JP2008116150A - Panel for boiler waterwall - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a burden of welding work in manufacturing a panel for a boiler waterwall and to reduce a maintenance burden of a furnace housing built in the panel for the boiler waterwall for improving an operating rate. <P>SOLUTION: In the panel 80 for the boiler waterwall, a panel body 70 with a water passage is constructed by alternately welding and connecting a plurality of metal single seamless finned tubes 60, each of which is integrally manufactured by a hot extrusion method and the like and serves as a component unit, together by using the tips of fin parts 62 as joints 71. On at least one face side of the panel body 70, a circumferential part welding coating 81 and an internal center area welding coating 82 made of corrosion resistant alloy are formed. The finned tube 60 is provided with a tube body part 61 for a cooling water passage and a pair of fin parts 62 formed on both sides of the tube body part 61 and extended in the tube body axial direction, and an outside face of a switch part 63 is formed into a recessed curving face with a radius of curvature of 3-6 mm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a boiler water wall panel that constitutes a furnace housing with a cooling water channel.
The boiler water wall panel is a plate-tube composite panel and is used as an element member when forming a wall panel of a furnace (combustion chamber / heat exchanger) housing that hits the heart of a 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.

  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 the 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 addition, in this specification, a cross section points out the cross section orthogonal to a pipe-axis direction.

  The number of the metal tube portions 21 and the metal plate portions 22 that are necessary to form a panel by being alternately arranged is individually made, and the lengths are aligned at that time (see FIGS. 3A and 3B). ). Then (see FIG. 3C), the first metal plate portion 22 is attached to the side of the first metal tube portion 21 in a state of extending in the axial direction of the tube body, and one long side of the metal plate portion 22 and the metal tube. The peripheral surface of the portion 21 is welded in a line, and the next metal plate portion 22 is attached to the other side of the first metal tube portion 21 so as to extend in the axial direction of the tube body. One long side of the 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 aligned. In this state, the other long side of the metal plate portion 22 and the peripheral surface of the metal tube portion 21 are welded in a line, and the same welded connection is repeated to form a panel body with a water channel that is a base material of the water-cooled panel segment 20. Can do.

Furthermore, a self-fluxing alloy-based coating made of a self-fluxing alloy-based material such as a Ni—Cr group is formed on one or both sides of each panel body with a water channel, thereby completing the water-cooled panel segment 20. The coating is formed by a thermal spraying-fusing treatment method. Specifically, a coating material layer is formed on the outer surface of the water-cooled panel segment 20 by a thermal spraying method, and then it is subjected to a fusing treatment. .
Due to such a manufacturing method, the base material of the water-cooled panel segment 20 has a welding structure in which a switching portion 23 from the metal tube portion 21 to the metal plate portion 22 is formed by welding.

  Another manufacturing method and structure include water-cooled panel segment unit by forming a self-fluxing alloy protective coating on the outer surface of a finned tube body with metal plate vertical fins on both sides of the metal tube. There is known a panel manufacturing method in which a plurality of bodies are made into water-cooled panel segments by mutual welding connection at the tips of vertical fins (see, for example, Patent Document 2). The structure and manufacturing method of this water cooling panel segment 50 (boiler water wall panel) will be described with reference to the drawings. 4A is a side view of the metal tube 31 and the vertical fin 32, FIG. 4B is a cross-sectional view thereof, FIG. 4C is a cross-sectional view of the finned tube body 30, and FIG. 4D is for a water-cooled panel segment. The side view of the unit member 40, (e) is the cross-sectional view, (f) is a cross-sectional view of the water-cooled panel segment 50.

  In this case as well, the metal pipe 31 serving as the cooling water channel and the vertical fin 32 serving as the web are a pair of one and two, but are separately formed (FIGS. 4A and 4B). See), the lengths of the groups required for the water-cooled panel segment 50 are aligned. And (refer FIG.4 (c)), for each group, a pair of vertical fin 32 is attached to the both sides of the metal pipe 31 in the state extended in a pipe body axial direction, and one long side of the vertical fin 32 and a metal pipe are attached. The peripheral surface of 31 is welded in a line to form a finned tube body 30 having a metal tube 31 and a pair of vertical fins 32 provided on both sides thereof and extending in the tube 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.

