Welding method for hollow hemisphere, sphere welding method and welding tooling

Abstract

The present invention relates to the field of welding and processing of components, and discloses a hemispherical welding method, a spherical welding method and a welding tooling. The present invention converts all the conventional three-dimensional welding and processing of hollow hemispheres into one-dimensional processing. The welding head can achieve the welding of hemispheres and spheres through simple arc or circumferential movement. The adjustment of welding between different welds is also very simple and fast, which can greatly reduce the welding difficulty, improve the welding quality to a certain extent, effectively improve the welding efficiency, and can realize the welding from spherical segments to hemispheres and from hemispheres to spheres by using the same set of welding tooling. While ensuring the reliability and convenience of operation, the welding tooling is simplified and the processing cost is effectively reduced. The present invention is particularly suitable for the processing of large-diameter and thick-wall hemispheres or spheres with a diameter of more than 3m and a wall thickness of more than 50mm.

Description

Technical Field

[0001] The present invention relates to the field of welding processing of components, in particular to a welding method for a hollow hemisphere, a welding method for a sphere, and a welding tooling. Background Art

[0002] Large-diameter spheres or hemispheres are usually processed by a multi-part combination welding method. For example, the patent application with the publication number CN110145031A discloses a large-diameter thick steel structure hollow sphere and its manufacturing method. The hollow sphere in this patent application is formed by splicing two hemispherical shells, and each hemispherical shell is formed by splicing several spherical segments. The inside of the sphere has a skeleton support, and the spherical segments are all welded to the skeleton. This sphere structure and its manufacturing method are applicable to the processing and manufacturing of large-diameter spheres with a skeleton inside. For large-diameter spheres without a skeleton inside, reference can be made to the patent application with the publication number CN103934597A. This patent application discloses an auxiliary welding device for welding a hemispherical shell formed by splicing equally divided scraping bodies. By using this auxiliary welding device, the support of each part of the spherical segment and the flipping of the entire hemisphere can be realized, thereby improving the welding efficiency and welding quality. Combining the above technologies, it can be seen that the current processing method for hollow spheres is mainly to first process the top spherical segment and the circumferential spherical segments. The top spherical segment is a circular structure with a spherical arc, and the circumferential spherical segments are spherical segment structures divided along the meridian after removing the top spherical segment from the hemispherical surface. The hemisphere can be formed by combining and welding the top spherical segment and the circumferential spherical segments, and then the two hemispheres can be combined and welded into a sphere. For spheres with a skeleton inside, the skeleton can be used for support, and for spheres without a skeleton inside, an auxiliary welding device can be used for support welding.

[0003] At present, for the welding of large-diameter spheres, common welding techniques such as oxyacetylene welding and electric welding are generally used. However, these common welding methods are not very suitable for the welding of large-diameter spheres. The reasons are as follows: First, in conventional welding methods, the microstructure in the heat-affected zone changes greatly, and the residual stress is large, which is likely to cause deformation of the sphere, especially obvious for large-diameter spheres. Second, the weld length of large-diameter spheres is long, and it is difficult to complete a weld in one go with conventional welding methods, which is not conducive to mechanical automation. Third, for sphere structures made of materials such as aluminum alloy, conventional welding methods require additional shielding gas, resulting in higher costs and more complex processes. Given the great difficulty in applying conventional welding methods to the welding of large-diameter spheres, the applicant considers applying friction stir welding to the welding of large-diameter spheres. Friction stir welding uses the heat generated by the friction between a high-speed rotating welding tool and the workpiece to locally melt the welded material. When the welding tool moves forward along the welding interface, the plasticized material flows from the front of the welding tool to the back under the action of the rotational friction force of the welding tool and forms a dense solid-phase weld under the extrusion of the welding tool. Friction stir welding has the convenient advantages of small changes in the microstructure of the heat-affected zone, relatively low residual stress, the ability to complete a long weld in one go, and being convenient for realizing mechanical automation. Moreover, for aluminum alloy welding, no gas protection is required, which can better solve the problems of applying conventional welding methods to the welding of large-diameter spheres. However, applying friction stir welding to large-diameter spheres, especially hollow spheres, also has certain difficulties. In particular, friction stir welding has high requirements for the support rigidity of welding equipment and fixtures, and existing ordinary welding structures are difficult to meet the requirements.

