The charge to mass production and products for structurally stable linings

 

(57) Abstract:

Usage: in the most worn parts of the lining of casting ladles and converters, electric furnaces and other units of ferrous and nonferrous metallurgy. The inventive composition comprises, in wt.%: granular and dispersed sintered magnesia powder 75 - 93, granular and dispersed fused aluminasilica spinel 7 - 25, the ratio of the granular and dispersed sintered magnesia powder is from 1.14 to 2.75, and the ratio of granular and dispersed fused aluminasilica spinel is from 2.3 to 9.0. Granular fused aluminasilica spinel has raznovrsnosti crystals is not less than 2.0. 1 C.p. f-crystals, 2 tab.

The invention relates to refractory industry and can be used for the manufacture of refractory products used in the most worn parts of the lining of casting ladles and converters, electric furnaces and other units of ferrous and nonferrous metallurgy.

Known magnesia-senility refractories containing periclase, magnesia-alumina spinel derived from a mixture of the following composition: periclase fraction 3-1 in periclase fracc known refractories is the low thermal stability of the products, component 6 thermal cycles (1300oC water)

Known mixture for the manufacture of refractories containing sintered periclase fraction 3 mm and less 2-85 wt. fused aluminasilica spinel fraction 2 mm and less 4-80 wt. fused corundum particles less than 0.1 mm 4-25 wt. [2]

The disadvantages of the known charge is that the porcelain is secondary spinlooptime, accompanied by a large volume expansion that leads to loosening of the structure of refractories and reduce its density, and low thermal stability of the obtained products, component 6.7 thermal cycles (1300oC water).

Most similar to the claimed technical solution is to charge for making pricesonline refractory products containing granular and dispersed (it) sintered magnesia powder and granular fused aluminasilica spinel fraction 3-0,5 mm in the amount of 30 wt. [3]

The disadvantages of the known charge is reduced thermal resistance and increased the diameter of the channel pore, leading to reduced lacoustics due to the penetration of slag into the pores of products.

The task to be solved by the invention is the which can be obtained by carrying out the invention, is that the content in the charge of the dispersed molten aluminasilica spinel (fractions less than 0.09 mm) provides a good sintering and the formation of a dense grain layers. The reduction of diameter of the channel pore contributes to the creation of structurally stable linings, allowing you to get rid of penetration of the slag melt inside linings. It determines the nature of lining wear only on the mechanism of slow aging and erosion, which is only a thin crust boundary of refractories. When this lining may serve to a low residual thickness, not burn out and not shrivas.

In addition, elongated crystals granular fused aluminasilica spinel (with raznovrsnosti not less than 2,0) contribute to the creation of durable ceramic "crock" and prevent cracking of the lining when exposed to contrasting temperatures, resulting in significantly enhanced thermal stability of refractory products.

The invention consists in that the charge to mass production and products for structurally stable linings, including granular and dispersed sintered magnesia powder and granular fused aluminasilica spine the components, wt. granular and dispersed sintered magnesia powder 75-93, granular and dispersed fused aluminasilica spinel 7-25, the ratio of the granular and dispersed sintered magnesia powder is from 1.14 to 2.75, and the ratio of granular and dispersed fused aluminasilica spinel is from 2.3 to 9.0. In addition, granular fused aluminasilica spinel has raznovrsnosti crystals is not less than 2.0.

The manufacturing technology of the proposed charge masses and products for structurally stable linings is as follows.

Granular fused aluminasilica spinel fraction 3-0,09 mm and granular sintered magnesia powder fraction 3-0,09 mm is stirred for 1.5-3 min of mixing the edge-runner mills. Then moisturize with a solution of lignosulfonates density of 1.22 g/cm3and add the dispersed molten aluminasilica spinel particles less than 0.09 mm, and dispersed sintered magnesia powder, the fraction of 0.09 mm. All this is stirred for 3-5 min, then from the mass of pressed products at specific pressure of at least 140 H/mm2and fired in a tunnel kiln aged for 4 hours at a temperature of 165020oC.

