531results about "Furnace linings" patented technology

Thermal insulation is provided for use in applications requiring continuous resistance to temperatures of 1260° C. without reaction with alumino-silicate firebricks, the insulation comprises fibers having a composition in wt %

• • 65%<SiO₂<86%
  • MgO<10%
  • 14%<CaO<28%
  • Al₂O₃<2%
  • ZrO₂<3%
  • B₂O₃<5%
  • P₂O₅<5%
  • 72%<SiO₂+ZrO₂+B₂O₃+5*P₂O₅
  • 95%<SiO₂+CaO+MgO+Al₂O₃+ZrO₂+B₂O₃+P₂O₅

Addition of elements selected from the group Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y or mixtures thereof improves fiber quality and the strength of blankets made from the fibers.

A composite high temperature insulator (A) includes a planar layer (10) having anisotropic thermal conductivity properties. A second planar layer (12) is formed from a rigid insulation material, such as a carbonized mixture of carbon fibers and a binder. The second layer is coextensive with the first layer and is preferably bonded thereto by a carbonaceous cement (44). When used to insulate a heat source, such as a furnace (50), convective heat is directed back to the source by the reflective surface (16) of the inner, anisotropic layer (10). Heat which enters the anisotropic layer is dissipated evenly through the plane of the layer along a plurality of heat paths defined by a plurality of layers (14) of flexible graphite. Accordingly, heat which reaches the outer, second layer (12) results in fewer hot spots than occur with a conventional rigid insulation material, thereby reducing the total amount of insulation material required to achieve a desired level of thermal insulation.

The invention discloses a high temperature furnace-grade curing carbon fiber thermal insulating material having simple technology and small coefficient of heat conductivity, and a production technology thereof, characterized in that the material is made of the carbon fiber by the steps of the preparation of a preform, densification, hot-vibration purification and machine processing; the invention is free from the processes of bonding, immersion, curing and charring in the preparation of the preform and has simple technology, great energy-saving property and environmental protection ability, the carbon fibers inside the preform are distributed in a crisscross pattern, strong in cohesive force, stable in structure and free from delamination, the coefficient of heat conductivity is not larger than 0.8 W/mK and the thermal insulating property is excellent; the product consists of the high-strength carbon fiber and carbon matrix and has outstanding performances such as high specific strength, good high temperature resistance, corrosion resistance and thermal insulating property, in addition, the product integrates the fire resistance and the thermal insulating property, can bear certain loads, and is an ideal upgraded product in taking the place of related high temperature furnace-grade graphite products and soft carbon felt.

A modular oven, such as a batch process oven, having a standardized set of self supporting, interconnectable panels which, when assembled, from a self-supporting heat containment shell, free of added structural support members. Also described are the self-supporting modular oven panels themselves having common roof, sidewall and end wall shell configuration and a method of assembling the panels such as in the expansion or conversion of a first modular oven assembly to a second assembly more conducive to current production requirements.

A cement free refractory mixture contains aluminum oxide, silicon carbide, fumed silica, aluminum metal, an anti-oxidant, reactive alumina, and a carbon-bearing material. The mixture can be formed by conventional techniques to create refractory articles to contain or direct the flow of liquid metals. Refractory articles formed by the mixture do not require firing to achieve an initial cure.

An inner lining for the steel shell of a carbothermic reduction furnace for the production of alumina has a base layer of graphite and a coating layer of refractory material. The refractory material is corundum (Al₂O₃) bound by Sialon (Si.Al.O.N). The lining structure provides protection against the molten slag and it is not attacked by the CO-rich melt furnace atmosphere. Further, the lining does not contaminate the melt and it provides an effective heat dissipation system in case of a power shut-off.

A gasifier internal refractory coating has at least one region of a sintered material containing at least 45% by weight of chromium oxide (Cr₂O₃) and at least 1% by weight of zirconium oxide, at least 20% by weight of the zirconium oxide (ZrO₂) being stabilized in the cubic and/or quadratic form.

The invention relates to a magnesia-hercynite brick and a preparation method thereof, belonging to the technical field of refractory materials. The magnesia-hercynite brick comprises the following chemical components in weight percent: 2.5 to 9.6% of Fe2O3, 2.9 to 12% of Al2O3 and 76-93% of MgO, the main crystalline phase displayed by XRD spectrum line is FeO.Al2O3. The preparation method comprises the steps of additionally adding a binding agent, carrying out compression moulding, drying, and baking at high temperature to obtain the magnesia-hercynite brick, which is simple and practicable. The magnesia-hercynite brick can be applied to the fields suitable to high temperature, in particular to clinkering zones of a novel rotary kiln utilizing a dry line method, thus solving the problem of Cr6 + pollution caused by the use of magnesite-chrome bricks in clinkering zones.

A highly zirconia-based refractory suitable for an electric melting furnace, which has a high electrical resistivity and does not exhibit a chipping off phenomenon and which is scarcely susceptible to extraction of components even when in contact with molten low alkali glass and, hence, is less susceptible to cracking during operation. The highly zirconia-based refractory that includes, as chemical components by mass %, from 85 to 95% of ZrO₂ in terms of inner percentage, from 3.0 to 10% of SiO₂ in terms of inner percentage, from 0.85 to 3.0% of Al₂O₃ in terms of inner percentage, substantially no Na₂O, from 0.01 to 0.5% of K₂O in terms of outer percentage, from 1.5 to 3.0% of SrO in terms of inner percentage, and from 0.1 to 2.0% of Nb₂O₅ and/or Ta₂O₅ as a value obtained by [(Nb₂O₅ content)+(Ta₂O₅ content/1.66)], in terms of inner percentage.