  Then (see FIGS. 4D and 4E), a self-fluxing alloy coating 41 made of a self-fluxing alloy material such as a Ni—Cr group is formed on one surface of each finned tube 30. Thus, the water cooling panel segment unit member 40 is produced. The coating is also formed by a thermal spraying-fusing treatment method, but the object to be constructed is subdivided, and it is applied individually to the water-cooled panel segment unit member 40 before assembly instead of the assembled water-cooled panel segment 50. Is called. Thereafter (see FIG. 4 (f)), the water cooling panel segment 50 is composed of the water cooling panel segment unit member 40 as a constituent unit, and a plurality of the members are welded to each other with the ends of the vertical fins 32 as joints 51. Is completed.

  In addition, although illustration is omitted, when the panel base material before the formation of the coating of the water-cooled panel segment 20 is adopted as the panel base material and the weld coating with the corrosion resistant alloy is formed on one side thereof, welding connection with another panel is performed. And a technique for making a boiler furnace panel by applying a superalloy coating to the end portion provided by welding overlaying and applying a self-fluxing alloy coating to the inner side by a spray-fusing treatment method (for example, Patent Document 3) (Refer to Fig. 2). During heating in the fusing process after thermal spraying, the boiler panel is pulled in the longitudinal direction with the traction tool while the displacement in the biaxial direction intersecting the longitudinal direction with the position forcing tool is regulated at many points. A method of manufacturing an alloy-coated boiler panel to be corrected is also known (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 tube portion 21 to the metal plate portion 22 is formed by welding.

JP 2000-329304 A JP 2001-004101 A JP-A-2005-274022 JP 2005-337623 A

  However, in such a conventional boiler water wall panel, since the switching portion from the tubular body portion to the plate-like fin portion is connected by welding, it is impossible to perform the welding. It greatly affects the good and bad of the. That is, when the boiler is used, both the tube part and the fin part are exposed to a high temperature environment, but the pipe part is cooled from the hollow with water or steam, whereas the fin part is not cooled, so the temperature at the switching site is abrupt. Gradient, that is, thermal strain driving force is generated, and due to this, the switching part becomes the part where the stress is the largest, so if the switching part is not perfectly welded, for example, pinholes, irregularities, blowholes, over If any one of lap, undercut, slag entrainment, weld crack, spatter, extreme unevenness of weld bead shape, etc., has a poor weld, it becomes a notch. As a result, the weld coating is damaged, and the corrosion of the base material occurs early.

Defects in welds are difficult to identify by visual inspection, so they must be confirmed by dye penetration testing, etc. Repairing welds where defects are found is troublesome, such as TIG welding after blasting. is there.
In addition, welding between the tube part and the plate-like fin part is more difficult to work than butt welding between the fin ends, so it is easy to have welding defects for the time required, so not only the burden of the welding work itself, The burden of subsequent inspections and repairs was also heavy.
Therefore, the boiler water wall panel configuration 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.

  The boiler water wall panel of the present invention (Claim 1) has been devised in order to solve such a problem, and is provided with a plurality of rows of pipe bodies serving as cooling water channels, a web connecting the rows, and an outermost wall. A panel body with a water channel provided with a pair of fins positioned on the outer side of the row tube body and extending in the tube axis direction is used as a base material, and at least one surface of the base material is welded with a corrosion-resistant alloy. The panel with a water channel as a base material is a metal seamless fin provided with a pair of fins connected to the pipe body in continuous phase on both sides of a single pipe body. A plurality of bodies having a single pipe as a structural unit 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. And

  Further, the boiler water wall panel of the present invention (Claim 2) is located on the outer side of the outermost row of pipes and a plurality of rows of pipes that serve as cooling water channels, and the tube line direction. A boiler water wall panel in which a metal channel panel body having a pair of fins extending in a base material is used as a base material, and at least one surface of the base material is welded with a corrosion-resistant alloy, and is a base material The panel with water channel is a metal in which 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 connected through a continuous phase. Seamless finned tube made of a web-a web assembly 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 welded to the center line position of some of the webs It has a welded structure where the part is located, And wherein the door.

