JP4452030B2 - Refractory reinforced with rod-shaped molded body made of inorganic fiber and method for producing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refractory material used for lining of kiln furnaces, holding containers, conveyance paths and the like for melting and refining metals such as steel, waste treatment, glass and cement production, high temperature treatment and the like.
[0002]
[Prior art]
Refractories are widely used in large quantities for refining and holding molten metal, heat treatment of materials, and the like. At the start of use and at the end of use, a rapid temperature change occurs due to temperature rise or cooling. In addition, for example, a rapid temperature change may occur between batch processes. Since the refractory is thermally expanded, a thermal stress is generated inside the refractory along with a rapid temperature change, which may destroy the refractory. This phenomenon is called thermal shock failure.
With long nozzles used to guide the molten steel from the ladle ladle to the tundish in continuous casting of molten steel and immersion nozzles used to guide the molten steel from the tundish to the mold, thermal shock fracture often occurs and becomes a problem. ing.
[0003]
As one means for solving this problem, a high heat-resistant and high-strength pipe for molten metal in which a carbon fiber converging body is arranged in a refractory matrix is disclosed in Patent Document 1, and a bundle of carbon fibers is added to a refractory having a through hole inside. Alternatively, Patent Document 2 describes a method of winding a mesh. Patent Document 3 describes a method of impregnating or applying a thermosetting resin to carbon fibers in order to firmly bond fibers or fibers and refractories.
[0004]
[Patent Document 1]
JP 59-156971 A
[Patent Document 2]
JP-A-2-133166
[Patent Document 3]
JP 59-35069 A
[0005]
[Problems to be solved by the invention]
All of these methods use carbon fiber yarns, strings, tapes, tows, bundles, and nets, cloths, felts, papers and mats made of these. Hereinafter, these are referred to as carbon fiber convergence bodies. These converging bodies have the disadvantage that they do not have shape-retaining properties themselves, or are poor, and are difficult to install in the form desired on the refractory surface or inside. Also, derived from this, slack is likely to occur because it is difficult to place such a shape-retaining property on the refractory surface or inside in a straight line. For this reason, even if carbon fiber having high strength and high elastic modulus is used, prestress cannot be applied to the refractory in which the carbon fiber is installed, and therefore a sufficient function for preventing destruction cannot be obtained. In addition, since the carbon fiber converging body is easily frayed, the carbon fiber converging body may be used separately when the refractory is manufactured.
[0006]
In addition, since these converging bodies have large voids between the individual fibers, a large amount of resin is easily absorbed when impregnated or coated with a resin, etc. Become an organization. In such a case, at a high temperature corresponding to the use temperature of the refractory, the volatile matter in the resin disappears and becomes very porous. Not only is the strength low, but also the fiber and the carbon originating from the resin are easily oxidized.
An object of the present invention is to provide a refractory material with high durability that is less prone to cracking due to thermal shock and the like, and a method for manufacturing the refractory.
[0007]
[Means for Solving the Problems]
  In order to solve the problem, the gist of the present invention is as follows.
(1) A refractory reinforced with a rod-shaped molded body made of inorganic fibers having a diameter of 1 to 10 mm and a length of 10 mm or more, wherein the rod-shaped molded body bundles inorganic fibers using a phenol resin as a binder. Or twisted or knitted, or further bundled with inorganic or organic fibersPretensionedIn the molded bodyAnd the rod-shaped molded body is linear, annular or spiral parallel to the longitudinal direction.A refractory reinforced with a rod-shaped molded body made of inorganic fibers.
(2) The rod-shaped body isA rod-shaped molded body produced by applying tension to the inorganic fiber when the phenol resin is curedA refractory material reinforced with a rod-shaped molded body made of inorganic fibers according to the above (1).
(3) A refractory reinforced with a rod-shaped molded body made of inorganic fibers according to (1) or (2), wherein the rod-shaped molded body is installed on a part or all of the outer periphery of the refractory.
