WO2008056456A1 - Boiler water wall panel - Google Patents

Abstract

[PROBLEMS] To attain a reduction of weld working load at the fabrication of boiler water wall panel and attain a reduction of maintenance load and enhancement of rate of operation for a furnace housing with built-in boiler water wall panel. [MEANS FOR SOLVING PROBLEMS] Boiler water wall panel (80) comprises panel body (70) with water channel having constituent units of metallic seamless finned single tubes (60) integrally fabricated by hot extrusion technique, etc., these metallic seamless finned single tubes at the distal end of fin portion (62) welded and connected to each other as seam (71) and, provided on at least one surface side of the panel body (70), internal central region weld coating (82) and periphery weld coating (81) of anticorrosion alloy. The finned tube body (60) has tube body part (61) for cooling water channel and, extending on both sides thereof in the direction of tube body axial line, a pair of fin portions (62) wherein intervening portion (63) has an external surface formed into a concave curved surface of 3 to 6 mm curvature radius.

Description

 Specification

 Boiler water wall panel

 Technical field

 TECHNICAL FIELD [0001] The present invention relates to a boiler water wall panel constituting a furnace housing with a cooling water channel.

 The boiler water wall panel is a composite panel of plate and tube, and is used as an element material when forming the wall panel of the furnace (combustion chamber / heat exchanger) housing, which is the heart of the hydrothermal boiler. A large number of sheets are welded and connected vertically and horizontally to form a furnace housing.

 The boiler water wall panel is coated with an alloy such as a nickel self-fluxing alloy on one side in order to improve the durability of the inner surface of the furnace housing.

 Background art

 [0002] A method of heating water-cooled panel segments having alternately arranged metal tube portions and metal plate portions so as not to cause thermal strain is known (see, for example, Patent Document 1). The structure and manufacturing method of this water-cooled panel segment 20 (boiler water wall panel) will be described with reference to the drawings. 3A is a side view of the metal tube portion 21 and the metal plate portion 22, FIG. 3B is a cross-sectional view thereof, and FIG. 3C is a cross-sectional view of the water-cooled panel segment 20. In this specification, the transverse section refers to a section perpendicular to the tube axis direction.

[0003] The number of metal tube portions 21 and metal plate portions 22 that are necessary to form a panel by alternately arranging them separately is made individually, and the lengths are aligned at that time (Fig. 3 (a), ( b)). Then (see Fig. 3 (c)), the first metal plate portion 22 is attached to the side of the first metal tube portion 21 so as to extend in the axial direction of the tube body. The peripheral surface of the pipe part 21 is welded in a linear form, and the next metal plate part 22 is attached to the other side of the first metal pipe part 21 in a state that also extends in the axial direction of the pipe. One long side of the plate portion 22 and the peripheral surface of the metal tube portion 21 are welded in a line, and the next metal tube portion 21 is attached to the metal plate portion 22 so that the plate body long side direction and the tube axis direction are connected. The other long side of the metal plate part 22 and the peripheral surface of the metal pipe part 21 are welded in a line in a state of alignment, and the same welded connection is repeated to provide a water channel that is the base material of the water-cooled panel segment 20 A panel body is created. [0004] Furthermore, for each such panel body with a water channel, a self-fluxing alloy coating made of a self-fluxing alloy material such as a Ni—Cr group is formed on one side or both sides of the water-cooled panel segment. Is completed. The coating is formed by a thermal spraying fusing method. Specifically, the outer surface of the water-cooled panel segment 20 is formed by forming a layer of a coating material by a thermal spraying method and then performing a fusing treatment on the outer layer. .

 Due to such a manufacturing method, in this water-cooled panel segment 20, the base material has a welded structure in which the switching portion 23 from the metal pipe portion 21 to the metal plate portion 22 is formed by welding.

