A low temperature wind tunnel contraction section shell assembly device and contraction section shell assembly method

Abstract

The present application provides a low-temperature wind tunnel contraction section shell assembly device and contraction section shell assembly method, wherein the circular positioning plate is installed on the center of the upper surface of the positioning platform and coincides with the center of the positioning platform; the circular ring plate is installed on the outer periphery of the upper surface of the positioning platform and is arranged concentrically with the circular positioning plate; the circular tube is vertically installed in the middle of the circular positioning plate; multiple layers of annular ribs are arranged on the inner circumferential wall of the contraction section shell at intervals along the direction of the central axis of the contraction section shell and are perpendicular to the central axis; each group of supporting structures is installed in the corresponding cavity of each layer of annular ribs, and one end is connected to the outer circumferential wall of the circular tube, and the other end is connected to the inner circumferential wall of the annular ribs; each group of longitudinal ribs is arranged between two adjacent layers of annular ribs at intervals along the circumference of the annular ribs, and the two ends are respectively connected between two adjacent layers of annular ribs. The present device and method can realize high-precision assembly of multi-component complex curved surface shells and ensure the accuracy of the inner surface of the contraction section shell.

Description

Technical Field

[0001] The present application relates to the field of wind tunnels, and in particular to a contraction section shell assembly device and a contraction section shell assembly method for a low-temperature wind tunnel. Background Art

[0002] The contraction section is a contraction duct immediately following the stable section. Its main function is to accelerate the airflow to the required speed, improve the uniformity of the airflow and appropriately reduce its turbulence intensity. The contraction section of a conventional carbon steel wind tunnel is mainly composed of a pressure shell, longitudinal annular ribs, inner thin-walled plates, flanges, etc. The longitudinal annular ribs are welded inside the pressure shell, and the inner thin-walled plates are intermittently welded on the longitudinal annular ribs to form an inner profile. The manufacturing accuracy of the longitudinal annular ribs determines the quality of the flow field. Under deep cold conditions, the operating temperature of the wind tunnel is close to -196°C, and the structure will shrink significantly during operation. If the contraction section adopts a structural design of longitudinal annular ribs + inner thin-walled plates, there is a risk of cracking in the weld and deformation of the inner thin-walled plates. Therefore, it is designed as a single-layer shell structure, the inner wall of the shell is the inner profile, and the outer wall is fully penetrated and welded with a reinforcing ring to increase rigidity. The material is austenitic stainless steel.

[0003] The austenitic stainless steel contraction curve is a bicubic curve and a quintic curve. The shell needs to be divided into multiple shell petals for forming, assembly and welding. The shell is a multi-component complex surface with high precision requirements. How to ensure the accuracy of the inner surface after the shell is assembled is one of the difficulties; austenitic stainless steel has low thermal conductivity and large thermal expansion coefficient, which leads to very large welding deformation. How to control the shell welding deformation and improve the accuracy of the inner surface is the second difficulty. Due to different structural designs, the conventional carbon steel wind tunnel contraction section manufacturing process cannot be applied to the austenitic stainless steel contraction section shell. It is urgent to develop a method for manufacturing an austenitic stainless steel contraction section shell. Summary of the invention

[0004] One of the purposes of the present application is to provide a low-temperature wind tunnel contraction section shell assembly device and a contraction section shell assembly method, aiming to improve the problem of low internal surface accuracy of the existing austenitic stainless steel contraction section shell after assembly.

[0005] The technical solution of this application is:

[0006] A low-temperature wind tunnel contraction section shell assembly device, comprising a base, multiple layers of annular ribs, multiple groups of support structures and multiple groups of longitudinal ribs, wherein the base comprises a positioning platform, an annular plate, a circular positioning plate and a circular tube; the circular positioning plate is installed on the center of the upper surface of the positioning platform and coincides with the center of the positioning platform; the annular plate is installed on the outer periphery of the upper surface of the positioning platform and is arranged concentrically with the circular positioning plate; the circular tube is vertically installed on the circular positioning plate and is arranged concentrically with the circular positioning plate; multiple layers of the annular ribs are arranged on the inner circumferential wall of the contraction section shell at intervals along the direction of the central axis of the contraction section shell and are perpendicular to the central axis; each group of the support structures is installed in the cavity of each corresponding layer of the annular ribs, and one end is connected to the outer circumferential wall of the circular tube, and the other end is connected to the inner circumferential wall of the annular ribs; each group of the longitudinal ribs is arranged between two adjacent layers of the annular ribs at intervals along the circumferential direction of the annular ribs, and the two ends are respectively connected between the two adjacent layers of the annular ribs.

