WO2003033980A1

WO2003033980A1 - Monolithic refractory applying method and monolithic refractory used therefor

Info

Publication number: WO2003033980A1
Application number: PCT/JP2002/010767
Authority: WO
Inventors: Sakae Nakai; Tetsunori Ikebe; Yoichi Furuta; Jun Kimonji; Norikazu Shirama; Kiyoshi Goto; Yukihiro Nakamura; Koji Kawano; Yasuhiro Yamada
Original assignee: Krosakiharima Corporation; Nippon Steel Corporation
Priority date: 2001-10-17
Filing date: 2002-10-16
Publication date: 2003-04-24
Also published as: KR20040039191A; KR20040037277A; BR0212785A; BRPI0212785B1; JP4418233B2; CN1489683A; CN100529628C; KR100773574B1; JPWO2003033980A1

Abstract

An applying method excellent in applicability of a monolithic refractory to a molten metal vessel, a molten metal processing apparatus, or a high-temperature furnace and in applied body life as compared to conventional spraying methods and a monolithic refractory are disclosed. Applying water is added in advance to a refractory ultrafine powder of volatile silica and/or calcined alumina stored in a hopper and the mixture is kneaded. A monolithic refractory is compounded with a dispersant and a refractory aggregate containing 1-30 mass% of the refractory ultrafine powder mixed with the applying water. The compounded monolithic refractory is fed to a portion below the hopper while adding a quick setting agent, and centrifugally projected. Since the monolithic refractory is fed to the portion below the hopper, the fluidity imparted to the monolithic refractory can be of a low degree. Therefore, the amount of water for application can be reduced, and a local application can be facilitated by projecting the monolithic refractory in a predetermined range of angle.

Description

Description The method of applying irregular-shaped refractories and the irregular-shaped refractories used for them

Technical field

The present invention relates to a method for applying an amorphous refractory to a molten metal container, a molten metal processing apparatus or a high temperature furnace, and an amorphous refractory used for the method. Background art

Conventionally, spraying using irregular-shaped refractories has been performed as a lining or repair means for molten metal containers, molten metal processing equipment, high-temperature furnaces, and the like. As shown in the illustration in Fig. 6, the method is as follows. The quick-setting agent from 37 is added to the nozzle 36 with the compressed air of the air-compressor 38 and sprayed. This construction method is disclosed in, for example, JP-A-10-182462, JP-A-10-95678.

This construction method is based on the fact that spraying a pre-kneaded irregular-shaped refractory produces less dust than the dry spray method that adds construction moisture inside the nozzle, saves construction work, There are effects such as obtaining a construction body.

However, in this spraying construction, since the irregular refractory is transferred from the hopper to the nozzle via the pumping pipe, the amount of moisture applied to the irregular refractory increases in order to obtain stable pumpability. Accordingly, the structure of the construction body of the amorphous refractory becomes porous, and there is a disadvantage that strength and corrosion resistance are reduced.

In addition, this repelling construction involves rebound loss because the refractory is blown off with high-pressure compressed air. Although dust prevention is superior to dry spraying, it is not sufficient. In addition, since the construction is performed by blowing high-pressure compressed air, the construction body is hindered from being densified by air entrapment. There is also the disadvantage of being done.

In this spraying construction, it is conceivable to increase the pumping speed of irregular refractories in order to improve construction efficiency. However, the pipe resistance in the pumping pipe increases in proportion to the pumping speed. In order to counter this pipe resistance, it is necessary to reinforce the pumping pipe, increase the capacity of the pumping pump, or increase the inner diameter of the pumping pipe. Absent.

Also, it is known to add refractory ultrafine powder to irregular shaped refractories in spraying. These refractory ultrafine powders impart fluidity during application to irregular refractories. Fluidity makes the construction compact by the water reduction effect by reducing the amount of construction water added, and improves the hot strength required for the refractory construction body structure, corrosion resistance to molten metal, and the like. It also has an effect on the adhesion and adhesion required for spraying. .