[0005] As another manufacturing method and structure, a water-cooled panel is formed by forming a self-fluxing alloy protective coating on the outer surface of a finned tube body in which metal plate vertical fins are erected on both sides of the metal tube. A panel manufacturing method is known in which a unit member for a segment is used, and a plurality of the unit members are made into water-cooled panel segments by mutual welding connection at the ends of vertical fins (see, for example, Patent Document 2). The structure and manufacturing method of this water-cooled panel segment 50 (boiler water wall panel) will be described with reference to the drawings. 4 (a) is a side view of the metal tube 31 and the vertical fin 32, (b) is a cross-sectional view thereof, (c) is a cross-sectional view of the finned tube 30, and (d) is for a water-cooled panel segment. A side view of the unit member 40, (e) is a cross-sectional view thereof, and (f) is a cross-sectional view of the water-cooled panel segment 50.

 [0006] In this case as well, the metal pipe 31 that serves as the cooling water channel and the vertical fin 32 that serves as the web are a pair of one and two, but they are made separately (Fig. 4 (a), (Refer to (b)), and the lengths for the number of sets required for the water-cooled panel segment 50 are aligned. And (see Fig. 4 (c)), for each set, a pair of vertical fins 32 are attached to both sides of the metal tube 31 in a state of extending in the axial direction of the tube, and one long side of the vertical fin 32 and the metal The peripheral surface of the pipe 31 is linearly welded to form a finned pipe body 30 having a metal pipe 31 and a pair of vertical fins 32 provided on both sides thereof and extending in the pipe body axial direction. Therefore, even such a finned tube 30 has a welded structure in which the switching portion 33 from the metal tube 31 to the vertical fin 32 is formed by welding.

[0007] Then (see FIGS. 4 (d) and (e)), each of the finned tubes 30 is coated with a self-fluxing alloy-based material with a self-fluxing alloy-based material such as Ni_Cr on each side. 41 is formed, and a water-cooled panel segment unit member 40 is formed. The coating is also a force formed by thermal spraying-fusing treatment method. This is performed individually for the water-cooled panel segment unit member 40 before assembly, not for the segment 50. Thereafter (see FIG. 4 (f)), the water cooling panel segment unit member 40 is used as a structural unit, and a plurality of the units are welded and connected to each other with the end of the vertical fin 32 as a joint 51. Segment 50 is completed.

 [0008] In addition, although not shown in the figure, when the panel base material before forming the coating of the water-cooled panel segment 20 is used as the panel base material, and a weld coating with a corrosion-resistant alloy is formed on one side of the panel base material, Technology to make boiler furnace panels by applying superalloy coating by welding overlaying to the end portion to be welded, and self-fluxing alloy coating by spraying and fusing treatment on the inner side. (For example, refer to Patent Document 3), while heating in the fusing process after thermal spraying, pulling the boiler panel in the longitudinal direction with the towing tool while crossing the longitudinal direction with the position forcing tool at many locations in the biaxial direction Also known is a method of manufacturing an alloy-coated boiler panel in which deformation is corrected by regulating in (see, for example, Patent Document 4). These boiler water wall panels also have a welded structure in which the switching portion 23 from the metal pipe portion 21 to the metal plate portion 22 is formed by welding.

 Patent Document 1: Japanese Patent Application Laid-Open No. 2000-329304

 Patent Document 2: Japanese Patent Laid-Open No. 2001-004101

 Patent Document 3: Japanese Patent Laid-Open No. 2005-274022

 Patent Document 4: JP-A-2005-337623

 Disclosure of the invention

 Problems to be solved by the invention

[0010] However, in such a conventional boiler water wall panel, since the switching portion from the tube portion to the plate-like fin portion is welded and connected, the welding cannot be performed. It greatly affects the quality of boiler water wall panels. That is, when the boiler is used, the tube and fins are exposed to a high temperature environment. Since the tube is cooled from the hollow by water or steam, the fin is not cooled. That is, a thermal strain driving force is generated, and this switching part is the part where the stress is generated most. Therefore, if the switching part is not perfectly welded, for example, a pinhole, unevenness, blow hole, Overlap, undercut, slag entrainment, weld crack, spatter, weld bee If any one of the welding shapes is extremely uneven, they will become notches, and the corrosion coating of the corrosion-resistant alloy will be damaged from that point, which will cause corrosion on the base metal. It happens early.

 [0011] Defects in the weld are difficult to identify with the naked eye, so they must be confirmed by a dye penetration test, etc. Repair of welds where defects are found is performed after blasting and TIG welding. It is troublesome.

