How to install precast refractory blocks for coke ovens

Abstract

To provide a method for installing precast refractory blocks for coke ovens that can accurately position and install precast refractory blocks lifted by a lifting tool at a predetermined installation position.SOLUTION: A method for installing precast refractory blocks for coke ovens includes: a step of drawing a vertical reference line 7 on the inner side surface 6a-1 of a backstay 6a installed on one side of the coke oven in the oven length direction; a step of applying laser light 8 from the other side of the coke oven in the oven length direction so as to overlap the vertical reference line; a step pf drawing a marking-off line 11 in the oven length direction on the top surface 10A-1 of the first precast refractory block 10A, and drawing a marking-off line 12 in the oven height direction on the other side surface 10A-2 of the first precast refractory block 10A so as to be continuous with the marking-off line 11 in the oven length direction; and a step of installing the first precast refractory block 10A so that the laser light 8 overlaps the marking-off line 11 in the oven length direction and the marking-off line 12 in the oven height direction.SELECTED DRAWING: Figure 5A

Description

[Technical Field]

[0001] The present invention relates to a method for installing precast refractory blocks for a coke oven. [Background technology]

[0002] In coke ovens, also known as chamber-hearth coke ovens, coke chambers and combustion chambers are arranged alternately across the width of the oven, with the furnace top located above the coke chambers and combustion chambers and the regenerators below. The area between the combustion chamber and the regenerator is also called the bellows. A sole flue is located below the regenerator. The dimensions of a coke chamber are typically approximately 4 to 7.5 m in height, 350 to 550 mm in width, and 13 to 17 m in length. The combustion chamber consists of a row of combustion chamber flues arranged along the length of the oven. The partitions between the coke chamber and combustion chamber, the partitions between the combustion chamber flues, the furnace top, the bellows, the regenerators, and the sole flue are all formed as refractory structures.

[0003] The refractory structures in these coke ovens are mostly constructed with silica bricks, due to their high mechanical strength in high-temperature regions, minimal volume change, relatively good thermal conductivity, and the low cost and large-scale availability of the material. Silica bricks used as refractories are fired bricks made by firing raw silica. They are 100–150 mm high, with lengths and widths determined by the shape of the combustion chamber flue, for example, and weigh just under 20 kg each. The refractory structures are constructed by applying mortar to the joints between the bricks. For example, a coke oven with 50 carbonization chambers would use a total of one million silica bricks to construct the refractory structures.

[0004] When building a new coke oven or when updating the entire refractory structure of an aging coke oven, the manual construction method is used, in which silica bricks are laid one by one by hand. This method is carried out by kiln builders, who are specialized bricklayers. Coke ovens are installed within steelworks premises and produce coke to be used in the steelworks' blast furnaces. Therefore, when upgrading existing coke ovens, it is necessary to procure coke through other means during the shutdown period for the upgrade, so it is necessary to shorten the shutdown period for the upgrade as much as possible. Since the work of laying silica bricks using the hand-laid method is entirely done by hand, shortening the construction period requires the work of a large number of skilled furnace builders. However, since the number of skilled furnace builders is limited, it is difficult to secure a sufficient number of furnace builders to complete the construction in a short period of time. Furthermore, furnace construction using the hand-laid method is labor-intensive, and as mentioned above, the builders are required to have highly skilled techniques, so it is expected that it will become even more difficult to secure furnace builders in the future.

[0005] Therefore, in recent years, in order to construct coke ovens with a small number of workers, a method of constructing coke ovens by sequentially installing large precast refractory blocks has been adopted (for example, Patent Document 1). In this method, it is necessary to lift the large precast refractory blocks with a lifting tool, move them to the predetermined installation position, and accurately position and install them at that installation position. Specifically, installation accuracy must be within ±2 mm in all directions, namely, the furnace width direction X, the furnace length direction Y, and the furnace height direction Z. However, it has been difficult to accurately position and install the precast refractory blocks lifted with a lifting tool at the predetermined installation position. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-8197 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide a method for installing precast refractory blocks for coke ovens, which can accurately position and install precast refractory blocks lifted by a lifting tool at a predetermined installation position. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the inventors came up with the idea of ​​using the backstays installed on the outside of the coke oven at both ends in the furnace length direction as the absolute reference for positioning when installing precast refractory blocks, and further drawing marking lines on the precast refractory blocks and using laser light to position them, thereby conceiving the present invention.