Volatile silica or calcined alumina is known as the refractory ultrafine powder used here. Volatile silica or calcined alumina is easily available as an ultrafine powder, and exhibits an excellent water reducing effect. However, volatile silica or calcined alumina is chemically active and highly reactive with the quick setting agent, so that the refractory ultrafine powder is aggregated by the quick setting agent added during spraying, The viscosity of amorphous refractories increases rapidly at the nozzle where the quick-setting agent is added. This leads to pulsation and breathing phenomena at the time of discharge from the nozzle, resulting in a decrease in construction efficiency and a failure of the construction body. In this spraying work, by adding refractory coarse particles having a particle size of more than 10 mm or metal fibers with a length of about 5 to 50 mm to irregular shaped refractories, It is also known to be effective in imparting strength and preventing cracking. However, the addition of the quick setting agent increases the viscosity of the amorphous refractory, causing a pleasing phenomenon in which the added refractory coarse particles, metal fibers, or the refractory coarse particles and the metal fiber approach each other. There is a drawback that blockage is likely to occur and the workability is significantly reduced. Furthermore, in order to improve fluidity, refractory powder containing When the refractory coarse particles or metal fiber are used in combination with fixed refractories, the increase in viscosity after the addition of the quick setting agent is particularly remarkable, making spraying work substantially difficult.

Japanese Patent Publication No. 50-39403 proposes a method of performing centrifugal projection with a horizontally rotating impeller as a construction method of an amorphous refractory. However, this method is inferior in both the adhesion and corrosion resistance of the construction body compared to the spraying construction described above, and has not been widely used. Disclosure of the invention

An object of the present invention is to provide a construction method which is more excellent than conventional spraying methods in terms of workability of an amorphous refractory, a life of a construction body, and the like, and an irregular refractory used therefor.

The present invention relates to a method for applying an amorphous refractory to a molten metal container, a molten metal processing apparatus, or a high-temperature furnace. It is sent out below the hopper while adding, and then centrifugally projected.

In the construction method of the present invention, the supply of the irregular-shaped refractory to the discharge portion is performed by sending out the material below the hopper, so that the long and small inner diameter used in the conventional conventional spraying method is required. Since there is no pumping pipe, there is no problem with pipe resistance. As a result, amorphous refractories need only be given a small amount of fluidity, which can significantly reduce the amount of water required for construction. Furthermore, since compressed air is not required for centrifugal projection, the construction body can be further densified because there is no air entrapment.

The centrifugal projection in the present invention can be performed with a constant angular width in the circumferential direction. By projecting at a certain angle width, local construction becomes easy. Also, for example, if the inside diameter of the molten metal container to be installed is extremely large, the projection distance will be long, which will reduce the adhesion of irregular refractories, and it will not be easy to accurately project onto the work area. This problem can also be solved by moving the construction equipment closer to the vessel wall and projecting it at a certain angular width. In the present invention, the quick setting agent is added as needed. If added, air may be used as a carrier for the quick setting agent. However, in this case, the pressure and the flow rate of the air are slightly smaller than the high-pressure compressed air required for blowing the amorphous refractory from the blowing nozzle in the conventional blowing method. Therefore, there is no problem of air entrapment in the construction body.

Also in the present invention, when the amorphous refractory to be applied contains a refractory ultrafine powder such as volatile silica or calcined alumina, the addition of a quick-setting agent significantly increases the viscosity of the amorphous refractory. However, since the present invention is applied by centrifugal projection, and the supply of irregular-shaped refractories to the discharge section is sent downward from the hopper, nozzle clogging or pipe resistance seen with the conventional spraying method may be caused. No pulsation or breathing phenomenon occurs during discharge, and excellent workability can be obtained. As a result, when an amorphous refractory containing volatile silica or calcined alumina is used as the refractory ultrafine powder in the present invention, the strength and corrosion resistance of the construction body due to the water reducing effect of volatile silica or calcined alumina The effect of improvement and adhesion and adhesion by chemical activity can be fully exhibited.

