A method for establishing alignment benchmark
By establishing a centering reference at the ends of the pipe plate and conical shell of the steam generator, the problem of moderate poor alignment between the pipe support plate and the pipe plate hole is solved, and the smooth installation of the heat transfer pipe and the safe operation of the equipment are achieved.
Patent Information
- Application Number
- CN202410661261.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-27
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2044-05-27
AI Technical Summary
In the prior art, the pipe support plate and the pipe plate hole of the steam generator are moderately poor, resulting in easy jamming, scratching and deformation during assembly of the heat transfer pipe, affecting the safe operation of the equipment.
By selecting the reference hole on the primary side of the tube plate, a first coordinate system is established, and an aligned second coordinate system is established at the end of the conical shell on the secondary side of the steam generator. The dot tooling is used to mark the marking points within the thickness range of the cylinder wall to form intersection points as the centering reference, and the coordinate value is optimized in combination with the laser tracker and analysis software to ensure the accuracy of the centering reference.
It has achieved accurate establishment of the centralized benchmark, reduced the cost of work and processing difficulty, avoided safety risks, and improved the installation efficiency of heat transfer pipes and the safety of equipment operation.
Smart Images
Figure CN118596055B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of steam generator centering reference, and in particular to a method for establishing a centering reference. Background Art
[0002] The tube bundle assembly of a nuclear power plant's main steam generator is the core heat exchange component of the steam generator. It serves as a physical barrier between the primary and secondary sides, and plays a vital role in the safe operation and functionality of the steam generator. The tube bundle assembly primarily consists of tube sheets, heat exchange tubes, and tube support plates. The tube sheet holes correspond to the tube holes in the tube support plates. Heat exchange tubes pass from the secondary side of the steam generator through multiple tube support plates and into the tube sheet holes, forming the steam generator's heat exchange structure. To ensure the steam generator's heat exchange efficiency, a sufficient heat exchange area and high thermal conductivity are required. Because a single heat exchange tube can often be tens of meters long, with a wall thickness of only 1.01 mm, it is typically a long, flexible tube. To ensure the proper function of the heat exchange tubes during steam generator operation and prevent them from vibration, swaying, collision, or friction, the secondary side of the heat exchange tubes is primarily supported by a support structure consisting of multiple tube support plates. According to the operating experience and structural characteristics of steam generators, heat exchange tubes are the main weak link of steam generators during in-service operation, and are prone to functional failures such as tube wall rupture, which can easily cause major safety accidents.
[0003] When passing through the tube support plate, the heat transfer tube is supported by the support bosses of the three-leaf plum blossom holes on the support plate. The clearance between the tube and the support plate hole is 0.36mm (when contacting on one side), and the clearance between the tube and the tube sheet hole is 0.25mm (when contacting on one side). The assembly clearance of the heat transfer tube is very small, which requires that the tube support plate be highly aligned with the corresponding tube sheet hole during installation. Only by ensuring high alignment between the tube support plate holes and the tube sheet holes can the heat transfer tube pass smoothly through the nine tube support plates and enter the tube sheet holes, with the outer surface of the tube intact. According to actual engineering experience, poor alignment between the tube support plate holes and the tube sheet holes can easily cause tube jamming, scratches on the outer surface of the tube, and deformation during tube insertion, seriously affecting the safe and efficient operation of the equipment. To achieve high alignment during tube support plate installation, establishing an alignment reference is particularly critical and determines the success or failure of alignment.
[0004] Therefore, a method for establishing a centering reference is provided to address the deficiencies of the prior art. Summary of the Invention
[0005] In order to overcome the deficiencies of the prior art, the present invention provides a method for establishing a centering reference, which solves the problem of accurately establishing a centering reference.