[0009] That is, according to one aspect of the present invention, there is provided the following method for installing precast refractory blocks for a coke oven. a step of drawing a vertical reference line on a furnace-inside side surface of a backstay installed on one side in the furnace length direction of the coke oven; irradiating the coke oven with a laser beam from the other side in the furnace length direction so as to overlap the vertical reference line; a step of drawing a furnace length direction marking line on the top surface of a first precast refractory block installed adjacent to the furnace inside side surface of the backstay, and drawing a furnace height direction marking line on the other side surface that faces the other side of the coke oven in the furnace length direction when installing the first precast refractory block so that the marking line is continuous with the furnace length direction marking line; and installing the first precast refractory block so that the laser light overlaps the furnace length direction marking line and the furnace height direction marking line. [Effects of the Invention]

[0010] According to the method for installing a precast refractory block for a coke oven of the present invention, the precast refractory block lifted by the lifting tool can be accurately positioned and installed at a predetermined installation position. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view conceptually showing the structure of a coke oven. [Figure 2A] FIG. 1 is a perspective view conceptually showing the arrangement of retaining walls and backstays of a coke oven. [Figure 2B] FIG. 1 is a schematic plan view conceptually showing the arrangement of retaining walls and backstays of a coke oven. [Figure 3A] FIG. 10 is a perspective view conceptually showing the process of drawing a vertical reference line on the furnace-inside side of a backstay installed on one side of the coke oven in the furnace length direction. [Figure 3B] FIG. 10 is a perspective view conceptually showing a process of irradiating a laser beam from the other side of the coke oven in the furnace length direction so as to overlap with a vertical reference line. [Figure 4] FIG. 1 is a perspective view conceptually showing the process of drawing furnace length direction marking lines and furnace height direction marking lines on the first precast refractory block. [Figure 5A] FIG. 10 is a perspective view conceptually showing the process of installing a first precast refractory block adjacent to the furnace-inside side of the backstay (in the middle of installation). [Figure 5B] Schematic plan view conceptually showing the process of installing the first precast refractory block adjacent to the furnace-inside side of the backstay (in the middle of installation). [Figure 6A] FIG. 10 is a perspective view conceptually showing the process of installing a first precast refractory block adjacent to the furnace-inside side of the backstay (installation completed state). [Figure 6B] Schematic plan view conceptually showing the process of installing the first precast refractory block adjacent to the furnace-inside side of the backstay (after installation is completed). [Figure 7A] FIG. 10 is a perspective view conceptually showing the process of installing a second precast refractory block adjacent to the other side surface of the first precast refractory block (in the middle of installation). [Figure 7B] 10 is a schematic plan view conceptually showing the process of installing a second precast refractory block adjacent to the other side surface of the first precast refractory block (in the middle of installation). FIG. [Figure 8A]FIG. 10 is a perspective view conceptually showing the process of installing a second precast refractory block adjacent to the other side surface of the first precast refractory block (installation completed state). [Figure 8B] 10 is a schematic plan view conceptually showing the process of installing a second precast fire-resistant block adjacent to the other side surface of the first precast fire-resistant block (after installation is completed). [Figure 9] FIG. [Figure 10A] This is an oblique view conceptually showing the state before the upper precast refractory block is installed on top of the second precast refractory block in the process of installing the upper precast refractory block on top of the first tier of precast refractory blocks including the second precast refractory block. [Figure 10B] A schematic plan view conceptually showing the state before the upper precast refractory block is installed on top of the second precast refractory block in the process of installing the upper precast refractory block on top of the first tier of precast refractory blocks including the second precast refractory block. [Figure 11A] FIG. 10 is a perspective view conceptually showing the process of applying mortar 14 to the upper surface of the second precast refractory block. [Figure 11B] FIG. 10 is a schematic plan view conceptually showing the process of applying mortar 14 to the upper surface of the second precast refractory block. [Figure 12A] This is a perspective view conceptually showing the process of installing the upper precast refractory block on top of the second precast refractory block (in the middle of installation). [Figure 12B] A schematic plan view conceptually showing the process of installing the upper precast refractory block on top of the second precast refractory block (in the middle of installation). [Figure 13A] A perspective view conceptually showing the process of installing the upper precast refractory block on top of the second precast refractory block (installation completed). [Figure 13B] A schematic plan view conceptually showing the process of installing the upper precast refractory block on top of the second precast refractory block (after installation is complete). DETAILED DESCRIPTION OF THE INVENTION