Anasto crystals is not less than 2.0 prepared by melting aluminasilica spinel in the arc of ore-thermal furnaces (unit, discharge, release), with the optimal ratio of the diameter of the baths to the diameter of the electrodes in the conditions of cooling of the molds and cover the tub. This creates a temperature gradient that provides directional growth of spinel crystals. Then by crushing the crystals receive grain spinel with raznovrsnoscu not less than 2.0. Raznovrsnosti crystals aluminasilica spinel influences the strength as prevents cracking when exposed to contrasting temperatures.

The compositions of the prepared blends are given in table. 1.

Then determine thermal stability, tensile strength under compression, open and channel porosity, maximum pore diameter, coefficient of permeability, slag and additional linear shrinkage.

Properties of products prepared from the corresponding charges shown in the table. 2.

The maximum diameter of the channel pore is determined by microscopic examination of thin sections in reflected light. The slag is determined by the volume change of the deepening of the crucible. The definition of the other indicators of the quality of the products is done according to Standards.

The range boundary values introduction in charge processed by alnoy aluminasilica spinel less than 7 wt. its influence on the properties of refractory products slightly, and when more content 25 wt. is the degradation of physical and ceramic properties of the products.

The content processed aluminasilica spinel (granular and dispersed in the mixture in amount 7-25 wt. provides resistance lining to the sharp increase of temperature, because it creates the microstructure of the lining that covers the sharp thermal expansion. This is due to the presence of closed pores in the refractory, which allow to compensate for thermal expansion during thermal shock.

The ratio of granular and dispersed fused aluminasilica spinel average of from 2.3 to 9.0, along with heat resistance enables the creation of structures that are resistant to infiltration and slag corrosion, due to its low porosity, confirmed and low gas permeability, and also due to the lack of additional linear shrinkage of the lining, which provides a high slag refractories.

The ratio of granular and dispersed sintered magnesia powder in the range from 1.14 to 2.75 provides sufficient strength intergranular communication granular and dispersed periclase and together

As can be seen from the table. 2, the proposed charge has the best performance for thermal stability in comparison with the refractory materials of known composition and a much smaller diameter of the channel pore.

Application of refractories of the proposed charge will increase the resistance linings and duration of campaigns thermal units, in particular of steel-pouring ladles, and the intensification of technological processes in aggregates of ferrous and nonferrous metallurgy, as these refractories can be used as in the area of the molten metal and the slag zone, and also to reduce the consumption of refractory products and the cost of repairs.

1. The charge to mass production and products for structurally stable linings, including granular and dispersed sintered magnesia powder and granular fused aluminasilica spinel, characterized in that it further comprises a dispersion of fused aluminasilica spinel in the following ratio, wt.

Granular and dispersed sintered magnesia powder 75 93

Granular and dispersed fused aluminasilica spinel 7 25

the ratio of granular and dispersed sintered magnesia powder SOS is tx2">

2. The charge under item 1, characterized in that the granular fused aluminasilica spinel has raznovrsnosti crystals is not less than 2.

 

Same patents:

The invention relates to the mass production of basic refractories and mass, and can be used for linings melting units ferrous and nonferrous metallurgy, as well as rotary kilns

The invention relates to refractory industry and can be used for the manufacture of pricesonline of products used in the most worn parts of the lining of casting ladles and converters, electric furnaces and other units of ferrous and nonferrous metallurgy

The invention relates to refractory industry, namely: the production of carbon-containing refractories based on magnesia and alumomagnesium spinel used in the linings of smelting and metal processing units

FIELD: refractory body technology, in particular refractory bodies for facing of metallurgical aggregates.