Also, in the present invention, since there is no nozzle and no pressure feed pipe, even if an amorphous refractory to which refractory coarse particles or metal fibers are added is used, the nozzle blockage or pipe resistance observed by the conventional spraying method may cause the problem. The problem goes away. As a result, even when an irregular refractory containing refractory fine particles together with refractory coarse particles or metal fibers is used, the problem is caused even under particularly remarkable increase in viscosity due to the reaction between the refractory fine particles and the quick setting agent. The effect of preventing cracks and imparting strength to the construction body by adding refractory coarse particles or metal fibers is exhibited.

Furthermore, in the case of containing refractory ultrafine powder such as volatile silica or calcined alumina, the specific gravity of the powder itself is small, so in spraying, after being discharged from the spray nozzle, it is separated from other aggregates. It is easy and causes unevenness of construction. Refractory coarse particles and metal fibers are easily segregated in the refractory structure due to the difference in shape from other aggregates. In contrast, the present invention which is centrifugally projected Is not blown off by high-pressure compressed air as in spraying construction, so during the construction, separation and segregation of ultrafine powder, refractory coarse particles or metal fibers are prevented, and adhesion of irregular refractories is further improved. As a result, the structure of the obtained construction is homogenized, and the corrosion resistance and spoiling resistance are improved.

Next, an amorphous refractory which can be suitably used in carrying out the construction method of the present invention will be described.

The refractory aggregate of the amorphous refractory used in the present invention is a sintered alumina, an electro-alumina, a bauxite, a clay shale, a mullite, a silica stone, a chamotte, an andalite, a pyrolite, a silicon carbide, a molten carbide. to M G_〇 spinel, chrome ore, and one or more selected from Shirimana I bets like - silica, magnesia, magnesite Xia Ichiriki Lucia, a 1 ₂ 0 _3. In addition, any one or more selected from zirconia, carbon, clay, light-burned magnesia, pitch, meso-food pitch, infusible pitch, gaynitride, aluminum nitride, boron carbide, zirconium boride, chromium oxide, etc. Can be combined. The amorphous refractory used in the present invention uses refractory ultrafine powder as a part of the refractory aggregate. The preferred particle size of the refractory ultrafine powder is an average of 10 im or less as measured by a particle size distribution analyzer using a laser diffraction method.

Further, as the refractory ultrafine powder, volatile silica and / or calcined alumina excellent in imparting adhesiveness, adhesion, strength and corrosion resistance of amorphous refractories are preferable.

Volatile silica is also referred to as silica flour, silica fume, or microsilica, and is a non-crystalline substance that is generated by oxidizing SiO2 gas in the air during the production of silicon, fever silicon, zirconia, etc. Ultra fine silica powder. Spherical particles having an average of about 0.2 to 0.5 / xm are used, and the actual use form is secondary particles in which the submicron particles are aggregated. The quality of that is, S I_〇 ₂ Purity 9 0 wt% or more, and a specific surface area preferably about 5~4 O m S / ^ g.

Calcined alumina is obtained by firing aluminum hydroxide obtained by the Plier method. It is a thing. The sintering temperature is generally about 1000 to 1300, and the sintering temperature of the refractory raw material is a relatively low temperature. The α- A 1 ₂ 0 ₃ as a main component, A 1 ₂ 0 ₃ purity is generally 9 9 mass% or more. It is preferable to use those obtained as ultrafine powder having an average particle diameter of 10 or less. This is different from sintered alumina that uses calcined alumina as a raw material and is fired at a high temperature of 160 or more.

The proportion of the refractory ultrafine powder in the refractory aggregate is preferably from 1 to 30% by mass, and more preferably from 3 to 25% by mass. If the amount is too small, the water reduction effect cannot be fully exhibited. If it is too large, cracking and corrosion resistance tend to be reduced due to sintering shrinkage due to oversintering.