[0012] Fig. 1 conceptually shows the structure of a coke oven, and Fig. 2A and Fig. 2B conceptually show the arrangement of the retaining walls and backstays of the coke oven. In the coke oven A, the coking chambers 1 and the combustion chambers 2 are arranged alternately in the oven width direction X, with the oven top 3 above the coking chambers 1 and the combustion chambers 2 and the regenerators 4 below. Concrete retaining walls 5 are provided at both ends in the oven width direction X, and serve to retain the refractory structure between the two retaining walls 5, 5. In addition, backstays 6a, 6b are installed facing each other on the outside of the oven at both ends in the oven length direction Y of the coke oven A to apply oven clamping force to the refractory structure.

[0013] Using the construction of a coke oven A having such a structure as an example, an embodiment of the method of installing a precast refractory block for a coke oven according to the present invention will be described below. Here, the precast refractory block is a refractory block obtained by adding water to a granular refractory composition, kneading the mixture, pouring it into a formwork, and drying it. Typical precast refractory blocks for coke ovens include fused silica precast refractory blocks and clay precast blocks. The fused silica precast refractory block is a precast refractory block obtained by blending fused silica as the main raw material in the raw material composition of the refractory composition. The clay precast refractory block is a precast refractory block obtained by blending chamotte as the main raw material in the raw material composition of the refractory composition. In the following description, the "precast refractory block for coke oven" will be simply referred to as the "precast refractory block."

[0014] In this embodiment, as shown in FIG. 3A, a vertical reference line 7, which is a reference line extending vertically, is drawn on the furnace-inside side surface 6a-1 of the backstay 6a installed on one side in the furnace longitudinal direction Y of the coke oven. This vertical reference line 7 is usually drawn at the center of the furnace-inside side surface 6a-1, but is not necessarily limited to the center of the furnace-inside side surface 6a-1. In short, it is sufficient to draw the vertical reference line 7 on the furnace-inside side surface 6a-1. Furthermore, considering the installation accuracy of within ±2 mm mentioned above, it is preferable that the line width of the vertical reference line 7 be 2 mm or less. In this embodiment, the backstay 6a installed on one side of the coke oven in the furnace longitudinal direction Y is used as the absolute reference for positioning when installing precast refractory blocks. The backstay 6a is fixed to the ground and does not move, making it suitable as an absolute reference for positioning.

[0015] Next, as shown in Fig. 3B, a laser beam 8 is applied from the other side of the coke oven in the furnace length direction Y so as to overlap with the vertical reference line 7. Specifically, in this embodiment, a laser oscillator 9 that oscillates a slit-shaped laser beam 8 is installed on the furnace inside side surface 6b-1 of a backstay 6b installed on the other side of the coke oven in the furnace length direction Y, so that the laser beam 8 is applied from the other side of the coke oven in the furnace length direction Y so as to overlap with the vertical reference line 7. In Fig. 3B, the irradiation range of the slit-shaped laser beam 8 is indicated by a dashed line. Considering the installation accuracy of ±2 mm mentioned above, the slit width, i.e., line width, of the slit-shaped laser beam 8 is preferably 2 mm or less, similar to the line width of the vertical reference line 7. The type of laser beam 8 is not particularly limited, but visible light is used if it is assumed that a worker will be involved in the installation of the precast refractory blocks. On the other hand, if the installation of the precast refractory blocks is performed automatically using a robot arm or the like, the laser beam 8 does not have to be visible light. As described above, in this embodiment, the laser oscillator 9 is installed on the backstay 6b installed on the other side of the coke oven in the furnace length direction Y, and the laser beam 8 is irradiated from the other side of the coke oven in the furnace length direction Y so as to overlap with the vertical reference line 7. This laser beam 8 serves as a reference for positioning when installing precast refractory blocks, as will be described later. Therefore, it is desirable that the irradiation range of the laser beam 8 does not move. In this regard, in this embodiment, the laser oscillator 9 is installed on the backstay 6b, which is fixed to the ground and does not move, similar to the above-mentioned backstay 6a, so the irradiation range of the laser beam 8 does not move. As described above, in the present invention, it is preferable that a laser beam source such as the laser oscillator 9 is installed on the backstay installed on the other side of the coke oven in the furnace length direction.