[0007] As a technical solution of the present application, the positioning platform is an octagonal structure and includes a positioning frame, four second H-shaped steels and eight third H-shaped steels, the positioning frame includes a first full H-shaped steel, two first long H-shaped steels and four first short H-shaped steels; the circular positioning plate is installed at the center of the upper surface of the first full H-shaped steel; one end of the two first long H-shaped steels are respectively vertically welded to the middle of the two opposite outer walls of the first full H-shaped steel; the four second H-shaped steels are arranged in a square structure, and the two ends of each second H-shaped steel are respectively connected between the outer walls of the adjacent first full H-shaped steel and the first long H-shaped steel; the first short H-shaped steel corresponds to the second H-shaped steel one by one, and one end is vertically welded to the middle of the outer wall of the second H-shaped steel; the eight third H-shaped steels are arranged in a regular octagonal structure, and the two ends of each third H-shaped steel are respectively connected between the end of the adjacent first full H-shaped steel, the other end of the first long H-shaped steel, and the other end of the first short H-shaped steel.

[0008] As a technical solution of the present application, the first full H-beam, the first long H-beam, the first short H-beam, the second H-beam and the third H-beam are all on the same plane; the diameter of the inscribed circle of the regular octagon formed by the eight third H-beams is the same as the inner diameter of the circular ring plate.

[0009] As a technical solution of the present application, multiple layers of the annular ribs are sequentially installed on the corresponding reinforcement rings, inlets and outlets on the contraction section shell, and the outer wall surfaces of all the annular ribs in the thickness direction are in contact with the inner wall surface of the contraction section shell.

[0010] As a technical solution of the present application, the annular ribs are symmetrical with respect to the central axis of the contraction section shell, and the four sides of the annular ribs are straight sides and the four corner ends are arc-shaped; the diameter of the annular ribs gradually decreases from the entrance to the exit of the contraction section shell; the annular ribs are cut by laser and have a width of 300 to 400 mm.

[0011] As a technical solution of the present application, each group of the support structure includes eight I-beams, and the eight I-beams are distributed at intervals along the circumference of the outer wall of the circular tube, and one end of each of the I-beams is connected to the outer wall of the circular tube, and the other end is connected to the annular rib.

[0012] As a technical solution of the present application, four of the I-beams in each group of the supporting structures are installed at the position of the cross axis of the annular ribs, and the other four I-beams are respectively installed at the positions of the lines connecting the centers of the circles on the arcs at the four corner ends of the annular ribs and the intersection points of the cross axis of the annular ribs.

[0013] As a technical solution of the present application, the width of the circular ring plate is 300-500 mm; the diameter of the circular positioning plate is 600-1000 mm, and the thickness is the same as the thickness of the circular ring plate; the outer diameter of the round tube is 500-800 mm.

[0014] As a technical solution of the present application, the contraction section shell is assembled in sequence through multiple layers of segmented shells in a direction gradually approaching the outlet, and there is a circumferential weld between adjacent segmented shells; each layer of the segmented shell is assembled in sequence through multiple shell petals along the circumferential direction, and there is a longitudinal weld between adjacent shell petals; wherein multiple longitudinal ribs are installed at a position 60 to 65 mm away from both sides of the longitudinal weld, and another multiple longitudinal ribs are installed near the center position of each shell petal.

[0015] As a technical solution of the present application, the outer wall surface of the longitudinal rib in the length direction is in contact with the inner wall surface of the segmented shell, and the upper end of the longitudinal rib is connected to the lower surface of the annular rib of the upper layer, and the lower end is connected to the upper surface of the annular rib of the lower layer.

