A welding method for flow channels and guide vanes in the corner section of a large wind tunnel

Abstract

This invention belongs to the field of wind tunnel equipment construction technology and discloses a welding method for the internal flow channel and guide vanes in a corner section of a large wind tunnel. The welding method includes: preparing a bevel; preliminary assembly of the fixture; assembling the internal flow channel and guide vanes; spot welding to fix the internal flow channel and guide vanes; supplementing the assembly fixture; and final welding of the internal flow channel and guide vanes. This welding method for the internal flow channel and guide vanes in a corner section of a large wind tunnel solves the problem of the difficulty in preparing bevels for irregularly shaped curved surfaces at the contact surfaces of the internal flow channel and guide vanes, improves the rigidity of the internal flow channel and guide vanes, reduces welding deformation, and improves the manufacturing precision of the internal flow channel and guide vanes, thus possessing practical engineering value.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel equipment construction technology, specifically relating to a welding method for flow channels and guide vanes in the corner section of a large wind tunnel. Background Technology

[0002] Since the advent of wind tunnels, significant progress has been made in aerodynamic research and aircraft development using wind tunnels, and their role has become increasingly prominent. However, as test subjects (such as aircraft) become increasingly larger, conventional wind tunnel testing faces a series of severe challenges. One of these challenges is that conventional wind tunnels cannot conduct tests across the full Reynolds number range. High Reynolds number wind tunnel testing is a prerequisite and guarantee for achieving precise aerodynamic design and accurate prediction of flight performance of aircraft. Large wind tunnels were developed and developed to solve this problem.

[0003] The corner section of a large wind tunnel is more complex than that of a conventional wind tunnel. The inner flow channel is installed as the airflow profile inside the elliptical ring of the corner section, and the guide vanes are installed inside the inner flow channel and fixed by welding with the upper and lower connecting plates. To prevent the guide vanes from interfering with the structure of the inner flow channel, the guide vanes near the two ends of the inner flow channel are designed to be directly welded to the inner flow channel.

[0004] There are three difficulties in welding the inner flow channel and the guide vane: First, the contact surface between the inner flow channel and the guide vane is an irregular curved surface, making it difficult to prepare a bevel; second, the amount of welding between the inner flow channel and the guide vane is large, and the guide vane is prone to deformation after welding, which leads to a reduction in the installation accuracy of the guide vane; third, both the inner flow channel and the guide vane are complex structures, making assembly difficult and easily leading to low assembly accuracy.

[0005] Currently, there is an urgent need to develop a welding method for the flow channels and guide vanes in the corner sections of large wind tunnels. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a welding method for flow channels and guide vanes in the corner section of a large wind tunnel.

[0007] The present invention discloses a welding method for the inner flow channel and guide vane in a large wind tunnel corner section. The guide vane is a semi-arc-shaped pipe, the inner flow channel is a flat plate, and two inner flow channels are fixed at the front and rear ends of the guide vane, respectively. The contact surface between the inner flow channel and the guide vane is a bevel. The welding method includes the following steps:

[0008] S1. Prepare the beveling;

[0009] The bevels of the inner flow channel and the guide vanes are prepared using a milling machine;

[0010] S2. Preliminary assembly of tooling;

[0011] Assemble a symmetrical frame-type tooling on a steel platform; the tooling consists of 2 panels, 4 straight webs, and 2 curved webs.

[0012] During the initial assembly, the two panels are located on the top and bottom sides respectively, the two straight webs are located at the front and rear ends respectively, and the two curved webs are located in the middle, with each curved web and straight web being parallel to each other;

[0013] The lower panel is fixed to the steel platform by spot welding;

[0014] S3. Assemble the inner flow channel and guide vanes;

[0015] Assemble the inner flow channel and guide vane on the tooling; insert the guide vane into the middle section of the tooling; insert the two inner flow channels into the front and rear sections of the tooling respectively;

[0016] The lower surfaces of the edges of the two inner flow channels and the guide vanes are respectively attached to the upper surfaces of the corresponding edges on the panel; the arc surface of the outer wall of the guide vanes is attached to the arc surface of the inner wall of the arc-shaped web; the bevels of the two inner flow channels are respectively attached to the bevels of the corresponding guide vanes.

[0017] S4. Spot weld the inner flow channel and guide vanes to fix them;

[0018] The inner flow channel and guide plate are welded by tungsten inert gas welding, and the inner flow channel and guide plate are fixed to the tooling by spot welding.

[0019] S5. Supplementary assembly tools;

[0020] The remaining two straight web plates are symmetrically installed between the curved web plate and the straight web plate, positioned at the weld seam between the inner flow channel and the guide plate, and then spot-welded to the contact surfaces of the panel, the guide plate, the inner flow channel, and the curved web plate.

[0021] S6. Weld the inner flow channel and guide vanes to the cover surface;

[0022] The inner flow channel and guide plate are filled and covered by shielded metal arc welding. The tooling is then removed, and the remaining welds in the positions covered by the tooling are completed.

