JP2005314222A - Heat insulating castable refractory for pump pressure feeding and wet spray working method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat insulating castable refractory for pump pressure feeding which is formed into a worked body having excellent heat insulation and fire resistance without causing clogging trouble of a pipe line by the separation of aggregate from a matrix in the pump pressure feeding with respect to a heat insulating castable refractory containing the lightweight refractory aggregate, and a wet spray working method capable of remarkably reducing the construction period without necessitating a complicated step such as a form laying work by using the heat insulating castable refractory for pump pressure feeding. <P>SOLUTION: The heat insulating castable refractory for pump pressure feeding is prepared by kneading a refractory composition comprising lightweight refractory aggregate having bulk density of ≤1.0, refractory fine powder having ≤75 μm average particle diameter and alumina cement and a separation preventing agent with water. The blending ratio of the volume of the lightweight refractory aggregate to the volume in total of the refractory fine powder and the alumina cement is 0.65-0.85. The wet spray working method is carried out by pressure-feeding the insulating castable refractory by the pump while adding a quick setting agent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat-insulating castable refractory for pumping used for coating of lining materials of atmosphere furnaces such as a slab heating furnace and a soaking furnace, heat-resistant members such as skid pipes and posts, and a wet spraying method thereof About.

A refractory for a heat-resistant member of an atmosphere furnace such as a billet furnace or a soaking furnace is required to have high fire resistance and excellent heat insulation. Conventionally, what contains a ceramic fiber is used as a castable refractory having high fire resistance and high heat insulation. In JP-A-6-87666, the main component is Al ₂ O ₃ · SiO ₂ refractory material, and 5 to 20% by weight of ceramic fiber granular cotton having a pulverized particle size of 10 to 50 mm is added to 100% by weight. On the other hand, a heat insulating castable to which 0.1 to 0.5% by weight of a foaming agent is added is disclosed. Japanese Patent Application Laid-Open No. 7-69743 contains alumina-based refractory aggregate and / or mullite-based refractory aggregate, hydraulic intermediate alumina, foam, ceramic fiber, and microsilica. An insulating castable is disclosed. Insulating castable refractories containing ceramic fibers have not only excellent heat insulation but also high fire resistance, and can be used in high temperature environments close to 1500 ° C.

  However, the heat-insulating castable refractory containing ceramic fibers has a problem that the ceramic fiber is scattered and suspended in the atmosphere in a large amount during mixing to deteriorate the construction environment, and also has an economic difficulty of being expensive.

Therefore, in recent years, heat-insulating castable refractories having high heat insulating properties and high fire resistance without containing ceramic fibers have been developed, and some of them have been put into practical use. Japanese Patent Laid-Open No. 2003-002754 (Patent Document 1) has an Al ₂ O ₃ content of 90% by mass or more, a bulk specific gravity of 0.6 to 0.8, a pore diameter of 5 μm or less, and an open pore of 50% by volume or more (as a whole pore) Insulating castable refractories using 70% by volume or more lightweight alumina as the main aggregate and alumina cement as the binder are disclosed. This heat-insulating castable refractory is described as being applied by means of pouring, press-fitting, spraying, and the like after being kneaded together with about 50 to 60% by mass of construction water on the outside. In general, a paste-like portion (hereinafter referred to as a matrix portion) composed of a binder such as alumina cement and water has a large specific gravity. Therefore, when kneaded together with an aggregate having a small specific gravity, the aggregate is separated. It is likely to occur. On the other hand, when a lightweight alumina having an open pore of 50% by volume or more is used as in Patent Document 1 and the amount of construction water is about 50 to 60% by mass, the separation can be prevented to some extent.

  However, as a result of the study by the present inventors, in the heat insulating castable refractory described in Patent Document 1, the ease of separation of lightweight alumina is not problematic for pouring work, but it is used for spraying etc. It was found that separation prevention was not sufficient for pumping. In particular, when constructing as a covering material for a skid pipe, the work of framing the skid pipe is very complicated, and if the pump cannot be pumped, the work process will be greatly delayed.