(4) A refractory reinforced with a rod-shaped molded body made of inorganic fibers according to any one of (1) to (3), wherein the rod-shaped molded body is installed inside the refractory.
(5)(1) to (1), wherein the inorganic fibers are carbon fibers.4) A refractory reinforced with a rod-shaped molded body made of an inorganic fiber according to any one of the above.
(6) The above-mentioned (1) to (1), characterized in that the inside is a lump, plate or rod-shaped refractory filled5) A refractory reinforced with a rod-shaped molded body made of an inorganic fiber according to any one of the above.
(7)(1) to (1) above, wherein the rod-shaped molded body having a mass after being embedded in coke powder and heated at 600 ° C. for 3 hours is 5% or more of the mass before heating.6) A refractory reinforced with a rod-shaped molded body made of an inorganic fiber according to any one of the above.
(8(1) to (1), wherein the rod-shaped molded body is assembled in a mold frame, or after the rod-shaped molded body is assembled, a mold frame is installed around the mold mold, and then poured into the mold frame and poured into a refractory.7). A method for producing a refractory reinforced with a rod-shaped molded body made of an inorganic fiber according to any one of 1).
(9(1) to (1) to (1) above, wherein after pouring into the mold and pouring the refractory, the rod-shaped molded product is poured into the refractory.7) A method for producing a refractory reinforced with a rod-shaped molded body made of an inorganic fiber according to any one of.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In this invention, it replaces with the conventional convergence body and uses the rod-shaped molded object which consists of inorganic fibers. Since the rod-shaped molded body has shape retaining property, it does not sag when manufacturing the refractory, and can be installed on the surface of the refractory or inside the refractory as intended. Further, the fibers constituting the rod-shaped molded body are not frayed. In addition, the rod-shaped molded product referred to here is a material that does not deform and fall even if a sample having a length of about 300 mm is horizontally applied with a span of about 200 mm without applying tension.
[0009]
  BookThe invention is, for example, a refractory 2 reinforced with a rod-shaped molded body 1 made of inorganic fibers having a diameter of 1 to 10 mm and a length of 10 mm or more as shown in FIG. The refractory is reinforced by the presence of the rod-shaped molded body 1 in the rectangular refractory 2.
  If a rod-shaped molded body made of inorganic fibers is contained in the refractory, or disposed outside, the refractory is reinforced because the rod has high tensile strength. This makes it difficult to break due to thermal stress. Further, even if cracks occur due to breakage, the progress of cracks and even greater breakage can be suppressed by the crosslinking effect due to the pull-out resistance of the rod-shaped molded body.
  In order to express such effects, the rod-shaped molded body needs to have a diameter of 1 mm or more, but if it exceeds 10 mm, the durability of the entire refractory may be reduced due to oxidation or melting of the rod-shaped molded body. . The cross-sectional shape is not particularly limited, and may be, for example, a circle, an ellipse, a polygon, a star, or a flower.
  Further, the length needs to be 10 mm or more in order to obtain a sufficient crosslinking effect. In the case of a straight line as shown in FIG. 3, the length of the rod-shaped molded body is at most the maximum dimension of the refractory.
[0010]
  BookIn the invention, the rod-shaped molded body made of inorganic fibers may be radially or radially inside and / or outside the refractory.Is longArranged in a straight, annular or spiral cylinder parallel to the handMay. The rod-shaped molded body may be installed both inside and outside, and may be a combination of two or more of radial, parallel to the longitudinal, annular, and spiral. Further, the spiral may be a combination of double or more spirals or spirals having opposite pitches. FIG. 1 shows the case where the rod-shaped molded body 1 is radially present in four locations on the same circumference, FIG. 2 shows the case where the rod-shaped molded body 1 is linearly parallel to the longitudinal direction, and FIG. FIG. 5 shows a case where the rod-shaped molded body 1 is in an annular shape, and FIG. 5 shows a case where the rod-shaped molded body 1 is spirally embedded.