SUBSTANCE: claimed carbonized refractory body contains (mass %): alumina-magnesia grained filler 19.0-26.0; fine ground complex filler 15.0-35.0; plasticizer 0.9-1.6; carbon-containing resin 2.9-3.8; and balance: grained periclase filler. Said fine ground complex filler contains (mass %): periclase 50.0-81.0; graphite 11.0-27.0; corundum 3.0-9.0; zirconium dioxide 2.0-6.0; metal Al 3.0-8.0. Carbonized refractory body is obtained by introduction of alumina-magnesia grained filler into stream of grained periclase filler; adding of plasticizer; capsulation of grain surface and subsequent introduction of fine ground complex, carbon-containing resin filler, followed by agitation to provide carbonized body with apparent density of 1.65-2.0 g/cm3. Obtained body is discharged from agitator and seasoned for at least 3 h/ Then articles are formed and heat treated at temperature higher than 1500C.

EFFECT: refractory bodies with improved quality.

3 cl, 6 ex, 1 tbl

FIELD: metallurgy; production of spinel refractory material for lining smelting furnaces.

SUBSTANCE: the invention is pertaining to the field of metallurgy, in particular, for production of spinel refractory material used for lining smelting furnaces, for example, for smelting of aluminum alloys. The mass for production a spinel refractory material consists of (in mass %): an under-earth - 3-5, a sintering additive in the form of a mix of boric acid and sodium tripolyphosphate taken in the ratio from 1:9 up to 9:1 - 4.5-6.5, a temporary binder - 2-3 and a melted aluminum-magnesia spinel - the rest. It is preferable to use aluminum-magnesia spinel containing fractions of <0063 mm within the limits of 30-40 mass %. The sintering additive and the fine grain composition of aluminum-magnesia spinel ensure a good sintering of the refractory mass and production of a dense refractory material with a low accessible porosity and a high mechanical strength. The refractory material is inertial to a melt of metal and is not impregnated with it, that ensures parallax purity of the smelted metal and eliminates metal loss with lining.

EFFECT: the invention ensures production of a dense refractory material with a low accessible porosity, a high mechanical strength, a good mass sintering, a parallax purity of the smelted metal excluding the metal loss with lining.

2 cl, 2 tbl

FIELD: refractory materials.

SUBSTANCE: invention proposes the refractory gunite-mass designated mainly for consumable fettling intermediate ladle for machine of continuous casting blanks. Refractory gunite-mass comprises components in the following ratio, wt.-%: organic fiber, 0.1-1.0; inorganic fiber, 0.1-0.4; polymeric binding agent with an ester-base plasticizer, 2.0-5.0; periclase-containing filling agent, the balance. Refractory gunite-mass can comprise also 0.5-4.0 wt.-% of sodium tripolyphosphate and 0.2-2.0 wt.-% of phenolformaldehyde resin. Invention provides enhancing porosity, reducing heat conductivity, enhancing mechanical strength and adhesion in applying, improving exploitation properties and possibility for applying the thickened layer of gunite-mass.

EFFECT: improved and valuable properties of mass.

2 cl, 1 tbl

FIELD: refractory article producing industry, possibly manufacture and restoration of linings of high-temperature aggregates in ferrous and non-ferrous metallurgy.

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EFFECT: improved resistance against melt metals and slag, reduced heat conductance, good adhesion with aggregate lining at applying mass, at heating it and at using aggregates.

2 tbl

FIELD: construction.

SUBSTANCE: periclase-spinel refractory items are manufactured from a mixture containing granular and disperse periclase, granular zirconium containing alumomagnesium spinel (containing 1-4 wt % TiO2) and disperse zirconium containing additive in the form of baddeleyite or industrial zirconium dioxide at the following ratio of components, wt %: granular periclase as a basis, granular alumo-magnesium spinel (containing 1-4 wt % TiO2) - 7-25, disperse periclase of 0.063-0 mm fractions - 10-36, disperse zirconium containing additive of 0.063-0 mm fraction - 0.6-5.5.

EFFECT: proposed periclase-spinel refractory items are provided with high mechanical strength and high stability to Portland cement clinker at high temperatures.

2 tbl, 1 ex

FIELD: construction.

