Modular manufacturing and mounting method for large reactor equipment

Abstract

The invention discloses a large reactor equipment modular manufacturing and mounting method, which belongs to the technical field of reactor manufacturing and mounting, and comprises the following steps: S1, carrying out modular division on the overall structure of a reactor based on digital twinning, and manufacturing each part; s2, modularly mounting all parts of the reactor, and performing butt welding on every two of a reactor upper sealing head part, a reactor upper section shell pass part, a reactor middle section shell pass part, a reactor lower section shell pass part, a reactor lower sealing head part, a cooler upper section shell pass part, a cooler lower section shell pass part and a cooler lower sealing head part to form first to seventh circular seams; and S3, carrying out local heat treatment on the first to seventh circular seams to complete the installation of the reactor. According to the invention, the overall structure of the reactor is modularly divided, the position and the number of final assembly circular seams are optimized, the assembly of the large reactor is realized, the arrangement heat treatment and local heat treatment processes are matched, the residual stress is effectively eliminated, and the reliability of the reactor in the operation process is improved.

Description

Technical Field

[0001] This invention relates to the field of large reactor manufacturing and installation technology, and specifically to a modular manufacturing and installation method for large reactor equipment. Background Technology

[0002] Reactor equipment is a critical component in the petroleum and chemical industries, and its manufacturing quality directly impacts production efficiency and safe operation. Currently, reactor equipment is trending towards larger sizes, and due to limitations in diameter and length, modular, segmented assembly methods are typically employed. However, the on-site or in-plant assembly of large-scale petrochemical equipment presents numerous technical challenges, such as difficulty in controlling welding deformation of components, poor flatness of the weld overlay on tube sheets, and the difficulty and uneven elimination of residual welding stress. Furthermore, traditional manufacturing methods rely on experience and trial-and-error with physical prototypes. For such large, thick-walled, and high-precision core petrochemical containers, any deviations or defects result in extremely high repair costs and lengthy rework cycles. These problems severely affect the overall operational reliability and long-term safe operation of large reactors.

[0003] Therefore, there is an urgent need for an advanced manufacturing and installation method that can achieve precise control, reduce trial and error, and effectively eliminate residual stress in order to meet the manufacturing challenges of large reactor equipment. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes a modular manufacturing and installation method for large-scale reactor equipment.

[0005] The present invention specifically adopts the following technical solution: A modular manufacturing and installation method for a large reactor, used to assemble a reactor and a cooler into a single unit, includes the following steps: S1. Modular design and manufacturing based on digital twins; The reactor equipment is modularized, and a high-fidelity digital twin model is created for each module. This model is used to simulate and optimize the manufacturing process of each module, and the optimized process parameters guide physical manufacturing. The specific module division and manufacturing are as follows: The reactor is divided into the upper head assembly, the upper shell side assembly, the middle shell side assembly, the lower shell side assembly, and the lower head assembly from top to bottom. The cooler is divided into the upper shell side assembly, the lower shell side assembly, and the lower head assembly from top to bottom. The upper and lower heads of the reactor are respectively opened with pipe holes at preset positions and welded to the pipes and other internal and external welding parts. Then, the whole body is heat treated to obtain the upper and lower head components of the reactor. The upper and lower sections of the reactor are welded to the upper and lower tube sheets and other internal and external welded components, respectively, and then subjected to overall heat treatment to obtain the upper and lower shell-side components of the reactor. At least two reactor mid-section shell sections are butt-welded and then subjected to overall heat treatment to obtain the reactor mid-section shell-side component; The upper and lower sections of the cooler are welded to the upper and lower tube sheets of the cooler and other internal and external welded components, and then subjected to overall heat treatment to obtain the upper and lower shell-side components of the cooler. The cooler lower head is provided with connecting pipes at preset positions and then welded to the connecting pipes and other internal and external welding components. Finally, the whole assembly is heat treated to obtain the cooler lower head component. S2. Modular virtual pre-assembly and physical installation based on digital twins; In the digital twin virtual environment, all manufactured modules are pre-assembled, and the installation process is planned and verified. Physical installation is then performed according to the verified process, connecting the modules into a single unit through multiple circumferential welds. The specific installation process is as follows: The middle shell-side component of the reactor is placed horizontally. Several grid support plates are sequentially welded to the middle shell-side component of the reactor using a pre-pipe-threading positioning method. The upper and lower shell-side components of the reactor are then welded to the middle shell-side component of the reactor to form the second and third circumferential seams. Then, an automatic pipe-threading machine is used to sequentially thread the reaction tubes through the upper tube sheet of the reactor, several grid support plates, and the lower tube sheet of the cooler, so that both ends of the reaction tube bundle extend beyond the upper and lower tube sheets of the reactor. The reaction tube bundle is leveled with the upper or lower tube sheet of the reactor as the reference tube end. Finally, both ends of the reaction tube bundle are welded and expanded to the upper and lower tube sheets of the reactor, respectively. The upper and lower head components of the reactor are respectively assembled and welded to the upper and lower shell side components of the reactor to form the first and fourth circumferential seams; The upper and lower shell-side components of the cooler are placed horizontally. At least one grid support plate is welded to the upper and lower shell-side components of the cooler using a pre-pipe-threading positioning method. The upper and lower shell-side components of the cooler are then assembled and welded to form a sixth circumferential seam. Then, an automatic pipe-threading machine is used to thread the cooling pipes through the upper tube sheet, grid support plate, and lower tube sheet of the cooler in sequence, with both ends of the cooling pipe bundle extending beyond the upper and lower tube sheets of the cooler. The cooling pipe bundle is leveled with the upper or lower tube sheet of the cooler as the reference pipe end. Finally, both ends of the cooling pipe bundle are welded and expanded to the upper and lower tube sheets of the cooler, respectively. The upper and lower shell-side components of the cooler are respectively welded to the lower head components of the reactor and the lower head components of the cooler to form the fifth and seventh circumferential seams; S3. Final local heat treatment of the circumferential seam based on digital twin; Based on the welding process parameters in step S2, establish digital twin models of each circumferential seam. Then, use the digital twin models to simulate the local heat treatment process, obtain the equivalent stress cloud map of each circumferential seam after heat treatment, optimize the local heat treatment process parameters based on the simulation results, determine the optimal local heat treatment scheme, and perform local heat treatment on the first to seventh critical butt joint circumferential seams formed in step S2 according to the determined local heat treatment scheme to eliminate welding residual stress and complete the installation of the reactor.