  The refractory may be a refractory structure combined with hardware. For example, a dip tube of an RH degassing facility having an iron plate or bar called a core metal or an iron core as a support, a gas blowing lance having an iron pipe as a center, and the like.
[0011]
  BookThe invention relates to a refractory material characterized in that the rod-shaped molded body is installed on a part or all of the outer periphery of the refractory material.May be. FIG. 6 shows a case where the rod-shaped molded body 1 is installed parallel to the longitudinal direction on a part of the outside of the refractory 2, and FIG. 7 shows a rod-shaped molded body without providing a gap on the entire outer periphery of the refractory 2. FIG. 8 shows a case where the rod-shaped molded body 1 is spirally installed on a part of the outer periphery of the refractory 2, and FIG. FIG. 10 shows a case where the rod-shaped molded body 1 is installed in an annular shape without providing a gap in a part of the outer periphery.
  If the rod-shaped compact is provided on a part or all of the outer periphery of the refractory, for example, if it is a cylindrical refractory, strong reinforcement against tensile stress generated on the outer periphery of the refractory when a high-temperature substance exists inside Therefore, the refractory is difficult to break.
[0012]
  BookThe invention relates to a refractory material characterized in that the rod-shaped molded body is installed inside the refractory material.May be.
  When the rod-shaped molded body is installed inside the refractory, the reinforcing effect increases the strength of the refractory and makes it difficult to break it. Even if cracks occur, the cracks hardly propagate due to the cross-linking effect of the rod-shaped molded body, and even greater destruction can be prevented.
[0014]
  BookThe invention is a binder.Using phenolic resin asIt is a molded body in which inorganic fibers are bundled, twisted or knitted, or further bundled with inorganic fibers or organic fibers. Inorganic fibers may be bundled, twisted or knitted. Bundling means that the fibers are adjacent in parallel. Twisting together means twisting together, and twisting the fibers together to make them like ropes. Knitting is a combination of fibers misplaced, including braids and lily yarns.
[0015]
  As a binderHaEnol resinUse. A suitable solvent may be used together with the binder. The binder is B₄Powders such as C, SiC, glass, and metal may be included. These exhibit the effect of increasing the strength of the rod at high temperatures and suppressing the oxidation of carbon fibers and residual carbon.
  When using a resin as a binder, first, the resin is impregnated between inorganic fibers, and this is bound from the outside with another inorganic fiber, or pulled out through a die or the like. For this reason, excess resin is extruded and removed from between the inorganic fibers, and a rod-shaped molded body with a small amount of resin can be obtained. For this reason, the strength of the rod-shaped molded body is high and hardly oxidized.
[0016]
Moreover, when a rod bundled with resin is created while applying tension to the inorganic fiber, a rod-shaped molded body with pretension applied can be produced. Using this to create a refractory, combined with the lack of deflection as described above, it is possible to obtain a prestressed refractory, which is extremely effective in suppressing thermal shock destruction. To do.
Further, a bundle obtained by bundling, twisting, or knitting may be immersed in a liquid sizing agent such as a resin. A rod-shaped molded body can be prepared by applying tension and curing as it is without binding from the outside.
The straight bar can be manufactured by applying tension. An annular, spiral, or polygonal rod-shaped molded body can be produced by winding it around a suitable frame and curing it.
[0017]
  BookThe invention is based on phenolic resinWith fatYes, carbon remains after heat treatment in a non-oxidizing atmosphere. Since this carbon, that is, the remaining coal, binds particles such as other refractory aggregates constituting the refractory, and also functions as a kind of refractory, it is a suitable resin for use in refractories. For this reason, it is also very suitable as a resin for bundling inorganic fibers.
[0018]
  BookInvention is inorganic fiberTheCarbon fiberOr in this caseHigh strength and high heat resistance. The disadvantage is that it disappears by oxidation. When carbon fibers are bundled with a phenol resin, the fibers are integrated by carbon originating from the resin, and the specific surface area can be reduced. For this reason, oxidation resistance can be improved.