[0023] Furthermore, when preparing the bevel for the inner flow channel, a milling machine is used to cut the inner flow channel. The width of the cutting surface I is half the thickness t of the inner flow channel, and the cutting surface I is perpendicular to the bottom surface of the inner flow channel.

[0024] Furthermore, when preparing the bevel of the guide vane, a milling machine is used to cut the guide vane so that the width of the cut surface II is 15mm~25mm and the angle between the cut surface II and the generatrix of the guide vane surface is 40°~50°.

[0025] Furthermore, the thickness of the panel, straight web, and curved web is greater than 30 mm.

[0026] The welding method for the flow channel and guide vanes in the corner section of a large wind tunnel according to the present invention has the following characteristics:

[0027] a. The tooling structure is simple and easy to manufacture. It can assist in assembling the inner flow channel and guide vanes, reducing the assembly difficulty and improving the assembly accuracy;

[0028] b. Based on the characteristics of the contact surface between the inner flow channel and the guide vane, a reasonable bevel form was designed, which forms an X-shaped bevel after assembly, thus solving the problem of the difficulty in preparing the bevel of the irregular curved surface of the contact surface between the inner flow channel and the guide vane.

[0029] c. By spot welding the inner flow channel and guide vanes onto the tooling, the rigidity of the inner flow channel and guide vanes is improved, welding deformation is reduced, and the manufacturing accuracy of the inner flow channel and guide vanes is improved.

[0030] The welding method for the inner flow channel and guide vane in the corner section of a large wind tunnel, as described in this invention, solves the problem of the difficulty in preparing the irregular curved bevel of the contact surface between the inner flow channel and the guide vane. It improves the rigidity of the inner flow channel and the guide vane, reduces welding deformation, and improves the manufacturing accuracy of the inner flow channel and the guide vane, thus having practical engineering value. Attached Figure Description

[0031] Figure 1a A forward isometric view of the internal flow channel and guide vanes after assembly;

[0032] Figure 1b This is a rearward isometric view of the internal flow channel and guide vanes after assembly.

[0033] Figure 1c This is a side view of the internal flow channel and guide vanes after assembly.

[0034] Figure 2 Exploded view of the internal flow channel and guide vanes;

[0035] Figure 3 Schematic diagram of the preparation of the inner flow channel bevel;

[0036] Figure 4 Schematic diagram of guide vane bevel preparation;

[0037] Figure 5 This is a schematic diagram of the assembly process of the inner flow channel and the guide vanes.

[0038] In the figure, 1. Inner flow channel; 2. Guide vane; 3. Tooling; 4. Panel; 5. Straight web; 6. Curved web. Detailed Implementation

[0039] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0040] Example: The welding method for the flow channel and guide vanes in the corner section of a large wind tunnel in this example adopts the following... Figures 1a-1c , Figure 2The guide vane 2 and inner flow channel 1 are shown. The guide vane 2 is a semi-circular pipe, and the inner flow channel 1 is a flat plate. The two inner flow channels 1 are fixed at the front and rear ends of the guide vane 2, respectively. The curved surface where the inner flow channel 1 contacts the guide vane 2 is beveled. Figure 5 As shown, the welding method includes the following steps:

[0041] S1. Prepare the beveling;

[0042] The bevels of the inner flow channel 1 and the guide vane 2 are prepared using a milling machine;

[0043] S2. Preliminary assembly of tooling 3;

[0044] The tooling 3 is assembled on a steel platform in a symmetrical frame shape; the tooling 3 consists of 2 panels 4, 4 straight webs 5, and 2 curved webs 6;

[0045] During the initial assembly, the two panels 4 are located on the upper and lower sides respectively, the two straight webs 5 are located at the front and rear ends respectively, and the two curved webs 6 are located in the middle. The curved webs 6 and the straight webs 5 are parallel to each other.

[0046] The lower panel 4 is fixed to the steel platform by spot welding;

[0047] S3. Assemble the inner flow channel 1 and the guide vane 2;

[0048] Assemble the inner flow channel 1 and the guide vane 2 on the tooling 3; insert the guide vane 2 into the middle section of the tooling 3; insert the two inner flow channels 1 into the front and rear sections of the tooling 3 respectively;

[0049] The lower surfaces of the edges of the two inner flow channels 1 and the guide vane 2 are respectively attached to the upper surfaces of the corresponding edges on the panel 4; the arc surface of the outer wall of the guide vane 2 is attached to the arc surface of the inner wall of the arc-shaped web 6; the bevels of the two inner flow channels 1 are respectively attached to the bevels of the corresponding guide vane 2.

[0050] S4. Spot weld the inner flow channel 1 and the guide plate 2 to fix them;

[0051] The inner flow channel 1 and the guide plate 2 are welded by tungsten inert gas welding, and the inner flow channel 1, the guide plate 2 and the tooling 3 are fixed by spot welding.

[0052] S5. Supplementary assembly tooling 3;

[0053] The remaining two straight web plates 5 are symmetrically installed between the arc-shaped web plate 6 and the straight web plate 5, placed at the weld position between the inner flow channel 1 and the guide plate 2, and spot welded to the contact surfaces of the panel 4, the guide plate 2, the inner flow channel 1, and the arc-shaped web plate 6.