  Furthermore, the boiler water wall panel of the present invention (Claim 3) is located on the outer side of the outermost row of pipes and a plurality of rows of pipes that serve as cooling water channels, and the tube direction. A boiler water wall panel in which a metal channel panel body having a pair of fins extending in a base material is used as a base material, and at least one surface of the base material is welded with a corrosion-resistant alloy, and is a base material The panel with water channel is a metal seamless finned tube in which the plurality of rows of tubes, a web connecting between the rows, and a pair of fins located on the outer side of the outermost row of tubes are connected in continuous phase. -It is characterized by having a seamless integrated structure in which the entire area of the panel body is formed only by integrating the web assembly.

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

  Moreover, the boiler water wall panel of the present invention (Claim 5) is the boiler water wall panel according to Claims 1 to 4 described above, and further includes the continuous phase constituting the base material. A seamless finned single tube or a finned tube-web assembly is manufactured by a seamless molding method such as a hot extrusion method.

  Moreover, the boiler water wall panel of the present invention (Claim 6) is the boiler water wall panel according to Claims 1 to 5, and the corrosion-resistant alloy constituting the weld coating is the panel. The frame-like region at the peripheral edge is characterized by being an alloy in which a Ni-rich Ni—Cr alloy is used as a base material and the contents of B and Si are suppressed to 0.1 and 0.5 mass% or less, respectively.

  In such a boiler water wall panel according to the present invention (Claim 1), a pair of pipe parts that can be manufactured by a hot extrusion method or the like and that extend in the axial direction of the pipe provided on both sides thereof are provided. Since the single unit pipe with a metal fin, which has a fin portion and is connected continuously as a whole with a continuous phase, as a structural unit, the switching portion from the tube portion to the fin portion does not have to be connected by welding. . Further, the welding between the fin end tips can be performed more easily than the above-mentioned switching site welding and the soundness of the welded portion is high. This reduces the burden of welding work when manufacturing the boiler water wall panel, and for the furnace housing incorporating the finished boiler water wall panel, the welded portion does not exist in the switching part, so The weld coating is released from the influence of notches due to welding variations, etc., and the weld in the center of the web that replaces this weld is formed with high soundness, so there is no need for damage to the coating and hence maintenance. The operating state is stabilized and the operating rate is improved.

Further, in the boiler water wall panel according to the present invention (Claim 2), the seamless finned pipe is equivalent to a small number of the above-mentioned seamless finned single pipes joined together in the whole continuous phase. -By using the web assembly as a structural unit, it is not necessary to connect the switching portion from the tube portion to the fin portion by welding, and welding of the fin portion tips is also reduced. As a result, the burden of welding work is further reduced during the manufacture of boiler water wall panels, and the damage to the coating of the furnace housing incorporating the boiler water wall panels is further reduced.
Therefore, according to the present invention (Claims 1 and 2), the burden of welding work at the time of manufacturing 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.

Further, in the boiler water wall panel according to the present invention (Claim 3), the seamless finned pipe is equivalent to a case where a plurality of the above-described seamless finned single pipes are joined together in the whole continuous phase. Since the entire area of the panel body is configured only by the integration of the web assembly, it is not necessary to weld the switching portion from the tube portion to the fin portion by welding, and there is no welding between the tips of the fin portions. As a result, the welding operation is eliminated from the boiler water wall panel manufacturing process, and the damage to the coating of the furnace housing incorporating the boiler water wall panel is further drastically reduced.
Therefore, according to the present invention (Claim 3), the burden of welding work at the time of manufacturing the boiler water wall panel can be wiped out, and the operating rate of the furnace housing incorporating the boiler water wall panel can be improved. it can.