[0004] The patent application with the publication number CN206795037U discloses a friction stir welding device. The device includes an assembly frame, a saddle, a telescopic column, a stir welding head, a bending drive mechanism, a linear drive mechanism and other structures. When the friction stir welding device works, first fix each spherical segment on the corresponding fixture in front of the vertical friction stir welding device, align the butt weld with the position where the stirring head is located. Then, control the drive component on the stirring head to make the stirring head rotate, and control the stirring head of the stirring head on the mixing machine head to penetrate into the specified depth inside the workpiece through the linear drive mechanism for friction stir welding. At the same time, control the saddle and the stirring head on the saddle to move along the arc guide rail through the bending drive mechanism to automatically complete a spherical segment butt weld from top to bottom. Using this device, the welding between spherical segments in the longitudinal direction can be better achieved by friction stir welding. However, there are still some problems. First, the device can only achieve the welding of circumferential spherical segments in the longitudinal direction, while the assembly of the sphere usually also includes the splicing of the top spherical segment and the hemispherical equator, and the device cannot achieve the welding in these directions. Second, after completing the welding of a butt joint between spherical segments, the device cannot simply perform the welding of the next weld, which will affect the welding efficiency to a certain extent. Third, the device is only applicable to the welding of the outside of the sphere. For spheres with a relatively large thickness, welding is also required inside to ensure the welding stability, which cannot be achieved by this improved device. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a welding method for a hollow hemisphere, a welding method for a sphere and a welding tooling, which can stably and controllably realize the welding between each spherical segment, and effectively improve the processing efficiency of the hemisphere or the sphere.

[0006] The welding method for a hollow hemisphere disclosed by the present invention includes the following steps:

[0007] Process the top spherical segment and the circumferential spherical segments of the hemisphere;

[0008] Assemble the top spherical segment and the circumferential spherical segments on the support of the welding tooling to form a hemisphere. The welding tooling includes an annular track distributed along the circumference of the hemisphere and an arc-shaped welding bearing beam. One end of the welding bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the top spherical segment of the hemisphere. The welding head is arranged on the welding bearing beam;

[0009] Adjust the position of the welding bearing beam along the annular track to align it with a splicing seam between two adjacent circumferential spherical segments. While the welding head is welding, it moves along the arc of the welding bearing beam to complete the welding of a splicing seam between two adjacent circumferential spherical segments. Adjust the welding bearing beam along the annular track to the splicing seams between other adjacent circumferential spherical segments to complete the welding between other adjacent circumferential spherical segments;

[0010] Adjust the welding head along the welding head to the splicing seam between the top spherical segment and the circumferential spherical segments. While the welding head is welding, the welding bearing beam moves circumferentially around the hemisphere along the annular track, and the welding head moves circumferentially with the welding bearing beam to complete the welding between the top spherical segment and the adjacent circumferential spherical segments.

[0011] Preferably, the welding method for the hollow hemisphere includes the welding of the outer weld seam and the inner weld seam of the hemisphere. The support includes an outer weld seam support and an inner weld seam support. The welding bearing beam includes an outer welding bearing beam and an inner welding bearing beam;

[0012] During the welding of the outer weld seam, place the hemisphere on the outer weld seam support of the welding tooling. The welding head is arranged on the outer welding bearing beam. One end of the outer welding bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the top spherical segment of the hemisphere. And the outer welding bearing beam is located outside the hemisphere. The welding head completes the welding of the outer weld seams between adjacent circumferential spherical segments and between the top spherical segment and the circumferential spherical segments on the outer welding bearing beam;

[0013] During the welding of the inner weld seam, place the hemispherical body on the inner weld seam support of the welding fixture. The welding head is arranged on the inner welding bearing beam. One end of the inner welding bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the top spherical segment of the hemispherical body. And the inner welding bearing beam is located inside the hemispherical body. The welding head completes the welding of the inner weld seam between adjacent circumferential spherical segments and between the top spherical segment and the circumferential spherical segments on the inner welding bearing beam.

