TWI752363B - hot fill material - Google Patents

Abstract

The purpose of the present invention is to improve the filling property of the hot filling material. The present invention provides a hot-filling material, which is a hot-filling material obtained by adding a binder and water to 100% by mass of the refractory raw material, wherein, in terms of the ratio of the above-mentioned 100% by mass of the refractory raw material, it contains 25% by mass or more and 60% by mass. % or less of basic raw materials with a particle size of 1 mm or more, and 5 mass% or more of 25 mass% or less of basic raw materials with a particle size of 20 μm or more and less than 106 μm, expressed as a ratio to 100 mass % of the aforementioned refractory raw materials. The content of basic raw materials having a diameter of less than 20 μm is 30 mass % or less (including 0).

Description

hot fill material

The present invention relates to hot fill materials.

Taking the replacement operation of the tap hole bushing of the converter as an example, the use form of the hot filling material will be explained. As shown in FIG. 1(A) , first, the converter 1 where the tapping is completed is tilted so that the tapping port 3 is brought close to the work floor 4 using the trunnion 2 as the axis. The operator disassembles the old bushing 6 through the circuit breaker 5 and removes it from the tap hole 3 . Next, as shown in FIG. 1(B) , the converter 1 is tilted with the trunnion 2 as the axis so that the tap hole 3 faces downward, and a new bushing 7 is inserted into the tap hole 3 . Next, the thermal filler 8 is ejected from the gap between the new bushing 7 and the main body of the converter 1 (hereinafter referred to as "construction target site") using the ejection device 9, and the construction object site is filled with the thermal filler 8.

The hot filling material 8 is made by adding a binder and water to the refractory raw material containing the alkaline raw material. In the example shown in FIG. 1(B) , the water system is added in the spouting pipe 10 of the spouting device 9 . The temperature of the construction target site is, for example, about 600 to 1000° C., and the hot filling material 8 boils immediately after filling. By this boiling force, the hot filling material 8 is stirred in the construction target site, and is densely filled in the construction object site. After boiling and stabilizing, the hot filling material 8 is hardened by the binding action of the adhesive (for example, refer to Patent Document 1).

Such thermal fillers are required to have fillability for the gaps in the construction target site as described above as their basic properties, but conventionally, the fillability cannot be said to be sufficient. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 4960906

[The problem to be solved by the invention]

The problem to be solved by the present invention is to improve the fillability of the hot filling material. [means to solve the problem]

Since the hot filling material is a gap filler, if it is hardened before filling the gap, the fillability will be deteriorated (the fillability of the gap cannot be ensured). Therefore, the present inventors focused on the results of repeated experiments and examinations on the particle size composition of the alkaline raw material constituting the hot-filling material, and found that if an appropriate amount of alkaline raw material with a particle size of 20 μm or more and less than 106 μm is included, the hot-filling The material easily fills the gap and hardens after filling the gap.

That is, according to one aspect of the present invention, the following thermal filling material is provided. A hot-filling material, which is a hot-filling material obtained by adding a binder and water to 100% by mass of a refractory raw material, In terms of the ratio of 100% by mass of the above-mentioned refractory raw materials, it contains 25% by mass to 60% by mass of basic raw materials with a particle size of 1 mm or more, and 5% by mass to 25% by mass. 106μm alkaline raw material, The content of the basic raw material whose particle size is less than 20 μm is 30 mass % or less (including 0) as a ratio to 100 mass % of the above-mentioned refractory raw material.

Moreover, in the present invention, the so-called particle size refers to the mesh size of the sieve when the refractory raw material particles are separated by sieving. The alkaline raw material having a particle size of 20 μm or more refers to an alkaline raw material that does not pass through a sieve with an opening of 20 μm. [Inventive effect]

According to the present invention, the filling property of the hot filling material can be improved.