[0006] Preferably, the manufacturing process of the upper and lower head components of the reactor is as follows: Mark the pipe holes on the upper and lower heads of the reactor and open them. Check whether the opening size is qualified. Machin the welding bevel at the opening and then carry out the penetration test. The openings of the upper and lower end caps of the reactor are aligned with the connecting pipe assembly, and then welded after preheating. Magnetic particle testing and ultrasonic testing are then performed. The upper and lower heads of the reactor are assembled with other internal and external welded parts, preheated and then welded, and then magnetic particle testing is performed to obtain the upper and lower head components of the reactor. The upper and lower end caps of the reactor were subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing were performed to verify whether the welding was qualified. The flange sealing surfaces of the upper and lower head components of the reactor and the bevels at the end of the head are precision machined, and then permeability testing and comprehensive inspection are carried out.

[0007] Preferably, the manufacturing process of the upper and lower shell-side components of the reactor is as follows: The upper and lower sections of the reactor are placed on the roller frame and aligned with the upper and lower tube sheets of the reactor according to the predetermined positions. They are then welded through preheating hot spots. The outer opening of the circumferential weld between the tube sheet and the section is then preheated and welded. The inner opening is then cleaned, ground, and subjected to magnetic particle testing. The welding is then completed after preheating again. Finally, radiographic testing, ultrasonic testing, and magnetic particle testing are performed. Draw corresponding pipe holes and open them on the upper and lower sections of the reactor, check whether the opening size is qualified, process the welding bevel at the opening, and then perform penetration testing; then assemble the pipe assembly on the upper and lower sections of the reactor, preheat and weld, and then perform magnetic particle testing and ultrasonic testing. The upper and lower sections of the reactor are assembled with other internal and external welded parts, and then welded after preheating. Magnetic particle testing is then performed to obtain the upper and lower shell-side components of the reactor. The upper and lower shell-side components of the reactor were subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing, and Brinell hardness testing were performed to verify the weld quality.

[0008] Preferably, the manufacturing process of the upper and lower shell-side components of the cooler is as follows: The upper and lower sections of the cooler are placed on the roller frame and aligned with the upper and lower tube sheets of the cooler according to the predetermined positions. They are then welded through preheating hot spots. The outer end of the circumferential weld between the tube sheet and the section is then preheated and welded. The inner end is then cleaned, ground, and subjected to magnetic particle testing. The welding is then completed after preheating again. Finally, radiographic testing, ultrasonic testing, and magnetic particle testing are performed. Draw corresponding pipe holes and open them on the upper and lower sections of the cooler, check whether the opening size is qualified, process the welding bevel at the opening, and then perform penetrant testing; then assemble the pipes on the upper and lower sections of the cooler, preheat them and weld them, and then perform magnetic particle testing and ultrasonic testing. The upper and lower sections of the cooler cylinder are assembled with other internal and external welded parts, and then welded after preheating. Magnetic particle testing is then performed to obtain the upper and lower shell-side components of the cooler. The upper and lower shell-side components of the cooler are subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing are performed to verify whether the welding is qualified.

[0009] Preferably, the manufacturing process of the lower end cap component of the cooler is as follows: Mark the pipe hole on the lower end cap of the cooler and open the hole. Check whether the opening size is qualified. Machin the welding bevel at the opening and then perform penetrant testing. Align the opening of the lower end cap of the cooler with the connecting pipe assembly, preheat and then weld, followed by magnetic particle testing and ultrasonic testing; The lower end cap of the cooler is assembled with other internal and external welded parts, preheated and then welded, and then subjected to magnetic particle testing to obtain the lower end cap component of the cooler. The lower end cap of the cooler is subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing are performed to check whether the welding is qualified. The flange sealing surface and the bevel at the end of the cooler's lower head component are precision machined, followed by penetration testing and comprehensive inspection.

[0010] Preferably, the upper and lower heads of the reactor are formed by a segmented welding process, and the specific welding process is as follows: Based on the structural parameters of the upper and lower head of the reactor, the materials of the upper and lower head of the reactor are cut into pieces by a cutting machine and pressed into arc-shaped pieces. Then, welding bevels are opened on the arc-shaped pieces and penetration testing is performed. Several arc-shaped pieces are pre-assembled using a jig and pre-hot spot welding is performed. Then, preheating and welding are carried out. After welding, post-weld overall heat treatment is performed, and magnetic particle testing, ultrasonic testing, radiographic testing and Brinell hardness testing are performed to check whether the welding is qualified. The inner surfaces of the upper and lower heads of the reactor are sandblasted, then preheated and a protective coating is welded onto the inner surface. Then, permeation and ultrasonic testing are performed, followed by overall heat treatment, and then permeation and ultrasonic testing are performed again.

[0011] Preferably, the upper and lower tube sheets of the reactor are welded together from two semi-circular tube sheets, and the specific welding process is as follows: On one side where the two semi-circular tube sheets are welded together, an asymmetrical double U-shaped bevel is set to match. The bevel is subjected to magnetic particle testing. After the magnetic particle testing is qualified, the assembly is preheated and then the welding is completed by alternating the two sides 20 to 30 times. After the welding is completed, the upper and lower tube sheets of the reactor are subjected to overall heat treatment.

[0012] Preferably, after the upper and lower tube sheets of the reactor are welded together, a protective layer needs to be deposited on the sides of the upper and lower tube sheets of the reactor. The specific steps are as follows: First, the surfaces to be welded on the upper and lower tube sheets of the reactor are machined into a "turtle back" shape, and the upper and lower tube sheets of the reactor are fixed back to back. Then, double protective layers are welded on the surfaces to be welded on the upper and lower tube sheets of the reactor respectively.

