RU2348595C2 - Method of fabrication of products from refractory mass (versions) - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: fabrication method of products from refractory mass with the composition, wt %: mullite corundum mix (MCM) 45-60, high alumina cement (HAC) having lost activity in part or in whole 18-26, liquid glass 20-24, hardener 2-6, includes blending of components, casting into forms, thermal treatment. Fabrication method of products from refractory mass with the composition, wt %: MCM 25-29, chrysatile salamander wool No5 8-13, said HAC 33-35, liquid glass 20-24, hardener 2-6, and, possibly, refractory clay 2-4, includes blending of the components, semidry gunning, and thermal treatment. Fabrication method of products from refractory mass with the composition, wt %: MCM 2-4, said salamander wool 15-20, said HAC 34-38, clay 2-4, liquid glass 20-25, hardener 2-6, includes blending of the components, casting into forms, thermal treatment. Fabrication method of products from refractory mass with the composition, wt %: ramming mixture 65-67, said HAC 21-23, water 10-12, includes components blending, packing into forms, thermal treatment. Fabrication method of products from refractory mass with the composition, wt %: "МКС" 73-76, HAC 7-8, said HAC 7-8, water 10-11, includes components blending, casting into forms, thermal treatment.

EFFECT: increased lining life, penetrability, absence of cracks, quick set and freezing, preservation of performance characteristics in high temperatures.

16 dwg, 5 ex

Description

The invention relates to the production of refractories and masses for lining elements of thermal aggregates of metallurgy, heat power engineering, chemistry and other industries and can be used for the manufacture of monolithic bulk lining to protect aggregates from the effects of high thermal, thermal and other loads.

Lining is one of the main elements for protecting thermal units from the damaging effects of high thermal and thermal loads, the abrasive effects of the flow of solid particles, and chemical effects during operation in aggressive environments.

The main reason for the failure of the lining is the occurrence of through cracks and pores. One of the factors in the formation of cracks is the presence of physically and chemically bound moisture, which increases porosity and reduces strength and, as a consequence, the lining resistance.

It is necessary to have a reliable mass for the manufacture of a lining with high durability and a long service life, which could be made and used in the conditions of the current production depending on the time the mass was ready for work, the place of its use, the aggressiveness of the environment and operating conditions.

Known compositions of solutions, refractory refractory concrete based on cement binders, sodium liquid glass, hardeners [I.A. Shishkov, A.A. Aizenberg, V.I. Belsky, etc. Construction of industrial furnaces. M., Stroyizdat, 1978, p. 64-85].

The disadvantage of such concrete is a significant increase or shrinkage at the maximum temperature of application, a predisposition to cracking, a relatively low temperature of application, a large loss of strength with increasing temperature.

A known method of manufacturing a mass for lining induction furnaces containing finely ground magnesite, chamotte powder, chamotte crushed stone, sodium liquid glass, sodium silicofluoride, alumina, high alumina cement (VHC) [USSR Author's Certificate No. 356266, IPC С04В 35/68, 10.23.1972 g .].

The disadvantage of a lining made by this method is its high wettability by liquid metal and its penetration into the pores and cracks of the lining, as well as significant volumetric shrinkage during drying, which leads to its significant delamination and shorten the life of the lining.

The closest in technical essence and the achieved results to the proposed invention is a method of manufacturing products from refractory mass, including mixing in wt.%: Electrocorundum fractions up to 7 mm - 36-69, high-alumina cement - 7-16, finely dispersed corundum - 14-24 , silicon carbide - 13-27 and plasticizing additives - 0.03-0.55, the addition of water, pouring into molds and hardening [RF Patent No. 2239612, IPC С04В 35/101, С04В 35/66, 10.11.2004].

The disadvantages of this method are the inability to use for fast manufacture and use of the mass and products from it in the conditions of the current production, associated with the length of time from the start of production to the end of solidification and obtaining the finished product.

The technical result of the invention is to increase the service life of the lining by increasing the strength and wear resistance of the refractory mass both during hardening in natural conditions and at high temperatures, the absence of shrinkage and growth during hardening at high temperatures, good penetration and absence of cracks, fast setting and hardening and the possibility of use in existing production at high temperatures in extreme situations while maintaining operational properties.

