Spraying material for simple wet spraying construction equipment

Abstract

To provide a spraying material for a simple wet spraying construction device, which has improved transportability and adhesion. The system comprises a cutting section (11) that receives a spraying material (A) containing a refractory material and a binder and continuously cuts out the spraying material (A), a water injection section (12) that adds water (B) to the spraying material (A) cut out from the cutting section (11), a kneading section (13) that kneads the water (B) added from the water injection section (12) with the spraying material (A), and a pressure-feeding section (14) that pressure-feeds the kneaded material (C) continuously supplied from the kneading section (13) to a spray nozzle (16) through a conveying hose (15) using compressed air (D). The spraying material A is for a simple wet spraying construction device 1 having the above structure, and the particle size composition of the fire-resistant material in the spraying material A is such that coarse particles with a particle size of 1 mm or more and less than 3 mm account for 30% by mass or less (including 0), medium particles with a particle size of 0.075 mm or more and less than 1 mm account for 40% by mass or more and 70% by mass or less, and fine particles with a particle size of less than 0.075 mm account for 20% by mass or more and 50% by mass or less, and the addition rate of water B added in the water injection section 12 is 20% by mass or more and 40% by mass or less.

Description

[Technical Field]

[0001] The present invention relates to a spraying material used in a simple wet spraying construction device. [Background technology]

[0002] Spraying is used as a means of forming or repairing linings for molten metal containers, high-temperature furnaces, molten metal processing equipment, and the like. Spraying can be broadly divided into wet spraying and dry spraying. Among these spraying methods, wet spraying generally involves adding water to a spraying material prepared in advance as a slurry, pressure-feeding the material to a spray nozzle through a conveying hose using a pressure pump, and adding a quick-setting agent in the spray nozzle or conveying hose before spraying (see, for example, Patent Documents 1 and 2). In this general wet spraying method, a slurry-like spraying material is prepared in advance, pressure-feeding the slurry-like spraying material to a spray nozzle using a pressure pump such as a squeeze pump, and then adding a quick-setting agent in the spray nozzle or conveying hose before spraying.

[0003] On the other hand, there is a simple wet spraying technique in which a series of processes from preparing a slurry-like spraying material to spraying is carried out using a single wet spraying device, known as simple wet spraying. This simple wet spraying device has a cutting section that receives the spraying material and continuously cuts it out, a water injection section that adds water to the spraying material cut out from the cutting section, a kneading section that kneads the water added from the water injection section with the spraying material, and a pressure-feeding section that pressure-feeds the kneaded material continuously supplied from the kneading section through a conveying hose to a spray nozzle using compressed air (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-115082 [Patent Document 2] Patent Publication No. 2021-161004 [Patent Document 3] Japanese Patent Application Laid-Open No. 2000-46479 Summary of the Invention [Problem to be solved by the invention]

[0005] When the inventor conducted tests on simple wet spraying construction, he found that due to circumstances unique to simple wet spraying construction equipment, such as the fact that mixing in the mixing section is continuous and short, and that the spraying material is pressurized using compressed air, there are problems with the transportability of the spraying material within the conveying hose, and there are also problems with the adhesion of the spraying material to the surface to be applied.

[0006] Therefore, the problem that the present invention aims to solve is to improve the transportability and adhesion of spraying materials in simple wet spraying construction, and more specifically, to provide a spraying material for simple wet spraying construction equipment that has improved transportability and adhesion. [Means for solving the problem]

[0007] As a result of repeated testing of simple wet spraying construction, the inventors discovered that in order to improve the transportability and adhesion of the spraying material in simple wet spraying construction, it is essential to control the particle size composition of the refractory material in the spraying material as well as to control the rate of water added to the spraying material.

[0008] That is, according to one aspect of the present invention, there is provided the following spraying material for a simple wet spraying construction device. A spraying material for a simple wet spraying device, which is used in a simple wet spraying device having a cutting section that receives a spraying material containing a refractory material and a binder and continuously cuts out the spraying material, a water injection section that adds water to the spraying material cut out from the cutting section, a kneading section that kneads the water added from the water injection section with the spraying material, and a pressure-feeding section that pressure-feeds the kneaded material continuously supplied from the kneading section to a spray nozzle through a conveying hose using compressed air, The spraying material includes a refractory material and a binder, The above-mentioned in the spraying materialThe particle size composition of the refractory material is 30% by mass or less (including 0) of coarse particles with a particle size of 1 mm or more and less than 3 mm, 40% by mass or more and less than 70% by mass of medium particles with a particle size of 0.075 mm or more and less than 1 mm, and 20% by mass or more and less than 50% by mass of fine particles with a particle size of less than 0.075 mm, The rate of water added in the water injection section is , the outer percentage of the total 100% of the sprayed material A spraying material for a simple wet spraying construction device, which is 20% by mass or more and 40% by mass or less. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a spraying material for a simple wet spraying construction device that has improved transportability and adhesion, thereby improving the transportability and adhesion of the spraying material in simple wet spraying construction. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a conceptual diagram showing the configuration of a simple wet spraying construction device. DETAILED DESCRIPTION OF THE INVENTION