  Moreover, in the boiler water wall panel of the present invention (Claim 4), the outer surface of the switching portion from the tubular body portion to the fin or web portion in the panel body is formed in a concave curved surface shape. In addition to alleviating stress concentration there, the cross-sectional shape of this part becomes a shape in which the thickness increases smoothly toward the root, so that the rigidity of this part increases and deformation due to stress decreases. The undesired influence of the stress due to the above-mentioned steep temperature gradient is reduced, and the above-mentioned preferable effect is increased. Moreover, the formation of the concave curved surface can be easily performed by a seamless molding method such as a hot extrusion method, and also contributes to a long life of a mold member used in the hot extrusion method or the like.

  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. Thereby, in the panel in which the thickness of the tube portion and the web portion is usually several mm, 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.

Further, in the boiler water wall panel of the present invention (Claim 5), the seamless single tube with fins or the finned tube-web assembly connected with the continuous phase constituting the panel base material is hot. Since it is produced by a seamless molding method such as an extrusion method, it is surely integrated with a continuous phase and is efficiently produced.
In general, the hot extrusion method is currently considered to be optimal for the production of seamless single finned pipes and seamless finned pipe-web assemblies, but if the equipment circumstances and costs are suitable, It is also possible to manufacture a seamless structural unit constituting the panel base material by a seamless molding method such as a powder sintering method, a sand mold casting method, or a centrifugal casting method.

  Moreover, in the boiler water wall panel according to the present invention (Claim 6), since the weld coating of the peripheral portion provided for welding connection keeps the blending amount of B and Si to a minimum, The thermal shock cracking susceptibility of a fully blended self-fluxing alloy material is extremely low, so even if a furnace housing is constructed by welding the boiler water wall panels together, The concerns about thermal shock cracking are largely eliminated. In addition, as a corrosion-resistant alloy having low thermal shock cracking sensitivity, the alloy according to claim 6 is excellent in cost performance or availability, but other alloys (for example, JIS 4901, 4902 or ISO 4955) are available according to various requirements. , 9723 described above) may be applied.

  An embodiment of the configuration of the boiler water wall panel and the manufacturing method thereof according to the present invention will be described with reference to the drawings. 1A is a side view of a finned tube 60, FIG. 1B is a cross-sectional view thereof, FIG. 1C is a side view of a panel base material 70, FIG. 1D is a cross-sectional view thereof, and FIG. Is a side view of the boiler water wall panel 80, and FIG. In addition, the cross section in each cross section shows the cross section orthogonal to the axial direction of the tube part 61. FIG.

  In this boiler water wall panel 80, a finned tube body 60, which is a single seamless finned metal tube, which is the smallest structural unit, is first integrally manufactured by a hot extrusion method (FIG. 1 (a ), (B)), and a plurality of such finned tube bodies 60, the lengths of which are equalized, and the ends of the fin portions 62 are welded to each other as joints 71 to form a panel with a water channel. It is manufactured by making a base material 70 (see FIGS. 1C and 1D), and then forming a welding coating with a corrosion-resistant alloy with one side of the panel base material 70 as a construction target surface. The corrosion-resistant alloy weld coating on the boiler water wall panel 80 (see FIGS. 1 (e) and (f)), for example, first, a thermal shock is applied to the frame-like region (81) at the peripheral portion of the construction target surface by a welding overlay method. An alloy that is not susceptible to cracking is applied, and an alloy having good workability by a thermal spraying-fusing treatment method, for example, Ni-based (Ni-Cr group or the like) or Co-based (Co -Cr-based self-fluxing alloys), and further, these self-fluxing alloys blended with WC and the like are applied.