  Insulated castable refractories are generally kneaded using a mixer at the construction site, but when installing in a slab heating furnace or soaking furnace, the furnace at the construction site is narrow, so bring in a mixer. It is difficult. For this reason, it is necessary to transport the material once kneaded outside the furnace to the construction site. Since it takes a lot of work labor to transport the kneaded material manually by a bucket relay or the like, it is preferable to transport it using a pressure pump and a pressure piping. However, in the case of containing a refractory aggregate having a small specific gravity, such as the heat-insulating castable refractory described in Patent Document 1, the lightweight refractory aggregate is separated from the matrix portion by pressurization in the pumping pump and the piping for pumping. There is a problem that it is easy. If the lightweight refractory aggregate segregates in the material due to the separation, the fluidity of the material is lowered, resulting in a blockage trouble in the piping for pressure feeding.

JP 2003-002754 A

Accordingly, an object of the present invention is to provide excellent heat insulation and fire resistance in a heat-instable castable refractory containing light-weight fire-resistant aggregate, without causing troubles in piping due to separation of the aggregate from the matrix portion during pumping. It is providing the heat insulation castable refractory material for pump pumping used as the construction body which has.
Another object of the present invention is to provide a wet spraying method capable of drastically shortening the construction period without using a complicated process such as a frame work by using the heat insulating castable refractory for pumping. That is.

  As a result of diligent research in view of the above object, the present inventors have made the pump by using a special gum as an anti-separation agent while keeping the volume ratio of the lightweight refractory aggregate to the refractory composition within a specific range. Insulating castable refractories for pumping that are unlikely to cause clogging problems due to material separation during pumping are obtained, and using such heat insulating castable refractories for pumping, wet with adding a caking agent together with compressed air at the spray nozzle When sprayed, it was discovered that a complex-shaped construction body could be obtained without a formwork, and the present invention was completed.

  That is, the heat-insulating castable refractory for pumping according to the present invention comprises a lightweight refractory aggregate having a bulk specific gravity of 1.0 or less, a refractory composition comprising a fire-resistant fine powder having an average particle size of 75 μm or less, and an alumina cement, and an antiseparation agent in water. The volume ratio of the lightweight refractory aggregate to the total of the lightweight refractory aggregate, the refractory fine powder, and the alumina cement is 0.65 to 0.85.

The separation inhibitor is preferably welan gum and / or xanthan gum. Moreover, it is preferable that the addition amount of a separation inhibitor is 0.01 to 0.1% by mass (external ratio) with respect to 100% by mass of the refractory composition. As a light-weight fire-resistant aggregate, a CaO · 6Al ₂ O ₃ composition or an Al ₂ O ₃ composition is preferable, a CaO · 6Al ₂ O ₃ composition is porous or an Al ₂ O ₃ composition is more hollow preferable.

  The amount of water for kneading the refractory composition and the separation preventing agent is preferably 35% by mass or more (outside ratio) with respect to 100% by mass of the refractory composition. The heat insulating castable refractory for pumping preferably has a flow value of 200 mm or more and a V funnel flow time of 60 seconds or less.

  The wet spraying method for heat-insulating castable refractories for pumping according to the present invention comprises a lightweight refractory aggregate having a bulk specific gravity of 1.0 or less, a refractory composition comprising a refractory fine powder having an average particle size of 75 μm or less, and alumina cement, and prevention of separation. The heat-insulating castable refractory for pumping obtained is kneaded with water, transported to the spray nozzle using the pump and the piping for pumping, and sprayed with the compressed air and the quick setting agent. The volume mixing ratio of the lightweight refractory aggregate to the total of the refractory aggregate, the refractory fine powder, and the alumina cement is 0.65 to 0.85.

It is preferable to use welan gum and / or xanthan gum as the separation inhibitor. The addition amount of the separation inhibitor is preferably 0.01 to 0.1% by mass (external ratio) with respect to 100% by mass of the refractory composition. It is preferable to use a CaO · 6Al ₂ O ₃ composition or an Al ₂ O ₃ composition as a lightweight refractory aggregate, a porous one with a CaO · 6Al ₂ O ₃ composition or a hollow one with an Al ₂ O ₃ composition It is more preferable to use one.