The technical result is achieved by the fact that in the method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components, casting the refractory mass into molds and solidification, according to the invention, high-alumina cement is used, which has completely or partially lost its activity - 18-26 wt.%, as a filler - mullite-corundum mixture 45-60 wt.%, as additives - water glass 20-24 wt.% and hardener 2-6 wt.%, and hardening is carried out by heat treatment Otke.

The technical result is also achieved by the fact that in the method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components and hardening, according to the invention, high-alumina cement is completely or partially lost its activity - 33-35 wt.%, As filler - mullite-corundum mixture 25-29 wt.%, as additives - liquid glass 20-24 wt.% and hardener 2-6 wt.%, after mixing, semi-dry shotcrete is carried out, and hardening is carried out at eplovoy processing.

The technical result is also achieved by the fact that in the method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components and hardening, according to the invention, high-alumina cement is used - completely or partially lost its activity - 33-35 wt.%, In as a filler - a mullite-corundum mixture of 25-29 wt.% and chrysotile asbestos No. 5 8-13 wt.%, as additives - refractory clay 2-4 wt.%, water glass 20-24 wt.% and hardener 2- 6 wt.%, After mixing wasp semi-dry shotcreting, and hardening during heat treatment.

The technical result is also achieved by the fact that in the method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components, casting the refractory mass into molds and solidification, the high-alumina cement is used according to the invention — completely or partially losing its activity 34-38 wt.%, as a filler - a mullite-corundum mixture 2-4 wt.%, chrysotile asbestos No. 5 15-20 wt.% and expanded clay 15-20 wt.%, as additives - refractory clay 2-4 wt.% liquid ste clo 20-25 wt.% and hardener 2-6 wt.%, and hardening is carried out during heat treatment.

The technical result is also achieved by the fact that in the method of manufacturing products from a refractory mass containing high-alumina cement and water, including mixing the components, placing the refractory mass in a mold and hardening, according to the invention, high-alumina cement is used, completely or partially lost its activity - 21-23 wt. %, an additional packing mass of 65-67 wt.%, water 10-12 wt.%, the refractory mass is placed in the mold by packing, and solidification during heat treatment.

The technical result is also achieved by the fact that in the method of manufacturing products from a refractory mass containing aggregate, high alumina cement, additive and water, including mixing the components, casting the refractory mass into molds and solidification, according to the invention, the mullite-corundum mixture 73- is used as a filler. 76 wt.% And as an additive - high alumina cement, fully or partially lost its activity of 7-8 wt.%, High alumina cement 7-8 wt.%, Water 10-11 wt.%, And hardening with heat rabotke.

The use of VGC-1 in the manufacture of refractory masses, which over time partially lost its activity under natural conditions, leads to the appearance of a triple effect: two simultaneously occurring processes and, over time, partial restoration of its previously lost activity.

The presence of temperature is one of the working conditions of such a composition.

Table 1 presents the physical and mechanical properties of the VHC-1 according to GOST 969-91.

Table 1 The compressive strength after 3 days, MPa Setting time Start, min End h 35.0 not earlier than 30 no later than 12

According to the invention, old high-alumina cement with a holding period of 8-12 months or more was tested in accordance with the technical standard for this type of cement to determine the loss or preservation of its original properties.

The addition of high alumina cement became such only after these tests.

The following is established.

- The beginning of the setting occurred 3 hours after mixing, the end of the setting - after 5 hours 50 minutes.

- The compressive strength in a day after mixing and holding in water could not be determined, because the dissolved mixture did not harden and, when the sample was removed, the beam broke.

The two remaining beams in metal form were placed in a steaming chamber and after heat treatment at 70 ° C were tested. The tensile strength averaged 40 MPa (40.78 kg / cm). Destructive phenomena are not noted. The compressive strength after three days of hardening in water is 49.5 MPa (504.1 kg / cm ² ). When aging samples - beams in natural conditions for one day, the set of strength did not occur. When touched by hands, the samples were destroyed.

Based on the foregoing, this cement has significant deviations in solidification time and curing in the first day and does not meet the operational requirements for this indicator.