[0014] Preferably, the friction stir welding process is used for welding the hemispherical body, and the welding head adopts a friction stir welding head.

[0015] The support body is provided with a welding support arc surface corresponding to the position of the weld seam, and the friction stir welding of the weld seam is realized through the surface support of the welding support arc surface.

[0016] Preferably, after welding is completed, replace the welding head on the welding bearing beam with a polishing device, and polish the weld seam according to the movement mode of the welding head.

[0017] Preferably, the friction stir welding process is used for welding the hemispherical body, and the welding head adopts a friction stir welding head.

[0018] During polishing, replace the stirring pin of the welding head with a milling cutter to polish the weld seam.

[0019] Preferably, when machining the top spherical segment, first divide it into two spherical arc-shaped spherical segment plates according to the shape of the top spherical segment, use square plates to machine two plate blanks containing the spherical segment plates, and then assemble and weld the two plate blanks to form an assembled plate blank containing the top spherical segment, and use the assembled plate blank for machining to form the top spherical segment.

[0020] The disclosed method for welding a hollow sphere of the present invention includes the following steps:

[0021] Use the above-mentioned method for welding a hollow hemispherical body to machine two hemispherical bodies.

[0022] On the welding fixture, assemble the two hemispherical bodies to form a sphere, and weld the splicing seam between the two hemispherical bodies.

[0023] Preferably, the above-mentioned method for welding a hollow hemispherical body includes the welding of the outer weld seam and the inner weld seam of the sphere. The welding bearing beam includes an outer welding bearing beam and an inner welding bearing beam, and the friction stir welding process is used for welding the sphere.

[0024] During the welding of the outer weld seam of the sphere, the outer welding bearing beam is arranged on the outside of the sphere, the inner welding bearing beam is correspondingly arranged on the inside of the sphere, the outer welding bearing beam is provided with a welding head, and the support of the inner side of the sphere by the inner welding bearing beam is used to weld the outer weld seam between the two hemispherical bodies.

[0025] When welding the internal weld of the sphere, the internal welding load-bearing beam is arranged inside the sphere, the external welding load-bearing beam is correspondingly arranged outside the sphere, and a welding head is arranged on the internal welding load-bearing beam. By using the support of the external welding load-bearing beam on the outside of the sphere, the internal weld between the two hemispheres is welded.

[0026] Preferably, when welding the weld between the two hemispheres,

[0027] Place the welding load-bearing beam provided with the welding head on the annular track arranged along the circumference of the sphere, and the welding load-bearing beam moves along the annular track to realize the welding of the sphere;

[0028] Or, support the welding load-bearing beam provided with the welding head through the support structure, and set it lying on its side corresponding to the splicing seam between the hemispheres. Clamping devices are symmetrically arranged on both sides of the welding load-bearing beam corresponding to the splicing seam between the hemispheres. The welding head moves in an arc along the welding load-bearing beam to complete the welding of one section of the sphere, and then adjust the welding load-bearing beam to complete the welding of the remaining sections of the sphere.

[0029] The welding tooling for a hollow sphere disclosed by the present invention includes a welding load-bearing beam and a welding head. The welding load-bearing beam is arc-shaped, and the welding head is arranged on the welding load-bearing beam. The welding tooling for the hollow sphere further includes an annular track and a support body, and the annular track is arranged circumferentially along the support body;

[0030] When used as a welding tooling for welding the spherical segments into a hemisphere, one end of the welding load-bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the support body;

[0031] When used as a welding tooling for welding the hemispheres into a sphere, one end of the welding load-bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the support body, or the welding load-bearing beam is arranged lying on its side on the annular track.

