A method for manufacturing outer ring of nuclear power five-stage diaphragm

Abstract

The present invention discloses a method for manufacturing the outer ring of a nuclear power plant's fifth-stage partition, which belongs to the technical field of manufacturing nuclear power plant's fifth-stage partition. The purpose is to provide a method for manufacturing the outer ring of a nuclear power plant's fifth-stage partition, which solves the problem that existing process products are very prone to deformation after welding, which easily causes processing shortages, defects in the weld layer, and deformation of the workpiece. By optimizing the manufacturing process, each weld seam can be placed in a flat welding position, reducing the difficulty of welding for welders, and can greatly reduce the deformation of small welds, indirectly improving the processing quality. At the same time, since production does not require the use of tooling, it reduces production costs, improves production efficiency, and shortens the production cycle. The present invention is suitable for a method for manufacturing the outer ring of a nuclear power plant's fifth-stage partition.

Description

Technical Field

[0001] The invention belongs to the technical field of manufacturing nuclear power five-stage diaphragms, and in particular relates to a method for manufacturing an outer ring of a nuclear power five-stage diaphragm. Background Art

[0002] Steam turbines play an extremely important role in energy, electricity, and power engineering. The turbine diaphragm is used to secure the stationary blades (nozzles) and prevent interstage air leakage. It divides the interior of the turbine into several pressure sections, allowing steam to pass through the stationary blade cascade, converting potential energy into kinetic energy and directing steam flow into the moving blades in a prescribed direction.

[0003] The bulkheads are divided into primary, secondary, and tertiary stages. The outer ring of the fifth-stage bulkhead is more complex and larger than the primary and secondary outer rings (approximately 7 meters in diameter and 0.6 meters in height). This also requires higher standards (the outer diameter, steam path surface, and all end faces must be fully machined). Therefore, conventional manufacturing methods present numerous problems during assembly, welding, and processing. For example, conventional assembly methods: 1. Due to the large diameter and semi-circular shape of the workpiece, deformation after welding is very likely to occur. According to experience, deformation is greatest from the center plane to the 45° angle. Correction is typically performed using a combination of flames and jacks, which is labor-intensive and not always successful. 2. The workpiece requires minimal machining, making conventional assembly methods prone to undercutting. Experience has shown that overlay welding can often remedy this problem, but this approach carries significant risks, including defects in the overlay layer and potential deformation of the workpiece. Improper handling of these issues can easily result in component failure and is time-consuming and labor-intensive.

[0004] Therefore, it is of great significance to improve the manufacturing process of the outer ring of the fifth-stage partition of nuclear power plants. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for manufacturing the outer ring of a nuclear power five-stage partition, so as to solve the problem that the existing process products are very easy to deform after welding, which easily causes processing defects, defects in the weld layer, and deformation of the workpiece.

[0006] The technical solution adopted in the present invention is as follows:

[0007] A method for manufacturing a nuclear power five-stage diaphragm outer ring comprises the following steps:

[0008] (1) Incoming parts;

[0009] (2) Review whether the dimensions of the parts are in accordance with the drawings and processes;

[0010] (3) The platform is laid out and the semi-cylinder is in place. The inner and outer circle lines, the center plane and the center of the circle are marked. The center plane should retain at least 25mm of machining allowance. When laying out the platform, add 3mm to the inner radius of the semi-cylinder to leave enough post-weld shrinkage and assembly allowance. After the semi-cylinder is in place on the platform, it is fixed firmly with a block.

[0011] (4) Mark the semi-conical cylinder on the semi-cylinder to assemble it. The semi-cylinder is not machined with a stopper in the state of a component. The stopper will be machined when it is assembled into a welded assembly and will serve as the assembly reference for subsequent parts.