  The amount of water added is preferably 35% by mass or more (external ratio) with respect to 100% by mass of the refractory composition. It is preferable that the flow value of the heat insulating castable refractory for pumping is 200 mm or more, and the V funnel flow time is 60 seconds or less. The addition amount of the quick setting agent is preferably 0.1 to 3.0% by mass in terms of solid content with respect to 100% by mass of the refractory composition.

  The heat-insulating castable refractory for pumping of the present invention is obtained by kneading a refractory composition and an anti-separation agent with water, and contains a lightweight refractory aggregate having a bulk specific gravity of 1.0 or less in a volume mixing ratio of 0.65 to 0.85. To do. For this reason, in addition to having excellent heat insulation and fire resistance, it has the property that it is difficult to cause aggregate separation from the matrix portion by pumping. Therefore, it is difficult to cause a piping blockage trouble due to pumping during construction.

  The wet spraying method for heat-insulating castable refractories for pumping according to the present invention uses a heat-insulating castable refractory having excellent pumping ability and sprays it together with a rapid setting agent. According to this method, a heat-insulating castable refractory having excellent heat insulation and fire resistance can be obtained without requiring a complicated process such as frame work. For this reason, the construction period can be greatly shortened.

(A) Heat-insulating castable refractory for pumping The heat-insulating castable refractory for pumping according to the present invention comprises a light-weight refractory aggregate having a bulk specific gravity of 1.0 or less, an alumina cement, and a refractory fine powder having an average particle size of 75 μm or less. An anti-separation agent and water are added to the product and kneaded so that sufficient workability is obtained.

(A-1) Refractory composition
(A-1-1) Lightweight refractory aggregate The light weight refractory aggregate used in the present invention has a bulk specific gravity of 1.0 or less. A heat-insulating castable refractory for pumping containing a lightweight refractory aggregate having a bulk specific gravity of 1.0 or less exhibits excellent heat insulation and fire resistance. If bulk specific gravity is in this range, the structure will not be specifically limited. For example, any of porous, hollow and a mixture thereof may be used. The preferred bulk specific gravity of the lightweight refractory aggregate is 0.75 or less.

  The particle size of the lightweight refractory aggregate is preferably 5 mm or less, and more preferably 3 mm or less. A lightweight refractory aggregate having a particle size of more than 5 mm is not preferred because it tends to cause material separation by contact between the aggregates in the piping for pressure feeding. Practically, it is preferable to use a particle having a particle size of 5 mm or less as appropriate.

The composition of the lightweight refractory aggregate is not particularly limited as long as the effects of the present invention are not impaired, but 90% by mass or more of the lightweight refractory aggregate is preferably Al ₂ O ₃ (alumina). When 90% by mass or more of the lightweight refractory aggregate is Al ₂ O ₃ , a refractory composition that can be used even in a high temperature environment close to 1500 ° C. can be produced. One of the preferred forms of the lightweight refractory aggregate is a porous lightweight refractory aggregate composed of a CaO · 6Al ₂ O ₃ composition. A specific example of a preferable lightweight fireproof aggregate is “SLA-92” manufactured by Alcoa. Table 1 shows the composition and bulk specific gravity of “SLA-92” manufactured by Alcoa.

Another example of a preferred lightweight refractory aggregate is a hollow one having an Al ₂ O ₃ composition. A specific example is Bubble Morundum (registered trademark) manufactured by Showa Denko KK. Table 2 shows the composition and bulk specific gravity of Bubble Morundum (registered trademark).

(A-1-2) Alumina cement The alumina cement to be blended in the refractory composition is not particularly limited, and general ones can be used. Preferred alumina cements include those of JIS Class 1, 2 and 3 classes. By using these, the construction body of the heat insulation castable refractory which has high fire resistance, high curing strength, and high temperature strength can be obtained.

  The content of the alumina cement is preferably 5 to 10% by mass in terms of CaO with respect to 100% by mass of the refractory composition. If it is less than 5% by mass, the strength of the resulting construction is too low, and if it exceeds 10% by mass, the castable refractory will condense.