[0032] Preferably, the support body includes an external weld support body and an internal weld support body, the welding head is a friction stir welding head, and the welding load-bearing beam includes an external welding load-bearing beam and an internal welding load-bearing beam;

[0033] The outer side surface of the external weld support body forms a hemispherical shape, and the position of the outer side surface of the external weld support body corresponding to the circumferential weld between the spherical segments has an external welding support arc surface;

[0034] The inner side surface of the internal weld support body forms a hemispherical shape, and the position of the inner side surface of the internal weld support body corresponding to the circumferential weld between the spherical segments has an internal welding support arc surface;

[0035] The annular track is arranged at the top of the inner weld support body, and the top of the inner weld support body has an annular support surface adapted to the outer weld support body inside the annular track;

[0036] When welding the outer weld, the outer weld support body is arranged on the annular support surface of the inner weld support body, one end of the outer welding bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the outer weld support body;

[0037] When welding the inner weld, one end of the inner welding bearing beam is arranged on the annular track, and the other end is rotatably arranged at the center of the inner weld support body.

[0038] In the present invention, the conventional three-dimensional welding process of a hollow hemisphere is completely converted into a one-dimensional process. The welding head can realize the welding of the hemisphere and the sphere through simple arc or circumferential movement. The adjustment between different welds is also very simple and fast, which can greatly reduce the welding difficulty, improve the welding quality to a certain extent, effectively improve the welding efficiency, and can realize the welding from the spherical segment to the hemisphere and from the hemisphere to the sphere by using the same set of welding tooling. While ensuring the reliability and convenience of operation, the welding tooling is simplified, and the processing cost is effectively reduced. The present invention is particularly suitable for the processing of large-diameter and thick-wall hemispheres or spheres with a diameter of more than 3m and a wall thickness of more than 50mm. Description of the Drawings

[0039] Figure 1 is a processing schematic diagram of the top spherical segment;

[0040] Figure 2 is an assembly schematic diagram of the hemisphere;

[0041] Figure 3 is a schematic diagram of the outer weld support body;

[0042] Figure 4 is a schematic diagram of the outer weld welding of the hemisphere;

[0043] Figure 5 is a schematic diagram of the inner weld support body;

[0044] Figure 6 is a schematic diagram of the inner weld welding of the hemisphere;

[0045] Figure 7 is a schematic diagram of the sphere welding;

[0046] Figure 8 is a cross-sectional view of the sphere welding.

[0047] Reference numerals: top spherical segment 1, circumferential spherical segment 2, external weld support 3, external welding support arc surface 4, rotating shaft 5, external welding bearing beam 6, welding head 7, annular track 8, internal welding bearing beam 9, internal weld support 10, internal welding support arc surface 11, sheet blank 12, hemispherical body 13, clamping device 14, spherical body 15, platform foundation 16. Detailed implementation mode

[0048] The present invention will be further described below.

[0049] As described in the background art, the welding process of a hollow spherical body usually involves welding spherical segments into a hemispherical body 13, and then assembling and welding the hemispherical bodies 13 into a spherical body 15. Therefore, to machine a hollow spherical body, it is first necessary to machine a hollow hemispherical body. At the same time, the hollow hemispherical body itself also has industrial applications. The welding method for a hollow hemispherical body of the present invention includes the following steps:

[0050] Machine the top spherical segment 1 and the circumferential spherical segment 2 of the hemispherical body 13;

[0051] Assemble the top spherical segment 1 and the circumferential spherical segment 2 on the support of the welding fixture to form a hemispherical body 13. The welding fixture includes an annular track 8 distributed circumferentially along the hemispherical body 13 and an arc-shaped welding bearing beam. One end of the welding bearing beam is arranged on the annular track 8, and the other end is rotatably arranged at the center of the top spherical segment 1 of the hemispherical body 13. The welding head 7 is arranged on the welding bearing beam;