[0012] (5) Arrange box reinforcement and support reinforcement;

[0013] (6) Welding the side welds of the semi-cylinder and semi-conical cylinder chambers;

[0014] (7) Assemble and weld round steel on the semi-cylinder;

[0015] (8) Cleaning and grinding welds;

[0016] (9) Turning the semi-cylinder upper cover plate. Since the semi-cylinder upper stopper is not processed in the state of parts, it is used as the assembly reference surface of the cover plate during welding. During processing, the stopper depth is increased by 2mm to facilitate leveling when assembling the cover plate later;

[0017] (10) Shot blasting is performed on the inner sides of the semi-cylinder and semi-conical cylinder components to ensure cleanliness requirements;

[0018] (11) Assemble the cover plate on the semi-cylinder and semi-conical cylinder components, and weld them after confirming that the dimensions are correct. When assembling the cover plate, control the flatness within 3mm;

[0019] (12) Assemble the center face flange I on the above components and weld after confirming the size is correct; when assembling the center face flange I, install 3mm more on the other side of the center face to prevent the center face flange from being thinned during processing;

[0020] (13) When welding the remaining welds of assembled parts, layered and segmented welding is used to control welding deformation;

[0021] (14) Clean and polish welds and perform non-destructive testing;

[0022] (15) Stress relief annealing, in which the tie bars on the outer ring of the partition enter the heat treatment furnace together with the product without being removed. The tie bars are removed after the annealing is completed;

[0023] (16) Marking: Use the cover plate to level the surface, with a flatness of within 3mm. After leveling, use the inner circle of the semi-cylinder stop to determine the center of the circle, mark the machining allowance lines at various locations, then mark the center dividing line, and mark the steam inlet end line from the cover plate to the steam inlet end a ± 3mm dimension, and then mark the steam outlet end line from the steam inlet end line back to the length b; where a is the distance from the cover plate surface to the steam inlet end surface in the drawing; b is the standard distance from the steam inlet end to the steam outlet end in the drawing;

[0024] (17) Boring the center plane and the hole positions in the drawing;

[0025] (18) Assemble the upper and lower outer rings into a circle and weld the middle surface with a connecting piece;

[0026] (19) According to the drawing and the line, all dimensions are accurate, leaving a 5mm finishing allowance for the steam channel surface and a 4mm finishing allowance for the steam outlet end surface.

[0027] (20) Remove the connecting braces and weld the anti-deformation reinforcement;

[0028] (21) Assemble the stainless steel strip on the end of the semi-conical cylinder and weld it. Polish each layer after welding, and polish each layer until the metallic luster is visible. To ensure that there are no invisible defects, perform 100% PT inspection after each layer of weld is polished.

[0029] (22) Mark the outer circle of the semi-cylinder to assemble the center face flange II and the lug. Since the center face flange II drawing has a center face allowance, remove the allowance when preparing this part. Because the center face allowance of the welded part has been removed at this time, if it is not removed, the flange will be thickened beyond the tolerance;

[0030] (23) Grind the welds and perform non-destructive testing according to the technical requirements of the drawings;

[0031] (24) Check dimensions and eliminate defects.

[0032] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0033] 1. In the present invention, through the optimization of the manufacturing process, each weld can be placed in a flat welding position, reducing the difficulty of welding for welders, and can greatly reduce the deformation of small welds, indirectly improving the processing quality. At the same time, since production does not require the help of tooling, it reduces production costs, improves production efficiency, and shortens the production cycle, effectively solving the problem that existing process products are prone to deformation after welding, which easily causes processing shortages, defects in the weld layer, and deformation of the workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort, among which:

[0035] Figure 1 Schematic diagram of the semi-cylinder (including the stopper) of the present invention;

[0036] Figure 2Schematic diagram of the semi-conical cylinder (including the stainless steel strip welding groove) of the present invention;

[0037] Figure 3 Schematic diagram of round steel of the present invention;

[0038] Figure 4 Schematic diagram of the cover plate (including hole positions) of the present invention;

[0039] Figure 5 Schematic diagram of the faceted flange 1 of the present invention;

[0040] Figure 6 Schematic diagram of the stainless steel strip of the present invention;

[0041] Figure 7 Schematic diagram of the faceted flange II in the present invention;

[0042] Figure 8 is a schematic diagram of the lifting lug of the present invention;

[0043] Figure 9 It is a three-dimensional schematic diagram of the finished welded product of the present invention. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0046] It should be noted that reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition or explanation in subsequent drawings.

[0047] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" and the like indicate positions or locations based on the positions shown in the accompanying drawings, or the positions or locations in which the inventive product is typically placed when in use. These terms are intended merely to simplify the description of the present invention and do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0048] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0049] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention.