[0016] A method for assembling a contraction section shell, using the above-mentioned low-temperature wind tunnel contraction section shell assembly device for assembly, comprises the following steps:

[0017] Step 1, assemble the low-temperature wind tunnel contraction section shell assembly device: assemble and weld the positioning platform, then install the circular positioning plate and the circular ring plate, adjust the elevation of the circular positioning plate and the circular ring plate to the same height and make the circular positioning plate and the circular ring plate concentric, and then spot weld the circular positioning plate and the circular ring plate on the positioning platform; find the center of the circular positioning plate and mark it, draw the cross axis of the circular positioning plate and the circular ring plate respectively, install the circular tube on the circular positioning plate, adjust the circular positioning plate and the circular ring plate to the same height, and then spot weld the circular positioning plate and the circular ring plate on the positioning platform; find the center of the circular positioning plate and mark it, draw the cross axis of the circular positioning plate and the circular ring plate respectively, install the circular tube on the circular positioning plate, and adjust the circular positioning plate and the circular ring plate to the same height. Adjust the position of the circular tube so that the center of the circular tube coincides with the center of the circular positioning plate, and make the axis of the circular tube perpendicular to the upper surface of the circular positioning plate, and then spot weld the circular tube to the circular positioning plate; take the upper surface of the circular ring plate as the zero starting point, take the cross axis of the circular positioning plate and the circular ring plate as the reference, assemble the annular ribs and the longitudinal ribs layer by layer starting from the entrance of the contraction section shell, first draw the first projection line of the outer contour of the lower surface of the first layer of the annular ribs on the concrete horizontal plane and the base, Then assemble the first layer of the annular ribs, adjust the position of the annular ribs so that the annular ribs are parallel to the circular ring plate, and align the outer contour of the lower surface of the annular ribs with the first projection line, so that the cross axis of the annular ribs coincides with the cross axis of the circular positioning plate, and finally install the first group of the supporting structures on the first layer of the annular ribs, and fix the first layer of the annular ribs; take the cross axis of the first layer of the annular ribs as a reference, draw the second projection line of the first layer of the longitudinal ribs on the upper surface of the first layer of the annular ribs, the concrete horizontal plane, and the base, and then install the first layer of the longitudinal ribs on the first layer of the annular ribs, adjust the position of the first layer of the longitudinal ribs so that the first layer of the longitudinal ribs are aligned with the corresponding second projection line, and finally spot weld the first layer of the longitudinal ribs and the first layer of the annular ribs; assemble the annular ribs, the supporting structures and the longitudinal ribs of other layers layer by layer according to the above steps until all the annular ribs, the supporting structures and the longitudinal ribs are assembled, and finally the annular ribs, the supporting structures and the longitudinal ribs are reinforced and welded;

[0018] Step 2, assembling the contraction section shell: taking the upper surface of the annular plate as the starting point, taking the cross axis of the circular positioning plate and the annular plate as the reference, assembling the shell petals of each layer layer by layer starting from the entrance of the contraction section shell; after the first layer of the shell petals are assembled, adjusting the position of the shell petals so that the inner wall surface of the shell petals fits with the outer wall surface of the annular ribs in the thickness direction and the outer wall surface of the longitudinal ribs in the length direction, and then spot welding the first layer of the shell petals to the annular ribs and the longitudinal ribs; according to the above steps, assemble the shell petals of other layers layer by layer until all the shell petals are assembled, and finally spot welding the shell petals to the corresponding annular ribs and the longitudinal ribs;

[0019] Step three, assembling the reinforcement ring on the contraction section shell: first complete the base welding of the circumferential welds between adjacent segmented shells and the longitudinal welds between adjacent shell petals, and then assemble the reinforcement ring.

[0020] Beneficial effects of this application:

[0021] The low-temperature wind tunnel contraction section shell assembly device and contraction section shell assembly method of the present application assemble the shell through the assembly device, which can achieve high-precision assembly of multi-component complex curved shells, reduce assembly difficulty, and improve assembly efficiency; at the same time, by spot welding the shell on the assembly device, the overall stiffness of the shell can be improved, the deformation and shrinkage of the shell during welding can be effectively controlled, and the post-welding accuracy of the shell can be improved; in addition, by distributing the longitudinal ribs on both sides of the longitudinal weld, the concave deformation of the shell at the longitudinal weld can be effectively controlled, thereby further improving the post-welding accuracy of the shell; further, by distributing the annular ribs on the plane where the reinforcement ring is located, the concave deformation of the shell during welding of the reinforcement ring can be effectively controlled, thereby ensuring the inner surface accuracy of the contraction section shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the implementation methods of the present application, the drawings required for use in the implementation methods will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the shell structure of the contraction section of a low-temperature wind tunnel provided in an embodiment of the present application;