As a result of the loss over time of its original qualities that cement had, it cannot be used for its intended purpose. By adding cement such as a finely ground additive to the proposed mass, which in itself is already refractory heat-resistant concrete with certain physical and mechanical properties, and we use it as a carrier of the cement additive, at the stage of manufacturing and delivery of the mass to the molds at the place of use, and then when it undergoes solidification processes occurring in a liquid binder with a hardener with the formation of hardened stone, we use it as a form in which the additive is made of cement, when the temperature is exposed to the form and the moisture-containing medium from moisture contained in the hardened stone, again acquires the properties of hydration and hydrolysis, intensifying the process of hydraulic solidification of cement with the restoration of its lost strength properties in natural conditions, enhancing the service physical and mechanical properties of the mass, which is (became) its carrier and form.

The chemical composition of the used VHC-1 is presented in table 2.

table 2 No. of sample, issue The content of element oxides,% Al ₂ O ₃ Fe ₂ O ₃ CaO High Alumina Cement 65.0 1.43 31.5

To assess the effect of VHC-1 on the properties of the refractory mass, namely, changes in the activity of cement until it was completely lost, they were monitored for several months, testing cement samples in full accordance with the scientific and technical documentation in order to identify their properties that were previously obtained when testing the VHC-1.

As a result of these tests, there is a tendency to lose its activity over time, the loss of strength in bending and compression under natural conditions.

So, the tests carried out at VHC-1 showed a decrease in cement activity from 21.0% and 16.9% to 100%, loss of compressive strength from 27.8 MPa and 29.1 MPa, to the absence of compressive strength in natural conditions.

The last sample was tested according to GOST 10178-85 ^* “Portland cement and slag Portland cement. Technical conditions. "

After steaming one day after mixing, the compressive strength was 29.4 MPa, after 28 days - 59.4 MPa.

Such cement can be used in production, taking into account the identified properties. At the same time, the chemical composition of the tested cement was investigated.

The chemical composition of the tested cement is presented in table 3.

Table 3 Material The content of element oxides,% Al ₂ About ₃ Fe ₂ O ₃ CaO High Alumina Cement (VHC-1) 66,4 0.73 21.5

Examples of using

Example 1

According to the invention, the additive from VHC-1, old cement with a holding period of 8-12 months or more, was subjected to tests to determine physical and mechanical properties. The following was established: the start of setting occurred 3 hours after mixing, the end of setting - after 5 hours 50 minutes, it was not possible to determine the compressive strength, because when stripping a sample, the beam broke. From which it follows that this cement completely lost its strength properties and cannot be used for its intended purpose.

This cement was used to prepare a refractory mass, which was used as a ceramic patch on the let of a blast furnace. The composition of the used masses are given in table 4.

Table 4 Composition number Mullite-corundum mixture,% VHC-1,% Liquid glass, % Hardener,% Sodium silicofluoride Ferro-slag one. 62.5 17 19 0.75 0.75 2. 60 eighteen twenty one one 3. 54 twenty 23 3 - four. 52,5 22 21.5 - four 5. 51 23 21 5 - 6. 47 25 22 3 3 7. 45 26 24 - 5 8. 41 27 25 3,5 3,5

The essence of the operation was as follows. The restoration of the partially burnt lining of the corolla, the filling and replacement of voids from the burnt metal frame of the notch were carried out in the conditions of an operating furnace, without stopping production. Patterns were made that repeated the contours of the frame of the taphole and the lining of the rim, and welded to the remains of the existing frame, and the space between the frame of the taphole and the casing of the furnace was sewn with a metal sheet to form a container that communicated with the frame of the taphole and the lining of the rim.

The prepared mass was poured into this container, which filled all the voids in the notch frame and the corolla lining with a penetration depth of about 700 mm along the burned notch frame. The poured tank becomes an additional ceramic protection for the tap hole and the furnace casing.

After the mass was set, the templates and the sheet were removed, the necessary operations were carried out to prepare the tap hole for work. Then, the seized mass was heated from the outside with a weak flame of a burner with a temperature not exceeding 70 ° C for 1-2 hours from the inside, from the side of the furnace casing, the heat of the furnace with a temperature of approximately 50 ° C was exposed to the ceramic patch.