 In addition, welding between the tube and plate-like fins is more difficult than butt welding between the fin tips, so welding defects are more likely to occur in spite of man-hours. Subsequent inspections and repairs were heavy.

 Therefore, the construction of the boiler water wall panel should be improved in order to reduce the burden of welding work during the manufacture of boiler water wall panels and to reduce the maintenance load of the furnace housing with built-in boiler water wall panels and thus to improve the operating rate. Is a technical challenge.

 Means for solving the problem

[0012] The boiler water wall panel of the present invention (claim 1) was devised to solve such a problem, and a plurality of rows of tubes serving as cooling water channels and a web connecting the rows. And an outermost row tube body with a water channel panel provided with a pair of fins positioned on the outer side of the tube body and extending in the tube axis direction, and at least one surface of the base material is welded with a corrosion-resistant alloy. The boiler water wall panel, which is a base material, is made of a metal having a pair of fins that are continuous with the pipe body on both sides of a single pipe body. A single unit pipe with a seamless fin is used as a structural unit, and a plurality of the units are welded to each other at the tips of the fins of the structural unit, and a welded structure is formed in which a weld is located at the center line position of the web. It is characterized by that.

[0013] In addition, the boiler water wall panel of the present invention (Claim 2) is a tube located on the outer side of the outermost row tube body and a plurality of rows of tube bodies serving as cooling water channels, a web connecting the rows. A boiler water wall panel in which a metal channel panel body having a pair of fins extending in the body axis direction is used as a base material, and at least one surface of the base material is welded with a corrosion-resistant alloy. In the panel body with a water channel, which is a material, a few rows of tubes corresponding to a part of the plurality of rows, a web connecting between the rows, and a pair of fins located on the outer side of the outermost row of tubes are respectively continuous phases. After Metal seamless finned tube connected in series A web assembly is a structural unit, and a plurality of the members are welded to each other at the tips of the fins of the structural unit, and the position of the center line of some of the webs It is characterized by a welded structure in which the weld is located.

 [0014] Further, the boiler water wall panel of the present invention (Claim 3) includes a plurality of rows of pipes serving as cooling water channels, a web connecting between the rows, and an outermost row of pipes. A boiler water wall panel in which a metal channel panel body having a pair of fins extending in the body axis direction is used as a base material, and at least one surface of the base material is coated with a corrosion-resistant alloy. The panel body with a water channel, which is a base material, is made of a metal in which the plurality of rows of tubes, a web connecting the rows, and a pair of fins positioned on the outer side of the outermost row of tubes are connected with a continuous phase. Seamless finned tube—A feature of a seamless integrated structure in which the entire area of the panel body is formed only by integrating the web assembly.

 [0015] Further, a boiler water wall panel according to the present invention (Claim 4) is the boiler water wall panel according to Claims 1 to 3, and is further provided with the water channel panel body as a base material. The outer surface of the switching part from the tube body to the fin or the web is formed in a concave curved surface.

 [0016] In addition, a boiler water wall panel according to the present invention (Claim 5) is the boiler water wall panel according to Claims 1 to 4, further comprising the continuous material constituting the base material. A seamless finned single pipe or a finned pipe-one web assembly that is continuous with a phase is manufactured by a seamless molding method such as a hot extrusion method.

 [0017] Further, the boiler water wall panel according to the present invention (Claim 6) is the boiler water wall panel according to Claims 1 to 5, and further, the corrosion-resistant alloy constituting the weld coating is The frame-like region at the peripheral edge of the panel is characterized in that the Ni-rich Ni_Cr alloy is used as a base material and the B and Si contents are suppressed to 0.1 and 0.5 mass%, respectively.

 The invention's effect

[0018] In such a boiler water wall panel of the present invention (Claim 1), it is possible to manufacture by a hot extrusion method or the like, and a tubular body portion and a tubular body axial direction provided on both sides thereof. And a pair of fin portions extending in a seamless metal fin that are connected together in a continuous phase. Since the attached single pipe is used as a structural unit, it is not necessary to connect the switching part from the tube part to the fin part by welding. In addition, welding of the tip ends of the fin parts can be performed more easily than the welding of the above-mentioned switching parts, and the soundness of the welded part is high. This reduces the burden of welding work during the manufacture of boiler water wall panels, and for furnace housings that incorporate the finished boiler water wall panels, there are no welds at the above switching sites. Influence of notch due to welding variation of parts, etc. In addition to releasing the weld coating, the weld in the center of the web that replaces this weld is formed with high soundness. The necessity is remarkably reduced, the operating state is stabilized, and the operating rate is improved.