[0013] Preferably, the grid support plate includes a first support layer composed of several parallel first strips and a second support layer composed of several parallel second strips, and each of the first strips and the second strips is provided with several slots distributed along its length direction. The several first strips of the first support layer and the several second strips of the second support layer are connected to each other through the slots to form several diamond-shaped holes for the reaction tube or cooling tube to pass through.

[0014] Preferably, the first, fourth, fifth, and seventh circumferential seams are treated with a main and auxiliary heating local heat treatment process, while the second, third, and sixth seams are treated with a single heating local heat treatment process. The main and auxiliary heating local heat treatment process parameters are as follows: The main heating band is located in the first, fourth, fifth, and seventh circumferential seam areas, and its width is: ; The auxiliary heating strip is located on the side of the side tube bundle at the first, fourth, fifth, and seventh circumferential seams, and its width is: ; The process parameters for single-heat localized heat treatment are as follows: A single heating band is installed in the second, third, and sixth circumferential seam areas, and its width is: ; Furthermore, the edge temperature of a single heating zone is greater than 60%T, but does not exceed T; in, This is the serial number of the circumferential seam. For the first Width of the main heating band in the circumferential seam area For the first Width of the secondary heating band in the circumferential seam area For the first Width of a single heating band in the circumferential seam area; , The first The wall thickness of the components on both sides of the circumferential seam, in mm; This is a coefficient, with a value between 3 and 4; For the first The radius of the reactor or cooler corresponding to the annular seam area, in mm; To obtain , The maximum value in, if and If they are equal, then take the result. or T represents the heat treatment temperature, in °C.

[0015] As a preferred embodiment of the present invention, the application of the digital twin technology specifically includes: In step S1, for key processes such as segmented welding of end caps and tube sheet assembly welding, the microstructure and residual stress state required by design criteria are used as optimization objectives, and experimental test data are used as constraints. A multi-objective optimization algorithm is combined to iteratively simulate the digital twin model to obtain the optimal solution set. Then, the optimal process parameters are selected using a multi-attribute decision ranking method, forming a data-model fusion-driven autonomous decision-making system to achieve "zero trial-and-error" production. In step S2, not only is the final overall assembly simulation performed, but the parallel manufacturing and sub-assembly processes between modules are also managed. By simulating different process combination schemes, factors such as time, cost, and resource utilization are comprehensively evaluated, and the optimal, collaborative global manufacturing and assembly roadmap is output. In the subsequent stage of step S2, the module twin with actual manufacturing deviation data is imported into the virtual assembly environment to perform dynamic collision checks, hoisting path planning, tolerance accumulation analysis, and virtual simulation of complex processes such as horizontal pipe threading to ensure the safety and accuracy of the physical installation process. In step S3, for different annular seam structures, the temperature gradient and heat-affected zone of two local heat treatment processes, namely "main and auxiliary heating" and "single heating", are accurately simulated. Parameters such as heating band width, heating power, and holding time are optimized to achieve precise control of the final residual stress.

[0016] The present invention has the following beneficial effects: (1) This invention provides a modular manufacturing and installation method for large reactor equipment. By modularly dividing the overall structure of the reactor equipment, the position and number of the circumferential seams in the assembly are optimized. Combined with the overall heat treatment process after the manufacturing of each component and the local heat treatment process of the circumferential seams after the assembly of each component, the residual stress is effectively eliminated and the residual stress is evenly distributed, thus improving the reliability during operation. (2) In the manufacturing process of each component, the present invention optimizes the welding groove structure and welding method to ensure the processing accuracy of each component, thereby ensuring the assembly accuracy of each component; (3) This invention introduces digital twin technology to replace the traditional high-cost and low-efficiency physical trial and error process with a low-cost and high-efficiency virtual simulation optimization process; through multi-physics simulation, key process links are predicted and parameters are optimized, manufacturing risks are avoided in advance, the R&D cycle is shortened, and the trial production cost is reduced. (4) This invention utilizes a digital twin platform to conduct virtual pre-assembly, dynamically verify and rehearse complex assembly processes, and identify and resolve potential interference and error sources in advance; at the same time, it achieves full-process collaborative optimization of assembly paths and processes between various manufacturing modules, significantly improving on-site installation efficiency and positioning accuracy. (5) This invention constructs a digital twin model covering the entire process of design, manufacturing, heat treatment, and assembly, forming a complete "digital archive" and realizing closed-loop data management of the entire product life cycle; this mechanism can not only realize quality process tracking and responsibility traceability, but also provide strong data support for subsequent operation and maintenance, condition monitoring and life prediction. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the reactor equipment of the present invention; Figure 2 This is a schematic diagram of the welding structure of the upper and lower end caps of the reactor of the present invention; Figure 3 This is a schematic diagram of the asymmetric double U-shaped bevel joint set during the welding of the upper and lower tube sheets of the reactor of the present invention. Figure 4 This is a schematic diagram of the structure of the grille support plate of the present invention; Figure 5 This is a schematic diagram of the structure of the first strip in the grid support plate of the present invention.

[0018] The diagram is labeled as follows: 1. Reactor; 2. Cooler; 3. Upper head of reactor; 4. Upper shell side of reactor; 5. Middle shell side of reactor; 6. Lower shell side of reactor; 7. Lower head of reactor; 8. Upper shell side of cooler; 9. Lower shell side of cooler; 10. Lower head of cooler; 11. Grille support plate; 12. First slat; 13. Second slat; 14. Groove; 15. First U-shaped bevel; 16. Second U-shaped bevel. Detailed Implementation

[0019] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and specific examples.

[0020] Example 1 Reference Figure 1 This invention provides a modular manufacturing and installation method for reactor equipment. The reactor equipment includes a reactor 1 and a cooler 2, with the reactor 1 and cooler 2 assembled as a single unit. The total length of the reactor and cooler is 23030 mm, the reactor length is 17070 mm, the upper head component of the reactor has a wall thickness of 75 mm, the lower head component has a wall thickness of 95 mm, the upper, middle, and lower shell-side components of the reactor have a wall thickness of 155 mm, and the reactor diameter is 8200 mm (excluding wall thickness). The cooler length is 5860 mm, the upper shell-side component of the cooler has a wall thickness of 95 mm, the lower shell-side component of the cooler has a wall thickness of 55 mm, the lower head of the cooler has a wall thickness of 55 mm, and the cooler diameter is 4400 mm (excluding wall thickness). The specific steps include: S1. Modular Design and Intelligent Manufacturing Based on Digital Twins The reactor equipment is modularized, and a high-fidelity digital twin model containing precise geometry, materials, and physical properties is established for each module. A knowledge base of "materials-structure-process-performance" is also constructed. Simulation optimization is carried out through data-model fusion to generate an optimal set of manufacturing process parameters for each module without trial and error, and to guide physical manufacturing.