Dispersants are also called peptizers for their function. Gives fluidity to amorphous refractories and has a water reducing effect. The specific type of dispersant is not specified at all. Inorganic salts such as polymetaphosphate, sodium citrate, sodium tartrate, sodium polyacrylate, sodium sulfonate, polycarboxylate, carboxyl group-containing polyester, i8-naphthalene sulfonates And naphthalenesulfonic acid. A preferable addition amount is in the range of 0.05 to 1% by mass with respect to 100% by mass of the refractory aggregate.

As the binder, for example, alumina cement, magnesia cement, sodium phosphate, sodium silicate and the like are used. The addition ratio is preferably adjusted within the range of 1 to 15% by mass with respect to 100% by mass of the refractory aggregate, depending on the type of the binder. This binder is not necessarily required if sufficient coagulation can be obtained with the type and amount of quick-setting binder and refractory ultrafine powder.

The addition of coarse refractory particles or metal fibers to amorphous refractories is effective in preventing cracking, improving strength and corrosion resistance. The maximum particle size of refractory aggregate in amorphous refractories is usually 3 to 8 mm, but coarse particles of refractory have a larger particle size than this refractory aggregate, for example, 10 to 50 mm. Endurance As the material of the coarse particles, it is possible to use electrofused alumina, sintered alumina, electrofused vinyl, sintered spinel, silicon carbide, or refractory waste mainly composed of these. The addition amount is 50% by mass or less, preferably 1 to 40% by mass, based on 100% by mass of the refractory aggregate. If it is too large, the adhesion will be reduced.

The material of the metal fiber added to the refractory is steel, iron, stainless steel, or the like. Among them, stainless steel excellent in heat resistance is preferred. The diameter and the length are both good. For example, when the diameter is 0.1 to 2 mm, the length is preferably 5 to 50 mm. The cross-sectional shape does not matter, such as a circle and a polygon. The amount of addition is 10% by mass or less, more preferably 0.1 to 7% by mass, based on 100% by mass of the refractory aggregate. If it is too large, corrosion resistance is reduced.

Additives other than the above to the amorphous refractory of the present invention include, as necessary, organic fibers, ceramic fibers, thickeners, clay, CMC, bentonite, metal powder, lightweight materials, curing accelerators, and curing agents. A retarder, aluminum lactate, aluminum glycolate lactate, aluminum glycolate, silica sol, alumina sol and the like can be used alone or in combination. The irregular-shaped refractory used in the present invention is kneaded with a mixer or the like after addition of construction moisture in advance in construction. In the case of this type of refractory, the amount of water to be applied is 3 to 10% by mass of the dry refractory in this kneading process, and JISA 1101 (Japanese Industrial Standard: Slump test method for concrete) It is preferable that the slump value measured by a method according to the above is adjusted to a softness of, for example, 20 cm or less. If the working water content is less than this, the irregular shaped refractory after kneading will not be able to be smoothly fed down the hopper due to a decrease in fluidity and plasticity. If the amount of construction water is large, the strength and corrosion resistance of the irregular shaped refractory after construction will be insufficient. If the slump value exceeds 20 cm, irregular shaped refractories will easily flow out of the hopper by themselves, making it difficult to adjust the delivery amount. In addition, there is a tendency for the adhesion and filling of amorphous refractories to decrease. A more preferred slump value is 5 to 15 cm It is.

As a quick setting agent, either liquid or powder can be used. From the viewpoint of adhesion and adhesion strength of the amorphous refractory, the addition ratio should be 0.2 to 5% by mass in terms of solid content with respect to 100% by mass of the refractory aggregate of the amorphous refractory. preferable. Examples of the liquid quick setting agent include aqueous solutions of sodium aluminate, potassium aluminate, sodium silicate, potassium gayate, sodium phosphate, and the like. These liquid quick-setting agents may be combined with a cationic or anionic flocculant, if necessary. Examples of powdery quick-setting agents include sodium aluminate, potassium aluminate, sodium silicate, sodium phosphate, sodium carbonate, calcium chloride, calcium hydroxide, calcium oxide, calcium aluminate, and hydroxide. Magnesium, Portland cement, sodium sulfate, etc.