(A-1-3) Refractory fine powder The refractory fine powder used in the present invention has an average particle diameter of 75 μm or less, preferably an average particle diameter of 30 μm or less. If the average particle size exceeds 75 μm, fluidity suitable for pumping cannot be obtained. The type of refractory fine powder is not particularly limited as long as the effects of the present invention are not impaired, but it is preferable to use alumina fine powder such as electrofused alumina, sintered alumina or calcined alumina. By using alumina fine powder, the fire resistance and strength of the resulting construction can be improved.

(A-1-4) Volumetric mixing ratio of lightweight fireproof aggregate In the heat insulating castable refractory for pumping of the present invention, lightweight fireproof aggregate (volume V ₁ ) and fireproof fine powder (volume V ₂ ) It is important that the volume ratio of the lightweight refractory aggregate to the total (V ₁ + V ₂ + V ₃ ) of alumina cement (volume V ₃ ) is in the range of 0.65 to 0.85. The volume ratio r of the lightweight refractory aggregate is given by the following formula (1)
r = V ₁ / (V ₁ + V ₂ + V ₃ ) (1)
(In the formula (1), V ₁ represents the volume of the lightweight refractory aggregate, V ₂ represents the volume of the refractory fine powder, and V ₃ represents the volume of the alumina cement).

  In the present specification, the volume of the lightweight refractory aggregate, the refractory fine powder and the alumina cement represents the “apparent volume”. The “apparent volume” of the lightweight refractory aggregate is determined by dividing the mass of the lightweight refractory aggregate by its bulk specific gravity. The “apparent volume” of the refractory fine powder and alumina cement is determined by dividing its mass by the apparent specific gravity.

  If the volume ratio of the light weight fireproof aggregate is less than 0.65, the relative amount of the light weight fireproof aggregate is too small. When the volume ratio is larger than 0.85, the relative proportion of the lightweight refractory aggregate is too large, and the material is separated by contact between the aggregates, which is not preferable. A more preferable volume blending ratio is 0.7 to 0.8.

(A-2) Separation inhibitor The separation inhibitor used in the present invention is water-soluble, and increases the viscosity of the aqueous solution when dissolved. For this reason, when the separation preventing agent is contained, the fluidity of the heat insulating castable refractory for pumping does not become too low. Therefore, the anti-separation agent (a) prevents the separation of the lightweight refractory aggregate from the matrix part, and (b) suppresses the water absorption of the lightweight refractory aggregate due to pump pressurization, and ensures stable fluidity. The effect is obtained. Conventionally, water-soluble polymers have been widely known as anti-separation agents having such effects.

  Welan gum and / or xanthan gum is preferred as the separation inhibitor used in the heat insulating castable refractory for pumping of the present invention. Welan gum and xanthan gum are microbial fermentation polysaccharides, and in addition to the above-mentioned effects, (c) Compared with other antiseparation agents, there is less pressure loss in the piping due to increased viscosity of water. Also have.

  The addition amount of the separation inhibitor is preferably 0.01 to 0.1% by mass (external ratio) with respect to 100% by mass of the refractory composition. When the addition amount is less than 0.01% by mass, a sufficient separation preventing effect cannot be obtained. Addition exceeding 0.1% by mass is not preferable because the viscosity of the material becomes too high and the pressure loss in the pipe becomes too high.

(A-3) Water The amount of water added is preferably 35% by mass or more with respect to 100% by mass of the refractory composition. When the amount of added water is less than 35% by mass, it is impossible to obtain a sufficiently heat-insulated construction. A more preferable amount of added water is 40 to 130% by mass, and a particularly preferable amount of added water is 50 to 90% by mass.

(A-4) Pump pumpability As a problem in pumping heat-insulated castable refractories containing lightweight refractory aggregate,
(1) Easy to separate lightweight refractory aggregate and matrix (including water in some cases),
(2) Light pressure fire-resistant aggregate absorbs water by pressurizing during pumping, free water decreases, and fluidity deteriorates.
The thing is mentioned. Separation of lightweight refractory aggregate and matrix part (a) When the material is left in a hopper, it is caused by the difference in specific gravity of the aggregate and matrix part (and water), and (b) When pumping In addition, the aggregate is likely to be accumulated in the central portion of the pipe, and the matrix portion may be caused by a difference in fluidity that is easily accumulated in the peripheral portion of the pipe. The object of the present invention is mainly to solve the above-mentioned problem (1).

