oven and a preparation method thereof. The technical solution is: 45-65wt% mullite, 15-35wt% silicon carbide, 2-8wt% inorganic-metal composite microcapsules, 4-6wt% α-alumina powder, 2-4wt% Silica powder and 4-6wt% calcium aluminate cement are used as raw materials, and 0.1-0.3wt% catalyst and 0.1-0.3wt% water reducer are used as additives. First mix the inorganic-metal composite microcapsules and the catalyst to obtain a premix; then mix the premix, water reducer and other raw materials, and stir evenly to obtain aluminum nitride reinforced CDQ oven chute castables . The aluminum nitride reinforced castable for CDQ coke oven chute column prepared by the invention has good hydration resistance, high production stability and good fluidity; the use results show that it has excellent mechanical properties at medium and high temperatures, wear resistance and thermal shock Good stability, long life, energy saving and environmental protection.

The invention discloses a light tundish working lining and a method for preparing the same. Ingredients for the light tundish working lining comprise waste magnesia-carbon bricks, magnesite tailing, aluminum oxide, fibers, compound bonding agents and additives. The method for preparing the light tundish working lining includes dry vibration forming or wet smearing forming. The light tundish working lining and the method have the advantages that the light tundish working lining prepared by the aid of the method is low in volume density, erosion rate, cost and consumption and long in service life, energy can be saved, and the like. Besides, the problem of excessive consumption of resources of existing refractory raw materials (including waste magnesia-carbon brick reclaimed materials and thelike), the problems in the aspects of energy conservation and heat preservation and the like can be solved by the aid of the light tundish working lining and the method.

The invention discloses an anti-permeation type tundish light coating and a preparation method thereof. The anti-permeation type tundish light coating comprises the following components in parts by weight: 73-99 parts of magnesite and / or forsterite with the granularity less than or equal to 1mm, 0.1-15 parts of quartz sand, 0.2-4 parts of sulfamic acid, 0.1-3.0 parts of an organic plasticizer agent, 0.5-5 parts of composite fiber, 0.02-0.25 part of high-efficiency air entraining agent and 0.01-0.15 part of metal aluminum powder. The coating disclosed by the invention is small in volume density, high in pressure resisting intensity after being baked, small in low melt and capable of effectively preventing slag permeation and solving the problems of a conventional light coating in construction, baking and use.

The invention relates to refractory materials applied to the field of iron and steel smelting, in particular to a high-aluminum castable for torpedo ladle permanent layers. The high-aluminum castablefor torpedo ladle permanent layers comprises, by weight, 50-70% of mullite brick reclaimed materials, 15-35% of bauxite chamotte, 1-5% of calcium aluminate cement, 2-8% of pyrophyllite, 2.5-5.5% of silica powder, 0.01-0.04% of polypropylene fiber and 0.06-0.49% of water reducing agent. The change of volume of high-aluminum castable before and after sintering is small so that the potential safety hazard of big gap formed between a working layer and the permanent layer due to volume change of high-aluminum castable is reduced. Besides, the high-aluminum castable has good medium-and-high temperature strength, the risk of pulverization of the high-aluminum castable caused by low strength during application is avoided.

The invention relates to a T91 water wall tube row welding technology. The welding technology comprises the steps of (1) cleaning before welding; (2) welding material preparation: preparing welding wires and flux, and performing baking before flux use, wherein the baking temperature is in a range of 250 DEG C to 400 DEG C, and the baking time ranges from 0.5h to 3h; (3) spot welding before welding: using R317 welding wires to flat steel and T91tube electric welding, wherein the welding strips are needed to be baked; (4) preheating before welding: performing preheating before welding to enable all portions of materials to be welded to be uniform in heating; (5) tube row welding: performing welding in the condition of the 300A-320A welding current, 26V-27V welding voltage and 80mm / min-90mm / min and performing coverage with asbestos immediately after front welding seams are welded; (6) hydrogen removal after welding; (7) detection; (8) thermal treatment. The welding technology is simple and convenient to operate, covering through insulation cotton is performed after welding, and accordingly, cracks due to rapid cooling can be prevented.