These quick setting agents may be added in a state of being mixed with the refractory fine powder. For example, refractory fine powder such as alumina may be mixed in a range of, for example, 50% by mass or less with respect to 100% by mass of the quick setting agent in terms of solid content. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an explanatory view of the construction method of the present invention.

FIG. 2 is an enlarged longitudinal sectional view of an example of a construction apparatus used in the present invention.

FIG. 3 is a sectional view taken along line AA of FIG.

FIG. 4 is an enlarged vertical sectional view of another construction apparatus used in the present invention.

FIG. 5 is a cross-sectional view of a part of the impeller of FIG. 4 taken along line BB.

FIG. 6 is an explanatory view of a conventional spraying method. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, repair of a molten steel ladle will be described as an example suitable for carrying out the present invention.

In FIGS. 1 and 2, a construction apparatus 1 includes a hopper 3 for accommodating a premixed amorphous refractory 2, and an irregular refractory 2 in the hopper 3. Screw filler 4 to be cut out, quick-setting agent supply device 7 for adding quick-setting agent to irregular-shaped refractory 2, stirrer rod 1a for stirring quick-setting agent and irregular-shaped refractory, irregular shaped refractory It is equipped with a horizontally rotating impeller 6 that projects centrifugal force 2 horizontally. The top plate of the hopper 3 is provided with an opening / closing plate 19 serving as an inlet for the irregular-shaped refractory 2. The hopper 3 has a taper of a lower drawing, and a vibrating motor 8 is provided on the tapered portion. The vibrating motor 8 facilitates sending out the refractory in the hopper 3.

The axis of the screw feeder 14 is the same as that of the drop cylinder 5, and the upper end of the shaft is supported by a bearing provided on the top plate of the hopper 3. Driving by evening 9. The screw feeder 14 also has a role of preventing the irregular-shaped refractory 2 from flowing down from the hopper 13 when construction is suspended.

Further, the lower end of the hopper 3 has a drop cylinder 5, and the lower end of the drop cylinder 5 of the hopper 3 is equipped with an impeller 6. The impeller 16 is rotated by a driving motor 21 mounted on a base 20 fixed to the drop cylinder 5. A cylinder shaft 22 is provided on the outer periphery of the drop cylinder 5, and an impeller 16 is rotatably mounted via a bearing 23.

The impeller 16 has an upper plate 24, a lower plate 25 facing the upper plate 24, and, as shown in FIG. 3, radial blades 26 connecting between the upper plate 24 and the lower plate 25. The rotating column 30 is fixed to the lower plate 25. The refractory 2 is applied with centrifugal force by the blades 26 of the impeller 16 and is projected radially around the rotation axis 10. The number of the blades 26 is preferably, for example, about 3 to 10 in the circumferential direction. Here is an example of eight holidays.

Although one drive motor 21 for rotating the impeller 6 is provided here, it may be provided on the left and right sides to maintain the right and left weight balance. A driving rotary body, for example, a pulley 27 is fixed to the output shaft of the driving motor 21, and is connected to the cylindrical shaft 22 by a V-belt 28.

The drive motor 21 is preferably of the inverter type and preferably of the type capable of reverse rotation. These impeller single-rotation drives are It is preferable to reinforce with 9, 43.

A plurality of flat or rod-shaped stirring rods 11a are provided at appropriate intervals above and below the rotating column 30 fixedly mounted on the impeller 16. As a result, the stirring rod 11a also rotates with the rotation of the impeller 16. These stirring rods 11a are preferably located in the drop cylinder 5 in order to make the stirring action of the quick-setting agent and the amorphous refractory more effective. Instead of the rotating support 30, the rotating shaft 10 of the screw feeder 14 may be further extended downward, and a stirring rod 11 a rotated by the rotation of the rotating shaft 10 may be provided.