[0024] Figure 2 A cross-sectional view of a low-temperature wind tunnel contraction section shell assembly device and a contraction section shell after assembly provided in an embodiment of the present application;

[0025] Figure 3 A schematic diagram of a low-temperature wind tunnel contraction section shell assembly device provided in an embodiment of the present application;

[0026] Figure 4 A schematic diagram of a base provided in an embodiment of the present application;

[0027] Figure 5 A schematic diagram of the assembled base and annular ribs provided in an embodiment of the present application;

[0028] Figure 6 A schematic diagram of the assembled base, annular ribs and support structure provided in an embodiment of the present application;

[0029] Figure 7 A schematic diagram of the shell petal assembly provided in an embodiment of the present application.

[0030] Icons: 1-contraction section shell; 2-segmented shell; 3-reinforcement ring; 4-exit; 5-base; 6-circumferential ribs; 7-support structure; 8-longitudinal ribs; 9-positioning frame; 10-circumferential plate; 11-circumferential positioning plate; 12-circumferential tube; 13-longitudinal weld; 14-shell petals; 15-circumferential weld; 16-first short H-beam; 17-second H-beam; 18-third H-beam; 19-first full H-beam; 20-first long H-beam; 21-positioning platform. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0033] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0034] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships in which the inventive product is usually placed when in use. These are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0035] In addition, in the present application, unless otherwise clearly specified and limited, the first feature being above or below the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature being above, above, and above the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being below, below, and below the second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0036] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0037] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0038] Example:

[0039] Please refer to Figure 1 , with reference Figures 2 to 7 The present application provides a low-temperature wind tunnel contraction section shell assembly device, which mainly includes a base 5, multiple layers of annular ribs 6, multiple groups of support structures 7 and multiple groups of longitudinal ribs 8. The base 5 includes a positioning platform 21, a circular ring plate 10, a circular positioning plate 11 and a circular tube 12; wherein the circular positioning plate 11 is installed on the center of the upper surface of the positioning platform 21 and coincides with the center of the positioning platform 21; at the same time, the circular ring plate 10 is installed on the outer periphery of the upper surface of the positioning platform 21 and is arranged concentrically with the circular positioning plate 11; and the circular tube 12 is vertically installed on the circular positioning plate 11. The circular positioning plate 11 is arranged concentrically with the circular positioning plate 11; in addition, multiple layers of annular ribs 6 are arranged at intervals on the inner circumferential wall of the contraction section shell 1 along the direction of the central axis of the contraction section shell 1, and are perpendicular to the central axis; each group of supporting structures 7 is installed in the cavity of each corresponding layer of annular ribs 6, and one end is connected to the outer circumferential wall of the circular tube 12, and the other end is connected to the inner circumferential wall of the annular rib 6; each group of longitudinal ribs 8 is arranged at intervals between two adjacent layers of annular ribs 6 along the circumferential direction of the annular ribs 6, and the two ends are respectively connected between two adjacent layers of annular ribs 6.

[0040] Furthermore, the positioning platform 21 is an octagonal structure and includes a positioning frame 9, four second H-shaped steels 17 and eight third H-shaped steels 18. The positioning frame 9 includes a first full H-shaped steel 19, two first long H-shaped steels 20 and four first short H-shaped steels 16; wherein the circular positioning plate 11 is installed at the center of the upper surface of the first full H-shaped steel 19; at the same time, one end of the two first long H-shaped steels 20 is respectively vertically welded to the middle of the two opposite outer side walls of the first full H-shaped steel 19; and the four second H-shaped steels 17 are arranged in a square. shaped structure, and the two ends of each second H-shaped steel 17 are respectively connected between the outer side walls of the adjacent first full H-shaped steel 19 and the first long H-shaped steel 20; the first short H-shaped steel 16 corresponds to the second H-shaped steel 17 one by one, and one end is vertically welded to the middle part of the outer side wall of the second H-shaped steel 17; the eight third H-shaped steels 18 are arranged in a regular octagonal structure, and the two ends of each third H-shaped steel 18 are respectively connected between the end of the adjacent first full H-shaped steel 19, the other end of the first long H-shaped steel 20, and the other end of the first short H-shaped steel 16.