[0052] Adjust the position of the welding bearing beam along the annular track 8 to align it with a splicing seam between two adjacent circumferential spherical segments 2. While the welding head 7 is welding, it moves along the arc of the welding bearing beam to complete the welding of a splicing seam between two adjacent circumferential spherical segments 2. Adjust the welding bearing beam along the annular track 8 to the splicing seams between other adjacent circumferential spherical segments 2 to complete the welding between other adjacent circumferential spherical segments 2;

[0053] Adjust the welding head 7 along the welding bearing beam to the splicing seam between the top spherical segment 1 and the circumferential spherical segment 2. While the welding head 7 is welding, the welding bearing beam moves circumferentially around the hemispherical body 13 along the annular track 8, and the welding head 7 moves circumferentially with the welding bearing beam to complete the welding between the top spherical segment 1 and the adjacent circumferential spherical segment 2.

[0054] The structures of the circumferential spherical valve 2 and the top spherical valve 1 can refer to existing processing methods, which can usually be formed by using a plate bending device in cooperation with machining. The circumferential spherical valve 2 is relatively wide in width and relatively long in length, and is usually easy to bend. For the top spherical valve 1 with a small diameter, it is also relatively easy to directly process. However, if the diameter of the top spherical valve 1 is large, it is difficult to directly form a standard spherical arc. For example, in the sphere 15 processed in the embodiment of the present invention, a flange hole with a diameter of about 2 m needs to be opened in the top spherical valve 1. Considering the stability of the top spherical valve 1 and at the same time dispersing the weld cross-section to a greater extent, the diameter of the top spherical valve 1 is more than 5 m. It is very difficult to directly process and form such a huge top spherical valve 1. In this regard, as Figure 1 shown, as a preferred embodiment, when processing the top spherical valve 1, first divide it into two spherical arc-shaped valve plate blanks according to the shape of the top spherical valve 1, use a square plate to process two plate blanks 12 including the valve plate blanks, and then group and weld the two plate blanks 12 to form a grouped plate blank including the top spherical valve 1, and use the grouped plate blank to machine the top spherical valve 1. It is much easier to bend and process the plate blank 12 with a spherical arc. First group and weld the plate blanks 12 to form a grouped plate blank, and then machine the shape of the top spherical valve 1. Compared with machining the shape first and then bending and welding, the forming accuracy can be better guaranteed. Because the diameter of the top spherical valve 1 is large, its group welding can also be completed on the welding fixture for subsequent hemisphere processing.

[0055] As Figure 2 shown, after the top spherical valve 1 and the circumferential spherical valve 2 are processed, they can be grouped to form a hemisphere 13, and then welding is required, which needs to be carried out with the help of a welding fixture. The welding fixture includes a support body for supporting the sphere 15, a welding carrier beam for carrying the welding head 7, and an annular track 8 for the circumferential movement of the welding carrier beam. A more perfect welding fixture will be described later. The hemisphere 13 is arranged on the support body, and the annular track 8 is arranged around its circumference. Specifically, it can be arranged on the outer circumference of the hemisphere 13 or on the inner circumference of the hemisphere 13. Considering the convenience of arrangement, the former is usually preferred. One end of the welding carrier beam and the annular track 8 can adopt a common rolling or sliding track matching method, and a rotating shaft 5 can be arranged at the center of the top spherical valve 1 to cooperate with the other end of the welding carrier beam. For example, Figure 4As shown, the top spherical segment 1 with a flange hole in the center can be provided with a rotating shaft 5 and a rotating hole on the support body, and the structure is matched with the welding bearing beam. By means of this welding tooling, the welding head 7 moves along the arc of the welding bearing beam, and the welding between adjacent circumferential spherical segments 2 can be realized. Although the welding head 7 itself moves in an arc, the welding head 7 can be regarded as a one-dimensional movement relative to the spherical surface, which is equivalent to the movement track of the butt weld on the flat plate. The position of the welding bearing beam can be adjusted through the annular track 8 to quickly complete the welding between all circumferential spherical segments 2. For the welding between the circumferential spherical segment 2 and the top spherical segment 1, the welding head 7 can also be positioned at the weld, and the welding bearing beam can be run around the annular track 8 to complete it. In this way, only through the relative movement between the welding head 7 and the welding bearing beam and the relative movement between the welding bearing beam and the annular track 8, the welding of all welds of the hemisphere 13 can be realized. Before the formal welding of the weld, the weld can be spot-welded in advance according to the conventional welding of large-size components. After the spot welding is completed, the overall dimension accuracy can be detected first, and a full-range balanced clamping before the weld welding can be done to ensure the stable progress of the subsequent welding. It should be noted that it is feasible to weld between the circumferential spherical segments 2 first or between the circumferential spherical segment 2 and the top spherical segment 1 first. In view of the fact that the support body adopted in the embodiment does not provide a complete circumferential support surface at the weld between the circumferential spherical segment 2 and the top, therefore, the method of welding between the circumferential spherical segments 2 first and then between the circumferential spherical segment 2 and the top spherical segment 1 is adopted.