 [0019] Further, in the boiler water wall panel according to the present invention (Claim 2), there is no seam equivalent to connecting a few single pipes with the above-mentioned seamless fins integrally in the whole continuous phase. By adopting the finned tube assembly as a structural unit, it is not necessary to connect the switching part from the tube part to the fin part by welding, and the welding between the fin ends is also reduced. Become. This further reduces the burden of welding work when manufacturing boiler water wall panels, and further reduces the damage to the furnace housing that incorporates the boiler water wall panels.

 Therefore, according to the present invention (Claims 1 and 2), the burden of welding work during manufacturing of the boiler water wall panel is reduced, and the operating rate of the furnace housing incorporating the boiler water wall panel is improved. be able to.

[0020] Further, in the boiler water wall panel according to the present invention (Claim 3), the seamless fin is equivalent to a case where a plurality of the above-described single pipes with seamless fins are integrally connected in the whole continuous phase. Since the entire area of the panel body is configured only with the tube-to-tube assembly, it is not necessary to weld the tube part force switching part to the fin part, and there is no welding at the tip of the fin part. become. This will eliminate the process of welding the boiler water wall panel manufacturing process, and will further reduce the coating damage for the furnace housing incorporating the boiler water wall panel.

Therefore, according to the present invention (Claim 3), the burden of welding work in manufacturing the boiler water wall panel is eliminated, and a furnace housing incorporating the boiler water wall panel is provided. The operating rate of ging can be improved.

 In the boiler water wall panel according to the present invention (Claim 4), the outer surface of the switching portion from the tube portion to the fin or web portion in the panel body is formed in a concave curved surface shape. Therefore, the stress concentration on the part is relaxed and the cross-sectional shape of this part becomes a shape in which the thickness increases smoothly toward the root, thereby increasing the rigidity of this part and reducing the deformation caused by the stress. Therefore, the undesired influence of the stress due to the above-mentioned steep temperature gradient is reduced, and the above-mentioned preferable effects are increased. In addition, the concave curved surface can be easily formed by a seamless molding method such as a hot extrusion method, and contributes to a longer life of a mold member used in the hot extrusion method.

 [0022] Here, it is desirable that the radius of curvature of the concave curved surface formed on the outer surface of the switching portion from the tube portion to the fin portion is 3 mm or more. As a result, in a panel where the thickness of the tube portion and the web portion is usually several millimeters, in most cases, the stress concentration can be sufficiently relaxed and the rigidity can be remarkably increased. In addition, the notch effect on the coating is sufficiently mitigated by a radius of 3 mm or more. These effects become more prominent as the radius increases, but the radius should be limited to about 6 mm from the viewpoint of saturation of effects or avoidance of waste.

 [0023] Further, in the boiler water wall panel according to the present invention (Claim 5), the seamless single finned pipe or the finned pipe web assembly that is continuous with the continuous phase constituting the panel base material is provided. Since it is manufactured by a seamless molding method such as a hot extrusion method, it is reliably integrated with a continuous phase and is efficiently produced.

 In general, it is generally considered that the hot extrusion method is optimal for the production of seamless finned single pipes and seamless finned pipes and web assemblies. It is also possible to manufacture seamless structural units that make up the panel base material by seamless molding methods such as powder sintering, sand mold-making, and centrifuge fabrication.