[0041] It should be noted that the first full H-beam 19 , the first long H-beam 20 , the first short H-beam 16 , the second H-beam 17 and the third H-beam 18 are all on the same plane, and the diameter of the inscribed circle of the regular octagon surrounded by the eight third H-beams 18 is the same as the inner diameter of the circular ring plate 10 .

[0042] It should be noted that the multi-layer annular ribs 6 are sequentially installed at the corresponding reinforcing ring 3, inlet and outlet 4 on the contraction section shell 1, and the outer wall surface of all the annular ribs 6 in the thickness direction is in contact with the inner wall surface of the contraction section shell 1. The annular ribs 6 are symmetrical with respect to the central axis of the contraction section shell 1, and the four sides of the annular ribs 6 are straight sides, and the four corners are arc-shaped; the diameter of the annular ribs 6 gradually decreases from the inlet of the contraction section shell 1 to the outlet 4; the annular ribs 6 are cut by laser cutting, and the width is 300-400mm. After cutting, the outer wall surface in the thickness direction is ground by sample comparison.

[0043] Meanwhile, each group of supporting structures 7 includes eight I-beams, which are spaced apart along the circumferential direction of the outer wall of the circular tube 12, and one end of each I-beam is connected to the outer wall of the circular tube 12, and the other end is connected to the annular rib 6. In addition, four I-beams in each group of supporting structures 7 are installed at the position where the cross axis of the annular rib 6 is located, and the other four I-beams are installed at the position where the line connecting the center of the circle on the arc at the four corner ends of the annular rib 6 and the intersection point of the cross axis of the annular rib 6 is located.

[0044] It should be noted that the width of the annular plate 10 is 300-500 mm; the diameter of the circular positioning plate 11 is 600-1000 mm, and the thickness is the same as that of the annular plate 10; and the outer diameter of the circular tube 12 is 500-800 mm.

[0045] At the same time, the contraction section shell 1 is assembled in sequence through multiple layers of segmented shells 2 in a direction gradually approaching the outlet 4, and there is a circumferential weld 15 between adjacent segmented shells 2; each layer of segmented shell 2 is assembled in sequence through multiple shell petals 14 along the circumferential direction, and there is a longitudinal weld 13 between adjacent shell petals 14; wherein multiple longitudinal ribs 8 are installed at a position 60 to 65 mm away from both sides of the longitudinal weld 13, and another multiple longitudinal ribs 8 are installed near the center of each shell petal 14.

[0046] Furthermore, the outer wall surface of the longitudinal rib 8 in the length direction is in contact with the inner wall surface of the segmented shell 2, and the upper end of the longitudinal rib 8 is connected to the lower surface of the upper annular rib 6, and the lower end is connected to the upper surface of the lower annular rib 6. The longitudinal rib 8 is cut by laser cutting, and the width is 300-400 mm.

[0047] In addition, this embodiment also provides a method for assembling a contraction section shell. The method mainly uses the above low-temperature wind tunnel contraction section shell assembly device for assembly. The method mainly includes the following steps:

[0048] Step 1, assemble the low-temperature wind tunnel contraction section shell assembly device: assemble and weld the positioning platform 21 on the concrete horizontal surface, then install the circular positioning plate 11 and the circular ring plate 10, use a level to measure the elevation of the circular positioning plate 11 and the circular ring plate 10, and adjust the elevation of the circular positioning plate 11 and the circular ring plate 10 to the same height and make the circular positioning plate 11 and the circular ring plate 10 concentric, then spot weld the circular positioning plate 11 and the circular ring plate 10 on the positioning platform 21; find the center of the circular positioning plate 11 and mark it, and draw the circular positioning plate 11 and the circular ring plate 10 respectively. 1 and the cross axis of the circular ring plate 10, install the circular tube 12 on the circular positioning plate 11, adjust the position of the circular tube 12 so that the center of the circular tube 12 coincides with the center of the circular positioning plate 11, and make the axis of the circular tube 12 perpendicular to the upper surface of the circular positioning plate 11, and then spot weld the circular tube 12 on the circular positioning plate 11; take the upper surface of the circular ring plate 10 as the zero starting point, take the cross axis of the circular positioning plate 11 and the circular ring plate 10 as the reference, start to assemble the annular ribs 6 and the longitudinal ribs 8 layer by layer from the entrance of the contraction section shell 1, first draw the first layer The first projection line of the outer contour of the lower surface of the annular rib 6 on the concrete horizontal plane and the base 5, then assemble the first layer of annular ribs 6, adjust the position of the annular ribs 6 so that the annular ribs 6 are parallel to the circular ring plate 10, and align the outer contour of the lower surface of the annular ribs 6 with the first projection line, so that the cross axis of the annular ribs 6 coincides with the cross axis of the circular positioning plate 11, and finally install the first group of support structures 7 on the first layer of annular ribs 6, and fix the first layer of annular ribs 6; take the cross axis of the first layer of annular ribs 6 as the reference, on the upper surface of the first layer of annular ribs 6, on the concrete horizontal plane and on the base 5, Draw the second projection line of the first layer of longitudinal ribs 8 on the horizontal plane and the base 5, then install the first layer of longitudinal ribs 8 on the first layer of annular ribs 6, adjust the position of the first layer of longitudinal ribs 8 so that the first layer of longitudinal ribs 8 are aligned with the corresponding second projection line, and finally spot weld the first layer of longitudinal ribs 8 and the first layer of annular ribs 6; assemble the annular ribs 6, support structures 7 and longitudinal ribs 8 of other layers layer by layer according to the above steps until all the annular ribs 6, support structures 7 and longitudinal ribs 8 are assembled, and finally the annular ribs 6, support structures 7 and longitudinal ribs 8 are reinforced and welded;

[0049] Step 2, assembling the contraction section shell 1: taking the upper surface of the annular plate 10 as the starting point, taking the cross axis of the circular positioning plate 11 and the annular plate 10 as the reference, assembling the shell petals 14 of each layer layer by layer starting from the entrance of the contraction section shell 1; after the first layer of shell petals 14 are assembled, adjust the position of the shell petals 14 so that the inner wall surface of the shell petals 14 fits the outer wall surface of the annular rib 6 in the thickness direction and the outer wall surface of the longitudinal rib 8 in the length direction, and then spot weld the first layer of shell petals 14 to the annular rib 6 and the longitudinal rib 8; according to the above steps, assemble the shell petals 14 of other layers layer by layer until all the shell petals 14 are assembled, and finally spot weld the shell petals 14 to the corresponding annular rib 6 and longitudinal rib 8;

[0050] Step three, assemble the reinforcement ring 3 on the contraction section shell 1: first complete the base welding of the circumferential weld 15 between adjacent segmented shells 2 and the longitudinal weld 13 between adjacent shell petals 14, and then assemble the reinforcement ring 3; during the assembly process of the reinforcement ring 3, a grinding machine can be used to repair the web of the reinforcement ring 3 so that the web of the reinforcement ring 3 can fit the outer wall of the segmented shell 2, thereby avoiding strong assembly.

[0051] In summary, the low-temperature wind tunnel contraction section shell assembly device and the contraction section shell assembly method of the present application assemble the shell through the assembly device, which can achieve high-precision assembly of multi-component complex curved shells, reduce assembly difficulty, and improve assembly efficiency; at the same time, by spot welding the shell on the assembly device, the overall stiffness of the shell can be improved, the deformation and shrinkage of the shell during welding can be effectively controlled, the accuracy of the shell after welding can be improved, and the problem of reduced inner surface accuracy caused by deformation and shrinkage of the contraction section shell 1 after welding can be solved; in addition, by distributing the longitudinal ribs 8 on both sides of the longitudinal weld 13, the concave deformation of the shell at the longitudinal weld 13 can be effectively controlled, thereby further improving the accuracy of the shell after welding, and solving the problem of large concave deformation at the weld during welding of the contraction section shell 1; further, by distributing the annular ribs 6 on the plane where the reinforcement ring 3 is located, the concave deformation of the shell during welding of the reinforcement ring 3 can be effectively controlled, thereby ensuring the inner surface accuracy of the contraction section shell 1.