Over time, the process of polymerization hardening of liquid glass with a hardener and the transition to an insoluble state with the formation of a bound space in the hardened mass occurs in the mass.

Further, in the process of penetration of the mass deep into the masonry of the hearth of the blast furnace, the temperature effect on it increases. Under the influence of temperature and a steam-humid environment that occurs both in the mass and around it, in the hardened mass, the process of hydraulic hardening of cement takes place. The compaction of the mass occurs due to the natural vibration of the blast furnace during its operation.

During hardening and during operation, the ceramic patch did not crack, did not collapse due to a change in the impact of mechanical shock on it, exposure to water and high temperature (1500 ° C), from liquid cast iron emanating from the tap hole.

Samples were taken from various parts of the ceramic lattice and samples were made to study the physicomechanical properties of the refractory mass. The test results are presented in table 5.

Table 5 Composition number Tensile strength, N / mm ² Open porosity,% The apparent density, g / cm ³ one. 26,50 24.4 1.97 2. 44.5 21.8 2.00 3. 42.5 22.2 1.99 four. 44.5 22.2 1.99 5. 56.4 22.0 2,34 6. 50.7 18.7 2,39 7. 52,4 23.6 2.20 8. 37.0 23,4 2,32

As can be seen from table 5, the use of VHC-1, which completely lost its activity under natural conditions, as part of the refractory mass (options 2-7) restores it, giving the mass high strength properties of the cement included in its composition.

According to the methodology for determining the restoration of cement activity at 70 ° C and exposure to a steam-humid environment, it follows that the samples with ultimate strength (N / mm ² ) of 50.7; 56.4; 44.5 were in the same conditions as cement when restoring their original properties.

Samples from the remaining samples from the ceramic lattice were sent for studies of physical and mechanical parameters when exposed to various temperature conditions. Two samples Ia, Ib and two samples IIIb, IIIc - made of ceramic lattice samples, were subjected to second drying at a temperature of 100 ° C and holding in a furnace for 32 hours, after which samples Ia and IIIb were removed from the furnace and went through a cooling process in vivo to room temperature, then tested for compressive strength. Samples Ib and IIIc were again dried and then fired in an oven to a temperature of 800 ° C at a rate of temperature rise of 75 ° C / h to 300 ° C; 120 ° C / hour to 800 ° C, and holding for 3 hours.

The properties of the samples were determined according to standard methods. All samples were subjected to various physical and mechanical tests. The test results are presented in table 6.

Table 6 Physico-thermal properties of the mass Sample Index The compressive strength of the sample after drying at T = 100 ± 5 ° C for 32 hours kgf / cm ² , R100 The compressive strength after firing at T = 800 ° C kgf / cm ² , R800 The residual tensile strength in compression R _ost ,% Exposure above water for 7 days after firing Ia 233.0 82.0 No cracks Ib 191.1 IIIb 334.8 89.6 No cracks IIIc 299.9

The residual tensile strength in compression was determined by the formula:

R _ost = (R800 / R100) 100%,

where R800 and R100 are the compressive strengths of samples, respectively, after heating to 800 ° C and dried at 100 ° C ± 5 ° C kgf / cm ² .

The test results are shown below:

R _ost ,% of samples:

Ia, Ib - 82; IIIb, IIIc - 89.57.

Studies have shown that the hardening process of ceramic lattice samples with tensile strengths of 50.7; 56.4; 44.5 N / mm ² passed within the temperature range of 70 ° C. Samples from ceramic latches, table 6, were dried, sample Ia - tensile strength 233.0 kgf / cm ² and IIIb - 334.0 kgf / cm ² , and roasting, sample Ib - ultimate strength 191.1 kgf / cm ² and IIIc - 299.9 kgf / cm ² . The results showed that a decrease in the tensile strength of such samples, the curing of which took place under the necessary conditions, after subsequent firing occurs slightly, without cracking.