The present inventors have studied to find a simple table test method for evaluating pumpability, and found that the following method is effective.
(1) Measure the flow value measured according to JIS R 2521. However, the flow value after leaving for 3 minutes in a vibration-free state is adopted without performing 15 drop motions.
(2) Using the V funnel test machine schematically shown in FIG. 1, measure the material flow time (hereinafter simply referred to as “V funnel flow time”). Specifically, with the lid 3 at the lower end opening 2, the material is put into the V funnel tester from the upper end opening 1, and the inside of the testing machine is filled with the material, then the lid 3 is removed and the material from the lower end opening 2. The time required for all the material to flow out from the lower end opening 2 is measured. The size of the V funnel tester is as follows: upper end opening 1:30 x 270 mm, lower end opening 2:30 x 30 mm, length from upper end opening to straight barrel A: 240 mm, length of straight barrel B: 60 mm.

  The flow value reflects the dispersibility of the material and is an indicator of self-fluidity. A larger flow value means better pumpability. The V funnel flow time represents fluidity with gravity as the driving force, and is an index reflecting the separability of materials. The shorter the V funnel flow time, the better the pumpability.

  The heat insulating castable refractory for pumping preferably has a flow value of 200 mm or more and a V funnel flow time of 60 seconds or less. In this specification, “V funnel flow-down time” means the flow time of material using a V funnel tester. If the flow value is less than 200 mm or the V funnel flow time exceeds 60 seconds, good pumpability cannot be obtained.

(A-5) Other components The heat-insulating castable refractory for pumping of the present invention may contain other components in addition to the above-described components as long as the effects of the invention are not impaired. Other components are not particularly limited, and general components can be used as an additive for the heat-insulating castable refractory. Examples thereof include a dispersant, a usable / curing modifier, and a foam material.

(B) Wet spraying method for heat insulating castable refractories for pumping
(B-1) Spraying device FIG. 2 shows an example of a spraying device used in the wet spraying method of the present invention. The spraying device shown in FIG. 2 includes a pumping pump 4, a pumping pipe 5 connected to the pumping pump 4, and a spraying nozzle 6 attached to the tip of the pumping pipe 5 via a quick setting agent injector 7. Consists of. The quick setting agent injector 7 is configured to send the quick setting agent together with the compressed air from the metering pump 8 and the compressor 9.

  It is preferable that the pressure-feeding pipe 5 is made of metal because the pump-pumped heat-insulating castable refractory C is difficult to separate in the middle and easily reaches the spray nozzle 6 in a uniformly mixed state. However, for example, in a narrow construction site such as in a heating furnace, it is preferable to partially use rubber and / or synthetic resin in terms of piping. When using rubber and / or synthetic resin pumping pipe 5, the total extension distance (total length of rubber pipe and / or synthetic resin pipe) is 60 m, depending on the construction site conditions. Is preferred.

  The quick setting agent injector 7 is not particularly limited as long as the quick setting agent can be injected into the heat insulating castable refractory C for pumping that has reached the spray nozzle 6. For example, the one having a ring having about 8 to 16 holes (or slits) (so-called nozzle body) may be used. The nozzle body is generally used for dry spraying, and is connected to a nozzle and used for water injection.

As the metering pump 8, a multiple pulsating plunger pump or a Mono pump is preferable, and a multiple pulsating plunger pump is more preferable. High pressure injection is possible by using a multiple pulsating plunger pump. The injection pressure of the metering pump is preferably 5 kgf / cm ² or more.

  The pumping heat insulation castable refractory C is supplied to the pumping pump 4, and the inside of the pumping pipe 5 is pumped to the spray nozzle 6. The spray nozzle 6 is also supplied with the quick-setting agent by the metering pump 8 and the quick-setting agent injector 7, so that it is sprayed with the compressed air while adding the quick-setting agent to the heat-insulating castable refractory C for pumping. The nozzle 6 can be sprayed onto the work surface F.

(B-2) Quick setting agent It is preferable that the quick setting agent instantly retains the heat insulating castable refractory C for pumping and adheres it to the work surface F. By adding such a quick setting agent, it is possible to prevent the heat insulating castable refractory C from flowing on the work surface F. The form of the quick setting agent is not particularly limited, and a powder form or a solution form can be used.