When stirring between the quick-setting agent and the amorphous refractory is sufficient with the screw feeder 14, the stirring rod 11a is not necessarily required. Further, it is preferable that a stirring rod 11 b is provided on the rotating shaft 10 in the hopper to prevent the filling and solidification of the amorphous refractory in the hopper. The screw feeder 4 is rotationally driven by a drive motor 9 mounted on the hopper 3.

The quick-setting agent supply device 7 is composed of a supply pipe 14 that covers the pores 12 formed in the drop cylinder 5 with a jacket 13 and communicates with the inside of the jacket. The base end of the supply pipe 14 is connected to a pumping device for a quick-setting agent (not shown). The quick-setting agent supply device 7 is not limited to the one shown in the drawing, and it is sufficient that the quick-setting agent supply device 7 has a function of adding a quick-setting agent to the irregular-shaped refractory at or near the drop cylinder 5.

When projecting irregular shaped refractories, first, the construction equipment 1 containing premixed irregular shaped refractories 2 in the hopper 3 is suspended in a molten metal container 17 by a crane via a suspension cable 16. I do. Next, the screw feeder 4 and the stirring rod 11a are rotationally driven, and at the same time, the quick-setting agent is supplied to the irregular-shaped refractory in the drop cylinder 5. Thereby, the amorphous refractory 2 is sent downward from the dropping cylinder 5 while the quick-setting agent is added, and is also sufficiently mixed by the stirring rod 11a. Next, the amorphous refractory 2 is introduced into the center of the high-speed rotating impeller 6, and is projected on the inner wall of the molten metal container by centrifugal projection by the operation of the blade 26. By moving the construction equipment 1 up, down, left and right in the molten metal vessel, the irregular fireproof Project object 2.

The operation of the screw feeder, the addition of the quick setting agent, and the operation of the impeller are performed, for example, by operating the operation panel 15 from outside the molten metal container. The vertical movement of the construction equipment 1 can be controlled easily and accurately by using the electric chain block 18 in the middle of the suspension cable 16 without the need to operate heavy equipment such as cranes. .

4 and 5 show another example of a construction apparatus for carrying out the method of the present invention, which is used for projecting an irregular-shaped refractory with a constant angular width in a circumferential direction. The entire mechanism such as quick-setting agent supply and impeller one-rotation drive is the same as the apparatus shown in FIGS. Parts common to the parts and the like shown in FIGS. 1 to 3 are denoted by the same reference numerals.

In this example, an endless flat belt 39 is wound around the outer periphery of the blade 26 and the impeller 16. The winding of the flat belt 39 around the impeller 6 is reversed at one end of the impeller 16, and an open portion where the flat belt 39 is not wound is provided on the impeller 6. The flat belt is guided by a pulley 41, which is pivotally mounted on a horizontal support 40 above the impeller 6. Since the flat belt 39 is wound around the impeller 16, the driving force of the impeller 16 is transmitted, and the flat belt 39 rotates in synchronization with the impeller 16. Therefore, the rotation of the flat belt 39 is synchronized with the impeller.

The variable refractory 2 sent out from the drop cylinder 5 is dispersed in all directions by the impeller blades 26 of the impeller 16, but when it reaches the outer periphery of the impeller 6, the dispersion is blocked by the flat belt 39. After that, we move on this flat belt 39. When the variable refractory 2 reaches a position where the flat belt 39 is not wound around the outer periphery of the impeller 16, it is released from the restraint from the flat belt 39 and is projected to the outside. This makes it possible to project in one direction with a certain angular width. In the figure, the projection is shown in the right direction. An orientation guide 44 is provided at an open portion of the impeller 6 where the flat belt 39 is not wound. Orientation guide body 4 4 is fixed to horizontal support 40 at the top I do. The orientation guide body 44 can further narrow the projection angle of the irregular-shaped refractory 2.