[0021] Based on the simulation results, the overall structure of the reactor equipment was divided, and each component was manufactured according to the manufacturing process parameters obtained from the simulation. Specifically, reactor 1 is divided into reactor upper head component 3, reactor upper shell side component 4, reactor middle shell side component 5, reactor lower shell side component 6, and reactor lower head component 7; cooler 2 is divided into cooler upper shell side component 8, cooler lower shell side component 9, and cooler lower head component 10. The manufacturing process for each component is as follows: The upper and lower heads of the reactor are respectively opened with pipe holes at preset positions and welded to the pipes and other internal and external welding parts. Then, the whole body is heat treated to obtain the upper and lower head components of the reactor. The upper and lower sections of the reactor are welded to the upper and lower tube sheets and other internal and external welded components, respectively, and then subjected to overall heat treatment to obtain the upper and lower shell-side components of the reactor. At least two reactor mid-section shell sections are butt-welded and then subjected to overall heat treatment to obtain the reactor mid-section shell-side component; The upper and lower sections of the cooler are welded to the upper and lower tube sheets of the cooler and other internal and external welded components, and then subjected to overall heat treatment to obtain the upper and lower shell-side components of the cooler. The cooler lower head is fitted with connecting pipes at preset positions and then welded to the connecting pipes and other internal and external welding components. After overall heat treatment, the cooler lower head component is obtained.

[0022] The overall heat treatment process for the reactor upper and lower head components, reactor upper and lower shell-side components, reactor middle shell-side components, cooler upper and lower shell-side components, and cooler lower head components is as follows: starting from room temperature, the temperature is increased to 630±10℃ at a rate not exceeding 50℃ / h, and held at this temperature for 5 hours; after the holding time, the temperature is decreased to room temperature at a rate not exceeding 50℃ / h; below 400℃, there is no limit to the rate of heating and cooling.

[0023] Specifically, the manufacturing process of the upper and lower head components of the aforementioned reactor is as follows: Mark the pipe holes on the upper and lower heads of the reactor and open them. Check whether the opening size is qualified. Machin the welding bevel at the opening and then carry out the penetration test. The openings of the upper and lower end caps of the reactor are aligned with the connecting pipe assembly, and then welded after preheating. Magnetic particle testing and ultrasonic testing are then performed. The upper and lower heads of the reactor are assembled with other internal and external welded parts, preheated and then welded, and then magnetic particle testing is performed to obtain the upper and lower head components of the reactor. The upper and lower end caps of the reactor were subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing were performed to verify whether the welding was qualified. The flange sealing surfaces of the upper and lower head components of the reactor and the bevels at the end of the head are precision machined, and then permeation testing is performed.

[0024] Additionally, refer to Figure 2 The upper and lower heads of the above-mentioned reactor are formed by segmented welding. The specific welding process is as follows: Based on the structural parameters of the upper and lower head of the reactor, the materials of the upper and lower head of the reactor are cut into pieces by a cutting machine and pressed into arc-shaped pieces. Then, welding bevels are opened on the arc-shaped pieces and penetration testing is performed. Several arc-shaped pieces are pre-assembled using a jig and pre-hot spot welding is performed. Then, preheating and welding are carried out. After welding, post-weld overall heat treatment is performed, and magnetic particle testing, ultrasonic testing, radiographic testing and Brinell hardness testing are performed to check whether the welding is qualified. The inner surfaces of the upper and lower heads of the reactor are sandblasted, then preheated and a protective coating is welded onto the inner surface. The protective coating material is 308L stainless steel and the thickness of the welded protective coating is not less than 4mm. Then, penetrant testing and ultrasonic testing are performed, followed by overall heat treatment, and then penetrant testing and ultrasonic testing are performed again.

[0025] Specifically, the manufacturing process of the upper and lower shell-side components of the aforementioned reactor is as follows: The upper and lower sections of the reactor are placed on the roller frame and aligned with the upper and lower tube sheets of the reactor according to the predetermined positions. They are then welded through a preheating hot spot. After preheating, the tube sheets and sections are welded together. After welding, X-ray inspection, ultrasonic inspection, and magnetic particle inspection are performed. Draw corresponding pipe holes and open them on the upper and lower sections of the reactor, check whether the opening size is qualified, process the welding bevel at the opening, and then perform penetration testing; then assemble the pipe assembly on the upper and lower sections of the reactor, preheat and weld, and then perform magnetic particle testing and ultrasonic testing. The upper and lower sections of the reactor are assembled with other internal and external welded parts, and then welded after preheating. Magnetic particle testing is then performed to obtain the upper and lower shell-side components of the reactor. The upper and lower shell-side components of the reactor were subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing, and Brinell hardness testing were performed to verify the weld quality.

[0026] In addition, the upper and lower tube sheets of the above-mentioned reactor are welded together from two semi-circular tube sheets. The specific welding process is as follows: First, allowances are made in the thickness direction of the two semi-circular tube sheets, and anti-deformation allowances are made during assembly to offset the deformation caused by lateral and longitudinal shrinkage during subsequent welding. Then, an asymmetrical double U-shaped bevel is set on one side where the two semi-circular tube sheets are welded together. The bevel is tested with magnetic particle. After the magnetic particle test is qualified, the assembly is preheated and then the welding is completed by alternating welding on both sides 25 times. After the welding is completed, the upper and lower tube sheets of the reactor are subjected to overall heat treatment. During the alternating welding process, the welding deformation is monitored in real time using a laser measuring instrument. When the deformation on one side exceeds 5mm, the tube sheet is flipped to the other side for welding.