[0024] Further, in the boiler water wall panel of the present invention (Claim 6), since the weld coating on the peripheral portion used for welding connection keeps the blending amount of B and Si to a minimum, The thermal shock cracking susceptibility of self-fluxing alloy materials containing B and Si is extremely low, so a furnace housing is constructed by welding and connecting boiler water wall panels. Well panel The fear of thermal shock cracking at the joints is largely eliminated. In addition, as a corrosion-resistant alloy having low thermal shock cracking sensitivity, the alloy according to claim 6 is superior in cost performance or availability, but other alloys (for example, JIS 4901 and 4902 or ISO 4955 are available depending on various requirements). , 9723 other alloys) may be applied.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0025] A configuration of a boiler water wall panel according to the present invention and a method for manufacturing the same will be described with reference to the drawings. 1 (a) is a side view of a finned tube 60, (b) is a cross-sectional view thereof, (c) is a side view of a panel base material 70, (d) is a cross-sectional view thereof, (e) Is a side view of boiler water wall panel 80, and (f) is a cross-sectional view thereof. In addition, the cross section in each cross section indicates a cross section orthogonal to the axial direction of the tube portion 61.

 [0026] In this boiler water wall panel 80, first, a finned tube body 60, which is a single tube with a seamless fin made of metal, which is the smallest structural unit, is integrally manufactured by a hot extrusion method ( Fig. L (a) and (b)), and by aligning the lengths of the plurality of such tubular bodies 60 with fins, and connecting the ends of the fin portions 62 with the seams 71 to each other by welding, It is manufactured by making a panel base material 70 that is the body (see Fig. 1 (c) and (d)), and then forming a weld coating with a corrosion-resistant alloy with one side of the panel base material 70 as the construction target surface. . For example, the weld coating of the corrosion-resistant alloy on the boiler water wall panel 80 (see Fig. 1 (e), (f)) is first applied to the frame-like region (81) at the peripheral edge of the surface to be constructed by welding overlaying. An alloy with no impact cracking susceptibility is applied, and an alloy with good workability by the spray-fusing treatment method, such as Ni-based (Ni_Cr base) or Co, is applied to the inner area (82) surrounded by the frame area. The self-fluxing alloy of the system (Co_Cr base, etc.), and these self-fluxing alloys with WC blended are applied.

[0027] The finned tube 60 (see Figs. L (a) and (b)) includes a tube portion 61 serving as a cooling water channel and a pair of fin portions 62 provided on both sides thereof and extending in the tube axis direction. The switching part 63 from the pipe body part 61 to the fin part 62 is integrated with the hot extrusion method instead of the welding connection. Further, the outer surface of the switching portion 63 is formed in a concave curved surface shape having a curvature radius of a minimum curvature radius portion of 3 mm or more and 6 mm or less. The tube 60 with fins is made of inexpensive rolled steel such as carbon steel or low alloy steel (Cr Mo steel, etc.). Are often used, but stainless steel, forged materials, and other metals may be used. In the case of a general boiler furnace panel, the dimensions are, for example, that the diameter of the tube portion 61 is about 60 to 80 mm, the thickness of the tube portion 61 is about 5 to 7 mm, and the width of the fin portion 62 is The thickness of the fin portion 62 is about 5 to 7 mm. The hot extrusion method may be the force S, in which the Ugine-Sejournet method using glass as a lubricant is widespread, and other methods.

[0028] The panel base material 70 (see FIGS. 1 (c) and 1 (d)) is made by welding from a plurality of the finned tube bodies 60 described above. Specifically, for example, about 5 to 20 finned tubular bodies 60, the lengths are aligned and arranged in parallel, and the tips of adjacent fin portions 62 are welded together to assemble them into a flat plate shape. It is a thing. In the case of a general boiler furnace panel, the general size of the panel base material 70 is a length force of about S4000 to 8000 mm and a width of about 400 to 1200 mm. The weld connection of the seam 71 in the panel base material 70 is performed by a general carbon gas arc welding method, TIG welding method, or the like, but it is sufficient to make the groove between the plate material and the plate material. Therefore, it is easy to work and the efficiency is improved, but almost no welding defect occurs. In the panel base material 70 of the welded structure thus formed, the butt welded fin portions 62 and 62 become webs that connect the tube body portions 61 and 61, and a seam 71 that is a welded portion is provided at the center line position of the web. positioned.

 [0029] The boiler water wall panel 80 (see FIGS. 1 (e) and 1 (f)) is completed by forming a peripheral edge weld coating 81 and an inner region weld coating 82 on the panel base material 70 described above.