The invention relates to a Y-PSZ strengthened fireproof material and a preparation process thereof. The fireproof material is prepared from the following raw materials in percentage by weight: 28 to 30 percent of high-purity fine magnesia, 27 to 30 percent of high-purity crude magnesia, 17 to 21 percent of fused magnesia, 15 to 20 percent of aluminum magnesium spinel, 1.5 to 4 percent of monatomicsilicon, 1.5 to 3 percent of carbon nano-tube and 0.5 to 1.0 percent of an additive. The product has high mechanical property, heat stability and thermal shock resistance, has high medium-temperatureand high-temperature strength, is safe and non-toxic, and is an environment-friendly material; the use requirement of a binding agent is avoided and the preparation process is environmentally friendly and clean; the Y-PSZ is added, so that the toughening effect is achieved, and the medium-temperature and high-temperature strength, the thermal shock resistance and the slag corrosion resistance ofthe material are obviously improved.

The invention relates to a technology for preparation of refractory material, and especially to a composite refractory of non-oxidized substance used in a hot-metal launder of consecutive pre-processing. The composite refractory of non-oxidized substance used in a hot-metal launder is characterized in that it contains (wt %) 50-70 % of corundum material, 15-30 % of silicon carbide, 3-10 % of silicon nitride, 3-10 % of silicon nitride tiny powder, 1-5 % of charcoal material, 1-3 % of silicon anti-oxidization agent, 6-15 % of additional silicasol astringent, and a few additives containing anti-knock agent and dispersing agent with 0.15-1.5 % by wt. The refractory material of the said invention can resist the erosion of the hot-metal and the molten ash and is of strong erosion ability, uniform and high-integrity structure, high intensity at a medium-high-temperature, strong stability of resistance to heat shocks and of volume of material, and strong resistance to oxidation, so it adapts to the process requirement of the desired hot-metal launder of consecutive pre-processing.

The invention discloses a low carbon magnesia-alumina-carbon brick combining ceramics at a high temperature and a preparation method thereof. The preparation method comprises the following steps: uniformly mixing raw materials in the low-carbon magnesia-alumina-carbon brick, pressing to form a green body, and then baking the green body for 6 to 12 hours at 150 to 220 DEG C. The low carbon magnesia-alumina-carbon brick is prepared from the following raw materials in parts by weight: 40 to 50 parts of fused magnesite particles, 10 to 25 parts of fused magnesite fine powder, 10 to 25 parts of high-alumina bauxite particles, 5 to 15 parts of corundum fine powder, 2 to 4 parts of zirconite particles, 4 to 8 parts of zirconite fine powder, 2 to 4 parts of crystalline flake graphite, 1 to 2 parts of metal Al fibers, 1 to 2 parts of elementary substance Si fibers and 2 to 4 parts of binding agents. Compared with the traditional carbon-combined low carbon magnesia-alumina-carbon brick, the low carbon magnesia-alumina-carbon brick is excellent in medium-high-temperature strength, thermal shock resistance and oxidation resistance.

The invention discloses a corundum-spinel repair material for carbon-free steel ladle working lining and a preparation method thereof. The repair material includes the following components in parts by mass: 30-80 parts of corundum composite material, 15 parts of aluminum-magnesium spinel ~45 parts, 2-10 parts of alumina micropowder, 3-8 parts of pure calcium aluminate cement, 1-7 parts of plasticizer, 0.1-0.3 parts of water reducing agent, 0.03-0.3 parts of explosion-proof fiber. The corundum-spinel repair material for carbon-free ladle working lining of the invention has good adhesion performance, appropriate spreading performance, high medium and high temperature strength, good overall performance, excellent anti-scour and anti-erosion performance, long service life, and economical resources and reduce carbon emissions.