[0011] First, the configuration of a simple wet spraying construction device that uses the spraying material of the present invention will be described. Figure 1 is a conceptual diagram showing the configuration of a simple wet spraying construction device. As shown in the figure, the simple wet spraying construction device 1 has a cutting section 11 that receives spraying material A and continuously cuts out this spraying material A, a water injection section 12 that adds water B to the spraying material A cut out from the cutting section 11, a kneading section 13 that kneads the water B added from the water injection section 12 with the spraying material A, and a pressure-transfer section 14 that pressure-transfers the kneaded material C continuously supplied from the kneading section 13 to the spray nozzle 16 through a conveying hose 15 using compressed air D.

[0012] The spraying material A is supplied from outside and contains a refractory material and a binder. In order to solve the above-mentioned problems, the first technical feature of the present invention is that the particle size composition of the refractory material in the spraying material A is controlled. That is, in the present invention, the particle size composition of the refractory material in the spraying material A is such that coarse particles with a particle size of 1 mm or more and less than 3 mm account for 30% by mass or less (including 0), medium particles with a particle size of 0.075 mm or more and less than 1 mm account for 40% by mass or more and 70% by mass or less, and fine particles with a particle size of less than 0.075 mm account for 20% by mass or more and 50% by mass or less. If the coarse particles exceed 30% by mass, the proportion of the coarse particles in the kneaded material C becomes too large, which makes it easier for segregation (hereinafter simply referred to as "segregation"), in which particles in the kneaded material C segregate, resulting in a decrease in conveyability.Furthermore, the decrease in conveyability also decreases adhesion. If the medium grain content is less than 40% by mass, the proportion of coarse or fine grains will be relatively high, making segregation more likely to occur, and the back pressure on the pumping section 14 will increase, reducing conveyability and adhesion. If the medium grain content is more than 70% by mass, segregation will also be more likely to occur, reducing conveyability and adhesion. If the fine particles are less than 20% by mass, the kneaded material C will not have enough cohesive power at the moment of adhering to the surface to be applied, resulting in reduced adhesion. On the other hand, if the fine particles are more than 50% by mass, the kneaded material C will have too strong cohesive power, which will increase the back pressure on the pumping section 14, resulting in reduced transportability and adhesion.

[0013] Here, in the present invention, the particle size of a refractory material refers to the size of the sieve openings when the refractory material is sieved to separate particles. For example, a refractory material with a particle size of less than 1 mm is a refractory material that passes through a sieve with 1 mm openings, and a refractory material with a particle size of 1 mm or more is a refractory material that does not pass through a 1 mm sieve opening.

[0014] A second technical feature of the present invention is that the addition rate of water B added to the spraying material A is controlled. That is, the second technical feature of the present invention is that the addition rate of water B added in the water injection section 12 is set to 20% by mass or more and 40% by mass or less. If the addition rate of water B is less than 20% by mass, the viscosity of the kneaded material C becomes high, increasing the back pressure on the pumping section 14, thereby reducing transportability and adhesiveness. On the other hand, if the addition rate of water B exceeds 40% by mass, the amount of water in the kneaded material C becomes excessive, weakening cohesiveness and reducing adhesiveness.

[0015] The effects of improving the transportability and adhesion due to the above-described technical features of the present invention are particularly pronounced when the length of the transport hose 15 is 10 m or more. This is because problems with transportability and adhesion become particularly apparent when the length of the transport hose 15 is 10 m or more.