To comparatively assess the effect of cement, which has completely lost its activity under natural conditions, on the physicomechanical properties of the mass, studies were carried out on the effect on the mass of various temperature loads, hot air flows at T = 1200 ° C, and the effect on the strength of direct and indirect effects of heat flow , the influence of lack of moisture and time on the formation of solidification processes: polymerization and hydration, what are the consequences of dehydration of the mass and direct exposure to an open flame and.

It follows from the studies that the introduction of cement into the composition of the cement with a complete loss of its activity in natural conditions and its presence in conditions that allow it to restore its activity led to the appearance of a double action effect - two processes occurring simultaneously: polymerisation hardening of resins is a manifestation of the hydration process, which:

- provide an increase in the strength of the masses in 1.5-2 times;

- contribute to an increase in its residual strength after heat treatment to 800 ° C;

- provide a reduction in residual moisture in the mass and exclude cracking both in vivo and at high temperatures.

However, the violation of the conditions for the restoration of VHC-1 activity, which includes holding the mass in the drying chamber at a temperature of 45 ° C or prolonged exposure to the burner flame immediately after curing, contributes to:

- removal of residual moisture from the mass, so necessary for the process of hydration of the additive from cement;

- decommissioning and transition of the VHC again to the category of cements;

leads:

- to the occurrence of only one process of polymerization hardening of resins;

- to reduce the strength properties;

- to transfer the refractory mass to the category of heavy heat-resistant concrete based on liquid glass.

The refractory masses of the proposed composition are used for filling the lining of hot-blast gates, parts of tuyere devices - nozzles, elbows, nozzles, pouring a ceramic cup inside an air lance or manufacturing for this purpose a ceramic insert of various cross-sections, pouring a corolla and a case on the blast-holes of a blast furnace, filling the gap between horn laying and letka, periodically restoration of the destroyed or worn linings of the lower sockets of gramophones, stuffed elbows, pipes with a bulk mass of short x blast furnace stops, apply it in extreme and emergency situations to replace burnt or destroyed linings or other elements of blast furnaces.

In the process of industrial testing and operation of the refractory mass, its properties such as:

- increased mobility;

- plasticity at the initial stages of preparation and subsequent work with it;

- workability, ability to flow and fill cracks, voids, etc .;

- the ability to regulate the hardening time;

- water tightness;

- reduction or absence of shrinkage with increasing temperature during hardening;

- good adhesion to metal surfaces;

- wear resistance;

- reduction of time spent on its use, in contrast to conventional lining methods;

- the possibility of using it in extreme and emergency situations.

Example 2

Recently, a refractory mass was used to solve the problems of protecting the casing of the blast furnace dome from constant heat loads, restoring the thermal protection lining of the very dome of the obturation of the mounting hatch and its lid.

The use of the masses of the claimed compounds was facilitated by the fact that the design thermal protection of the dome, consisting of MKRP-340 mullite-siliceous plates, a metal mesh with a layer of shotcrete on it based on alumina cement, fireclay powder, chrysotile asbestos No. 7, water - all it was additionally protected by stainless plates - it stood for only 2 years, and the fact that restoring design protection on a working furnace is a difficult task.

Two versions of shotcrete samples were made: five samples using refractory clay and six samples without it. The formation of the structure of which occurred both in vivo and under the influence of temperature for several days. The component composition of the samples is presented in table 7.

Table 7 Composition number Mullite-corundum mixture,% Asbestos chrysotile No. 5,% VHC-1,% Refractory clay,% Liquid glass,% Hardener,% Sodium silicofluoride Ferro-slag one. thirty fourteen 36 one eighteen one - 2. 29th 13 33 3 twenty - 2 3. 26 10 34 four 22 four - four. 25 8 35 2 24 3 3 5. 21 7 32 5 25 5 5 6. 31 7 37 - eighteen 7 - 7. 29th 8 35 - 22 6 - 8. 28 13 34 - twenty - 5 9. 25 12 33 - 24 3 3 10. 27 13 35 - 23 one one eleven. 24 fifteen 32 - 28 - one

Samples sent to the laboratory to determine the mechanical strength, porosity and apparent density. The results are presented in table 8.