[0016] Next, as shown in Figures 5A and 5B and 6A and 6B, a step of installing a first precast refractory block 10A adjacent to the furnace-inside side surface 6a-1 of the backstay 6a is carried out. However, before carrying out this step, a step of drawing a furnace-length-direction scribing line 11 and a furnace-height-direction scribing line 12 on the first precast refractory block is carried out as shown in Figure 4. Specifically, the furnace-length-direction scribing line 11, which is a scribing line extending in the furnace-length direction Y, is drawn on the top surface 10A-1 of the first precast refractory block 10A, which is installed adjacent to the furnace-inside side surface 6a-1 of the backstay 6a. In addition, when installing the first precast refractory block 10A, a furnace-height-direction scribing line 12, which is a scribing line extending in the furnace-height direction Z so as to be continuous with the furnace-length-direction scribing line 11, is drawn on the other side surface 10A-2, which is the side surface facing the other side of the coke oven in the furnace-length direction Y. In Figure 4, the furnace length direction marking line 11 and the furnace height direction marking line 12 are shown as dashed lines for convenience, but in reality they are solid lines. The same applies to Figure 4 and subsequent figures. However, the furnace length direction marking line 11 and the furnace height direction marking line 12 may also be dashed lines. Here, considering the installation accuracy of within ±2 mm mentioned above, it is preferable that the line width of the furnace length direction marking line 11 and the furnace height direction marking line 12 be 2 mm or less, similar to the line width of the vertical reference line 7. Four suspender rings 13 for connecting with suspenders (not shown) are detachably attached to the top surface 10A-1 of the first precast fire-resistant block 10A.

[0017] Next, as shown in Figures 5A and 5B and 6A and 6B, the first precast refractory block 10A is placed adjacent to the furnace-inside side surface 6a-1 of the backstay 6a. Specifically, as shown in Figures 5A and 5B, the position and posture of the first precast refractory block 10A are adjusted so that the laser beam 8 overlaps the furnace-length direction marking line 11 and the furnace-height direction marking line 12 drawn on the top surface 10A-1 and the other side surface 10A-2 of the first precast refractory block 10A lifted by a lifting device (not shown). Finally, as shown in Figures 6A and 6B, the first precast refractory block 10A is placed adjacent to the furnace-inside side surface 6a-1 of the backstay 6a. As shown in Figs. 5A and 5B, mortar 14 is applied in advance to the positions where the first precast refractory blocks 10A are to be installed.

[0018] After the first precast refractory block 10A is installed in this manner, the second precast refractory block 10B is installed adjacent to the other side surface 10A-2 of the first precast refractory block 10A, as shown in Figures 7A and 7B and 8A and 8B. However, before this step, a spacer 15 is attached to the other side surface 10A-2 of the first precast refractory block 10A, as shown in Figures 7A and 7B. The spacer 15 has an inverted L-shape, as shown in Figure 9. The upper horizontal portion, 15a, is attached to the top surface 10A-1 of the first precast refractory block 10A, so that the vertically extending main body 15b of the spacer 15 abuts the other side surface 10A-2 of the first precast refractory block 10A. In this embodiment, as shown in FIGS. 7A and 7B, two spacers 15 are attached to the other side surface 10A-2 of the first precast refractory block 10A.

[0019] Furthermore, before the step of installing the second precast refractory block 10B is performed, a step of drawing a furnace length direction scribing line 11 on the top surface 10B-1 of the second precast refractory block 10B and a step of drawing a furnace height direction scribing line 12 on the other side surface 10B-2 of the second precast refractory block 10B so that the scribing line 11 is continuous with the furnace length direction scribing line 11 is performed. The furnace length direction scribing line 11 and furnace height direction scribing line 12 on the second precast refractory block 10B are shown in Figure 7A, but the details of the scribing process and the preferred form are the same as those for the first precast refractory block 10A described above. Note that the steps of drawing the furnace length direction scribing line 11 and furnace height direction scribing line 12 on the second precast refractory block 10B and the step of attaching the spacer 15 described above may be performed either first or simultaneously.