[0006] In order to achieve the above object, the present invention adopts the following technical solutions:
[0007] A method for establishing an alignment reference comprises the following steps:
[0008] S1: Select a set of reference holes on the primary side of the tube sheet;
[0009] S2: Establish the first coordinate system on the primary side of the tube sheet;
[0010] S3: At the end of the secondary cone shell of the steam generator, a second coordinate system is established that is aligned with the first coordinate system in step S2;
[0011] S4: connect the reference holes in pairs and extend them outward until they intersect with the diameter circle at the end of the secondary cone shell of the steam generator;
[0012] S5: Use a marking tool to mark points within the thickness range of the cylinder wall at the end of the secondary side cone shell of the steam generator;
[0013] S6: Connect the marked points in step S5 in pairs to form straight lines. The straight lines intersect to form an intersection point. The intersection point is the reference hole selected on the primary side of the tube sheet in step S1, that is, the established centering reference.
[0014] As a further improvement of the technical solution of the present invention, the following steps are also included:
[0015] S7: After completing the marking of the marking points in sequence, use the dotting tool to re-measure the position of the marking points, and use the analysis software to connect them in groups to calculate the coordinate value of the intersection of the connecting lines. When the deviation between the coordinate value of the intersection of the connecting lines and the coordinate value of the reference hole selected on the primary side of the tube sheet in step S1 is within the allowable range, it is determined that the established alignment reference meets the subsequent installation requirements.
[0016] As a further improvement of the technical solution of the present invention, in step S1, a laser collimation telescope is installed on the reference hole.
[0017] As a further improvement of the technical solution of the present invention, in step S2, a high-precision laser tracker is used to collect several points on the primary side of the tube sheet to establish a reference plane.
[0018] As a further improvement of the technical solution of the present invention, in step S2, the axis direction of the tube sheet from 0° to 180° is taken as the X axis;
[0019] The axis direction of the tube sheet from 90° to 270° is the Y axis, and the axis direction along the steam generator cylinder is the Z axis, and a first coordinate system is established.
[0020] As a further improvement of the technical solution of the present invention, in step S3, the laser tracker is moved to the end of the secondary side cone shell of the steam generator, and the first coordinate system in step S2 is aligned by the transfer function of the laser tracker to establish a second coordinate system.
[0021] As a further improvement of the technical solution of the present invention, in step S4, the inner diameter of the secondary side cone shell end of the steam generator is set to D1, the outer diameter is set to D2, and the diameter circle is set to D, and D1<D<D2.
[0022] As a further improvement of the technical solution of the present invention, in step S5, a target ball is placed on the dotting tool for receiving the signal sent by the laser tracker.
[0023] As a further improvement of the technical solution of the present invention, in step S5, the coordinate value of the target ball on the dotting tool is displayed in real time using analysis software. When the coordinate value is within the allowable deviation range, the dotting tool is used to mark the mark point within the wall thickness range of the cylinder.
[0024] Compared with the prior art, the present invention has the following beneficial effects:
[0025] In the method for establishing a centering reference disclosed herein, the centering reference is physically fixed to the end of the secondary cone shell of the steam generator and can be quickly and conveniently accessed by pulling a wire when needed. Establishing the centering reference does not require customizing a large-scale tooling—a laser receiving screen—or machining high-precision centering target mounting holes, thereby reducing tooling costs, machining difficulty, and operational risks. Repeated adjustments and lifting are avoided, saving resources and time, and minimizing safety risks. This method for establishing a centering reference, when combined with a dotting tooling, can establish the centering reference at an appropriate spatial location, demonstrating strong applicability and versatility. This method for establishing a centering reference is characterized by its precise establishment of a centering reference. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The technology of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:
[0027] Figure 1 Schematic diagram of establishing a reference hole on the primary side of a steam generator in the method for establishing a centering reference of the present invention;
[0028] Figure 2 It is a centering reference diagram for establishing a secondary side of a steam generator in the method for establishing a centering reference of the present invention.
[0029] In the picture:
[0030] 1. Steam generator; 2. Primary side; 3. Secondary side; 4. Reference hole. DETAILED DESCRIPTION
[0031] The following will be combined with the embodiments and drawings to clearly and completely describe the concept, specific structure and technical effects of the present invention so as to fully understand the purpose, scheme and effect of the present invention. It should be noted that the embodiments and features in the embodiments of this application can be combined with each other unless there is a conflict. The same reference numerals used throughout the drawings indicate the same or similar parts.