[0019]
  BookThe invention is characterized in that it is a block-like, plate-like or rod-like refractory filled inside.May. The present invention can be applied not only to pipe-shaped refractories but also to lumps, plates, and rod-shaped refractories, and can suppress peeling and cracking of the refractory surface.
[0020]
  BookThe invention is characterized in that the angle formed by the working surface with all or a part of the axis of the rod-shaped molded body is 45 to 90 °.May. If the angle between the whole or part of the axis of the rod-shaped body and the working surface is 45 to 90 °, it is effective to generate cracks parallel to the working surface inside the refractory or to peel off the surface of the refractory due to the crack. Can be suppressed. The working surface is a contact surface between a refractory and a high temperature or corrosive substance held by the refractory. If the angle is less than 45 °, the effect is insufficient.
[0021]
  BookThe invention is characterized by using a rod-shaped molded body in which the mass after being embedded in coke powder and heated at 600 ° C. for 3 hours is 5% or more of the mass before heating.May. When the inorganic fibers are converged by the binder, volatile components in the binder are dissipated during drying, heat treatment, or use of the refractory of the present invention, and voids are formed around or inside the rod-shaped molded body. Since the voids adversely affect the corrosion resistance and slag infiltration resistance of the refractory as defects, the voids should be as small as possible. The amount of voids is affected by the ratio of the binder and fiber used for converging the rod-shaped molded body, and the ratio of the volatile components in the binder. As an index for comprehensively evaluating these, it is effective to embed a rod-shaped molded body in coke powder and heat at 600 ° C. for 3 hours, and specify the ratio of the mass after heating to the mass before heating. If this ratio, that is, (mass after heating) / (mass before heating) is 5% (= 0.05) or more, there are few defects in the refractory and hardly affect the corrosion resistance and slag infiltration resistance. This ratio should be as high as possible, preferably 20% or more.
[0022]
As the inorganic fibers, carbon fibers and glass fibers, for example, inorganic fibers such as alumina, alumina-silica, alumina, mullite, zirconia, magnesia-silica, magnesia-silica-calcia can be used. As described above, carbon fibers are particularly excellent from the viewpoints of strength and heat resistance. On the other hand, inorganic fibers such as alumina-silica, alumina, mullite, zirconia, and magnesia-silica are not lost by oxidation, and are effective when oxidation is a concern. It is also possible to use organic fibers for binding. In addition, it is also possible to use these fibers in combination of two or more. As the organic fiber, for example, an aramid fiber, a fiber known by a trade name of Zylon, a polyurethane fiber, or the like can be used.
[0023]
The rod-shaped molded body may be linear, circular, spiral, or other curved shape, and may be corrugated or not constant in thickness. It is preferable that the rod-shaped molded body has branches, protrusions, and irregularities because it is difficult to pull out. When producing the rod-shaped molded body, twisting the fibers or bundling them with fibers is advantageous for drawing because the surface is uneven. By taking measures such as devising the twisting method or bundling with thick bundles of fibers, it is possible to create a rod with a larger surface roughness. Further, a rod-shaped molded body having a branch can be produced by twisting a short rod-shaped molded body or binding it with fibers.
[0024]
Any commonly known refractory can be used as the base material. For example, various alumina-silica materials such as magnesia, calcia, spinel, chromite, chromia, alumina, mullite, silica, meteorite, chamotte, porphyry shale, bauxite, clay, andalusite, sillimanite, kyanite, zircon, Zirconia, SiC, B_FourIt is a refractory material in which various carbon sources such as carbides and borides such as C, scale-like graphite, coke, earth-like graphite, artificial graphite, and pitch are used as an aggregate, and binders and various additives are added to these as necessary. In addition, when using carbon fiber as a raw material of a rod-shaped molded object, it is better to use a refractory containing carbon from the viewpoint of suppressing its oxidation.
[0025]
  Next, the manufacturing method of the refractory of this invention is demonstrated.