  Examples of the quick setting agent include aluminate, carbonate, water used in the wet spraying method for dense cast refractories with low water content described in JP-A-9-25175 and JP-A-9-315872 Examples include calcium oxide and silicate. Among them, alkali silicate solutions such as lithium silicate, potassium silicate, and sodium silicate have an excellent shape retaining property and adhesiveness.

  Inorganic flocculants and organic flocculants (including polymers) used in fields such as wastewater treatment technology can also be used as quick setting agents for the heat-insulating castable refractory C. Inorganic flocculants and organic flocculants can also give excellent shape retention to heat-insulating castable refractories containing a large amount of moisture. Examples of preferred flocculants include metal salts of synthetic polymers such as polyacrylates and polyacrylamides, metal salts of natural polymers such as pectin and alginic acid, silica sols, and superabsorbent resins. Of these, sodium alginate is particularly preferable because it has an excellent effect of imparting shape retention.

  The addition amount of the quick setting agent is preferably 0.1 to 3.0% by mass in terms of solid content with respect to 100% by mass of the refractory composition. If it is less than 0.1% by mass, the shape retention effect is too small to sufficiently prevent the heat-insulating castable refractory C from flowing. Addition exceeding 3.0% by mass is not preferable because the alkali component is excessively increased and the fire resistance is excessively lowered.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Examples 1-6, Comparative Examples 1-4
Use porous aggregate (bulk specific gravity 0.65) of CaO.6Al ₂ O ₃ composition as light-weight fireproof aggregate or hollow aggregate (bulk specific gravity 0.68) of Al ₂ O ₃ composition, and CaO · Al ₂ as alumina cement Using JIS Class 2 equivalent (apparent specific gravity 2.95) containing O ₃ (60% by mass) and CaO · 2Al ₂ O ₃ (40% by mass), and containing 29.8% Al ₂ O ₃ as refractory fine powder A heat-insulating castable refractory was prepared using the calcined alumina fine powder (apparent specific gravity 3.98) at the blending ratio shown in Table 3. The bulk specific gravity of the lightweight refractory aggregate, the apparent specific gravity of the refractory fine powder and the alumina cement, and the volume mixing ratio r of the lightweight refractory aggregate were determined as shown below.

Bulk specific gravity of lightweight refractory aggregate: Measured according to JIS R 2205.
Apparent specific gravity of refractory fine powder and alumina cement: Measured by a liquid infiltration method using a pycnometer.
Volume ratio r of lightweight refractory aggregate to refractory composition: r (2)

(In the formula (2), M ₁ represents the mass of the lightweight refractory aggregate, d ₁ represents the bulk specific gravity of the lightweight refractory aggregate, M ₂ represents the mass of the refractory fine powder, and d ₂ represents the fire resistance. The apparent specific gravity of the fine powder was shown, M ₃ represents the mass of the alumina cement, and d ₃ represents the apparent specific gravity of the alumina cement.

  As shown in Table 3, it was found that the heat insulating castable refractory for pumping according to the present invention in which the volume mixing ratio of the lightweight refractory aggregate is 0.65 to 0.85 exhibits excellent heat insulating properties. It also had a preferred flow value and V funnel down time. On the other hand, Comparative Examples 1 and 3, which are less than 0.65 in volume ratio of the lightweight refractory aggregate, were inferior in heat insulation. Further, Comparative Examples 2 and 4 having a volume blending ratio exceeding 0.85 were inferior in fluidity.

Examples 7 and 8, Comparative Example 5
A heat-insulating castable refractory was produced in the same manner as in Examples 1 to 6 except that each component was blended so as to have the composition shown in Table 4. The resulting heat-insulated castable refractory was wet-sprayed while adding a lithium silicate solution as a quick setting agent, and the state of blockage of the pump and the piping for pressure feeding was observed.

  Examples 7 and 8 were capable of being pumped without causing clogging, and good sprayed constructions were obtained. On the other hand, in Comparative Example 5, the lightweight refractory aggregate separated during pumping, resulting in clogging in the piping. For this reason, the heat insulation castable refractory did not reach the nozzle and could not be sprayed.