[0032] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature or indirectly fixed or connected to the other feature. Furthermore, terms such as "upper," "lower," "left," and "right" used in this disclosure are intended solely to describe the relative positions of the components of the disclosure as shown in the accompanying drawings.
[0033] Reference Figures 1 to 2 , a method for establishing an alignment reference, comprising the following steps:
[0034] S1: Select a set of reference holes 4 on the primary side 2 of the tube sheet;
[0035] S2: Establish the first coordinate system on the primary side 2 of the tube sheet;
[0036] S3: establishing a second coordinate system aligned with the first coordinate system in step S2 at the end of the cone shell 3 on the secondary side of the steam generator 1;
[0037] S4: connect the reference holes 4 in pairs and extend them outwards until they intersect with the diameter circle of the end of the cone shell 3 on the secondary side of the steam generator 1;
[0038] S5: Marking points are made within the wall thickness range of the cylinder at the end of the cone shell 3 on the secondary side of the steam generator 1 using a marking tool;
[0039] S6: Connect the marked points in step S5 in pairs to form straight lines. The straight lines intersect to form an intersection point. The intersection point is the reference hole 4 selected on the primary side 2 of the tube sheet in step S1, that is, the established centering reference.
[0040] Among them, the centering reference is physically fixed to the end of the secondary side 3 cone shell of the steam generator 1, and can be obtained by pulling a wire when needed, which is convenient and quick; the establishment of the centering reference does not require the customization of large-scale tooling - laser receiving screen, nor does it require the processing of high-precision centering target mounting holes, which reduces the tooling cost, processing difficulty and use risk, avoids repeated adjustment and lifting, saves resources and time, and avoids safety risks; this method of establishing the centering reference can be used in conjunction with the dot tooling to establish the centering reference at a suitable position in the space, and has strong applicability and versatility.
[0041] A method for establishing an alignment reference comprises the following steps:
[0042] S1: Select a group of reference holes 4 on the primary side 2 of the tube sheet and install a laser collimation telescope; the reference holes 4 form a group of three;
[0043] S2: Use a high-precision laser tracker to collect at least 20 points on the primary side 2 of the tube sheet to establish a reference plane, and establish a first coordinate system with the axis direction of the tube sheet from 0° to 180° as the X-axis; the axis direction of the tube sheet from 90° to 270° as the Y-axis; and the axis direction along the cylinder of the steam generator 1 as the Z-axis;
[0044] S3: Move the laser tracker to the end of the cone shell 3 on the secondary side of the steam generator 1, and align the coordinate system in step S2 by using the transfer function of the laser tracker to establish a second coordinate system;
[0045] S4: Set the inner diameter of the conical shell end portion of the secondary side 3 of the steam generator 1 to D1, the outer diameter to D2, and the diameter circle to D. Connect the centers of the reference holes 4 in pairs and extend them outward until they intersect with the diameter circle D of the conical shell end portion of the secondary side 3 of the steam generator 1. D1 < D < D2. Form at least 6 intersection points and calculate the first coordinate value (x1, y1) of the intersection point.
[0046] S5: Place the target ball 7 of the laser tracker on the dotting tool, and move the dotting tool within the range of the cylinder wall thickness at the end of the secondary side cone shell 3 of the steam generator 1. Use the analysis software to display the second coordinate value (x2, y2) of the target ball 7 on the dotting tool in real time. When the second coordinate value (x2, y2) and the first coordinate value (x1, y1) are within the allowable deviation range, use the dotting tool to mark at least 6 marking points within the range of the cylinder wall thickness (refer to Figure 2 shown);
[0047] S6: According to the corresponding relationship, the marked points in step S5 are connected in pairs to form at least three straight lines. The at least three straight lines form at least three intersection points. The intersection points are the reference holes 4 selected on the primary side 2 of the tube sheet in step S1, which are the established centering references.