The hot filling material of the present invention contains 5 to 25% by mass of basic raw materials with a particle size of 20 μm or more and less than 106 μm, expressed as a ratio to 100 mass % of the refractory raw materials. Alkaline raw materials dissolve out Mg ²⁺ ions or Ca ²⁺ ions, and the dissolved Mg ²⁺ ions or Ca ²⁺ ions react with binders to help harden the construction body. The 106 μm alkaline raw material has a moderate specific surface area, so Mg ²⁺ ions or Ca ²⁺ ions are eluted at a moderate rate of dissolution. Therefore, by containing an appropriate amount of the basic raw material having a particle size of 20 μm or more and less than 106 μm, the construction body can be hardened at an appropriate time. In addition, by containing an appropriate amount of the alkaline raw material having a particle size of 20 μm or more and less than 106 μm, the fluidity of the hot filling material is improved, and the gap can be easily filled. That is, the thermal filler containing 5 to 25% by mass of an alkaline raw material with a particle size of 20 μm or more and less than 106 μm is easy to fill in the gap, and it hardens after filling the gap, so the fillability of the gap is improved. . If the content of the alkaline raw material having a particle size of 20 μm or more and less than 106 μm is less than 5 mass %, the construction body may not be hardened or the hardening of the construction body may take a long time, which hinders the actual operation. On the other hand, if the content of the alkaline raw material having a particle size of 20 μm or more and less than 106 μm exceeds 25 mass %, the gap is temporarily filled, but the construction body is shrunk due to heat and the gap is regenerated. The content of the basic raw material having a particle size of 20 μm or more and less than 106 μm is preferably 10 mass % or more and 20 mass % or less.

The hot filling material of the present invention contains 25% by mass to 60% by mass of basic raw material with a particle size of 1 mm or more, expressed as a ratio to 100% by mass of the refractory raw material. When the content of the basic raw material with a particle size of 1 mm or more is less than 25% by mass, the balance of the particle size composition of the refractory raw material is deteriorated, and the strength of the construction body is lowered. On the other hand, when the content of the basic raw material having a particle size of 1 mm or more exceeds 60 mass %, the voids in the construction body increase, and the strength of the construction body is reduced on the contrary. The content of the basic raw material having a particle size of 1 mm or more is preferably 30 mass % or more and 50 mass % or less.

In the thermal filling material of the present invention, the content of the basic raw material having a particle size of less than 20 μm is 30 mass % or less (including 0). When the content of the alkaline raw material with a particle size of less than 20 μm exceeds 30 mass %, Mg ²⁺ ions or Ca ²⁺ ions are dissolved too quickly, and hardening occurs before filling into the gaps, so that uniform filling cannot be achieved. The content of the basic raw material having a particle size of less than 20 μm is preferably 20 mass % or less (including 0).

Moreover, the hot filling material of this invention may contain the alkaline raw material whose particle diameter is 106 micrometers or more and less than 1 mm, and may not contain it.

As the basic raw material, the basic raw material generally used in hot filling materials can be used, for example, magnesium oxide, dolomite, olivine, hydrotalcite, calcium carbonate, magnesium oxide-carbon and the like. Furthermore, the hot filling material of the present invention may include alumina, spinel, silicon carbide, alumina-silicon oxide, etc. as refractory raw materials other than basic raw materials.

_{In the hot filling material of the present invention, preferably, the total amount of SiO 2} and Fe ₂ O ₃ is 3.2 mass % or more and 7 mass % or less, and the content of Fe ₂ O ₃ is preferably 3.2 mass % or more, expressed as a ratio of 100 mass % of the refractory raw materials. The content is 1.5 mass % or less (including 0). SiO ₂ and Fe ₂ O ₃ form compounds with MgO or CaO in basic raw materials, and exert the effect of inhibiting the elution of ^{Mg 2+} ions and Ca ^{2+ ions.} Therefore, it is possible to suppress the early hardening of the construction body, increase the viscosity, and reduce the filling property. However, when _{the total amount of SiO 2} and Fe ₂ O ₃ is less than 3.2 mass %, the suppression of the elution of ^{Mg 2+} ions and Ca ^{2+ ions cannot be sufficiently exerted.} effect. On the other hand, _{when the total amount of SiO 2} and Fe ₂ O ₃ exceeds 7% by mass, ^{the moderate elution rate of Mg 2+} ions and Ca ²⁺ ions decreases, and hardening becomes difficult. The total amount of SiO ₂ and Fe ₂ O ₃ is more preferably 3.2 mass % or more and 5.5 mass % or less. Further, when the Fe ₂ O ₃ content exceeds 1.5 mass %, the formation of low melting point compounds may reduce corrosion resistance, so the Fe ₂ O ₃ content is preferably 1.5 mass % or less (including 0). Here, the Fe ₂ O ₃ content is obtained by detecting the amount of Fe in the sample by fluorescent X-ray analysis, and performing oxide conversion (Fe ₂ O ₃ ). Similarly, the _{content of SiO 2 is} determined by fluorescence X-ray analysis, and the amount of Si in the sample is detected and converted into oxide (SiO ₂ ).