[0020] The process of installing the second precast refractory block 10B is essentially the same as the process of installing the first precast refractory block 10A described above. The second precast refractory block 10B is installed while adjusting its position and orientation so that the laser beam 8 overlaps the furnace length direction scribing line 11 and furnace height direction scribing line 12 drawn on the top surface 10B-1 and the other side surface 10B-2 of the second precast refractory block 10B, which is lifted by a lifting device (not shown). In addition, when installing the second precast refractory block 10B adjacent to the other side surface 10A-2 of the first precast refractory block 10A, the position of the second precast refractory block 10B is adjusted so that the one side surface 10B-3, which is the side surface facing one side of the coke oven in the furnace length direction Y, contacts the main body 15b of the spacer 15. After installation of the second precast refractory block 10B is complete, the spacer 15 is removed. As a result, as shown in Figures 8A and 8B, the second precast refractory block 10B is installed adjacent to the other side surface 10A-2 of the first precast refractory block 10A, with a gap W equal to the thickness of the main body 15b of the spacer 15. Note that, as shown in Figures 7A and 7B, mortar 14 is applied in advance to the position where the second precast refractory block 10B will be installed. Then, mortar is applied to the above-mentioned gap W in a later process to form a mortar joint. Note that in Figures 7A and 7B, the hanging ring 13 removed from the first precast refractory block 10A is attached to the top surface 10B-1 of the second precast refractory block 10B.

[0021] Here, when installing the second precast fireproof block 10B, adjusting the position of the second precast fireproof block 10B so that one side surface 10B-3 of the second precast fireproof block 10B comes into contact with the spacer 15 (main body 15b) refers to a concept that includes not only ensuring that one side surface 10B-3 of the second precast fireproof block 10B comes into contact with the spacer 15 (main body 15b) while the second precast fireproof block 10B, which has been lifted by a lifting device, is being installed at a predetermined installation position adjacent to the first precast fireproof block 10A, but also temporarily placing the second precast fireproof block 10B, which has been lifted by a lifting device, in a position near the predetermined installation position adjacent to the first precast fireproof block 10A, and then moving the second precast fireproof block 10B horizontally so that one side surface 10B-3 comes into contact with the spacer 15 (main body 15b). In either case, by adjusting the position of the second precast fire-resistant block 10B so that one side surface 10B-3 of the second precast fire-resistant block 10B contacts the spacer 15 (main body portion 15b), the second precast fire-resistant block 10B is installed adjacent to the other side surface 10A-2 of the first precast fire-resistant block 10A through a gap W equal to the thickness of the main body portion 15b of the spacer 15.

[0022] After the installation of the second precast refractory block 10B is completed, a third precast refractory block is installed adjacent to the other side surface 10B-1 of the second precast refractory block 10B (not shown), and then a fourth precast refractory block is installed adjacent to the other side surface of the third precast refractory block, and so on, until multiple precast refractory blocks are installed adjacent to each other up to a position adjacent to the in-furnace side surface 6b-1 of the backstay 6b installed on the other side of the coke oven in the furnace length direction Y. In this case, the precast refractory blocks are installed adjacent to each other using the spacer 15 in the above-described manner, and by adjusting the position and attitude using the laser light 8, the furnace length direction scribing line 11, and the furnace height direction scribing line 12. In a coke oven, as shown in FIG. 2B, for example, multiple pairs of opposing backstays 6a, 6b are arranged in the oven width direction X, and multiple precast refractory blocks are installed adjacent to each pair of backstays 6a, 6b.

[0023] Next, a method for installing a precast refractory block on top of an already installed precast refractory block will be described. In this invention, the precast refractory block installed on top of the already installed precast refractory block is called the upper precast refractory block, and the already installed precast refractory block and the upper precast refractory block basically have the same shape. Hereinafter, a method for installing an upper precast refractory block will be described, taking as an example a case where an upper precast refractory block of the same shape is installed on the top surface of the second precast refractory block 10B.

[0024] 10A and 10B show the state before the upper precast refractory block is placed on top of the second precast refractory block 10B in the process of placing the upper precast refractory block on top of the first tier of precast refractory blocks including the second precast refractory block 10B. Note that in FIGS. 10A and 10B, only the top surface of the first tier of precast refractory blocks including the second precast refractory block 10B is conceptually shown, and the rest of the block is omitted. The same applies to FIGS. 11A and 11B, 12A and 12B, and 13A and 13B, which will be described later.