[0048] S7: After completing the marking of the marking points in sequence, use the dotting tool to re-measure the position of the marking points, and use the analysis software to connect them in groups to calculate the coordinate values of the intersection points of the three connecting lines. When the deviation between the coordinate values of the three intersection points and the coordinate values of the reference holes 4 selected on the primary side 2 of the tube sheet in step S1 is within the allowable range, it is determined that the established centering reference meets the subsequent installation requirements.
[0049] In one embodiment, in step S5 , the allowable deviation range between the second coordinate value ( x2 , y2 ) and the first coordinate value ( x1 , y1 ) is less than 0.05 mm.
[0050] In one embodiment, in step S7, the connections are made in groups: 3#-4# connection, 5#-2# connection, 6#-1# connection; the deviation range between the coordinate value of the intersection point and the coordinate value of the reference hole 4 is less than 0.05 mm.
[0051] For other details of the method for establishing a centering reference according to the present invention, please refer to the prior art and will not be described in detail here.
[0052] The above are merely preferred embodiments of the present invention and do not constitute any form of limitation to the present invention. Therefore, any modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.
[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.
[0054] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.
Claims
1. A method for establishing a centering reference, characterized in that: The following steps are involved: S1: Select a set of reference holes on the primary side of the tube sheet; S2: Establish the first coordinate system on the primary side of the tube sheet; S3: Establishing a second coordinate system aligned with the first coordinate system in step S2 at the end of the secondary cone shell of the steam generator; moving the laser tracker to the end of the secondary cone shell of the steam generator, and aligning the first coordinate system in step S2 by using the transfer function of the laser tracker to establish the second coordinate system; S4: Connect the reference holes in pairs and extend them outward until they intersect with the diameter circle of the secondary cone shell end of the steam generator; set the inner diameter of the secondary cone shell end of the steam generator to D1, the outer diameter to D2, and the diameter circle to D, with D1 < D < D2, connect the centers of the reference holes in pairs and extend them outward until they intersect with the diameter circle D of the secondary cone shell end of the steam generator, form several intersection points, and calculate the first coordinate values (x1, y1) of the intersection points; S5: Using a dotting tool, mark points are marked within the thickness range of the cylinder wall at the end of the secondary cone shell of the steam generator; using analysis software, the second coordinate value (x2, y2) of the target ball located on the dotting tool is displayed in real time. When the second coordinate value (x2, y2) and the first coordinate value (x1, y1) are within the allowable deviation range, the dotting tool is used to mark a number of mark points within the thickness range of the cylinder wall; S6: Connect the marked points in step S5 in pairs to form straight lines. The straight lines intersect to form an intersection point. The intersection point is the reference hole selected on the primary side of the tube sheet in step S1, that is, the established centering reference.
2. A method for establishing a centering reference according to claim 1, characterized in that: Also includes the steps: S7: After completing the marking of the marking points in sequence, use the dotting tool to re-measure the position of the marking points, and use the analysis software to connect them in groups to calculate the coordinate value of the intersection of the connecting lines. When the deviation between the coordinate value of the intersection of the connecting lines and the coordinate value of the reference hole selected on the primary side of the tube sheet in step S1 is within the allowable range, it is determined that the established alignment reference meets the subsequent installation requirements.
3. The method for establishing a centering reference according to claim 1, wherein: In step S1 , a laser collimating telescope is installed on the reference hole.
4. A method for establishing a centering reference according to claim 1, characterized in that: In step S2, a high-precision laser tracker is used to collect several points on the primary side of the tube sheet to establish a reference plane.
5. A method for establishing a centering reference according to claim 4, characterized in that: In step S2, the axis direction of the tube sheet from 0° to 180° is taken as the X axis; The axis direction of the tube sheet from 90° to 270° is the Y axis, and the axis direction along the steam generator cylinder is the Z axis, and a first coordinate system is established.
6. A method for establishing a centering reference according to claim 1, characterized in that: In step S5, a target ball is placed on the dotting tool to receive the signal sent by the laser tracker.