Tables 1 to 3 show the working conditions of the examples of the present invention and the comparative examples, and the test results. The object of construction is a refractory-lined molten metal container with a bottom diameter of 3.0 m, a top diameter of 3.5 m, and a height of 3.0 m. An attempt was made to form a construction body of about 8 O mm. Examples 1 to 13 are constructions using the impeller type construction apparatus shown in FIGS. Irregular refractories which had been kneaded with water for construction in advance were put into a hopper, and centrifugally projected while adding a quick-setting agent. The working conditions were as follows: discharge speed: 6 m ³ Z hours, impeller diameter: 50 O mm, rotation speed: about 800 rpm. In Comparative Example 5, an amorphous refractory was constructed by centrifugal projection without adding a quick-setting agent. Other conditions were the same as in Example 1 described above.

In Comparative Examples 1 to 4 and Comparative Example 6, the irregular-shaped refractories shown in the table were sprayed using a spraying device corresponding to FIG. The amorphous refractories shown in the table, after adding the working moisture and kneading, were sent to the nozzle by a pressure pump, and sprayed while adding a quick-setting agent together with high-pressure air in the nozzle. Construction conditions discharge speed: it was 2 m ³ Roh time.

In the composition of the amorphous refractory used in each example, the average particle diameters of the volatile silica and the calcined alumina were determined by a laser diffraction method. The particle size of the other refractory aggregate are those obtained by the measurement was ³ according to the JI s old eye opening. The slump value was measured for the kneaded material to which the working moisture was added according to JISA101.

'Tables 1 and 2 show the construction of alumina-magnesia irregular refractories. The construction was carried out by spraying or spraying on the lining wall composed of alumina-magnesia irregular refractories. Table 3 shows the construction of magnesia-carbon irregular refractories. The construction was performed by projecting or spraying the magnesia-carbo brick on the lining wall.

For the adhesion of irregular refractories, the adhesion rate to the vertical wall was determined. Workability is The degree of workability caused by pipe resistance, which is mainly affected by fluidity, was measured. For example, pipes with high pipe resistance may cause pulsation and breathing or nozzle clogging at the time of discharge, resulting in poor workability. …: Best, 〇: Good, △: Somewhat bad, X: Bad

As a test method of the compactness of the construction body, a test piece was cut out from the construction body and the bulk specific gravity was measured. The higher the bulk specific gravity, the higher the denseness.

The spalling resistance is determined by cutting a test piece from the construction body, repeating heating and air cooling, and visually evaluating the degree of cracking on a scale of 1 to 5 on a scale of 1 to 5. It shows that it has excellent properties.

【table 1】

1. The figures for the non-conformable refractory composition are% by mass. The numerical value in parentheses is the outer mass%.

2. Corrosion resistance is an index with Comparative Example 1 being 100. The larger the value, the greater the erosion.

[Table 2]

[Table 3]

2. Corrosion resistance is an index with Comparative Example 5 being 100. The larger the value, the greater the erosion.

From the test results of the examples of the present invention shown in Tables 1 and 3, it can be seen that the present invention can provide excellent workability even with a small amount of working water. In particular, the use of an amorphous refractory to which calcined alumina or volatile silica is added further enhances the adhesion, workability, denseness of the structure of the work body, and corrosion resistance. There is no problem in the workability even with the irregular shaped refractories shown in Examples 4 to 7 in which the refractory coarse particles or metal fibers are added, and the spalling resistance of the construction body is further improved by the characteristics of the refractory coarse particles or metal fibers. Improved.

On the other hand, of Comparative Examples 1 to 4 and Comparative Example 6 which were sprayed, Comparative Example 1 had relatively high adhesion, but was poor in workability and denseness, and ultimately inferior in corrosion resistance. .