[0052] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for assembling a contraction section shell, characterized in that: The assembly is performed using a low-temperature wind tunnel contraction section shell assembly device, which includes a base, multiple layers of annular ribs, multiple groups of support structures, and multiple groups of longitudinal ribs. The base includes a positioning platform, an annular plate, a circular positioning plate, and a circular tube; the circular positioning plate is installed on the center of the upper surface of the positioning platform and coincides with the center of the positioning platform; the annular plate is installed on the outer periphery of the upper surface of the positioning platform and is concentrically arranged with the circular positioning plate; the circular tube is vertically installed on the circular positioning plate and coincides with the circular positioning plate Concentric arrangement; multiple layers of the annular ribs are arranged at intervals on the inner circumferential wall of the contraction section shell along the direction of the central axis of the contraction section shell and are perpendicular to the central axis; each group of the support structure is installed in the cavity of each corresponding layer of the annular ribs, and one end is connected to the outer circumferential wall of the circular tube, and the other end is connected to the inner circumferential wall of the annular ribs; each group of the longitudinal ribs is arranged at intervals between two adjacent layers of the annular ribs along the circumferential direction of the annular ribs, and the two ends are respectively connected between two adjacent layers of the annular ribs; the assembly method comprises the following steps: Step 1, assemble the low-temperature wind tunnel contraction section shell assembly device: assemble and weld the positioning platform, then install the circular positioning plate and the circular ring plate, adjust the elevation of the circular positioning plate and the circular ring plate to the same height and make the circular positioning plate and the circular ring plate concentric, and then spot weld the circular positioning plate and the circular ring plate on the positioning platform; find the center of the circular positioning plate and mark it, draw the cross axis of the circular positioning plate and the circular ring plate respectively, install the circular tube on the circular positioning plate, adjust the circular positioning plate and the circular ring plate to the same height, and then spot weld the circular positioning plate and the circular ring plate on the positioning platform; find the center of the circular positioning plate and mark it, draw the cross axis of the circular positioning plate and the circular ring plate respectively, install the circular tube on the circular positioning plate, and adjust the circular positioning plate and the circular ring plate to the same height. Adjust the position of the circular tube so that the center of the circular tube coincides with the center of the circular positioning plate, and make the axis of the circular tube perpendicular to the upper surface of the circular positioning plate, and then spot weld the circular tube to the circular positioning plate; take the upper surface of the circular ring plate as the zero starting point, take the cross axis of the circular positioning plate and the circular ring plate as the reference, assemble the annular ribs and the longitudinal ribs layer by layer starting from the entrance of the contraction section shell, first draw the first projection line of the outer contour of the lower surface of the first layer of the annular ribs on the concrete horizontal plane and the base, Then assemble the first layer of the annular ribs, adjust the position of the annular ribs so that the annular ribs are parallel to the circular ring plate, and align the outer contour of the lower surface of the annular ribs with the first projection line, so that the cross axis of the annular ribs coincides with the cross axis of the circular positioning plate, and finally install the first group of the supporting structures on the first layer of the annular ribs, and fix the first layer of the annular ribs; take the cross axis of the first layer of the annular ribs as a reference, draw the second projection line of the first layer of the longitudinal ribs on the upper surface of the first layer of the annular ribs, the concrete horizontal plane, and the base, and then install the first layer of the longitudinal ribs on the first layer of the annular ribs, adjust the position of the first layer of the longitudinal ribs so that the first layer of the longitudinal ribs are aligned with the corresponding second projection line, and finally spot weld the first layer of the longitudinal ribs and the first layer of the annular ribs; assemble the annular ribs, the supporting structures and the longitudinal ribs of other layers layer by layer according to the above steps until all the annular ribs, the supporting structures and the longitudinal ribs are assembled, and finally the annular ribs, the supporting structures and the longitudinal ribs are reinforced and welded; Step 2, assembling the contraction section shell: taking the upper surface of the annular plate as the starting point, taking the cross axis of the circular positioning plate and the annular plate as the reference, assembling the shell petals of each layer layer by layer starting from the entrance of the contraction section shell; after the first layer of the shell petals are assembled, adjusting the position of the shell petals so that the inner wall surface of the shell petals fits with the outer wall surface of the annular ribs in the thickness direction and the outer wall surface of the longitudinal ribs in the length direction, and then spot welding the first layer of the shell petals to the annular ribs and the longitudinal ribs; according to the above steps, assemble the shell petals of other layers layer by layer until all the shell petals are assembled, and finally spot welding the shell petals to the corresponding annular ribs and the longitudinal ribs; Step three, assembling the reinforcement ring on the contraction section shell: first complete the base welding of the circumferential welds between adjacent segmented shells and the longitudinal welds between adjacent shell petals, and then assemble the reinforcement ring.