  If cast refractories are used, it is easy to install a rod-shaped body. That is, it can be manufactured by assembling a rod-shaped molded body in a mold frame, or after assembling a rod-shaped molded body, placing a mold frame around the rod-shaped molded body, and then pouring a cast refractory kneaded into the mold frame. . The rod-shaped molded body may be partially fixed to the mold. By doing so, it is possible to obtain a cast refractory molded body in which the rod-shaped molded body is present in a surely aimed shape.
  Further, after pouring the refractory into the mold, the rod-shaped molded product may be poured into the refractory..
[0026]
In order to embed a bundled rod-shaped molded body in a refractory material, it is easy to embed the material in a clay or a kneaded material during refractory material molding. When forming a refractory, it is also possible to make a hole or insert a rod-shaped body by perforation, pour the surroundings and fill with a refractory or an adhesive.
[0027]
When installing the rod-shaped molded body outside the refractory, place the rod-shaped molded body along the surface and fix it with an adhesive or binding material. After setting in advance, put the clay or kneaded material in the mold and mold it with the rod-shaped molded body, or wrap the flexible rod-shaped molded body around the refractory surface, or combine these methods Can take. After arranging the rod-shaped molded body, it may be further pressed with a binder or hardware. Moreover, it is also possible to manufacture a refractory containing a rod-shaped molded body by covering with a refractory clay or a kneaded material.
The volatile matter in the binder becomes a gas when the refractory receives heat, which may damage the refractory. In order to avoid this, if necessary, the volatile matter may be removed by performing a heat treatment or the like on the rod-shaped molded body or the refractory in which the rod-shaped molded body is embedded.
[0028]
【Example】
[Example 1]
The effect of the present invention was confirmed at the laboratory level.
Carbon fiber (PAN-based, strength about 5000 MPa, elastic modulus about 24 tf / mm²) While applying phenolic resin, and then winding the same fiber bundle spirally around it to make it 6 mm in diameter and about 5 m in length, and then curing the resin to 200 mm in length. The rod-shaped molded body was prepared by cutting. In addition, the ratio of the carbon fiber and the phenol resin in the rod-shaped molded body was 40:60 (volume ratio).
[0029]
As an example of the present invention, a casting material (castable) containing alumina as a main component and containing 5% by mass of carbon was used as a base material, and three prepared rod-shaped molded bodies were embedded inside at intervals of about 40 mm in parallel to the longitudinal direction. A sample of 114 × 230 mm was prepared. Moreover, the sample which does not embed a rod-shaped molded object as a comparative example was also created.
The ratio of the mass after the rod-shaped molded body was embedded in coke powder and heat-treated at 600 ° C. for 3 hours to the mass before heat treatment was 45%.
The embedding procedure was as follows. Put the kneaded casting material into a casting mold (width 114mm x length 230mm x depth 65mm) up to a depth of 30mm to smooth the surface, and here one piece centered on the rod-shaped body with a length of 200mm The left and right sides were placed on both sides with a gap of 40 mm. The direction of the rod-shaped molded body was parallel to the 230 mm side of the mold, and the top and bottom of the rod-shaped molded body were spaced 15 mm apart from the 114 mm side of the mold. Then, the remaining 35 mm depth of pouring material was added, and the surface was smoothed and then allowed to cure at room temperature for 24 hours. Thereafter, the frame was removed and dried at 110 ° C. for 24 hours.
[0030]
These were immersed in 1600 ° C. hot metal and allowed to cool, and then cracks in the cross section were observed. The situation of both cracks is shown in FIG. In all cases, the oxide layer 4 having almost the same depth was observed, but in the comparative example (FIG. 12B) in which the rod-shaped molded body 1 was not embedded in the refractory 2, the mesh-like crack 3 developed. In the embedded example of the present invention (FIG. 12A), the crack 3 was significantly reduced.
[0031]
[Example 2]
The present invention was applied to a lance for blowing powder into molten steel.
As an example of the present invention, a spiral rod-shaped molded body in which carbon fibers are bundled with a phenol resin was embedded in a lance. The rod material and base material were the same as in Example 1.