  The finned tubular body 60 (see FIGS. 1A and 1B) is a metal having a tubular body portion 61 serving as a cooling water channel and a pair of fin portions 62 provided on both sides thereof and extending in the tubular body axial direction. It is a strip material, and the switching portion 63 from the tube portion 61 to the fin portion 62 is integrated by a hot extrusion method, not by 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. As the material of the finned tube 60, inexpensive rolled steel of carbon steel or low alloy steel (Cr-Mo steel or the like) is frequently used, but stainless steel, cast material, or 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 10. The thickness of the fin portion 62 is about 5 to 7 mm. As the hot extrusion method, the Ugine-Sejournet method using glass as a lubricant is widespread, but other methods may be used.

  The panel base material 70 (see FIGS. 1C and 1D) is made by welding connection 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, the parallel fins are arranged in parallel, and the tips of adjacent fin portions 62 are welded together to form 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 about 4000 to 8000 mm in length and about 400 to 1200 mm in width. The weld connection of the seam 71 in the panel base material 70 is performed by a general carbon dioxide arc welding method, a TIG welding method, or the like, but it is sufficient that the plate material and the groove of the plate material are brought into contact with each other. Since it is not necessary to carry out contact, it is easy to work and efficiency is improved, while welding defects hardly occur. In the panel base material 70 of the welded structure thus made, the butt welded fin portions 62 and 62 become a web connecting the pipe body portions 61 and 61, and a seam 71 which is a welded portion is provided at the center line position of the web. positioned.

The boiler water wall panel 80 (see FIGS. 1E and 1F) 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.
As a corrosion-resistant alloy that is not susceptible to thermal shock cracking and is used for the peripheral portion weld coating 81, a Ni-rich Ni—Cr alloy is used as a base material, and the content of boron B as a melting point lowering element is suppressed to 0.1 mass% or less. 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 can be mentioned. As a standard defining such an alloy material, in Japan, bar material JISG4901 and plate material JISG4902 are listed, and international standards include ISO4955 and ISO9723. The thickness of the peripheral edge weld coating 81 is about 1 to 3 mm.

Since the peripheral portion of the panel base material 70 is used for welding connection with other panels after becoming the boiler water wall panel 80, it is important that there is no thermal shock cracking susceptibility. Is already welded, so the ease and cost of coating are important.
As a corrosion-resistant alloy used for the inner region welding coating 82 because it is suitable for use in the thermal spraying-fusing treatment method and has good workability, a Ni—Cr based self-fluxing alloy can be mentioned. The material is composed of a Ni-rich Ni-Cr component in a majority amount. However, in order to provide brittleness preferable for thermal spraying and fusing treatment, self-fluxing action and the like so as not to be brittle. , Si content is 1 to 5 mass%, respectively. As such an alloy material, a nickel self-fluxing alloy material having a composition defined in Japanese Standard JISH8303 or International Standard ISO14920 can be cited. The thickness of the inner region weld coating 82 is normally about 0.5 to 3.0 mm. However, in the configuration of the present invention, the base material extends from the tube-fin-web switching portion to the welded portion. Therefore, if a coating having a thickness of 0.2 mm or more exists, sufficient corrosion protection is achieved.

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 heating in the panel longitudinal direction, such as an induction coil, is provided. By controlling the displacement in the biaxial direction intersecting the longitudinal direction with the position forcing tool while pulling the panel base material 70 with the pulling tool in the longitudinal direction while heating in the moving form, at many places. It is better to correct the deformation.
The boiler water wall panel 80 produced in this way is transported from the panel manufacturing factory to the boiler installation site, and is connected to the other panel and the peripheral portion by welding to be incorporated into the furnace housing.

  The configuration of the boiler water wall panel of the present invention and the manufacturing method thereof will be described with reference to the drawings. 2A is a side view of a seamless finned tube-web assembly 90, FIG. 2B is a transverse cross-sectional view thereof, and FIG. 2C is a side view of a panel base material 95 (panel body with water channel). ) Is a cross-sectional view thereof. Here, the cross section in each cross section indicates a cross section orthogonal to the axial direction of the tube portion 91.