[0016] The technical features of the present invention are as described above. The types and blending ratios of the refractory material and binder constituting the spraying material A are not particularly limited and may be the same as those of conventional spraying materials. For example, various refractory materials such as magnesia, alumina, and silica can be used as the refractory raw material, and various binders such as phosphates, silicates, and cement can also be used as the binder. The blending ratios of the refractory material and binder may also be the same as those of conventional spraying materials. Furthermore, in addition to the above-mentioned refractory material and binder, the spraying material of the present invention may contain various additives such as dispersants, hardening adjusters, fibers, and thickeners. The content ratios thereof may also be the same as those of conventional spraying materials. [Example]

[0017] Table 1 shows the configurations of the spraying materials of the examples of the present invention and comparative examples, as well as the evaluation results of the transportability and adhesion of the spraying materials of each example. Transportability and adhesion were evaluated by conducting a spraying test using the simple wet spraying construction device 1 shown in Figure 1. In the spraying test of the spraying materials of each example, the addition rate of water added in the water injection section 12 is as shown in Table 1. The length of the transport hose 15 was 10 m. Conveyance was evaluated based on the discharge status of the kneaded material C (a mixture of spray material A and water B transported by compressed air D) discharged from the spray nozzle 16 in the spray test. That is, if there was no pulsation of the kneaded material C and the discharge status was stable, it was evaluated as ○ (excellent), if pulsation occurred several times it was evaluated as △ (good), and if pulsation occurred frequently it was evaluated as × (poor), with ○ or △ being considered a pass. The adhesion was evaluated based on the adhesion rate of the kneaded product C to the application surface. That is, an adhesion rate of 80% or more was evaluated as ○ (excellent), an adhesion rate of 60% or more but less than 80% was evaluated as △ (good), and an adhesion rate of less than 60% was evaluated as × (bad), with ○ or △ being considered a pass.

[0018] [Table 1]

[0019] In Examples 1 and 2, the proportion of coarse particles in the particle size composition of the refractory material in the spraying material A was changed, but both were within the range of the present invention and both the transportability and adhesion were at acceptable levels. In contrast to this, Comparative Example 1 is an example in which the proportion of coarse particles exceeds the upper limit of the present invention, and the transportability deteriorated, and the adhesiveness also deteriorated accordingly.

[0020] , In Examples 3 and 4, the proportion of medium particles in the particle size composition of the refractory material in the spraying material A was changed, but both were within the range of the present invention and both transportability and adhesion were at acceptable levels. In contrast, Comparative Example 2 is an example in which the proportion of medium particles is below the lower limit of the present invention, and conveyance performance and adhesion performance accordingly declined. Comparative Example 3 is an example in which the proportion of medium particles is above the upper limit of the present invention, and conveyance performance and adhesion performance accordingly declined.

[0021] In Examples 5 and 6, the proportion of fine particles in the particle size composition of the refractory material in the spraying material A was changed, but both were within the range of the present invention and both the transportability and adhesion were at acceptable levels. In contrast, Comparative Example 4 is an example in which the proportion of fine particles is below the lower limit of the present invention, and the adhesiveness was reduced.Comparative Example 5 is an example in which the proportion of fine particles is above the upper limit of the present invention, and the transportability and adhesiveness were reduced.

[0022] In Examples 7 and 8, the water addition ratio was changed, but both were within the range of the present invention, and both the transportability and adhesion were at acceptable levels. In contrast, Comparative Example 6 is an example in which the water content is below the lower limit of the present invention, and conveyability and adhesion were reduced. Comparative Example 7 is an example in which the water content is above the upper limit of the present invention, and adhesion was reduced.

[0023] In Examples 9 and 10, the type of binder was changed, but both were within the scope of the present invention, and both transportability and adhesion were at acceptable levels. Here, from a comparison between Examples 9 and 10, it can be said that it is preferable to use one or more types selected from phosphates and silicates as the binder. [Explanation of symbols]

[0024] 1 Simple wet spraying construction device 11 Cutout part 12 Water injection section 13 Mixing section 14 Pressure feed section 15 Conveying hose 16 spray nozzle A spray material B water C. Kneaded material D. Compressed air

Claims

[Claim 1] A spraying material for a simple wet spraying device, which is used in a simple wet spraying device having a cutting section that receives a spraying material containing a refractory material and a binder and continuously cuts out the spraying material, a water injection section that adds water to the spraying material cut out from the cutting section, a kneading section that kneads the water added from the water injection section with the spraying material, and a pressure-feeding section that pressure-feeds the kneaded material continuously supplied from the kneading section to a spray nozzle through a conveying hose using compressed air, The spraying material includes a refractory material and a binder, The particle size composition of the fire-resistant material in the spraying material is such that coarse particles having a particle size of 1 mm or more and less than 3 mm account for 30% by mass or less (including 0), medium particles having a particle size of 0.075 mm or more and less than 1 mm account for 40% by mass or more and 70% by mass or less, and fine particles having a particle size of less than 0.075 mm account for 20% by mass or more and 50% by mass or less, A spraying material for a simple wet spraying construction device, wherein the rate of water added in the water injection section is 20% by mass or more and 40% by mass or less, based on a total of 100% by mass of the spraying material.

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