The normal lance used as a comparative example has a length of 5m covered with a refractory, an outer diameter of 300mm, a central iron pipe with an outer diameter of 100mm, and a steel stud with a length of 50mm on the outside of the pipe. They were attached by welding radially at 90 ° intervals at a pitch of approximately 200 mm. The same stud was welded to the lower end of the pipe. The carbon fiber rod-shaped body is made into a spiral shape with a diameter of 200 mm and a pitch of 200 mm, and is covered with a tape from 0 m to 4 m from the lower end of the iron pipe. Temporarily stopped. These were set in a casting form and poured into the casting material.
[0032]
After drying at 350 ° C., gas was blown into the molten steel in the molten steel ladle for operation. Observed after 10 uses, the normal product without the helical rod embedded (Comparative Example) showed vertical cracks parallel to the lance length at almost 90 ° intervals, whereas rod-shaped molding made of carbon fiber. In the case where the body was embedded (invention example), no significant vertical crack was observed.
[0033]
[Example 3]
The present invention was applied to a dip tube of an RH degassing facility. The rod-shaped molded body had a diameter of 4 mm and was similarly prepared using alumina fiber and phenol resin.
As an example of the present invention, a ring-shaped rod-shaped molded body was embedded in a castable at the lower end of a 300 tRH degassing apparatus dip tube having an outer diameter of 1500 mm, an inner diameter of 800 mm, and a height including a flange of 750 mm. The ring was formed into an annular shape with a diameter of 1300 mm, and the end portions were not particularly joined to each other so that about a quarter of the circumference overlapped.
[0034]
A magcro brick is set inside the core, and a steel stud with a height of 60 to 100mm is welded to the lower end and outer periphery of the core with a pitch of about 100mm. At some points, the mold was set, and then the alumina-spinel casting material was applied. This was dried at 350 ° C. and then attached to the RH lower tank for use. Observed when used about 60 times on the ascending side, the rod-shaped molded body as a comparative example and the one not embedded with string-like fibers showed many vertical cracks, but the one embedded with a rod generated cracks. Was clearly less.
[0035]
[Example 4]
The present invention was applied to a sleeve brick of a converter bottom blowing tuyere. As the rod-shaped molded body, one having a diameter of 4 mm and a length of 800 mm prepared in the same manner as in Example 1 using carbon fiber and phenol resin was used.
As an example of the present invention, a magnesia-carbonaceous clay having a carbon content of 20% by mass, which is a base material, is used as a base material when manufacturing a bottom-blown tuyere sleeve brick having a length of 950 mm and an outer diameter of 450 mm of an upper-bottom blow converter. In this method, the rod-shaped compacts are placed along the length of the brick and covered with clay, and 12 cores are embedded almost evenly in the circumferential direction at almost the center in the thickness direction, that is, approximately every 30 °. It is. After drying this, it mounted on the converter and tried it. In the comparative example in which the rod-shaped molded body was not embedded, replacement was performed about four times during one converter cost, while in the present invention example, only two replacements were required.
[0036]
[Example 5]
As an example of the present invention, a magnesia-carbon brick used for an inclined part (upper part, throttle part) of a converter was embedded with a rod-shaped molded body made of carbon fiber. The same carbon fiber rod-shaped molded body as in Example 1 was used. Half of the clay with a graphite content of 18% by mass was put in a mold, and two rod-shaped compacts 50 mm shorter than the mold were arranged along the longitudinal direction evenly in the width direction, and further press-molded with the clay. It was built after drying. In the comparative example in which the rod-shaped molded body was not added, the brick surface was considerably peeled when the number of times of use of the converter exceeded about 1000 times, whereas in the present invention example in which the rod-shaped molded body was embedded, there was little peeling.
[0037]
[Example 6]
The present invention was applied to the SN plate. The SN plate is a sliding nozzle plate, also called SG, that is, sliding gate, or SV, that is, sliding valve, which makes two or three refractory plates with holes in surface contact, and the degree of deviation of the holes. In order to control the flow rate of molten metal or the like.
