How to repair a stave

Abstract

This invention provides a method for repairing staves that can reliably repair damaged sections in the cooling water pipes of staves installed in blast furnaces. [Solution] A method for repairing a stave 2 installed in a blast furnace and containing a cooling water pipe 21, wherein a damaged portion is formed in the cooling water pipe 21, and an expander 11 is installed in the region below the damaged portion inside the cooling water pipe 21 to block the inside of the cooling water pipe 21, and a repair member is filled in the region above the expander 11 inside the cooling water pipe 21 to fill the upper region, thereby forming a new cooling water channel 23c in the lower region.

Description

Technical Field

[0001] The present invention relates to a method for repairing a stave provided in a blast furnace and having a built-in cooling water pipe.

Background Art

[0002] In Patent Document 1, when a crack occurs in the cooling water pipe of a stave cooler, a liquid sealant that is soluble in the cooling water is injected into the cooling water pipe, penetrates into the crack, solidifies, and seals the crack to repair the leakage point. A method for repairing a furnace body cooling device for a blast furnace is disclosed. In the case of this repair method, if the crack is about 1 mm or less, the crack part can be sealed with the liquid sealant, so that the repair of the stave can be easily performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the case of the above conventional repair method, there is also a problem that the sealing performance is not sufficient only by solidifying the liquid sealant, and it is difficult to seal a larger crack.

[0005] The present invention has been made in view of such circumstances, and its main object is to provide a method for repairing a stave that can solve the above problems.

Means for Solving the Problems

[0006] To solve the above-mentioned problems, one aspect of the present invention provides a method for repairing a stave provided in a blast furnace and containing a cooling water pipe, wherein a damaged portion is formed in the cooling water pipe, and the cooling water pipe is sealed by installing a sealing member in a region below the damaged portion within the cooling water pipe, and the region above the sealing member within the cooling water pipe is filled with a repair member to fill the upper region, thereby forming a new cooling water channel in the lower region.

[0007] In this embodiment, the blocking member is composed of an expandable expander, and the cooling water pipe may be blocked by inserting the expander into the lower region and expanding the expander.

[0008] In the above embodiment, the inflatable body may be a rubber tube, and may be configured to be inflatable by supplying air inside it.

[0009] In the above embodiment, two openings may be formed in the cooling water pipe, separated vertically. The expansion body, to which the string-like member is attached, may be inserted into the cooling water pipe together with the string-like member through the upper opening, and the string-like member may be pulled out to the outside of the cooling water pipe through the lower opening, thereby positioning the expansion body inside the cooling water pipe.

[0010] In addition, in the above embodiment, the new cooling water channel may be formed through the lower opening. [Effects of the Invention]

[0011] According to the stave repair method of the present invention, it becomes possible to reliably seal off the damaged portion formed in the cooling water pipe of the stave. [Brief explanation of the drawing]

[0012] [Figure 1] A side view showing the configuration of the occluding device according to the embodiment. [Figure 2]Side cross-sectional view showing a schematic configuration of a stay to be repaired. [Figure 3] Flowchart showing steps of a method for repairing a stay according to an embodiment. [Figure 4] Side cross-sectional view showing a schematic configuration of a stay in an opening formation step. [Figure 5A] Side view showing a configuration of a guide jig used for opening formation. [Figure 5B] Front view showing a configuration of a guide jig used for opening formation. [Figure 6A] Side cross-sectional view showing a schematic configuration of a stay in an opening formation step. [Figure 6B] Side cross-sectional view showing a schematic configuration of a stay in an opening formation step. [Figure 7A] Enlarged side cross-sectional view showing a schematic configuration of a stay in a plug insertion step. [Figure 7B] Enlarged side cross-sectional view showing a schematic configuration of a stay in a plug insertion step. [Figure 8] Enlarged side cross-sectional view showing a schematic configuration of a stay in a cooling water pipe closing step. [Figure 9] Side cross-sectional view showing a schematic configuration of a stay in a copper powder filling step. [Figure 10] Side cross-sectional view showing a schematic configuration of a stay in a new flow path formation step.