[0027] The above-mentioned asymmetric double U-shaped bevel, such as Figure 3As shown, the bevel consists of a first U-shaped bevel 15 and a second U-shaped bevel 16. The lengths of the first U-shaped bevel 15 and the second U-shaped bevel 16 are not equal. The length of the second U-shaped bevel is 1 / 3 of the tube sheet wall thickness T, and the distance between the two U-shaped bevels is 10~15mm. This bevel design can control the deformation caused by transverse and longitudinal shrinkage during welding, reduce welding stress, and minimize weld metal deposition.

[0028] This embodiment optimizes deformation control by alternating double-sided welding and controlling the amount of welding deformation on each side as well as the number of flips, ensuring high precision, low deformation, and high reliability after tube sheet assembly.

[0029] After the upper and lower tube sheets of the reactor are welded together, a protective layer needs to be deposited on the sides of the upper and lower tube sheets. The specific steps are as follows: First, the surfaces to be welded on the upper and lower tube sheets of the reactor are machined into a "turtle back" shape, and the upper and lower tube sheets are fixed back to back. Then, double protective layers are welded on the surfaces to be welded on the upper and lower tube sheets respectively. During the welding process, an external magnetic field-assisted strip electrode welding technique is used. First, the first protective layer is welded on the surface to be welded on the upper tube sheet of the reactor. Then, the workpiece is flipped over, and the first protective layer is welded on the surface to be welded on the lower tube sheet of the reactor. Then, the workpiece is flipped over again, and the second protective layer is welded on the first protective layer on the upper tube sheet of the reactor. Then, the workpiece is flipped over again, and the second protective layer is welded on the first protective layer on the lower tube sheet of the reactor.

[0030] The first and second protective layers mentioned above are E309L and E308L layers, respectively, which enhance the corrosion resistance of the tube sheet. In this embodiment, the "turtleback" structure helps to evenly distribute welding stress, making the tube sheet flatter after final welding. To ensure the flatness of the tube sheet after re-welding, the tube side (the side of the tube sheet to be welded is the side closest to the tube bundle) needs to be pre-processed to the dimensions before re-welding, while the shell side only undergoes planar processing. At the same time, the thickness and diameter of the tube sheet need to be reserved for machining allowance, which is removed after welding and superposition to ensure the final dimensional accuracy. In addition, this embodiment improves the uniformity of the weld layer through a double-layer welding method, so that the flatness after welding is controlled within 3mm. During the welding process, an external magnetic field-assisted strip electrode welding technology is used, and the strip electrode width is optimized to 90mm, which improves the welding efficiency and uniformity.

[0031] Specifically, the manufacturing process of the upper and lower shell-side components of the aforementioned cooler is as follows: The upper and lower sections of the cooler are placed on the roller frame and aligned with the upper and lower tube sheets of the cooler according to the predetermined positions. They are then welded through preheating hot spots, followed by preheating and welding of the tube sheet and the section. After welding, radiographic testing, ultrasonic testing, and magnetic particle testing are performed. Draw corresponding pipe holes and open them on the upper and lower sections of the cooler, check whether the opening size is qualified, process the welding bevel at the opening, and then perform penetrant testing; then assemble the pipes on the upper and lower sections of the cooler, preheat them and weld them, and then perform magnetic particle testing and ultrasonic testing. The upper and lower sections of the cooler cylinder are assembled with other internal and external welded parts, and then welded after preheating. Magnetic particle testing is then performed to obtain the upper and lower shell-side components of the cooler. The upper and lower shell-side components of the cooler are subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing are performed to verify whether the welding is qualified.

[0032] Specifically, the manufacturing process of the lower end cap component of the aforementioned cooler is as follows: Mark the pipe hole on the lower end cap of the cooler and open the hole. Check whether the opening size is qualified. Machin the welding bevel at the opening and then perform penetrant testing. Align the opening of the lower end cap of the cooler with the connecting pipe assembly, preheat and then weld, followed by magnetic particle testing and ultrasonic testing; The lower end cap of the cooler is assembled with other internal and external welded parts, preheated and then welded, and then subjected to magnetic particle testing to obtain the lower end cap component of the cooler. The lower end cap of the cooler is subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing are performed to check whether the welding is qualified. The flange sealing surface and the bevel at the end of the cooler's lower head component are precision machined, followed by penetration testing and comprehensive inspection.

[0033] In addition, the lower end cap of the aforementioned cooler is integrally hot-pressed, and the specific molding process is as follows: According to the structural parameters of the lower end cap of the cooler, the material is cut using a CNC flame cutting machine, then hot-pressed into shape, normalized after forming, and then subjected to X-ray and ultrasonic testing, and its thickness is measured. The inner surface of the lower end cap of the cooler is sandblasted, then preheated and a protective coating is welded onto the inner surface with a thickness of not less than 4 mm. Then, penetrant testing and ultrasonic testing are performed, followed by overall heat treatment, and then penetrant testing and ultrasonic testing are performed again.

[0034] Furthermore, in step S1 above, parameters such as modular division, welding process, and heat treatment process are obtained through data-model fusion-driven process optimization based on a digital twin model, specifically as follows: By integrating historical manufacturing data, material performance experimental data, and industry standards, a comprehensive knowledge base is constructed, encompassing "material type, structural form, welding process, heat treatment process, and properties (deformation, residual stress, microstructure)." This knowledge base is then simulated and optimized within a digital twin system. Based on the simulation results, the optimal manufacturing process is determined as a guide card for each component or process, leading to physical manufacturing. Taking the tube sheet welding process as an example, the digital twin system uses "minimizing final residual stress" and "optimizing tube sheet flatness" as optimization objectives, conducting multi-objective optimization simulations. The algorithm automatically explores thousands of parameter combinations under the "asymmetric double U-groove" design, including different welding currents, speeds, alternating welding sequences on both sides, and flipping timing. After multi-attribute decision ranking of the simulation results, the system outputs an optimal, trial-and-error-free process guide card. For example, it explicitly states that "when the virtual predicted value of single-sided welding deformation reaches 5mm, immediately flip to the other side for welding," rather than relying on on-site measurements.