Table 8 Composition number Tensile strength, N / mm ² Open porosity,% The apparent density, g / cm ³ one. 8.2 47.1 1,57 2. 9.5 46.3 1,58 3. 10.1 46.5 1,56 four. 9.8 46.8 1.55 5. 7.8 47.3 1,61 6. 13.9 42.1 1.78 7. 14.7 40.5 1,67 8. 15.1 40.1 1,63 9. 14.8 40,4 1.65 10. 14.9 40,2 1,62 eleven. 14.1 41.9 1.87

According to the results of the analysis of physical properties, and referring to the theory, it follows that the presence of asbestos in the mass with the addition of a solidification accelerator increases strength, increases the heat resistance and adhesive ability of heat-insulating materials, and the mullite-corundum mixture increases the compressive and bending strength properties.

Also, two metal plates with a coating layer of compositions 1, 3, 6, 10 were applied to the laboratory. Upon visual inspection, the masses of compositions 3, 10 have better adhesion to the metal surface than the masses of composition 1, 6.

Based on the foregoing, the masses of compositions 2-4 and 7-10 have the best service properties for the manufacture of shotcrete and can be used as a heat-insulating layer on the dome of the DP.

A mass of the proposed composition was deposited on a metal mesh mounted on a dome casing by a shotcrete machine of semi-dry shotcrete (TM-969). The proposed thermal insulation of the dome stood until the end of the blast furnace campaign number 5 without any repairs.

Example 3

Positive practical results obtained from the use of refractory masses on the basis of the proposed composition after partial replacement of the mullite-corundum mixture with expanded clay (fractions with a particle size of up to 20 mm with a bulk density of 500-650 kg / m ³ ) were used to fill stainless cassettes, of which consists of a lining furnace for the production of aluminum fluoride in a chemical plant.

The problem was solved of the urgent replacement of the existing lining of the furnace, consisting of perlite powder, filled in shells. She decided on the use of refractory masses, the component composition of which is given in table 9.

Suitability for use was decided in this way: the test mass cassettes were sealed hermetically and thrown into the oven at a temperature of 500 ° C in a wet state. The result was immediately apparent: the cassette with the proposed composition was slightly expanded, another cassette was torn apart.

When studying the properties of the mass, the compressive strength was taken as the main characteristic. The test results are presented in table 10.

Table 10 Physico-mechanical properties of the mass Composition number Tensile strength, N / mm ² one. 10.5 2. 13.6 3. 11,4 four. 12.8 5. 11.9 6. 10.1

The resistance of the lining of the refractory masses of the proposed composition, in contrast to the old, is much higher. The temperature of the furnace shell decreased by more than 100 ° C.

Table 9 Composition number Mullite-corundum mixture,% Asbestos chrysotile No. 5,% Expanded clay,% VHC-1,% Refractory clay,% Liquid glass, % Hardener,% Sodium silicofluoride Ferro-slag one. 5 fourteen 22 33 5 twenty 1,0 - 2. four fifteen twenty 34 3 twenty four - 3. 2 16 16 35 four 21 3 3 four. 2 twenty fifteen 38 2 21 one one 5. 3 16 17 34 2 25 - 3 5. 1,5 22 fourteen 40 1,5 19.5 - 1,5

Example 4

In the process of industrial testing of refractory masses with VHC-1, which completely or partially lost its activity, tests of samples closed on water were carried out on liquid glass from ready-made trough masses with the introduction of VHC-1 cement into them.

VHC-1, which completely or partially lost its activity, was added to the ready-made dry gutter mixture, was mixed again and water was added. The resulting mass was manually stuffed into molds, and then the finished samples were tested in the laboratory, subjected to heat and moisture treatment at t = 70 ° C, dried at t = 100 + 5 ° C for 48 hours, then fired at t = 800 ° C followed by exposure to water for 7 days. After that, tests were conducted to determine the tensile strength, density.

The composition of the studied refractory masses is presented in table 11.

Table 11 Composition number Stacked mass,% VHC-2 with plasticizer,% Additive from VHC-1,% Water% one 65 23 - 12 2 66 23 - eleven 3 67 21 - 12 four 67 23 - 10 5 65 - 23 12 6 66 - 23 eleven 7 67 - 21 12 8 67 - 23 10

The composition of the packed masses is presented in table 12.