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 as a base material, is a seamless finned tube-web assembly 90. It is a point.
The seamless finned tube-web assembly 90 includes a few rows of tubes 91, a web portion 92 connecting the rows, and a pair of fin portions 93 located further outside the outermost row of tubes. Each of them is connected in a continuous phase. Like the finned tube 60, it is integrally formed by the hot extrusion method. However, it is not a single tube like the finned tube 60, but a few as if the finned tube 60 were arranged and a part of the panel was assembled in advance. The tube part 91 of the book is contained in the state arranged in parallel in the plane.

In part, the tube portion 91 serving as a cooling water channel may be the same as the tube portion 61, the fin portion 93 may be the same as the fin portion 62, and the web portion 92 is substantially the same as the two fin portions 93. The switching portion 94 from the tubular body portion 91 to the web portion 92 or the fin portion 93 may be the same as the switching portion 63.
A few rows of tube portions 91 included in the seamless finned tube-web assembly 90 correspond to a part of the plurality of rows of tube portions 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 assemblies 90. Specifically, when the tips of adjacent fin portions 93 are welded to each other and assembled into a flat plate shape, and the fin portions 93 and 93 are formed into webs by the welding connection, a seam 96 which is a welded portion is formed. It will be located at the center line position of the web. However, since the seam 96 does not exist in the web portion 92 integrally formed with the tube portion 91 in the manufacturing stage of the seamless finned tube-web assembly 90, the panel base material 95 includes a plurality of rows of tubes serving as cooling water channels. It has a welded structure in which the welded portion is located at the center line position of some of the webs connecting the rows of the body portions 91. A pair of fin portions 93 are located on the outer side of the outermost tube body.

Similarly to the panel base material 70, the peripheral base weld cover 81 and the inner central region weld cover 82 are also applied and formed to the panel base material 95 of the welded structure thus produced, thereby forming a boiler water wall panel. The number of seams 96 in the panel base material 95 is smaller than the number of seams 71 in the panel base material 70.
The finished boiler water wall panel is also transported from the panel manufacturing plant to the boiler installation site, and is connected to the other panel by welding to the furnace housing and assembled into the furnace housing.

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 also be referred to as a modification of the above-described next embodiment. If FIG. 2 showing the structure of the panel base material of the above-described next embodiment is diverted and described, a panel base material will be described. Even seam 96 at 95 is an excluded form.

That is, by raising the number of rows of the tube portions 91 in the seamless finned tube-web assembly 90 which is the panel structural unit of the next embodiment to the number of rows of the tube portions 91 in the panel base material 95, The seamless finned tube-web assembly 90 is not a panel constituent unit but a panel whole constituent material.
This further embodiment is first useful in cases where the panel matrix is relatively narrow (e.g., 400-600 mm / 3-6 rows of tube sections). And according to improvement of assembly manufacturing skills, such as a hot extrusion method, a suitable target range will be expanded to a panel wider than this.

[Others]
In the above embodiment, the seamless finned single pipe 60 and the seamless finned pipe-web assembly 90 are manufactured by the hot extrusion method. However, the pipe is a seamless molding method instead of the hot extrusion method. Examples of the method for manufacturing the body and the 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 casting method, and a centrifugal casting method.
In the above embodiment, the peripheral portion welding coating 81 made of an alloy having low thermal shock cracking sensitivity was formed by a welding overlay method. However, when coating formation by other methods such as a thermal spraying-fusing treatment method is possible, Therefore, the peripheral edge weld coating 81 may be formed.

  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 garbage incineration power generation equipment is similar to this.

1 shows a structure of a boiler water wall panel and a manufacturing method thereof according to an embodiment of the present invention, in which (a) is a side view of a finned tubular body (single pipe with seamless fins), and (b) is a cross-sectional view thereof. , (C) is a side view of a panel base material (panel body with water channel), (d) is a cross-sectional view thereof, (e) is a side view of a boiler water wall panel, and (f) is a cross-sectional view thereof. . About other embodiment of this invention, the structure of the panel for boiler water walls, and its manufacturing method are shown, (a) is a side view of a seamless finned tube-web assembly, (b) is the cross-sectional view, (c) ) Is a side view of the panel base material (panel body with water channel), and (d) is a cross-sectional view thereof. About an example of the conventional water-cooled panel segment, (a) is a side view of a metal tube part and a metal plate part, (b) is the cross-sectional view, (c) is a cross-sectional view of a water-cooled panel segment. 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, and (d) is a cross-sectional view thereof. The side view of the unit member for water-cooling panel segments, (e) is the cross-sectional view, (f) is a cross-sectional view of the water-cooling panel segment.