[0054] S6. Weld the inner flow channel 1 and the guide plate 2 to the cover surface;

[0055] The inner flow channel 1 and the guide plate 2 are filled and covered by shielded metal arc welding. The tooling 3 is removed and the remaining welds at the positions covered by the tooling 3 are completed.

[0056] Furthermore, such as Figure 3 As shown, when preparing the bevel of the inner flow channel 1, a milling machine is used to cut the inner flow channel 1. The width of the cutting surface I is half of the thickness t of the inner flow channel 1, and the cutting surface I is perpendicular to the bottom surface of the inner flow channel 1.

[0057] Furthermore, such as Figure 4 As shown, when preparing the bevel of the guide vane 2, a milling machine is used to cut the guide vane 2 so that the width of the cut surface II is 15mm~25mm and the angle between the cut surface II and the generatrix of the curved surface of the guide vane 2 is 40°~50°.

[0058] Furthermore, the thickness of the panel 4, the straight web 5, and the arc-shaped web 6 is all greater than 30 mm.

[0059] In this embodiment, the inner flow channel 1 and the guide vane 2 have a thickness of 30 mm and a width of 1200 mm, and are made of austenitic stainless steel S30403. The width of cut surface I is 15 mm; the width of cut surface II is 15 mm, and the angle between cut surface II and the generatrix of the curved surface of guide vane 2 is 45°. The thickness of panel 4, straight web 5, and arc-shaped web 6 is 40 mm.

[0060] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. For those skilled in the art, all features disclosed in the present invention, or all steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way without departing from the principles of the present invention. The present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A welding method for flow channels and guide vanes in the corner section of a large wind tunnel, characterized in that, The guide vane (2) is a semi-arc pipe; the inner flow channel (1) is a flat plate, and the two inner flow channels (1) are fixed at the front and rear ends of the guide vane (2) respectively; the curved surface of the contact between the inner flow channel (1) and the guide vane (2) is a bevel; the welding method includes the following steps: S1. Prepare the beveling; The bevels of the inner flow channel (1) and the guide vane (2) are prepared by milling machine; S2. Preliminary assembly of tooling (3); The tooling (3) is assembled on a steel platform in a symmetrical frame shape; the tooling (3) consists of 2 panels (4), 4 straight webs (5), and 2 curved webs (6); During the initial assembly, the two panels (4) are located on the upper and lower sides respectively, the two straight webs (5) are located at the front and rear ends respectively, and the two curved webs (6) are located in the middle. The curved webs (6) and the straight webs (5) are parallel to each other. The lower panel (4) is fixed to the steel platform by spot welding; S3. Assemble the inner flow channel (1) and the guide vane (2); Assemble the inner flow channel (1) and the guide plate (2) on the tooling (3); insert the guide plate (2) into the middle section of the tooling (3); insert the two inner flow channels (1) into the front and rear sections of the tooling (3) respectively; The lower surfaces of the edges of the two inner flow channels (1) and the guide vane (2) are respectively attached to the upper surfaces of the corresponding edges on the panel (4); the arc surface of the outer wall of the guide vane (2) is attached to the arc surface of the inner wall of the arc-shaped web (6); the bevels of the two inner flow channels (1) are respectively attached to the bevels of the corresponding guide vane (2). S4. Spot weld the inner flow channel (1) and the guide plate (2) to fix them. The inner flow channel (1) and the guide plate (2) are welded by tungsten inert gas welding, and the inner flow channel (1), the guide plate (2) and the tooling (3) are fixed by spot welding. S5. Supplementary assembly tooling (3); The remaining two straight web plates (5) are symmetrically installed between the arc-shaped web plate (6) and the straight web plate (5), placed at the weld position of the inner flow channel (1) and the guide plate (2), and spot welded to the contact surfaces of the panel (4), the guide plate (2), the inner flow channel (1), and the arc-shaped web plate (6); S6. The inner flow channel (1) and the guide plate (2) are welded on the cover. The inner flow channel (1) and the guide plate (2) are filled and covered by shielded metal arc welding. The tooling (3) is removed and the remaining welds at the positions blocked by the tooling (3) are completed.

2. The welding method for the flow channel and guide vanes in the corner section of a large wind tunnel according to claim 1, characterized in that, When preparing the bevel of the inner flow channel (1), the inner flow channel (1) is cut by a milling machine. The width of the cutting surface I is half the thickness t of the inner flow channel (1), and the cutting surface I is perpendicular to the bottom surface of the inner flow channel (1).

3. The welding method for the flow channel and guide vanes in the corner section of a large wind tunnel according to claim 1, characterized in that, When preparing the bevel of the guide plate (2), the guide plate (2) is cut by milling machine so that the width of the cut surface II is 15mm~25mm and the angle between the cut surface II and the generatrix of the curved surface of the guide plate (2) is 40°~50°.

4. The welding method for the flow channel and guide vanes in the corner section of a large wind tunnel according to claim 1, characterized in that, The thickness of the panel (4), straight web (5), and curved web (6) is greater than 30 mm.

Images