Comparative Examples 3 and 6 used amorphous refractories that did not contain both volatile silica and calcined alumina, but added a large amount of water to ensure workability. As a result, the compactness of the construction body structure has been reduced, and the corrosion resistance has also been significantly reduced.

In Comparative Example 2 and Comparative Example 4 in which refractory coarse particles were added, smooth discharge was not performed, and workability was particularly deteriorated. Although the application was performed by centrifugal projection, in Comparative Example 5 in which no quick-setting agent was added, the adhesion was significantly reduced.

In addition, since the test methods of Comparative Examples 2, 4 and 5 were not easy to secure the test pieces, the test for the denseness, spalling resistance and corrosion resistance of the processed structure was not performed. Industrial applicability

Construction according to the present invention is performed in molten metal containers such as blast furnaces, blast furnace gutters, converters, ladles, tandems, degassing furnaces, mixed iron cars, mixed iron furnaces, soaking furnaces, heating furnaces, firing furnaces, incinerators, and melting furnaces. It can be applied to the lining of molten metal processing equipment and high-temperature furnaces or its repair. It can also be applied to hot wall surfaces such as hot repair of furnace walls.

According to the present invention, the workability of the amorphous refractory is improved, and the obtained construction body is also improved. It will have excellent properties, and will greatly contribute to improving the operation rate of various industrial furnace equipment by reducing the number of construction steps and the amount of irregular refractories used.

Claims

The scope of the claims

1. A method for applying an amorphous refractory to a molten metal container, molten metal processing equipment or high-temperature furnace,

A method for applying irregularly shaped refractories that have been added and kneaded in advance and stored in a hopper, sent out below the hopper while adding a quick-setting agent, and then centrifugally projected.

2. The method of claim 1, wherein the centrifugal projection is performed at a constant angular width in the circumferential direction.

3. The amorphous refractory is an amorphous refractory obtained by combining a refractory aggregate containing 1 to 30% by mass of a refractory ultrafine powder such as volatile silica and calcined aluminum or calcined aluminum with a dispersant. 3. The method for applying an amorphous refractory according to claim 1 or 2.

4. The amorphous refractory according to any one of claims 1 to 3, wherein the amorphous refractory contains 100% by mass of refractory aggregate and 50% by mass or less of refractory coarse particles. Construction method of the object.

5. The amorphous refractory according to any one of claims 1 to 4, wherein the amorphous refractory further comprises 100% by mass or less of a metal firer with respect to 100% by mass of the refractory aggregate. Construction method of the object.

6. The working water content of the amorphous refractory to which the working moisture was previously added and kneaded was 3 to 10% by mass relative to 100% by mass of the dry refractory amorphous refractory, and the slump value was JISA11. The method for applying an irregular shaped refractory according to any one of claims 1 to 5, wherein the measuring method is 20 cm or less in a measuring method based on the standard of 01.

7. In the application of irregular shaped refractories to molten metal containers, molten metal processing equipment or high-temperature furnaces, the irregular shaped refractories stored in the hopper by adding and kneading the moisture in advance are added to the hopper while the quick-setting agent is added. An irregular refractory to be used for the construction of an irregular refractory that is sent downward and then centrifugally projected. 1 to 30% by mass of a refractory ultrafine powder made of volatile silica Z or calcined alumina An amorphous refractory containing refractory aggregate and dispersant.

8. The irregular-shaped refractory according to claim 7, wherein 50% by mass or less of refractory coarse particles are mixed with 100% by mass of refractory aggregate.

9. The irregular-shaped refractory according to claim 7 or 8, wherein metal fiber is blended in an amount of 10% by mass or less with respect to 100% by mass of the refractory aggregate.

100. The amorphous refractory to which the working moisture has been added and kneaded in advance has a working moisture content of 3 to 10% by mass with respect to 100% by mass of the dry powdered amorphous refractory, and a slump value of JISA 1 The amorphous refractory according to any one of claims 7 to 9, which has a size of 20 cm or less in a measuring method according to the standard of 101.