 The corrosion resistant alloy that is not susceptible to thermal shock cracking and is used for the peripheral edge weld coating 81 is based on a Ni-rich Ni-Cr alloy, and the content of boron B, a melting point lowering element, is controlled to less than 0.1 lmass%. Another example is an alloy in which the content of silicon Si, which is also a melting point lowering element, is suppressed to 0.5 mass% or less. Standards governing such alloy materials include JISG4901 for bar materials and JISG4902 for plate materials in Japan, and IS 04955 and IS09723 strength S in international standards. The thickness of the peripheral edge weld coating 81 is about:! To 3 mm.

[0030] Since the peripheral portion of the panel base material 70 becomes a boiler water wall panel 80 and is used for welding connection with other panels, it is important that there is no thermal shock cracking susceptibility. Inner Since the area has been welded, the ease and cost of covering construction are important.

 As a corrosion-resistant alloy used for the inner region weld coating 82, Ni—Cr-based self-fluxing alloy can be cited as it is suitable for use in the thermal spraying fusing process and has good workability. The material is made of Ni-rich Ni_Cr component that occupies a majority amount S, easy meltability preferable for thermal spraying treatment and fusing treatment, self-fluxing action, etc., so that brittleness does not become excessive. The contents of B and Si are l-5 mass%, respectively. Examples of such alloy materials include nickel self-fluxing alloy materials having compositions defined in Japanese Standard JISH8303 and International Standard ISO14920. The thickness of the inner region welded coating 82 is normally about 0.5 to 3.0 mm. However, in the configuration of the present invention, the thickness of the tube-fin 'web switching portion and the welded portion are the same. Since the surface shape of the material is in order, sufficient protection is achieved if there is a covering with a thickness of 0.2 mm or more.

[0031] In forming the inner region welding coating 82, in the fusing process after the inner region welding coating 82 is sprayed on one side of the panel base material 70, a heating agent for local calorific heat in the panel longitudinal direction is formed. For example, while heating in the form of moving the induction coil, while the panel base material 70 is pulled in the longitudinal direction with the traction tool while heating, many displacements in the biaxial direction intersecting the longitudinal direction with the position forcing tool It is even better to correct the deformation by restricting with.

 The boiler water wall panel 80 produced in this way is transported from the panel manufacturing plant to the boiler installation site, and is connected to the other panel by welding at the periphery to be installed in the furnace housing.

 The configuration of the boiler water wall panel according to the present invention and the method for manufacturing the same will be described with reference to the drawings. Fig. 2 shows (a) a side view of a seamless finned tube-one web assembly 90, (b) a cross-sectional view thereof, and (c) a side view of a panel base material 95 (panel body with water channel). (D) is a cross-sectional view thereof. Here too, the cross section in each cross section indicates a cross section orthogonal to the axial direction of the tube portion 91.

 [0033] This boiler water wall panel is different from the above-described boiler water wall panel 80 in that the structural unit of the panel base material 95, which is a panel body with a water channel serving as a base material, is a seamless finned tube-web assembly. That is 90.

Seamless finned tube—web assembly 90 consists of only a few rows of tubes 91 and the space between them. A web portion 92 to be connected and a pair of fin portions 93 located on the outer side of the outermost tube body are provided, and they are connected in a continuous phase. It is integrally formed by the same hot extrusion method as the finned tube 60, but it is not a single tube like the finned tube 60, but the finned tube 60 is arranged side by side as if a part of the panel is assembled beforehand. A small number of tube sections 91 are included in parallel in the plane.

[0034] In part, the pipe portion 91 that serves as a cooling water channel is the same as the pipe portion 61, and the fin portion 93 may be the same as the fin portion 62, and the web portion 92 is equivalent to two fin portions 93. The switching portion 94 from the tubular portion 91 to the web portion 92 or the fin portion 93 may be the same as the switching portion 63.

 Seamless finned tube—a few rows of tube parts 91 included in the web assembly 90 correspond to a part of the plurality of rows of tube parts 91 included in the panel base material 95 and the boiler water wall panel. In the above example, three rows are shown, but there may be two rows, four rows, or more.