[0050] A method for manufacturing a nuclear power five-stage diaphragm outer ring comprises the following steps:

[0051] (1) Incoming parts;

[0052] (2) Review whether the dimensions of the parts are in accordance with the drawings and processes;

[0053] (3) The platform is laid out and the semi-cylinder is in place. The inner and outer circle lines, the center plane and the center of the circle are marked. The center plane should retain at least 25mm of machining allowance. When laying out the platform, add 3mm to the inner radius of the semi-cylinder to leave enough post-weld shrinkage and assembly allowance. After the semi-cylinder is in place on the platform, it is fixed firmly with a block.

[0054] (4) Mark the semi-conical cylinder on the semi-cylinder to assemble it. The semi-cylinder is not machined with a stopper in the state of a component. The stopper will be machined when it is assembled into a welded assembly and will serve as the assembly reference for subsequent parts.

[0055] (5) Arrange box reinforcement and support reinforcement;

[0056] (6) Welding the side welds of the semi-cylinder and semi-conical cylinder chambers;

[0057] (7) Assemble and weld round steel on the semi-cylinder;

[0058] (8) Cleaning and grinding welds;

[0059] (9) Turning the semi-cylinder upper cover plate. Since the semi-cylinder upper stopper is not processed in the state of parts, it is used as the assembly reference surface of the cover plate during welding. During processing, the stopper depth is increased by 2mm to facilitate leveling when assembling the cover plate later;

[0060] (10) Shot blasting is performed on the inner sides of the semi-cylinder and semi-conical cylinder components to ensure cleanliness requirements;

[0061] (11) Assemble the cover plate on the semi-cylinder and semi-conical cylinder components, and weld them after confirming that the dimensions are correct. When assembling the cover plate, control the flatness within 3mm;

[0062] (12) Assemble the center face flange I on the above components and weld after confirming the size is correct; when assembling the center face flange I, install 3mm more on the other side of the center face to prevent the center face flange from being thinned during processing;

[0063] (13) When welding the remaining welds of assembled parts, layered and segmented welding is used to control welding deformation;

[0064] (14) Clean and polish welds and perform non-destructive testing;

[0065] (15) Stress relief annealing, in which the tie bars on the outer ring of the partition enter the heat treatment furnace together with the product without being removed. The tie bars are removed after the annealing is completed;

[0066] (16) Marking: Use the cover plate to level the surface, with a flatness of within 3mm. After leveling, use the inner circle of the semi-cylinder stop to determine the center of the circle, mark the machining allowance lines at various locations, then mark the center dividing line, and mark the steam inlet end line from the cover plate to the steam inlet end a ± 3mm dimension, and then mark the steam outlet end line from the steam inlet end line back to the length b; where a is the distance from the cover plate surface to the steam inlet end surface in the drawing; b is the standard distance from the steam inlet end to the steam outlet end in the drawing;

[0067] (17) Boring the center plane and the hole positions in the drawing;

[0068] (18) Assemble the upper and lower outer rings into a circle and weld the middle surface with a connecting piece;

[0069] (19) According to the drawing and the line, all dimensions are accurate, leaving a 5mm finishing allowance for the steam channel surface and a 4mm finishing allowance for the steam outlet end surface.

[0070] (20) Remove the connecting braces and weld the anti-deformation reinforcement;

[0071] (21) Assemble the stainless steel strip on the end of the semi-conical cylinder and weld it. Polish each layer after welding, and polish each layer until the metallic luster is visible. To ensure that there are no invisible defects, perform 100% PT inspection after each layer of weld is polished.

[0072] (22) Mark the outer circle of the semi-cylinder to assemble the center face flange II and the lug. Since the center face flange II drawing has a center face allowance, remove the allowance when preparing this part. Because the center face allowance of the welded part has been removed at this time, if it is not removed, the flange will be thickened beyond the tolerance;

[0073] (23) Grind the welds and perform non-destructive testing according to the technical requirements of the drawings;

[0074] (24) Check dimensions and eliminate defects.

[0075] During the implementation of the present invention, through the optimization of the manufacturing process, each weld can be placed in a flat welding position, reducing the difficulty of welding for welders, and can greatly reduce the deformation of small welds, indirectly improving the processing quality. At the same time, since production does not require the help of tooling, it reduces production costs, improves production efficiency, and shortens the production cycle, effectively solving the problem that existing process products are prone to deformation after welding, which easily causes processing shortages, defects in the weld layer, and deformation of the workpiece.