An alumina-based porous support with uniform physical properties is obtained in a rapid sintering process. An alumina raw material including a raw alumina powder and an inorganic binder is molded into an article, and the article is then sintered for 5 to 8 hours at 1520 to 1560 DEG C. using a roller hearth kiln.

The invention relates to a heat shield arrangement for a hot gas conducting structure, in particular a metal component of a gas turbine unit or combustion chamber, with the heat shield elements anchored adjacently on a support structure to cover a surface. Said heat shield elements each comprise a lateral groove, arranged in the region of the edge of the surface thereof facing the hot gas, at least two adjacent shield elements are connected by at least one seal element mounted in the groove. The seal element is embodied as a sealing flap, which may be displaced from a first position to a second position and vice versa, whereby the first position is an open position without a sealing effect and the second position is a closed position with a sealing effect. According to said method the sealing flap is moved from the first to the second position by the movement of a heat shield element.

A dry refractory composition having superior resistance to crack propagation. The dry refractory composition includes at least matrix material, filler lightweight material, and metal fibers. The composition also may include dense refractory aggregate. The dry refractory composition is suitable for use in containing heat in metal containment and other applications.

The present invention relates to a sintered product elaborated from a starting charge containing 75-99% of zircon, in mass percentage based on the oxides and having the following average weight chemical composition, in mass percentages based on the oxides

60%≦ZrO₂≦72.8%,

27%≦SiO₂≦36%,

0.1%≦B₂O₃+GeO₂+P₂O₅+Sb₂O₃+Nb₂O₅+Ta₂O₅+V₂O₅,

0.1%≦ZnO+PbO+CdO,

B₂O₃+GeO₂+P₂O₅+Sb₂O₃+Nb₂O₅+Ta₂O₅+V₂O₅+ZnO+PbO+CdO≦5%

0% ≦Al₂O₃+TiO₂+MgO+Fe₂O₃+NiO+MnO₂+CoO+CuO≦5%,

other oxides: ≦1.5%,

• for a total of 100%.

Notably used in a glass furnace.

A heat treating furnace capable of continuously performing binder removal and subsequent firing without requiring a complicated configuration and increasing the equipment size and cost, for example, for degreasing a ceramic molding which is to be fired in a process for manufacturing a ceramic electronic component. A heat insulator is disposed to surround a heat treatment region in a case, and a reflector is disposed between the inner wall of the case and the insulator in order to reflect heat transferred from the heat treatment region through the heat insulator. A module heater including a heater embedded in the insulator is used. As the reflector, there is used a reflector having a structure in which a plurality of thin plates is arranged so that the main surfaces are arranged in parallel to each other with a predetermined space between the adjacent main surfaces.

An apparatus for treating, in particular purifying or degassing, molten metal (40), comprising a component (10) exposable to molten metal to be treated and means (13) for imparting a rotary motion to the molten metal (40) about a substantially vertical axis. The apparatus is so arranged that during use at least part of a wear-exposed surface of the component (10) is temporarily or permanently in contact with molten metal (40), the contacting molten metal being in motion relative to the wear-exposed surface. The wear-exposed surface is coated with a slurry-applied protective coating (18A,18B) of refractory material in a heat stable binder, in particular an inorganic colloidal and/or polymeric binder, protecting the wear-exposed surface against erosion, oxidation and corrosion.

The invention relates to a technical proposal in which the tapping runner of a single taphole blast furnace is transformed into an iron-storage iron runner to enable the iron runner to have long service life. The invention uses the method of elevating the taphole elevation of a skimmer and lowering a main runner, so that more hot metal is always stored in the main tapping runner, thereby buffering the impact of hot metal on the runner bottom and improving the application environment of refractory of the main runner. The invention solves the problem of the explosion-proof performance of runner iron castable, thus achieving the purpose that the tapping runner of the single taphole blast furnace uses refractory castable to substitute the traditional ramming material. Both the surface and the inner side of the runner lining made of castable are compact, so the problem that the surface of the ramming material is compact and the inner side is loose does not occur, so that the service life of the iron runner can be substantially prolonged, and the consumption of iron runner material of iron yield per unit is also reduced, which not only improves the economic benefits, but also has the advantages of resource conservation and waste slag reduction, and substantially reduces the labor intensity of the maintenance work of furnacemen.

The invention relates to a powder comprising more than 70% of refractory particles, in weight percent relative to the weight of the powder, a particle of said powder being classed in the fraction called “matrix” or in the fraction called “aggregate”, according to whether it is smaller than, or equal to 100 μm, or larger than 100 μm, respectively, said powder comprising, in weight percent relative to the weight of the powder: between 0.1% and 18% of particles of a heat-activatable binder, called “heat-activatable binder particles”; and more than 40% of refractory particles, called “ATZ particles”, having the following chemical composition, in weight percentages on the basis of the oxides of said ATZ particles: 10%≦Al₂O₃≦55%; 35%≦TiO₂≦80%; 1%≦MgO+Cr₂O₃≦10%; 8%≦ZrO₂≦20%; SiO₂≦8%.

A gasifier comprising an interior wall on which a layer is applied or an interior wall protected by an assembly of blocks, said layer or said blocks having at least one region of a sintered material containing:

• • i) at least 25% by weight of chromium oxide Cr₂O₃; and
  • ii) at least 1% by weight of zirconium oxide, wherein at least 20% by weight of said zirconium oxide ZrO₂ is stabilized in the cubic and/or quadratic form.

An alumina sintered compact includes at least two layers including an internal layer and a surface layer formed on the surface of the internal layer, which internal layer is composed of alumina crystal grains formed by sintering of a fine alumina powder, and which surface layer is composed of alumina crystal grains formed by grain growth of a fine alumina powder and having a mean grain size larger than that of the alumina crystal grains of the internal layer. This alumina sintered compact can prevent the accumulation of PbO in a surface area while controlling the absorption of PbO.