As an example of the present invention, the rod-shaped molded body of Example 1 is not cured on the periphery of a 40 mm thick SN plate containing alumina as a main component, carbon of about 12% by mass and silica of about 8% by mass and impregnated by baking. I made a prototype that was wrapped to the full width. In addition, the normal product as a comparative example is a steel hoop piled up and wound to a thickness of about 5 mm. When these were used for a ladle, the comparative example developed a radial crack around the hole when used three times, and it could not withstand any further use, but the example of the present invention had a slight crack even when used three times. It was reusable.
[0041]
[Example 10]
A 5-mm-thick alumina long fiber yarn (braided string) was immersed in a phenolic resin soaked in the resin and then removed, and the excess resin was dropped and cured, followed by curing at about 300 ° C. to produce a rod-shaped molded body. . An annular molded body was prepared by winding a straight rod by applying tension during curing and winding it around a cylindrical mold. The ratio of the mass after these rod-shaped compacts were embedded in coke powder and heat-treated at 600 ° C. for 3 hours to the mass before heat treatment was 25%.
This rod-shaped molded body was applied to an RH dip tube. An annular shaped body with a diameter of 1000 mm is lifted 20 mm from the lower end of the core metal and temporarily fixed with adhesive tape in some places on an iron stud attached to the lower end of a core metal with a diameter of about 1000 mm and a length of about 800 mm. In addition, four 800 mm-long straight rod molded bodies were lifted 20 mm from the steel stud core bar every 90 °, and temporarily fixed with an adhesive tape. Thereafter, the mold was set, and an alumina-spinel casting material was cast and applied, followed by vibration at 2G for 3 minutes. Further, four straight rod molded bodies having a length of 100 mm were pushed into the poured material perpendicularly to the lower end surface. The pushing-in position was set at a position approximately one-half of the thickness of the dip tube wall in a direction 45 ° away from the position where the 800 mm straight bar was installed. The position was slightly shifted if it could not be pushed in by hitting the hardware. These series of operations were performed with the flange for fastening the dip tube to the RH lower tank down and the bottom end up.
After curing at room temperature for 1 day, the frame was removed, dried at 300 ° C., and then attached to the RH lower tank.
Normally, when used about 50 times, a vertical crack occurs at the lower end of the dip tube, and after 100 times, the casting material at the lower end may fall off, but in the dip tube provided with a rod-shaped molded body, the vertical crack occurs. The cast material did not stand out even after 100 times, and the casting material did not fall off.
[0042]
[Example 11]
A burner tile (a member used for a burner outlet of a heating furnace) provided with the rod-shaped molded body described in Example 10 was manufactured and used.
In producing a burner tile with a truncated cone-shaped bore hole (inside diameter 100 mm, inside diameter of furnace outlet 250 mm) inside with a casting material, two 300 mm diameter annular molded bodies and a 300 mm long straight rod were first prepared. Four molded bodies were assembled like a skeleton. Rings are arranged in parallel at an interval of 80 mm, and four straight bars are attached to the ring at 90 ° intervals perpendicular to the ring surface, and look like a torii when viewed from a direction parallel to the ring surface. Assembled. Insert the assembled rod-shaped molded body inside the outer frame (the lower side of the burner tile is the opening side and the upper side is the outlet side of the furnace), and make sure that the straight bar is at the corner of the burner tile. The part that hits the torii legs on the bottom bottom was temporarily fixed with adhesive tape.
Furthermore, the truncated cone-shaped core for forming the opening was set upside down (the thick part was up and the thin part was down). Thereafter, a high alumina-based casting material was poured and shaken at 2 G for 1 minute. After being cured at room temperature for 1 day, it was deframed and further dried at about 300 ° C., and then used as a burner tile for a steel heating furnace.
Normally, after about half a year of use, a crack occurs and the burner tile exit side peels off. Cracks also occurred in the burner tile embedded with the rod-shaped molded body, but the width was about half that of the normal product, and the outlet side did not peel off.