Explanation of symbols

20 ... Water-cooled panel segment (boiler water wall panel),
21 ... Metal pipe part, 22 ... Metal plate part, 23 ... Switching part (welding),
30 ... Finned tube, 31 ... Metal tube,
32 ... vertical fins, 33 ... switching parts (welding),
40: Unit member for water-cooled panel segment, 41 ... Self-fluxing alloy coating,
50 ... Water-cooled panel segment (boiler water wall panel), 51 ... Joint (welding),
60 ... Finned tube (seamless single tube with fin),
61 ... Tube part, 62 ... Fin part, 63 ... Switching part (integral molding),
70 ... Panel base material (panel body with water channel), 71 ... Seam (welded part in the center of the web),
80 ... Boiler water wall panel, 81 ... Peripheral weld coating, 82 ... Middle 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 (6)

A metal water channel panel body comprising a plurality of rows of tube bodies serving as cooling water channels, a web connecting between the rows, and a pair of fins positioned on the outer side of the outermost tube body and extending in the tube axis direction. A boiler water wall panel in which a weld coating with a corrosion-resistant alloy is applied to at least one side of the base material as a base material,
The panel with a water channel as a base material is 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 as a structural unit. Is a welded structure in which the welded portion is located at the center line position of the web. A metal water channel panel body comprising a plurality of rows of tube bodies serving as cooling water channels, a web connecting between the rows, and a pair of fins positioned on the outer side of the outermost tube body and extending in the tube axis direction. A boiler water wall panel in which a weld coating with a corrosion-resistant alloy is applied to at least one side of the base material as a base material,
The panel body with a water channel as a base material is formed by connecting a few rows of tube bodies corresponding to a part of the plurality of rows, a web connecting the rows, and a pair of fins located further outside the outermost row tube bodies. Metal seamless finned tube connected in phases-a web assembly as a constituent unit, and a plurality of the units are welded to each other at the tip of the fin of the constituent unit, and the center of some of the webs A boiler water wall panel characterized by having a welded structure in which a weld is located at a line position. A metal water channel panel body comprising a plurality of rows of tube bodies serving as cooling water channels, a web connecting between the rows, and a pair of fins positioned on the outer side of the outermost tube body and extending in the tube axis direction. A boiler water wall panel in which a weld coating with a corrosion-resistant alloy is applied to at least one side of the base material as a base material,
The panel body with a water channel as a base material is a metal seam in which the plurality of rows of pipes, a web connecting the rows, and a pair of fins located on the outer side of the outermost row of pipes are connected in a continuous phase. A boiler water wall panel characterized by having a seamless integral structure in which the entire area of the panel body is formed only by integrating the finned tube and the web assembly.   It is a panel for boiler water walls as described in any one of Claims 1 thru | or 3, Comprising: Of the switching part from the said pipe body in the said panel body with a water channel which is a base material to the said fin or the said web A boiler water wall panel characterized in that an outer surface is formed in a concave curved surface shape.   The boiler water wall panel according to any one of claims 1 to 4, wherein the single tube with fins or the tube with fins without seam is connected by the continuous phase constituting the base material. The boiler water wall panel is characterized in that the assembly is manufactured by a seamless molding method such as a hot extrusion method.   The boiler water wall panel according to any one of claims 1 to 5, wherein the corrosion-resistant alloy constituting the weld coating is Ni-rich Ni in a frame-like region at a peripheral portion of the panel. A boiler water wall panel characterized in that it is an alloy containing a Cr alloy as a base material and containing B and Si in an amount of 0.1 and 0.5 mass% or less, respectively.

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