Table 12 Composition number The composition of the stuffed mass Ground clay,% Fireclay powder,% High alumina powder,% Silicon carbide (sludge),% Ground coke,% High-temperature pitch,% 1, 2, 3, 4 35.5 21.0 - - 29th 14.5 5, 6, 7, 8 22 - fifteen 23 thirty 10

The test results are presented in table 13.

Table 13 No. sost ava Sample label Heat and humidity treatment at t = 70 ° С Drying at t = 100 + 5 ° C for 48 hours Firing at t = 800 ° С followed by exposure to water for 7 days Density, g / cm ³ Tensile strength, kgf / cm ² one I VHC-2 + 1,826 182.8 2 + + 1,743 251.2 3 + + + 1,630 171.8 four + + 1,599 216.6 5 II VHC-1 + 1,913 207.5 6 + + 1,826 329.0 7 + + + 1,589 182.58 8 + + 1,571 231.6

The data in table 13 show that the samples from the stuffed mass with the additives added to them: I-VGTs-2 with a plasticizer, II-VHTs-1, which completely lost their activity in vivo, provide high strength and density indicators, and no cracks after aging over water, allow the mass to be dried without heat and moisture treatment.

These indicators exceed the test results of the own groove and sheath mass, which include: mullite-corundum mixture, refractory clay, silicon carbide, pitch, coke.

Tests in the laboratory of control samples of the gutter and case masses after calcination showed the following physical and mechanical properties:

Tensile strength N / mm ² Density g / cm ³ Gutter mass 5.1-5.5 1.62-1.76 Case mass 6.9 -

The masses made with VGTs-1 (compositions No. 5-8) have significantly better physical and mechanical properties.

Example 5

At the same time, samples of bulk water based on a mineral binder were manufactured, researched, and passed industrial tests.

A dry mixture was prepared from the mullite-corundum mixture, VHC-1 cement fresh 50%, it was additionally supplemented with old VHC-1 cement, which had lost its activity under natural conditions, but 50% of the required amount, water was added and everything was mixed. The resulting mass was poured into molds, and then the prepared hardened samples were subjected to laboratory tests using the same system as the packed masses.

The mass composition and test results are presented in tables 14 and 15, respectively.

Table 14 Composition number Mullite-corundum mixture,% VHC-1,% Additive from VHC-1,% Water% one 73 8 8 eleven 2 74 8 7 eleven 3 75 7 8 10 four 76 7 7 10

Table 15 Composition number Heat and humidity treatment at t = 70 ° C Drying at t = 100 + 5 ° C for 48 hours Firing at t = 800 ° C followed by exposure to water for 7 days Tensile strength kgf / cm ² Cracks one + + + 443 - 2 + + + 565 - 3 + + + 504 - four + + + 507 -

The data in table 15 show that the refractory mass based on a mineral binder with a 50% addition of VHC-1 provides high tensile strength and the absence of cracks after exposure to water.

Refractory masses based on a mineral binder, with 50% of the required additive from high-alumina cement, with the loss of their properties, were used as linings in special nozzles used to blow dust-containing substances - schungite, rutelite - into a blast furnace.

Samples made from these masses were tested in the laboratory. The data from these tests are presented in table 16.

Table 16 No. p / p Sample label Heat and humidity treatment at t = 70 ° С Drying at t = 100 + 5 ° C for 48 hours Firing at t = 800 ° С followed by exposure to water for 7 days Density, kg / m ² Tensile strength, kgf / cm ² one I + 2340 276.8 2 + + 2330 263.6 3 + + + 2165 229.7 four II + 2463 430.9 5 + + 2425 524.5 6 + + + 2307 508.1 7 + + 2161 434.4

Two different bulk compositions were investigated:

I - mullite-corundum mixture; but 50% of the required amount of VHC-1 cement fresh and additives from VHC-2 with old plasticizer, water;

II - mullite-corundum mixture; but 50% of the required amount of VHC-1 cement fresh and additives from VHC-1 old, water.