[0043]
【The invention's effect】
According to the present invention, the lifetime of various refractories can be extended, and it can contribute to extending the lifetime of kilns and the like and reducing refractory costs.
[Brief description of the drawings]
FIG. 1 is a cylindrical refractory material in which rod-shaped molded bodies made of inorganic fibers are present radially.
FIG. 2 is a cylindrical refractory in which a rod-shaped molded body made of inorganic fibers is contained in parallel to the longitudinal direction.
FIG. 3 is a rod-like refractory material in which a rod-shaped molded body made of inorganic fibers is present in parallel to the longitudinal direction.
FIG. 4 is a cylindrical refractory in which a rod-shaped molded body made of inorganic fibers is annularly contained.
FIG. 5 is a cylindrical refractory in which a rod-shaped molded body made of inorganic fibers is spirally embedded.
FIG. 6 is a refractory material in which a molded body made of inorganic fibers is installed outside in parallel to the longitudinal direction.
FIG. 7 is a refractory material in which rod-shaped molded bodies made of inorganic fibers are annularly arranged outside.
FIG. 8 is a refractory material in which a rod-shaped molded body made of inorganic fibers is spirally installed outside.
FIG. 9 is a refractory material in which a rod-shaped molded body made of inorganic fibers is annularly installed on a part of the outside.
FIG. 10 is a refractory material in which a rod-shaped molded body made of inorganic fibers is annularly installed on a part of the outside.
[Figure11A schematic cross-sectional view after a rod-like refractory material containing a rod-shaped molded body made of inorganic fibers is immersed in the hot metal and repeatedly cooled. (A) is a sample in which a rod-shaped molded body is inherent, and (b) is a sample in which a rod-shaped molded body is not inherent.

Claims (9)

A refractory material reinforced with a rod-shaped molded body made of inorganic fibers having a diameter of 1 to 10 mm and a length of 10 mm or more, wherein the rod-shaped molded body uses a phenol resin as a binder and binds or twists inorganic fibers. Te or braided, or which Ri further moldings der took the pretension a bundle by bundling inorganic fibers or organic fibers, and said rod-shaped body parallel to a straight line in the longitudinal, circular or spiral Oh refractory reinforced with the rod shaped molded body comprising inorganic fibers, characterized in Rukoto. 2. The refractory reinforced with a rod-shaped molded body made of inorganic fibers according to claim 1, wherein the rod-shaped molded body is a rod-shaped molded body formed by applying tension to the inorganic fibers when the phenol resin is cured. .   3. A refractory reinforced with a rod-shaped molded body made of inorganic fibers according to claim 1, wherein the rod-shaped molded body is installed on a part or all of the outer periphery of the refractory.   The refractory reinforced with the rod-shaped molded body made of inorganic fibers according to any one of claims 1 to 3, wherein the rod-shaped molded body is installed inside the refractory. The refractory material reinforced with a rod-shaped formed body made of an inorganic fiber according to any one of claims 1 to 4 , wherein the inorganic fiber is a carbon fiber. The refractory reinforced with a rod-shaped formed body made of inorganic fibers according to any one of claims 1 to 5 , wherein the refractory is a lump-like, plate-shaped or rod-shaped refractory filled inside. Mass after heating for 3 hours at 600 ° C. embedded in coke powder, according to any one of claim 1 to 6, characterized in that the use of 5% or more rod-like molded product of the mass before heating A refractory reinforced with a rod-shaped body made of inorganic fibers. Assembling the rod shaped molded body in a mold, or the mold is placed around after assembling the rod-shaped body, any claim 1-7, characterized in pouring pouring the refractory into the subsequent mold A method for producing a refractory reinforced with a rod-shaped molded body made of an inorganic fiber according to claim 1. The refractory material poured into the mold is poured into the mold, and then the rod-shaped molded product is poured into the refractory material and reinforced with the rod-shaped molded product made of inorganic fibers according to any one of claims 1 to 7 . Refractory manufacturing method.

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