Mode for Carrying Out the Invention

[0013] The method for repairing a stay according to the present embodiment forms a new cooling water flow path after filling a region including the damaged part with a repair member when damage occurs in a cooling water pipe. Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0014] (Configuration of Plug) In this embodiment, as will be described later, a plug for blocking the cooling water pipe of the stay is used. FIG. 1 is a side view showing the configuration of the plug. As shown in FIG. 1, the plug 1 includes a cylindrical inflatable body 11 and fittings 12 and 13 attached to both ends of the inflatable body 11.

[0015] The inflatable body 11 is composed of a rubber tube and can be inflated by sending air into it. After the plug 1 is inserted into the cooling water pipe, the cooling water pipe is blocked by inflating the inflatable body 11.

[0016] The fitting 12 is a cylindrical metal member and is connected to a tube used to send air into the inflatable body 11. The fitting 13 is a cylindrical metal member having a conical tip. A through-hole 14 penetrating in the left-right direction (the front-back direction in the drawing) is provided at the tip. As will be described later, a wire used when inserting the plug 1 into the cooling water pipe is attached to the through-hole 14.

[0017] (Configuration of the Stay) Next, the configuration of the stay to be repaired will be described. FIG. 2 is a side cross-sectional view showing the schematic configuration of the stay. In FIG. 2, reference numeral 2 indicates a copper stay, reference numeral 3 indicates a refractory, and reference numeral 4 indicates an iron skin. The stay 2 includes a copper cooling water pipe 21 through which cooling water flows. The cooling water pipe 21 is connected to a drain pipe 23a for discharging cooling water and a water supply pipe 23b for supplying cooling water. In the example shown in FIG. 2, the drain pipe 23a is disposed above the water supply pipe 23b.

[0018] When raw iron materials are supplied into the blast furnace, the materials come into contact with the staves 2 installed inside the furnace body, causing wear on the staves 2. When this wear progresses to the cooling water pipes 21, the cooling water pipes 21 become damaged, and water leakage occurs. Reference numeral 22 in Figure 2 indicates the damaged area. In this embodiment, the area including the damaged area 22 is repaired by filling it with a repair material.

[0019] (How to repair staves) Next, the method for repairing the stave using the above-described sealing device 1 will be described in detail, broken down into each step. Figure 3 is a flowchart of the steps in this repair method. The explanation will continue below following this flowchart.

[0020] [Opening formation process (S11)] An opening is formed in the cooling water pipe 21 in order to insert the blockage device 1 into the cooling water pipe 21 of the stave 2. Figure 4 is a side cross-sectional view showing the schematic configuration of the stave during this opening formation process.

[0021] In this embodiment, two openings are formed in the cooling water pipe 21, separated vertically. To achieve this, first, two openings are formed in the steel shell 4 and refractory material 3, separated vertically. More specifically, a cylindrical hole is drilled into the steel shell 4 and refractory material 3 using a core drill. This hole penetrates the steel shell 4 and refractory material 3 to reach the staves 2, and its diameter is, for example, about 130 mm. By performing the drilling operation described above twice, two openings 5a and 5b are formed in the steel shell 4 and refractory material 3, separated vertically, as shown in Figure 4.

[0022] Next, two openings are formed within the stave 2 that reach the cooling water pipe 21 via the openings 5a and 5b described above. In this case, an air ball is used. Here, the diameter of the cooling water pipe 21 is about 50 mm, and it is necessary to form openings with a smaller diameter (for example, about 25 mm), so a considerable degree of precision is required. Therefore, in this embodiment, a guide jig is used to guide the direction of the drill's movement.