2. The method for assembling the contraction section shell according to claim 1, characterized in that: The positioning platform is an octagonal structure and includes a positioning frame, four second H-shaped steels and eight third H-shaped steels. The positioning frame includes a first full H-shaped steel, two first long H-shaped steels and four first short H-shaped steels; the circular positioning plate is installed at the center of the upper surface of the first full H-shaped steel; one end of the two first long H-shaped steels are respectively vertically welded to the middle of the two opposite outer walls of the first full H-shaped steel; the four second H-shaped steels are arranged in a square structure, and the two ends of each second H-shaped steel are respectively connected between the outer walls of the adjacent first full H-shaped steel and the first long H-shaped steel; the first short H-shaped steel corresponds to the second H-shaped steel one by one, and one end is vertically welded to the middle of the outer wall of the second H-shaped steel; the eight third H-shaped steels are arranged in a regular octagonal structure, and the two ends of each third H-shaped steel are respectively connected between the end of the adjacent first full H-shaped steel, the other end of the first long H-shaped steel, and the other end of the first short H-shaped steel.

3. The method for assembling the contraction section shell according to claim 2, characterized in that: The first full H-beam, the first long H-beam, the first short H-beam, the second H-beam and the third H-beam are all on the same plane; the diameter of the inscribed circle of the regular octagon surrounded by the eight third H-beams is the same as the inner diameter of the circular plate.

4. The method for assembling the contraction section shell according to claim 1, characterized in that: The multiple layers of the annular ribs are sequentially installed at the corresponding reinforcing rings, inlets and outlets on the contraction section shell, and the outer wall surfaces of all the annular ribs in the thickness direction are in contact with the inner wall surface of the contraction section shell.

5. The method for assembling the contraction section shell according to claim 1, characterized in that: The annular ribs are symmetrical with respect to the central axis of the contraction section shell.

6. The method for assembling the contraction section shell according to claim 1, characterized in that: Each group of the supporting structures includes eight I-beams, which are spaced apart along the circumference of the outer wall of the circular tube, and one end of each I-beam is connected to the outer wall of the circular tube, and the other end is connected to the annular rib.

7. The method for assembling the contraction section shell according to claim 6, characterized in that: Four of the I-beams in each group of the supporting structures are installed at the position of the cross axis of the annular ribs, and the other four I-beams are installed at the positions of the lines connecting the centers of the circles on the arcs at the four corner ends of the annular ribs and the intersection points of the cross axis of the annular ribs.

8. The method for assembling the contraction section shell according to claim 1, characterized in that: The width of the circular ring plate is 300-500 mm; the diameter of the circular positioning plate is 600-1000 mm, and the thickness is the same as the thickness of the circular ring plate; the outer diameter of the circular tube is 500-800 mm.

9. The method for assembling the contraction section shell according to claim 1, characterized in that: The contraction section shell is assembled in sequence through multiple layers of segmented shells in a direction gradually approaching the outlet, and there is a circumferential weld between adjacent segmented shells; each layer of the segmented shell is assembled in sequence through multiple shell petals along the circumferential direction, and there is a longitudinal weld between adjacent shell petals; wherein multiple longitudinal ribs are installed at a position 60 to 65 mm away from both sides of the longitudinal weld, and another multiple longitudinal ribs are installed near the center of each shell petal.

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