The data in table 15 show that samples of a refractory mass based on a mineral binder with the addition of 50% cement, which has lost its activity under natural conditions, provide high strength and density at different temperatures, the absence of cracks after exposure to water, and the ability to dry the mass without significant loss of properties.

However, the use of cement VGC-2 as a cement additive with a plasticized additive reduces the service properties of the mass.

The proposed refractory masses belong to the category of liquid bulk and make it possible to obtain refractory products of complex configuration with minimal capital and labor costs.

The proposed methods for the manufacture of refractory masses working in contact with liquid metals will increase the service life of products, their performance, reduce costs and increase the manufacturability of the production process of refractory masses.

Information sources

1. I.A. Shishkov, A.A. Aizenberg, V.I. Belsky et al. Construction of industrial furnaces. M., Stroyizdat, 1978, p. 64-85.

2. USSR author's certificate No. 356266, IPC С04В 35/68, 10.23.1972

3. RF patent No. 2239612, IPC С04В 35/101, СВВ 35/66, 10.11.2004.

Claims (6)

1. A method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components, casting the refractory mass into molds and solidification, characterized in that they use high-alumina cement - completely or partially lost its activity, as a filler - mullite corundum mixture, as additives - water glass and hardener in the following ratio of components, wt.%:
Mullite-corundum mixture 45-60 High alumina cement, partially or completely lost its activity 18-26 Liquid glass 20-24 Hardener 2-6,
and solidification is carried out by heat treatment. 2. A method of manufacturing products from a refractory mass containing high alumina cement, aggregate and additives, including mixing the components and hardening, characterized in that they use high alumina cement - completely or partially lost its activity, as a filler - mullite-corundum mixture and chrysotile asbestos No. 5, as additives - liquid glass and hardener in the following ratio of components, wt.%:
Mullite-corundum mixture 25-29 Asbestos chrysotile No. 5 8-13 High alumina cement, completely or partially lost its activity 33-35 Liquid glass 20-24 Hardener 2-6,
after mixing the components, semi-dry shotcrete is carried out, and solidification during heat treatment. 3. A method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components and solidification, characterized in that they use high-alumina cement - completely or partially lost its activity, as a filler - mullite-corundum mixture and chrysotile asbestos No. 5, as additives - refractory clay, water glass and hardener in the following ratio of components, wt.%:
Mullite-corundum mixture 25-29 High alumina cement, partially or completely lost its activity 33-35 Asbestos chrysotile No. 5 8-13 Fire-clay 2-4 Liquid glass 20-24 Hardener 2-6,
after mixing the components, semi-dry shotcrete is carried out, and solidification during heat treatment. 4. A method of manufacturing products from a refractory mass containing high-alumina cement, aggregate and additives, including mixing the components, casting the refractory mass into molds and hardening, characterized in that they use high-alumina cement - completely or partially lost its activity, as a filler - mullite - corundum mixture, chrysotile asbestos No. 5 and expanded clay, clay, water glass and hardener as additives in the following ratio of components, wt.%:
Mullite-corundum mixture 2-4 Asbestos chrysotile No. 5 15-20 Expanded clay 15-20 High alumina cement, completely or partially lost its activity, 34-38 Clay 2-4 Liquid glass 20-25 Hardener 2-6,
and solidification is carried out by heat treatment. 5. A method of manufacturing products from a refractory mass containing high-alumina cement and water, comprising mixing the components, placing the refractory mass in a mold and hardening, characterized in that high-alumina cement is used, which has completely or partially lost its activity, and additionally, the packed mass in the following ratio of components , wt.%:
Ram mass 65-67 High alumina cement, completely or partially lost its activity 21-23 Water 10-12,
placement of the refractory mass into the mold is carried out by stuffing, and solidification during heat treatment. 6. A method of manufacturing products from a refractory mass containing aggregate, high alumina cement, an additive and water, including mixing the components, casting the refractory mass into molds and solidification, characterized in that the mullite-corundum mixture is used as a filler and high alumina cement is used as an additive , fully or partially lost its activity, in the following ratio of components, wt.%:
Mullite-corundum mixture 73-76 High Alumina Cement 7-8 High alumina cement, completely or partially lost its activity 7-8 Water 10-11,
and solidification is carried out by heat treatment.