[0023] Figure 5A is a side view showing the configuration of the guide jig described above, and Figure 5B is a front view of the guide jig viewed from the front end (right side in Figure 5A). As shown in Figures 5A and 5B, the guide jig 6 comprises a cylindrical first cylindrical portion 61 and a covered cylindrical second cylindrical portion 62, which is connected to the rear end of the first cylindrical portion 61 and has a larger diameter than the first cylindrical portion 61. An opening is formed in the center of the lid portion 62a of the second cylindrical portion 62, and the first cylindrical portion 61 and the second cylindrical portion 62 are in communication through this opening.

[0024] The inner diameter of the first cylindrical portion 61 is large enough to allow the insertion of a drill to be attached to the air ball. In this embodiment, as described above, an opening of about 25 mm in diameter is formed in the cooling water pipe 21. Therefore, the diameter of the drill is about 25 mm, and in order to allow the insertion of that drill, the inner diameter of the first cylindrical portion 61 is about 30 mm.

[0025] Furthermore, the outer diameter of the second cylindrical portion 62 is slightly smaller than the diameter of the openings 5a and 5b, for example, about 128 mm. This allows the gap between the outer surface of the second cylindrical portion 62 and the openings 5a and 5b to be minimized after inserting the second cylindrical portion 62 into the openings 5a and 5b. As a result, the radial movement of the guide jig 6 can be restricted.

[0026] Figures 6A and 6B are side cross-sectional views showing the schematic configuration of the stave during the opening formation process. As shown in Figure 6A, after the first cylindrical portion 61 of the guide jig 6 is inserted into one of the openings 5a, an air ball drill (not shown) is inserted into the second cylindrical portion 62, forming a cylindrical through-hole in the stave 2 that reaches the cooling water pipe 21. At this time, the drill is guided by the guide jig 6 and moves in a straight line toward the center of the cooling water pipe 21 in the width direction. As a result, a through-hole with a diameter smaller than the diameter of the cooling water pipe 21 is formed in the center of the cooling water pipe 21 in the width direction. A cylindrical through-hole is similarly drilled in the other opening 5b. Figure 6B shows the openings 5c and 5d formed in the stave 2 in this manner.

[0027] [Insertion of occlusion device (S12)] The blockage device 1 is inserted into the cooling water pipe 21 through the openings 5a to 5d formed in the stave 2 by the opening formation process described above. Figures 7A and 7B are enlarged side cross-sectional views showing the schematic configuration of the stave during this blockage device insertion process.

[0028] As shown in Figure 7A, a cylindrical guide pipe 7 is inserted into the opening 5c ​​through the opening 5a, and then the closure device 1 is inserted into the guide pipe 7. A rubber tube 81, used to supply air to the inflatable body 11, is attached to the fitting 12 at the rear end of the closure device 1.

[0029] Furthermore, a wire 82 is attached to the metal fitting 13 at the front end of the closure device 1. The tip 83 of this wire 82 is processed into a loop shape. After this tip 83 is inserted into the cooling water pipe 21, it is pulled out towards the opening 5b through the lower opening 5d. As a result, as shown in Figure 7A, the tip 83 of the wire 82 is positioned inside the opening 5b. If the tip 83 is pulled out further in this state, the closure device 1 falls out of the guide pipe 7 into the cooling water pipe 21. As a result, as shown in Figure 7B, the closure device 1 is positioned inside the cooling water pipe 21 with the cylindrical expansion body 11 extending in the vertical direction. This completes the closure device insertion process.

[0030] In the above description, the wire 82 is attached to the fitting 13 of the closure device 1 before its tip 83 is inserted into the cooling water pipe 21, but this is not the only way to proceed. For example, the wire 82 may be inserted into the cooling water pipe 21 first through the openings 5c and 5d, and then the wire 82 may be attached to the fitting 13 of the closure device 1.