[0025] When placing an upper precast refractory block on the top surface 10B-1 of the second precast refractory block 10B shown in FIGS. 10A and 10B, a process of applying mortar 14 to the top surface 10B-1 of the second precast refractory block 10B and attaching spacers 15 is performed beforehand, as shown in FIGS. 11A and 11B. In the process of applying mortar 14, mortar 14 is applied to the entire top surface 10B-1 of the second precast refractory block 10B, except for the peripheral edge portion. The area of ​​the peripheral edge not covered with mortar 14 can be approximately 5 to 20% of the total area of ​​the top surface 10B-1. In other words, the area covered with mortar 14 can be approximately 80 to 95% of the total area of ​​the top surface 10B-1. On the other hand, in the step of attaching the spacers 15, the spacers 15 are attached to the side surfaces of the three upper precast refractory blocks surrounding the top surface 10B-1 of the second precast refractory block 10B in the same manner as described above.

[0026] After the steps of applying mortar 14 and attaching spacers 15 are completed, the upper precast refractory block 10C is placed on the second precast refractory block 10A, as shown in Figures 12A and 12B and 13A and 13B. However, before this step, a furnace length direction scribing line 11 is drawn on the top surface 10C-1 of the upper precast refractory block 10C, and a furnace height direction scribing line 12 is drawn on the other side surface 10C-2 of the upper precast refractory block 10C so that the scribing line 11 is continuous with the furnace length direction scribing line 11. The details of these scribing steps and the preferred embodiment are the same as those for the first precast refractory block 10A. Note that the steps of drawing the furnace length direction scribing line 11 and the furnace height direction scribing line 12 on the upper precast refractory block 10C may be performed before the steps of applying mortar 14 and attaching spacers 15, or may be performed simultaneously.

[0027] The process of installing the upper precast refractory block 10C is essentially the same as the process of installing the first and second precast refractory blocks 10A and 10B described above. The position and orientation of the upper precast refractory block 10C are adjusted so that the laser beam 8 overlaps the furnace length marking lines 11 and furnace height marking lines 12 drawn on the top surface 10C-1 and the other side surface 10C-2 of the upper precast refractory block 10C, which is lifted by a lifting device (not shown). Additionally, as with the installation of the second precast refractory block 10B described above, the position of the upper precast refractory block 10C is adjusted so that each of its three sides contacts the main body 15b of the spacer 15. After installation of the upper precast refractory block 10C is complete, the spacer 15 is removed. As a result, as shown in Figures 13A and 13B, the upper precast refractory block 10C is installed adjacent to the three surrounding upper precast refractory blocks, with a gap W equal to the thickness of the main body 15b of the spacer 15. In Figures 12A and 12B, a hanging ring 13 is attached to the top surface 10C-1 of the upper precast refractory block 10C. In addition, in Figures 12A and 12B, the spacer 15 shown in Figures 11A and 11B is omitted.

[0028] Other upper precast fireproof blocks other than upper precast fireproof block 10C are installed in the same manner as upper precast fireproof block 10C. At this time, spacers 15 are attached appropriately to the sides of the adjacent upper precast fireproof blocks that have already been installed. Then, once the installation of the second tier of precast fireproof blocks is complete, the third tier of precast fireproof blocks is installed in the same manner as the second tier. The same applies to the fourth tier and beyond.

[0029] In this embodiment, a refractory structure such as a regenerator chamber of a coke oven is constructed by sequentially installing precast refractory blocks between a pair of opposing backstays 6a, 6b as described above. At this time, the shape of the precast refractory blocks to be installed is appropriately changed depending on the refractory structure to be constructed.

[0030] As described above, according to this embodiment, when installing a precast refractory block, the laser beam 8 is directed so that it overlaps the vertical reference line 7 drawn on the furnace-inside side surface 6a-1 of the backstay 6a, and the precast refractory block is installed so that this laser beam 8 overlaps the furnace-length direction scribing line 11 and the furnace-height direction scribing line 12 drawn on the precast refractory block. This allows the precast refractory block lifted by the lifting tool to be accurately positioned and installed in the predetermined installation position. Furthermore, when installing another precast refractory block adjacent to an already installed precast refractory block, it is possible to prevent the other precast refractory block from coming into contact with the already installed precast refractory block, thereby preventing damage to the precast refractory block.

[0031] Furthermore, when installing another precast fire-resistant block adjacent to an already installed precast fire-resistant block, the position of the other precast fire-resistant block can be adjusted using the spacer 15 so that the side of the other precast fire-resistant block comes into contact with the spacer 15, thereby easily and accurately forming a gap W for forming a mortar joint between adjacent precast fire-resistant blocks.