 Similar to the panel base material 70, such a panel base material 95 is also formed by welding connection from a plurality of seamless finned tube-web assembly 90. Specifically, the tips of adjacent fin portions 93 are assembled in a flat plate shape by welding and the fin portions 93 and 93 become webs by the welding connection are welds. Seam 96 will be located at the center line of the web. However, since the seam 96 does not exist in the web part 92 integrally formed with the pipe part 91 in the manufacturing stage of the seamless finned pipe-web assembly 90, the panel base material 95 is composed of a plurality of rows serving as cooling channels. This is a welded structure in which a weld is located at the center line position of a part of the webs connecting the rows of the tubular body portions 91. A pair of fin portions 93 are located further outside the outermost tube.

 [0036] Also on the panel base material 95 of the welded structure thus made, the same peripheral edge welding coating 81 and inner region welding coating 82 as the above-mentioned panel base material 70 are applied * formed and used for boiler water walls. The number of joints 96 in the panel base material 95 is smaller than the number of joints 71 in the panel base material 70.

The finished boiler water wall panel is still from the panel manufacturing plant to the boiler installation site. And is welded to the other panel and the peripheral edge, and incorporated into the furnace housing

[0037] Further embodiments of the configuration of the boiler water wall panel of the present invention and the manufacturing method thereof will be described.

 This embodiment can be said to be a modification of the above-described next embodiment. If FIG. 2 showing the structure of the panel base material according to the above-described next embodiment is diverted and described, Even the seam 96 in wood 95 is in an excluded form.

 That is, the seamless finned tube, which is the panel constituent unit of the next embodiment, the number of rows of the tube portions 91 in the web assembly 90 is increased to the number of rows of the tube portions 91 in the panel base material 95. Therefore, the seamless finned tube-one web assembly 90 is not a panel unit but a component for the entire panel.

 This further embodiment is first useful in cases where the panel matrix is relatively narrow (e.g., 400-600 mm Z tube section 3-6 mm 1 "). And according to the improvement of assembly manufacturing skills such as the hot extrusion method, the suitable target range will be expanded to a wider panel.

 [0039] [Others]

 In the above embodiment, the seamless finned single pipe 60 and the seamless finned pipe-web assembly 90 are produced by the hot extrusion method S, which is a seamless molding method instead of the hot extrusion method. Examples of techniques that can be used to manufacture a tubular body and fins and webs extending in the axial direction of the tubular body as an integrated body connected in a continuous phase include a powder sintering method, a sand mold-based forging method, and a centrifugal forging method.

 In the above embodiment, the thermal shock cracking susceptibility is low, the peripheral edge welding coating 81 made of an alloy is formed by the welding S method, and the coating S is formed by another method such as a thermal spraying and fusing method. If possible, the peripheral edge weld coating 81 may be formed therewith. Industrial applicability

[0040] The boiler water wall panel of the present invention can be applied to furnace housings of various boilers including so-called super boilers. An example of boiler installation is an incinerator. The incinerator for waste incineration power generation equipment is similar. Brief Description of Drawings

 [0041] FIG. 1 shows a structure of a boiler water wall panel and a method for manufacturing the same according to an embodiment of the present invention, in which (a) is a side view of a finned tube (seamless finned single tube); (b) is the cross-sectional view, (c) is the side view of the panel base material (panel body with water channel), (d) is the cross-sectional view, (e) is the side view of the boiler water wall panel, (f) Is a cross-sectional view thereof.

 FIG. 2 shows a structure of a boiler water wall panel and a method for manufacturing the same for another embodiment of the present invention, in which (a) is a side view of a seamless finned tube-web assembly, and (b) is a cross section thereof. (C) is a side view of a panel base material (panel body with water channel), and (d) is a cross-sectional view thereof.

 [Fig. 3] For an example of a conventional water-cooled panel segment, (a) is a side view of the metal tube and metal plate, (b) is a cross-sectional view thereof, and (c) is a cross-sectional view of the water-cooled panel segment. is there.

[Fig. 4] Regarding other examples of conventional water-cooled panel segments, (a) is a side view of a metal tube and vertical fins, (b) is a cross-sectional view thereof, (c) is a cross-sectional view of a tubular body with fins, (D) is a side view of a unit member for water-cooled panel segment, ( _e ) is a cross-sectional view thereof, and (f) is a cross-sectional view of a water-cooled panel segment.