SUBSTANCE: method for manufacturing of periclase-spinel fire-resistant mass for production of objects includes preparation of components, mixing of grain component represented by periclase and aluminium-magnesium spinel and dispersed component of 0.063-0 mm fraction represented by periclase and zirconium-containing additive in the form of brazilite or technical zirconium dioxide in mixer. At the same time mixing of components is carried out until 2-10 wt % of dispersed periclase is produced in mass with fraction of 0.063-0 mm as a result of grainy periclase abrasion in mixer, at the following ratio of components, wt %: grainy periclase - base; grainy aluminium-magnesium spinel - 7-25; disperse periclase of fraction 0.063-0 mm, loaded into mixer - 10-32; disperse zirconium-containing additive of fraction 0.063-0 mm in the form of brazilite or technical zirconium dioxide - 0.6-5.5, at the same time total content of disperse component of fraction 0.063-0 mm in mass makes 25-37 wt %.

EFFECT: improved strength in case of objects compression and twisting.

2 cl, 1 ex, 4 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to coarse-ceramic refractory material and a refractory article. According to the invention, the coarse-ceramic refractory material contains at least one granular refractory mineral basic component from basic refractory raw material based on MgO or MgO and CaO, and at least one granular refractory mineral additive which gives elasticity, in form of forsterite or forsterite material containing 50 wt % of a fraction with particle size of mainly 1-6 mm. The additive used can be a mixture which forms forsterite material, mainly in form of moulted parts, such as granules or briquettes with grain size between 0.3 and 8 mm. Said additive is contained in the refractory material in amount of 3-30 wt %.

EFFECT: high resistance of the refractory material to molten silicates and resistance to differential temperature.

20 cl, 1 tbl, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a heat-resistant ceramic article for facing high-temperature ferrous and non-ferrous metallurgy assemblies, as well as mineral material kilns. The moulded fire-resistant ceramic article is made using an additive formed from a solidified melt and consisting of ≥95 wt % MgO and calcium zirconate, with MgO content between 45 wt % and 65 wt % and content of calcium zirconate between 35 wt % and 55 wt %. The moulded heat-resistant article with a MgO-based matrix contains said additive in amount of 3-30 wt %, and consists of more than 95 wt % periclase and calcium zirconate structural phases.

EFFECT: improved fracture mechanics properties of articles.

13 cl, 1 tbl, 1 dwg

FIELD: metallurgy.

SUBSTANCE: charge for manufacture of aluminium-ferrous spinel, which contains an aluminium-containing component and an iron-containing component, also contains at least one alloying additive chosen from the following group: zirconium dioxide, titanium dioxide, at the following component ratio, wt %: aluminium-containing component - 56-65, iron-containing component - 35-44, alloying additive (over 100%) - 1-7.

EFFECT: creation of a heat-resistant refractory with a high flexible structure providing its integrity at high thermal and mechanical loads and having increased tendency to formation of a protective layer of lagging.

1 tbl

FIELD: metallurgy.

SUBSTANCE: invention relates to refractory ceramic mixture, as well as to refractory ceramic brick made therefrom, and can be used for lining of cement rotary furnaces. Refractory ceramic mixture has following composition: a) 75-98 wt%, at least main initial material from group: sintered magnesium oxide, magnesium oxide, b) oxide 2-25 wt% at least granular aggregate from group: silicon carbide, silicon nitride, silicon oxycarbide, silicon oxycarbonitride, c) maximum 5 wt% of other components, each time in terms of total mixture, main initial material is in range of 10-40 wt% in grinding fraction < 125 mcm, in terms of total mixture and granular aggregate is in granulometric fraction > 125 mcm and < 2 mm. Refractory ceramic brick made from said mixture by pressing and roasting is characterised by that in it granular aggregate maximum is half-sintered with main raw material.

EFFECT: technical result of invention is obtaining articles with fire resistance higher than 1,400 °C, high resistance to corrosion and effective structural elasticity.

12 cl, 3 ex, 2 tbl

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