[0076] Example 1

[0077] A method for manufacturing a nuclear power five-stage diaphragm outer ring comprises the following steps:

[0078] (1) Incoming parts;

[0079] (2) Review whether the dimensions of the parts are in accordance with the drawings and processes;

[0080] (3) The platform is laid out and the semi-cylinder is in place. The inner and outer circle lines, the center plane and the center of the circle are marked. The center plane should retain at least 25mm of machining allowance. When laying out the platform, add 3mm to the inner radius of the semi-cylinder to leave enough post-weld shrinkage and assembly allowance. After the semi-cylinder is in place on the platform, it is fixed firmly with a block.

[0081] (4) Mark the semi-conical cylinder on the semi-cylinder to assemble it. The semi-cylinder is not machined with a stopper in the state of a component. The stopper will be machined when it is assembled into a welded assembly and will serve as the assembly reference for subsequent parts.

[0082] (5) Arrange box reinforcement and support reinforcement;

[0083] (6) Welding the side welds of the semi-cylinder and semi-conical cylinder chambers;

[0084] (7) Assemble and weld round steel on the semi-cylinder;

[0085] (8) Cleaning and grinding welds;

[0086] (9) Turning the semi-cylinder upper cover plate. Since the semi-cylinder upper stopper is not processed in the state of parts, it is used as the assembly reference surface of the cover plate during welding. During processing, the stopper depth is increased by 2mm to facilitate leveling when assembling the cover plate later;

[0087] (10) Shot blasting is performed on the inner sides of the semi-cylinder and semi-conical cylinder components to ensure cleanliness requirements;

[0088] (11) Assemble the cover plate on the semi-cylinder and semi-conical cylinder components, and weld them after confirming that the dimensions are correct. When assembling the cover plate, control the flatness within 3mm;

[0089] (12) Assemble the center face flange I on the above components and weld after confirming the size is correct; when assembling the center face flange I, install 3mm more on the other side of the center face to prevent the center face flange from being thinned during processing;

[0090] (13) When welding the remaining welds of assembled parts, layered and segmented welding is used to control welding deformation;

[0091] (14) Clean and polish welds and perform non-destructive testing;

[0092] (15) Stress relief annealing, in which the tie bars on the outer ring of the partition enter the heat treatment furnace together with the product without being removed. The tie bars are removed after the annealing is completed;

[0093] (16) Marking: Use the cover plate to level the surface, with a flatness of within 3mm. After leveling, use the inner circle of the semi-cylinder stop to determine the center of the circle, mark the machining allowance lines at various locations, then mark the center dividing line, and mark the steam inlet end line from the cover plate to the steam inlet end a ± 3mm dimension, and then mark the steam outlet end line from the steam inlet end line back to the length b; where a is the distance from the cover plate surface to the steam inlet end surface in the drawing; b is the standard distance from the steam inlet end to the steam outlet end in the drawing;

[0094] (17) Boring the center plane and the hole positions in the drawing;

[0095] (18) Assemble the upper and lower outer rings into a circle and weld the middle surface with a connecting piece;

[0096] (19) According to the drawing and the line, all dimensions are accurate, leaving a 5mm finishing allowance for the steam channel surface and a 4mm finishing allowance for the steam outlet end surface.

[0097] (20) Remove the connecting braces and weld the anti-deformation reinforcement;

[0098] (21) Assemble the stainless steel strip on the end of the semi-conical cylinder and weld it. Polish each layer after welding, and polish each layer until the metallic luster is visible. To ensure that there are no invisible defects, perform 100% PT inspection after each layer of weld is polished.

[0099] (22) Mark the outer circle of the semi-cylinder to assemble the center face flange II and the lug. Since the center face flange II drawing has a center face allowance, remove the allowance when preparing this part. Because the center face allowance of the welded part has been removed at this time, if it is not removed, the flange will be thickened beyond the tolerance;

[0100] (23) Grind the welds and perform non-destructive testing according to the technical requirements of the drawings;

[0101] (24) Check dimensions and eliminate defects.