It is the schematic which shows the structure of V funnel testing machine. It is the schematic which shows an example of the spraying apparatus used for the wet spraying construction method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Upper end opening part 2 ... Lower end opening part 3 ... Cover 4 ... Pressure feed pump 5 ... Pressure feed pipe 6 ... Spray nozzle 7 ... Quick setting agent injector 8 ..Quantitative pump 9 ... Compressor

Claims (13)

  It is a heat-resistant castable refractory for pumping pumps, which is made by mixing a fire-resistant composition composed of a lightweight refractory aggregate with a bulk specific gravity of 1.0 or less, a refractory fine powder with an average particle size of 75 μm or less and alumina cement, and an anti-separation agent with water. A heat-resistant castable refractory for pumping, characterized in that the light-weight fire-resistant aggregate, the fire-resistant fine powder, and the volume ratio of the light-weight fire-resistant aggregate to the total of the alumina cement is 0.65 to 0.85. .   The heat-insulating castable refractory for pump feeding according to claim 1, wherein the anti-separation agent is welan gum and / or xanthan gum, and the amount of addition is 0.01 to 0.1% by mass (externally divided) with respect to 100% by mass of the refractory composition. Insulated castable refractories for pumping, characterized by The heat-insulating castable refractory for pumping according to claim 1 or 2, wherein the lightweight refractory aggregate has a CaO · 6Al ₂ O ₃ composition and is porous. Stuff. The heat-insulating castable refractory for pumping according to claim 1 or 2, wherein the light-weight refractory aggregate has an Al ₂ O ₃ composition and is hollow.   The heat-insulating castable refractory for pumping according to any one of claims 1 to 4, wherein the amount of water added is 35% by mass or more (external ratio) with respect to 100% by mass of the refractory composition. Insulated castable refractory for pumping.   The heat-insulated castable refractory for pumping according to any one of claims 1 to 5, wherein the heat-insulating castable refractory for pumping has a flow value of 200 mm or more and a V funnel flow time of 60 seconds or less. Insulated castable refractory for pumping.   Light-weight fire-resistant aggregate with a bulk specific gravity of 1.0 or less, fire-resistant composition consisting of fire-resistant fine powder with an average particle size of 75 μm or less and alumina cement, and an anti-separation agent are kneaded with water, and the heat-insulated castable refractory for pumping obtained. Is transported to a spray nozzle using a pump and a pumping pipe, and sprayed together with compressed air and a quick setting agent, the light-weight fire-resistant aggregate, the fire-resistant fine powder, and the alumina cement A wet spraying method for heat-insulating castable refractories for pumping, wherein the volume ratio of the lightweight refractory aggregate to the total is 0.65 to 0.85.   The wet spraying construction method according to claim 7, wherein welan gum and / or xanthan gum is used as the anti-separation agent, and the amount added is 0.01 to 0.1% by mass (extra) with respect to 100% by mass of the refractory composition. A wet spraying method for heat-insulating castable refractories for pumping, characterized by: The wet spraying construction method according to claim 7 or 8, wherein the light-weight fireproof aggregate is a CaO · 6Al ₂ O ₃ composition porous and has a porous structure. Wet spray construction method. In the wet spraying construction method according to claim 7 or 8, wet the Pumping insulation castable refractory that a Al ₂ O ₃ composition as a lightweight refractory aggregate is characterized by using those hollow quality Spray construction method.   The wet spraying construction method according to any one of claims 7 to 10, wherein the amount of water added is 35% by mass or more (external ratio) with respect to 100% by mass of the refractory composition. Wet spray construction method for heat-insulated castable refractories for pressure feeding.   The wet spray construction method according to any one of claims 7 to 11, wherein the flow value of the heat insulating castable refractory for pumping is 200 mm or more, and the V funnel flow time is 60 seconds or less. Wet spray construction method for heat insulating castable refractories for pumping. In the wet spraying construction method in any one of Claims 7-12, the addition amount of the said quick setting agent shall be 0.1-3.0 mass% in conversion of solid content with respect to 100 mass% of the said refractory compositions. A wet spraying method for heat-insulating castable refractories for pumping.