[0032] Furthermore, when installing upper precast refractory blocks on top of existing precast refractory blocks, applying mortar 14 to the top surfaces of the installed precast refractory blocks, except for the peripheral edges of the top surfaces of the installed precast refractory blocks, can prevent the upper precast refractory blocks from being installed at an angle. In other words, if mortar 14 is applied to the entire top surfaces of the installed precast refractory blocks, when the upper precast refractory blocks are installed on top of them, the mortar 14 will flow out to the surrounding areas. If the flow direction is uneven, the thickness of the mortar remaining on the top surfaces of the precast refractory blocks will vary, resulting in the upper precast refractory blocks being installed at an angle. For example, when an upper precast refractory block is installed in a position surrounded by three upper precast refractory blocks as shown in Figures 10A and 10B, the flow direction of mortar 14 will mostly be toward the other side of the coke oven's furnace length direction Y. As a result, the thickness of the mortar remaining on the top surface of the precast refractory block becomes thinner as it moves toward the other side in the furnace length direction Y of the coke oven, and as a result, the upper precast refractory block is installed at an angle so that it becomes lower as it moves toward the other side in the furnace length direction Y of the coke oven. In contrast, in this embodiment, the mortar 14 is applied to the upper surface of the installed precast refractory block except for the peripheral edge, so the mortar 14 does not flow out or is less likely to flow out, reducing the deviation in the flow direction of the mortar 14. As a result, it is possible to prevent the upper precast refractory block from being installed at an angle. [Explanation of symbols]

[0033] A Coke oven X Furnace width direction Y Furnace length direction Z Furnace method W Gap 1 carbonization chamber 2. Combustion chamber 3 Furnace top 4 Heat storage chamber 5. Retaining walls 6a, 6b Backstay 6a-1, 6b-1 Furnace-inside side of backstay 7 Vertical Reference Line 8. Laser Light 9 Laser Oscillator 10A No. 1 Precast Fireproof Block 10A-1 Top surface 10A-2 Other side 10B No. 2 Precast Fireproof Block 10B-1 Top surface 10B-2 Other side side 10B-3 One side 10C Upper precast fireproof block 10C-1 Top surface 10C-2 Other side side 11 Furnace length direction marking line 12 Furnace height direction marking line 13 Hanging Ring 14 Mortar 15 spacer

Claims

1. a step of drawing a vertical reference line on a furnace-inside side surface of a backstay installed on one side in the furnace length direction of the coke oven; irradiating the coke oven with a laser beam from the other side in the furnace length direction so as to overlap the vertical reference line; a step of drawing a furnace length direction marking line on the top surface of a first precast refractory block installed adjacent to the furnace inside side surface of the backstay, and drawing a furnace height direction marking line on the other side surface that faces the other side of the coke oven in the furnace length direction when installing the first precast refractory block so that the marking line is continuous with the furnace length direction marking line; and installing the first precast refractory block so that the laser light overlaps the furnace length direction marking line and the furnace height direction marking line.

2. attaching a spacer to the other side surface of the first precast refractory block after installation; a step of drawing a furnace length direction marking line on the top surface of a second precast refractory block installed adjacent to the other side surface of the first precast refractory block, and drawing a furnace height direction marking line on the other side surface of the second precast refractory block so as to be continuous with the furnace length direction marking line; and installing the second precast refractory block so that the laser light overlaps the furnace length direction marking line and the furnace height direction marking line of the second precast refractory block, 2. The method for installing precast refractory blocks for a coke oven according to claim 1, wherein the step of installing the second precast refractory block includes a step of adjusting a position of the second precast refractory block so that one side surface of the second precast refractory block, which is a side surface opposite one side of the coke oven in the furnace longitudinal direction, contacts the spacer when installing the second precast refractory block.

3. applying mortar to the top surface of the installed precast refractory blocks; a step of drawing a furnace length direction marking line on the upper surface of an upper precast refractory block to be installed on the upper surface of the installed precast refractory block, and drawing a furnace height direction marking line on the other side surface of the upper precast refractory block so as to be continuous with the furnace length direction marking line; and installing the upper precast refractory block so that the laser light overlaps the furnace length direction marking line and the furnace height direction marking line of the upper precast refractory block, 3. The method for installing precast refractory blocks for a coke oven according to claim 1, wherein in the step of applying mortar, mortar is applied to the upper surface of the installed precast refractory block except for the peripheral edge portion.

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