[0031] [Cooling water pipe blocking process (S13)] The blocking device 1 inserted into the cooling water pipe 21 by the blocking device insertion process described above is used to block the cooling water pipe 21. Figure 8 is an enlarged side cross-sectional view showing the schematic configuration of the stave in this cooling water pipe blocking process. First, the rubber tube 81 is connected to an air pump (not shown) via the guide pipe 7. Then, air is supplied from the air pump to the expander 11 via the rubber tube 81. As a result, the expander 11 expands inside the cooling water pipe 21 and comes into contact with the inner surface of the cooling water pipe 21, thereby blocking the inside of the cooling water pipe 21.

[0032] After the cooling water pipe 21 is blocked by the blocking device 1 as described above, the guide pipe 7 is pulled out from the openings 5c and 5a and removed. Also, the wire 82 is pulled out by operating the tip 83 and separated from the fitting 13 of the blocking device 1 and removed. This completes the cooling water pipe blocking process.

[0033] [Copper powder filling process (S14)] After the cooling water pipe 21 is blocked by the cooling water pipe blocking process described above, copper powder (an example of a repair material) is filled into the area above the blocked portion of the cooling water pipe 21. Figure 9 is a side cross-sectional view showing the schematic configuration of the stave in this copper powder filling process.

[0034] First, copper powder is poured into the cooling water pipe 21 from the drain pipe 23a. After a predetermined time has elapsed, the copper powder inside the cooling water pipe 21 hardens. In this way, the area inside the cooling water pipe 21, including the damaged part, is filled with copper powder.

[0035] Next, the openings 5c and 5a are filled with a filling material and sealed with a sealing plate (not shown). This completes the copper powder filling process.

[0036] [New channel formation process (S15)] After the damaged portion inside the cooling water pipe 21 is repaired by the copper powder filling process described above, a new cooling water channel is formed inside the cooling water pipe 21. Figure 10 is a side cross-sectional view showing the schematic configuration of the stave in this new channel formation process.

[0037] First, a new cylindrical drain pipe 23c is inserted into the cooling water pipe 21 through the lower openings 5d and 5b. Next, the drain pipe 23c is fixed in place and the cooling water is prevented from leaking by embedding material into the openings 5d and 5b. This creates a new flow path through the drain pipe 23c.

[0038] As described above, in this embodiment, not only the damaged portion within the cooling water pipe 21 but also the area including the damaged portion is filled with copper powder, thus reliably preventing water leakage from the damaged portion.

[0039] Furthermore, since the blockage device 1 can be placed at any position within the cooling water pipe 21, flexible responses are possible depending on the location of the damage and the extent of the area to be filled with copper powder. [Explanation of Symbols]

[0040] 1 Obturator 11. Expanding body 12,13 Metal fittings 14 Through holes 2 stab 21 Cooling water pipe 23a, 23c Drain pipes 23b Water supply pipe 22 Damaged area 3 Refractories 4 Ironhide 5a~5d opening 6 Guide jig 61 First cylinder part 62 Second cylinder part 62a Lid 7 Guide pipe 81 Rubber tube 82 wires 83 Tip

Claims

1. A method for repairing a stave installed in a blast furnace and containing a cooling water pipe, The aforementioned cooling water pipe has a damaged portion, Two openings are formed in the cooling water pipe, separated in the vertical direction. An inflatable inflatable body to which a string-like member is attached is inserted into the cooling water pipe through the upper opening together with the string-like member. By pulling the string-like member outwards from the cooling water pipe through the lower opening, the expansion body is positioned in a region below the damaged area within the cooling water pipe. By expanding the aforementioned expandable body, the inside of the cooling water pipe is blocked, The repair member is filled into the area above the expansion body within the cooling water pipe to fill the upper area. A new cooling water channel is formed in the lower region. Repair method.

2. The inflatable body is a rubber tube, and is configured to be inflatable when air is supplied to its interior. A method for repairing a stave according to claim 1.

3. The new cooling water channel is formed through the lower opening. A method for repairing a stave according to claim 1 or 2.

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