The hot filling material of the present invention is obtained by adding a binder and water to 100% by mass of the above-mentioned refractory raw materials. As a binder, those commonly used in hot-fill materials can be used, such as phosphates, silicates, asphalt, powder resins, alumina cement, etc., but typically at least one selected from phosphates and silicates is used. one kind. Examples of the phosphate include sodium phosphate, potassium phosphate, lithium phosphate, calcium phosphate, magnesium phosphate, aluminum phosphate, and the like, and examples of the silicate include sodium silicate, potassium silicate, calcium silicate, and the like. In addition, the addition amount of the binder may also be the same as that of a general hot filling material, for example, with respect to 100 mass % of the refractory raw material, 1 mass % or more and 10 mass % or less are added. Moreover, an additive can also be used for an adhesive agent. Various additives such as hardeners, dispersants, and tackifiers can be used as additives. For example, slaked lime can be used as a hardener, phosphate can be used as a dispersant, and clay can be used as a tackifier.

The addition amount of water may also be the same as that of general hot filling materials, for example, with respect to 100 mass % of refractory raw materials, plus 30 mass % or more and 60 mass % or less.

As described above, the hot filling material of the present invention can be sprayed with air using the spraying device 9 shown in FIG. [Example]

In Table 1 and Table 2, the composition and evaluation results of the refractory raw materials of Examples and Comparative Examples of the present invention are shown. In Tables 1 and 2, magnesium oxide was used as the "basic raw material" except in Example 8, and in Example 8, magnesium oxide and dolomite were used in combination. Evaluation items and evaluation methods are as follows.

＜Fillability＞ The hot filling materials of each example obtained by adding an appropriate amount of binder (sodium phosphate) and water to the refractory raw materials of each example shown in Table 1 and Table 2 were used in the tile-making group 11 (4 magnesia- In the gap 12 of the quadrangular pyramid shape of 15 mm square x 230 mm formed by the combination of carbon smelting tiles 11a), the smelting tile group 11 was heated to 1000°C and flowed. After cooling, the tile set 11 was cut off, and the fillability of the gap 12 (the size of the unfilled gap) was confirmed. Fillability evaluation When there is no unfilled gap or the size of the unfilled gap is less than 1mm, it is marked as ○ (good), and the case where the size of the unfilled gap is more than 1mm and less than 2mm is marked as △ (ok). The case where the size of the gap to be filled was 2 mm or more was denoted as × (poor).

＜Strength of construction body＞ The hot filling material of each example obtained by adding an appropriate amount of binder (sodium phosphate) and water to the refractory raw materials of each example shown in Table 1 and Table 2 was poured into a mold frame heated to 1000°C, boiled, hardened and cooled. After reaching normal temperature, the construction body was taken out from the mold frame, and the size of 40 mm×40 mm×160 mm was cut out from the construction body as a test piece, and the flexural strength was measured according to JIS-R2575 for other conditions. The flexural strength of each example was divided by the flexural strength of Comparative Example 1 and multiplied by 100 times as a flexural strength index. The larger the bending strength index, the higher the strength of the construction body. In the evaluation of the strength of the construction body, when the flexural strength index exceeded 110, it was rated as ○ (good), when it was more than 100 and less than 110, it was rated as Δ (acceptable), and when it was less than 100, it was rated as × (poor).

＜Denseness＞ The apparent porosity of the aforementioned construction body is measured in accordance with JIS-R2205-1992. The apparent porosity of each example was divided by the apparent porosity of Comparative Example 1 and multiplied by 100 times as the apparent porosity index. The smaller the apparent porosity index, the higher the compactness of the construction body. In the evaluation of compactness, when the apparent porosity index was 90 or less, it was rated as ○ (good), when it was more than 90 and less than 100, it was rated as Δ (good), and when it was more than 100, it was rated as × (poor).