[0102] The above are the embodiments of the present invention. The foregoing are the preferred embodiments of the present invention. If the preferred implementation methods in each preferred embodiment are not obviously self-contradictory or based on a certain preferred implementation method, each preferred implementation method can be arbitrarily superimposed and used in combination. The embodiments and the specific parameters in the embodiments are only for the purpose of clearly describing the verification process of the invention, and are not intended to limit the scope of patent protection of the present invention. The scope of patent protection of the present invention is still subject to its claims. Any equivalent structural changes made by using the contents of the description and drawings of the present invention should also be included in the scope of protection of the present invention.

Claims

1. A method for manufacturing the outer ring of a nuclear power five-stage diaphragm, characterized in that: The following steps are involved: (1) Incoming parts; (2) Review whether the dimensions of the parts are in accordance with the drawings and processes; (3) The platform is laid out and the semi-cylinder is in place. The inner and outer circle lines, the center plane and the center of the circle are marked. The center plane should retain at least 25mm of machining allowance. When laying out the platform, add 3mm to the inner radius of the semi-cylinder to leave enough post-weld shrinkage and assembly allowance. After the semi-cylinder is in place on the platform, it is fixed firmly with a block. (4) Mark the semi-conical cylinder on the semi-cylinder to assemble it. The semi-cylinder is not machined with a stopper in the state of a component. The stopper will be machined when it is assembled into a welded assembly and will serve as the assembly reference for subsequent parts. (5) Arrange box reinforcement and support reinforcement; (6) Welding the side welds of the semi-cylinder and semi-conical cylinder chambers; (7) Assemble and weld round steel on the semi-cylinder; (8) Cleaning and grinding welds; (9) Turning the semi-cylinder upper cover plate. Since the semi-cylinder upper stopper is not processed in the state of parts, it is used as the assembly reference surface of the cover plate during welding. During processing, the stopper depth is increased by 2mm to facilitate leveling when assembling the cover plate later; (10) Shot blasting is performed on the inner sides of the semi-cylinder and semi-conical cylinder components to ensure cleanliness requirements; (11) Assemble the cover plate on the semi-cylinder and semi-conical cylinder components, and weld them after confirming that the dimensions are correct. When assembling the cover plate, control the flatness within 3mm; (12) Assemble the center face flange I on the above components and weld after confirming the size is correct; when assembling the center face flange I, install 3mm more on the other side of the center face to prevent the center face flange from being thinned during processing; (13) When welding the remaining welds of assembled parts, layered and segmented welding is used to control welding deformation; (14) Clean and polish welds and perform non-destructive testing; (15) Stress relief annealing, in which the tie bars on the outer ring of the partition enter the heat treatment furnace together with the product without being removed. The tie bars are removed after the annealing is completed; (16) Marking: Use the cover plate to level the surface, with a flatness of within 3mm. After leveling, use the inner circle of the semi-cylinder stop to determine the center of the circle, mark the machining allowance lines at various locations, then mark the center dividing line, and mark the steam inlet end line from the cover plate to the steam inlet end a ± 3mm dimension, and then mark the steam outlet end line from the steam inlet end line back to the length b; where a is the distance from the cover plate surface to the steam inlet end surface in the drawing; b is the standard distance from the steam inlet end to the steam outlet end in the drawing; (17) Boring the center plane and the hole positions in the drawing; (18) Assemble the upper and lower outer rings into a circle and weld the middle surface with a connecting piece; (19) According to the drawing and the line, the dimensions are accurate, and a 5mm finishing allowance is left for the steam channel surface and a 4mm finishing allowance is left for the steam outlet end surface; (20) Remove the connecting braces and weld the anti-deformation reinforcement; (21) Assemble the stainless steel strip on the end of the semi-conical cylinder and weld it. Polish each layer after welding, and polish each layer until the metallic luster is visible. To ensure that there are no invisible defects, perform 100% PT inspection after each layer of weld is polished. (22) Mark the outer circle of the semi-cylinder to assemble the center face flange II and the lug. Since the center face flange II drawing has a center face allowance, remove the allowance when preparing this part. Because the center face allowance of the welded part has been removed at this time, if it is not removed, the flange will be thickened beyond the tolerance; (23) Grind the welds and perform non-destructive testing according to the technical requirements of the drawings; (24) Check dimensions and eliminate defects.

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