[0035] S2. Modular virtual pre-assembly and physical installation based on digital twins Import the manufactured modules from S1 into the virtual assembly environment. Pre-assemble all manufactured modules in the virtual environment, perform global simulation and management of the manufacturing and assembly processes for each module, and deduce different parallel manufacturing and sub-assembly sequences (e.g., some modules are pre-assembled into sub-units) to obtain and verify the optimal installation scheme. Then, based on the optimal scheme, perform physical installation, connecting the modules into a whole through multiple circumferential welds. The specific installation process is as follows: The middle shell-side component of the reactor is placed horizontally. Several grid support plates are sequentially welded to the middle shell-side component of the reactor using a pre-pipe-threading positioning method. The upper and lower shell-side components of the reactor are then welded to the middle shell-side component of the reactor to form the second and third circumferential seams. Then, an automatic pipe-threading machine is used to sequentially thread the reaction tubes through the upper tube sheet of the reactor, several grid support plates, and the lower tube sheet of the cooler, so that both ends of the reaction tube bundle extend beyond the upper and lower tube sheets of the reactor. The reaction tube bundle is leveled with the upper or lower tube sheet of the reactor as the reference tube end. Finally, both ends of the reaction tube bundle are welded and expanded to the upper and lower tube sheets of the reactor, respectively. The upper and lower head components of the reactor are respectively assembled and welded to the upper and lower shell components of the reactor to form the first and fourth circumferential seams.

[0036] The upper and lower shell-side components of the cooler are placed horizontally. The two grid support plates are welded to the upper and lower shell-side components of the cooler using a pre-pipe-threading positioning method. The upper and lower shell-side components of the cooler are then assembled and welded to form a sixth circumferential seam. Then, an automatic pipe-threading machine is used to thread the cooling pipes through the upper tube sheet, grid support plate, and lower tube sheet of the cooler in sequence, ensuring that both ends of the cooling pipe bundle extend beyond the upper and lower tube sheets of the cooler. The cooling pipe bundle is leveled using the upper or lower tube sheet as a reference pipe end. Finally, both ends of the cooling pipe bundle are welded and expanded to the upper and lower tube sheets of the cooler, respectively.

[0037] The upper and lower shell-side components of the cooler are respectively welded to the lower head components of the reactor and the lower head components of the cooler to form the fifth and seventh circumferential seams.

[0038] Specifically, refer to Figure 4 and Figure 5 The aforementioned grid support plate 11 includes a first support layer composed of several parallel first strips 12 and a second support layer composed of several parallel second strips 13. Each first strip and second strip is provided with several slots 14 distributed along its length direction. Several first strips of the first support layer and several second strips of the second support layer are interwoven and welded through the slots to form several diamond-shaped tube holes for the reaction tube or cooling tube to pass through.

[0039] The assembly process of the above-mentioned grid support plate is as follows: design and manufacture a special mold, clamp the special mold and perform milling, control the tenon and groove spacing, then clean the burrs, assemble the first strip and the second strip on the special mold, and then weld and level; then inspect each diamond tube hole through a positive tolerance gauge.

[0040] In addition, this embodiment adopts a horizontal installation method when installing the grid support plate and tube bundle, which can reduce the displacement and deformation of the grid support plate and ensure smooth tube insertion. At the same time, in order to ensure the concentricity and parallelism of the grid support plate, a pre-tube insertion positioning method is adopted when installing and fixing the grid support plate. That is, first fix one grid support plate in the middle shell-side component of the reactor, then insert at least two reaction tubes through the grid support plate for pre-positioning, and then install the other grid support plates in sequence. After all the grid support plates are installed, the pre-positioned reaction tubes are used to align the upper and lower shell-side components of the reactor with the two ends of the middle shell-side component of the reactor, that is, the tube holes of the upper and lower tube sheets of the reactor are concentric with the diamond holes of the grid support plate, thereby ensuring that the reaction tubes smoothly pass through the upper tube sheet and each grid support plate of the reactor during tube insertion.

[0041] S3. Final local heat treatment of the circumferential seam based on digital twin. Based on the welding process parameters in step S2, digital twin models of each circumferential seam are established. Then, the local heat treatment process is simulated using these digital twin models to obtain equivalent stress cloud diagrams of each circumferential seam after heat treatment. Based on the simulation results, the local heat treatment process parameters are optimized to determine the optimal local heat treatment scheme. According to the determined local heat treatment scheme, the first to seventh critical butt joint circumferential seams formed in step S2 are subjected to local heat treatment to eliminate residual welding stress and complete the reactor installation. Furthermore, when performing physical local heat treatment on the seven circumferential seams using the precise parameters optimized by simulation, temperature sensors are installed on each component for real-time temperature monitoring. The data is fed back to the twin system for comparison, achieving closed-loop control.

[0042] Specifically, when performing local heat treatment on the first to seventh circumferential seams, the first, fourth, fifth, and seventh circumferential seams adopt a main and auxiliary heating local heat treatment process, while the second, third, and sixth circumferential seams adopt a single heating local heat treatment process.

[0043] Specifically, in this embodiment, the main and auxiliary heating local heat treatment process parameters used for the first, fourth, fifth, and seventh circumferential seams are as follows: The main heating bands are located in the first, fourth, fifth, and seventh circumferential seam areas, with widths of 690mm, 750mm, 570mm, and 330mm, respectively. The auxiliary heating strips are located on the side of the first, fourth, fifth, and seventh annular seams near the side tube bundle, with widths of 345mm, 375mm, 285mm, and 165mm, respectively. The main heating element is heated to 630℃ and held for 5 hours. The auxiliary heating element is heated to 350℃, the same as the main heating element, and held for 3 hours.

[0044] The specific parameters for the single-heat localized heat treatment process used in the second, third, and sixth circumferential seams are as follows: Single heating strips are installed in the second, third, and sixth circumferential seam areas, with widths of 2392mm, 2392mm, and 1372mm respectively; The heat treatment temperature is 630℃, the holding time is 5h, and the edge temperature of a single heating band is controlled to be greater than 378℃ but not exceeding 630℃.