(resistance to slag infiltration) In a rotary erosion test device, converter slag was used as an etchant, and the maximum slag infiltration depth was measured when the test piece cut out from the construction body was eroded at 1650° C. for 5 hours. The value of the maximum slag infiltration depth of each example divided by the maximum slag infiltration depth of Comparative Example 1 and multiplied by 100 times was set as the slag infiltration depth index. The smaller the slag infiltration depth index, the higher the resistance to slag infiltration. In the evaluation of slag infiltration resistance, when the slag infiltration depth index was 90 or less, it was rated as ○ (good), when it was more than 90 and less than 100, it was rated as △ (good), and when it was more than 100, it was rated as × (poor).

＜Comprehensive evaluation＞ In each of the above-mentioned evaluations, when all were ○, it was rated as ○ (good), when there was no x and any one was rated as Δ, it was rated as Δ (possible), and when any one was rated as x, it was rated as x (poor).

Examples 1 to 11 are hot filling materials within the scope of the present invention. Any comprehensive evaluation was ○ (good) or Δ (fair), and good results were obtained.

Comparative Example 1 is an example in which the content of basic raw materials having a particle size of 20 μm or more and less than 106 μm is small. The construction body was not sufficiently hardened, and all the evaluations were x (unsatisfactory). Comparative Example 2 is an example in which the content of basic raw materials having a particle size of 20 μm or more and less than 106 μm is large. The filling property was evaluated as × (poor).

Comparative Example 3 is an example in which the content of basic raw materials having a particle size of 1 mm or more is small. The evaluation of the strength of the construction body was × (poor). Comparative Example 4 is an example in which the content of basic raw materials having a particle size of 1 mm or more is large. The more voids in the construction body, the lower the density, and the lower the strength of the construction body and the resistance to slag infiltration. In addition, since the content of the basic raw material in coarse particles having a particle diameter of 1 mm or more is large, the filling property of the gap is also lowered.

Comparative Example 5 is an example in which the content of the basic raw material having a particle size of less than 20 μm is large. The filling property was evaluated as × (poor).

1: Converter 2: Trunnion 3: steel outlet 4: Working floor 5: Circuit breaker 6: old bushing 7: New bushing 8: Hot filling material 9: ejection device 10: Ejection tube 11: Refining tile group 11a: Magnesium oxide-carbon tile 12: Gap

[Fig. 1] is a diagram showing a usage form of a hot filling material. [Fig. 2] shows the tile set used for the evaluation of fillability.

1: Converter

2: Trunnion

3: steel outlet

4: Working floor

5: Circuit breaker

6: old bushing

7: New bushing

8: Hot filling material

9: ejection device

10: Ejection tube

Claims (5)

A hot-filling material, which is a hot-filling material obtained by adding a binder and water to 100% by mass of the refractory raw material, and contains 25% by mass to 60% by mass, expressed as a ratio to 100% by mass of the aforementioned refractory raw material. Basic raw materials with a particle size of 1 mm or more, 5 mass % or more and 25 mass % or less of basic raw materials with a particle size of 20 μm or more and less than 106 μm, expressed as a ratio to 100 mass % of the aforementioned refractory raw materials, the particle size is less than 20 μm. The basic raw material content of 20 μm is 30 mass % or less (including 0). The hot filling material according to claim 1, which, expressed as a ratio of 100% by mass of the aforementioned refractory raw materials, contains 30% by mass to 50% by mass of alkaline raw materials with a particle size of 1 mm or more, 10% by mass or more and 20% by mass % or less of basic raw materials with a particle size of 20 μm or more and less than 106 μm, expressed as a ratio of 100% by mass of the aforementioned refractory raw materials, the content of basic raw materials with a particle size of less than 20 μm is 20 mass % or less (including 0) . The hot filling material according to claim 1 or 2, wherein _{the total amount of SiO 2} and Fe ₂ O ₃ is 3.2 mass % or more and 7 mass % or less, and Fe ₂ The O ₃ content is 1.5 mass % or less (including 0). The hot filling material according to claim 1 or 2, wherein _{the total amount of SiO 2} and Fe ₂ O ₃ is 3.2 mass % or more and 5.5 mass % or less, and Fe ₂ The O ₃ content is 1.5 mass % or less (including 0). The hot-fill material of claim 1, wherein the aforementioned bonding The agent contains at least one selected from phosphates and silicates.

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