 Explanation of symbols

 [0042] 20 · Water-cooled panel segment (boiler water wall panel),

 21 · Metal pipe part, 22 · Metal plate part, 23 · Switching part (welding),

 30 · Fined tube, 31 · Metal tube,

 32 · Vertical fins, 33 · Switching parts (welding),

 40 · Unit members for water-cooled panel segments, 41 · Self-fluxing alloy coating,

 50 · Water cooling panel segment (panel for boiler water wall), 51 · Joint (welding),

 60. Tube with fins (single tube with seamless fins),

 61 · Tube part, 62 · Fin part, 63 · Switching part (integral molding),

 70 · Panel base material (Panel body with water channel), 71 · Seam (weld in the center of the web),

 80 · Boiler water wall panel, 81 · Peripheral weld coating, 82 · Center region weld coating,

 90 · Seamless finned tube web assembly,

 91 tube part 92 web part 93 fin part 94 switching part

 95 · Panel base material (panel body with water channel), 96 · Seam (welded part in the center of the web)

Claims

The scope of the claims  [1] With a metal water passage provided with a plurality of rows of pipes serving as cooling water passages, a web connecting the rows, and a pair of fins positioned further outside the outermost row pipe and extending in the axial direction of the pipe A boiler water wall panel in which a panel body is used as a base material and at least one surface of the base material is coated with a corrosion-resistant alloy.  The water channel panel body, which is a base material, is composed of a plurality of metal single pipes with seamless fins having a pair of fins continuous with the pipe body on both sides of a single pipe body. Boiler water wall characterized in that the body is welded and connected to each other at the tips of the fins of the structural unit, and the welded portion is located at the center line position of the web. panel.  [2] With a metal water passage provided with a plurality of rows of pipes serving as cooling water channels, a web connecting the rows, and a pair of fins positioned on the outer side of the outermost row pipes and extending in the tube axis direction A boiler water wall panel in which a panel body is used as a base material and at least one surface of the base material is coated with a corrosion-resistant alloy.  The panel body with a water channel as a base material has a few rows of tubes corresponding to a part of the plurality of rows, a web connecting between the rows, and a pair of fins located further outside the outermost row tubes. Metal seamless finned pipes connected by a continuous phase--a tube assembly is used as a structural unit, and a plurality of them are welded to each other at the tips of the fins of the structural unit. A boiler water wall panel characterized by having a welded structure in which a weld is located at the center line position of some webs. [3] With a metal water passage provided with a plurality of rows of pipes serving as cooling water channels, a web connecting the rows, and a pair of fins positioned further outside the outermost row pipe and extending in the axial direction of the pipe A boiler water wall panel in which a panel body is used as a base material and at least one surface of the base material is coated with a corrosion-resistant alloy. The panel body with a water channel as a base material is a metal joint in which the plurality of rows of pipes, a web connecting the rows, and a pair of fins positioned on the outer side of the outermost row of pipes are connected in continuous phases. Nil finned tube Boiler water wall panel characterized by a seamless monolithic structure in which the entire area of the panel body is formed only by integrating the web assembly. [4] The boiler water wall panel according to any one of claims 1 to 3, wherein the pipe body in the water channel panel body, which is a base material, is cut into the fins and the web. A panel for boiler water walls, characterized in that the outer surface of the replacement part is formed in a concave curved surface.  [5] The boiler water wall panel according to any one of claims 1 to 4, wherein the seamless single-tube with fins or fins connected with the continuous phase constituting the base material is provided. Boiler-web assembly is a boiler water wall panel, which is manufactured by a seamless molding method such as a hot extrusion method.  [6] The boiler water wall panel according to any one of claims 1 to 5, wherein the corrosion-resistant alloy constituting the weld coating is a frame-shaped region at a peripheral portion of the panel. A boiler water wall panel characterized in that it is an alloy that uses a Ni-rich Ni_Cr alloy as a base material and has B and Si contents suppressed to 0.1 and 0.5 mass%, respectively.