[0045] By employing different local heat treatment processes on the first to seventh circumferential seams, not only was the residual stress basically eliminated, but the residual stress was also evenly distributed.

[0046] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A modular manufacturing and installation method for large reactor equipment, used to assemble the reactor and cooler into one unit, characterized in that, Including the following steps: S1. Modular design and manufacturing based on digital twins; The reactor equipment was modularized, and a high-fidelity digital twin model was created for each module. This model was used to simulate and optimize the manufacturing process of each module, and the optimized process parameters guided the physical manufacturing process. The specific module division and manufacturing process are as follows: The reactor is divided into the upper head assembly, the upper shell side assembly, the middle shell side assembly, the lower shell side assembly, and the lower head assembly from top to bottom. The cooler is divided into the upper shell side assembly, the lower shell side assembly, and the lower head assembly from top to bottom. The upper and lower heads of the reactor are respectively opened with pipe holes at preset positions and welded to the pipes and other internal and external welding parts. Then, the whole body is heat treated to obtain the upper and lower head components of the reactor. The upper and lower sections of the reactor are welded to the upper and lower tube sheets and other internal and external welded components, respectively, and then subjected to overall heat treatment to obtain the upper and lower shell-side components of the reactor. At least two reactor mid-section shell sections are butt-welded and then subjected to overall heat treatment to obtain the reactor mid-section shell-side component; The upper and lower sections of the cooler are welded to the upper and lower tube sheets of the cooler and other internal and external welded components, and then subjected to overall heat treatment to obtain the upper and lower shell-side components of the cooler. The cooler lower head is provided with connecting pipes at preset positions and then welded to the connecting pipes and other internal and external welding components. Finally, the whole assembly is heat treated to obtain the cooler lower head component. S2. Modular virtual pre-assembly and physical installation based on digital twins; In the digital twin virtual environment, all manufactured modules are pre-assembled, and the installation process is planned and verified. Physical installation is then performed according to the verified process, connecting the modules into a single unit through multiple circumferential welds. The specific installation process is as follows: The middle shell-side component of the reactor is placed horizontally. Several grid support plates are sequentially welded to the middle shell-side component of the reactor using a pre-pipe-threading positioning method. The upper and lower shell-side components of the reactor are then welded to the middle shell-side component of the reactor to form the second and third circumferential seams. Then, an automatic pipe-threading machine is used to sequentially thread the reaction tubes through the upper tube sheet of the reactor, several grid support plates, and the lower tube sheet of the cooler, so that both ends of the reaction tube bundle extend beyond the upper and lower tube sheets of the reactor. The reaction tube bundle is leveled with the upper or lower tube sheet of the reactor as the reference tube end. Finally, both ends of the reaction tube bundle are welded and expanded to the upper and lower tube sheets of the reactor, respectively. The upper and lower head components of the reactor are respectively assembled and welded to the upper and lower shell side components of the reactor to form the first and fourth circumferential seams; The upper and lower shell-side components of the cooler are placed horizontally. At least one grid support plate is welded to the upper and lower shell-side components of the cooler using a pre-pipe-threading positioning method. The upper and lower shell-side components of the cooler are then assembled and welded to form a sixth circumferential seam. Then, an automatic pipe-threading machine is used to thread the cooling pipes through the upper tube sheet, grid support plate, and lower tube sheet of the cooler in sequence, with both ends of the cooling pipe bundle extending beyond the upper and lower tube sheets of the cooler. The cooling pipe bundle is leveled with the upper or lower tube sheet of the cooler as the reference pipe end. Finally, both ends of the cooling pipe bundle are welded and expanded to the upper and lower tube sheets of the cooler, respectively. The upper and lower shell-side components of the cooler are respectively welded to the lower head components of the reactor and the lower head components of the cooler to form the fifth and seventh circumferential seams; S3. Final local heat treatment of the circumferential seam based on digital twin; Based on the welding process parameters in step S2, establish digital twin models of each circumferential seam. Then, use the digital twin models to simulate the local heat treatment process, obtain the equivalent stress cloud map of each circumferential seam after heat treatment, optimize the local heat treatment process parameters based on the simulation results, determine the optimal local heat treatment scheme, and perform local heat treatment on the first to seventh critical butt joint circumferential seams formed in step S2 according to the determined local heat treatment scheme to eliminate welding residual stress and complete the installation of the reactor.

2. The modular manufacturing and installation method for a large reactor equipment according to claim 1, characterized in that, The manufacturing process of the upper and lower head components of the reactor is as follows: Mark the pipe holes on the upper and lower heads of the reactor and open them. Check whether the opening size is qualified. Machin the welding bevel at the opening and then carry out the penetration test. The openings of the upper and lower end caps of the reactor are aligned with the connecting pipe assembly, and then welded after preheating. Magnetic particle testing and ultrasonic testing are then performed. The upper and lower heads of the reactor are assembled with other internal and external welded parts, preheated and then welded, and then magnetic particle testing is performed to obtain the upper and lower head components of the reactor. The upper and lower end caps of the reactor were subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing were performed to verify whether the welding was qualified. The flange sealing surfaces of the upper and lower head components of the reactor and the bevels at the end of the head are precision machined, and then permeability testing and comprehensive inspection are carried out.

3. The modular manufacturing and installation method for a large reactor equipment according to claim 1, characterized in that, The manufacturing process of the upper and lower shell-side components of the reactor is as follows: The upper and lower sections of the reactor are placed on the roller frame and aligned with the upper and lower tube sheets of the reactor according to the predetermined positions. They are then welded through preheating hot spots. The outer opening of the circumferential weld between the tube sheet and the section is then preheated and welded. The inner opening is then cleaned, ground, and subjected to magnetic particle testing. The welding is then completed after preheating again. Finally, radiographic testing, ultrasonic testing, and magnetic particle testing are performed. Draw corresponding pipe holes and open them on the upper and lower sections of the reactor, check whether the opening size is qualified, process the welding bevel at the opening, and then perform penetration testing; then assemble the pipe assembly on the upper and lower sections of the reactor, preheat and weld, and then perform magnetic particle testing and ultrasonic testing. The upper and lower sections of the reactor are assembled with other internal and external welded parts, and then welded after preheating. Magnetic particle testing is then performed to obtain the upper and lower shell-side components of the reactor. The upper and lower shell-side components of the reactor were subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing, and Brinell hardness testing were performed to verify the weld quality.

4. The modular manufacturing and installation method for a large reactor equipment according to claim 1, characterized in that, The manufacturing process of the upper and lower shell-side components of the cooler is as follows: The upper and lower sections of the cooler are placed on the roller frame and aligned with the upper and lower tube sheets of the cooler according to the predetermined positions. They are then welded through preheating hot spots. The outer end of the circumferential weld between the tube sheet and the section is then preheated and welded. The inner end is then cleaned, ground, and subjected to magnetic particle testing. The welding is then completed after preheating again. Finally, radiographic testing, ultrasonic testing, and magnetic particle testing are performed. Draw corresponding pipe holes and open them on the upper and lower sections of the cooler, check whether the opening size is qualified, process the welding bevel at the opening, and then perform penetrant testing; then assemble the pipes on the upper and lower sections of the cooler, preheat them and weld them, and then perform magnetic particle testing and ultrasonic testing. The upper and lower sections of the cooler cylinder are assembled with other internal and external welded parts, and then welded after preheating. Magnetic particle testing is then performed to obtain the upper and lower shell-side components of the cooler. The upper and lower shell-side components of the cooler are subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing are performed to verify whether the welding is qualified.

5. The modular manufacturing and installation method for a large reactor according to claim 1, characterized in that, The manufacturing process of the lower end cap component of the cooler is as follows: Mark the pipe hole on the lower end cap of the cooler and open the hole. Check whether the opening size is qualified. Machin the welding bevel at the opening and then perform penetrant testing. Align the opening of the lower end cap of the cooler with the connecting pipe assembly, preheat and then weld, followed by magnetic particle testing and ultrasonic testing; The lower end cap of the cooler is assembled with other internal and external welded parts, preheated and then welded, and then subjected to magnetic particle testing to obtain the lower end cap component of the cooler. The lower end cap of the cooler is subjected to overall heat treatment, and magnetic particle testing, ultrasonic testing and Brinell hardness testing are performed to check whether the welding is qualified. The flange sealing surface and the bevel at the end of the cooler's lower head component are precision machined, followed by penetration testing and comprehensive inspection.

6. The modular manufacturing and installation method for a large reactor according to claim 1, characterized in that, The upper and lower heads of the reactor are formed by a segmented welding process. The specific welding process is as follows: Based on the structural parameters of the upper and lower head of the reactor, the materials of the upper and lower head of the reactor are cut into pieces by a cutting machine and pressed into arc-shaped pieces. Then, welding bevels are opened on the arc-shaped pieces and penetration testing is performed. Several arc-shaped pieces are pre-assembled using a jig and pre-hot spot welding is performed. Then, preheating and welding are carried out. After welding, post-weld overall heat treatment is performed, and magnetic particle testing, ultrasonic testing, radiographic testing and Brinell hardness testing are performed to check whether the welding is qualified. The inner surfaces of the upper and lower heads of the reactor are sandblasted, then preheated and a protective coating is welded onto the inner surface. Then, permeation and ultrasonic testing are performed, followed by overall heat treatment, and then permeation and ultrasonic testing are performed again.

7. The modular manufacturing and installation method for a large reactor according to claim 1, characterized in that, The upper and lower tube sheets of the reactor are welded together from two semi-circular tube sheets. The specific welding process is as follows: On one side where the two semi-circular tube sheets are welded together, an asymmetrical double U-shaped bevel is set to match. The bevel is subjected to magnetic particle testing. After the magnetic particle testing is qualified, the assembly is preheated and then the welding is completed by alternating the two sides 20 to 30 times. After the welding is completed, the upper and lower tube sheets of the reactor are subjected to overall heat treatment.

8. A modular manufacturing and installation method for a large reactor according to claim 7, characterized in that, After the upper and lower tube sheets of the reactor are welded together, a protective layer needs to be deposited on the sides of the upper and lower tube sheets. The specific steps are as follows: First, the surfaces to be welded on the upper and lower tube sheets of the reactor are machined into a "turtle back" shape, and the upper and lower tube sheets of the reactor are fixed back to back. Then, double protective layers are welded on the surfaces to be welded on the upper and lower tube sheets of the reactor respectively.

9. A modular manufacturing and installation method for a large reactor according to claim 1, characterized in that, The grid support plate includes a first support layer composed of several parallel first strips and a second support layer composed of several parallel second strips. Each first strip and second strip is provided with several slots distributed along its length. Several first strips of the first support layer and several second strips of the second support layer are connected to each other through the slots to form several diamond-shaped holes for the reaction tube or cooling tube to pass through.

10. A modular manufacturing and installation method for a large reactor according to claim 1, characterized in that, The first, fourth, fifth, and seventh circumferential seams adopt a main and auxiliary heating local heat treatment process, while the second, third, and sixth circumferential seams adopt a single heating local heat treatment process. The main and auxiliary heating local heat treatment process parameters are as follows: The main heating band is located in the first, fourth, fifth, and seventh circumferential seam areas, and its width is: ； The auxiliary heating strip is located on the side of the side tube bundle at the first, fourth, fifth, and seventh circumferential seams, and its width is: ； The process parameters for single-heat localized heat treatment are as follows: A single heating band is installed in the second, third, and sixth circumferential seam areas, and its width is: ； Furthermore, the edge temperature of a single heating zone is greater than 60%T, but does not exceed T; in, This is the serial number of the circumferential seam. For the first Width of the main heating band in the circumferential seam area For the first Width of the secondary heating band in the circumferential seam area For the first Width of a single heating band in the circumferential seam area; , The first The wall thickness of the components on both sides of the circumferential seam, in mm; This is a coefficient, with a value between 3 and 4; For the first The radius of the reactor or cooler corresponding to the annular seam area, in mm; To obtain , The maximum value in, if and If they are equal, then take the result. or T represents the heat treatment temperature, in °C.

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