[0056] For a spherical body 15 or a hemisphere 13 structure with a relatively large wall thickness, it is difficult to penetrate the weld by single-sided welding and the bonding strength cannot be guaranteed. Therefore, double-sided welding is required. The preferred embodiment of the present invention adopts a double-sided welding method, which specifically includes the external weld welding and the internal weld welding of the hemisphere 13. The support body includes an external weld support body 3 and an internal weld support body 10, and the welding bearing beam includes an external welding bearing beam 6 and an internal welding bearing beam 9;

[0057] As Figure 4 shown, during the external weld welding, the hemisphere 13 is placed on the external weld support body 3 of the welding tooling. The welding head 7 is arranged on the external welding bearing beam 6. One end of the external welding bearing beam 6 is arranged on the annular track 8, and the other end is rotatably arranged at the center of the top spherical segment 1 of the hemisphere 13. And the external welding bearing beam 6 is located outside the hemisphere 13. The welding head 7 completes the external weld welding between adjacent circumferential spherical segments 2 and between the top spherical segment 1 and the circumferential spherical segment 2 on the external welding bearing beam 6;

[0058] As Figure 6As shown, when welding the inner weld, the hemisphere 13 is placed on the inner weld support 10 of the welding tool, and the welding head 7 is set on the inner welding load-bearing beam 9. One end of the inner welding load-bearing beam 9 is set on the annular track 8, and the other end is rotatably set at the center of the top ball petal 1 of the hemisphere 13, and the inner welding load-bearing beam 9 is located on the inner side of the hemisphere 13. The welding head 7 completes the inner weld welding between adjacent circumferential ball petals 2 and between the top ball petal 1 and the circumferential ball petal 2 on the inner welding load-bearing beam 9.

[0059] The support body is usually supported below the sphere 15, and the welding also needs to avoid overhead welding as much as possible. Figure 3 As shown, the outer weld support body 3 generally adopts an inverted hemispherical structure, such as Figure 5 As shown, the inner weld support 10 generally adopts a hemispherical structure with the opening facing upwards. In the welding of the inner and outer welds, the operation mode of the welding head 7 is the same, and the welding of the inner and outer welds is realized respectively. In the embodiment of the present invention, the wall thickness of the sphere reaches about 130 mm, and the single-sided welding only needs to ensure that it can reach more than 70 mm.

[0060] As described in the background technology, friction stir welding has its own unique advantages over ordinary welding methods, and is particularly applicable to the sphere 15 or hemisphere 13 made of aluminum alloy. Therefore, in the embodiment of the present invention, the hemisphere 13 is welded by the friction stir welding process, and the welding head 7 adopts the friction stir welding head 7; however, since friction stir welding requires more stable support, the support body is provided with a welding support arc surface at the position corresponding to the weld, and the friction stir welding of the weld is achieved by the surface support of the welding support arc surface.

[0061] After welding, most spheres 15 or hemispheres 13 need to polish the weld. For welds that need to be polished, after welding, the welding head 7 on the welding load beam is replaced with a polishing device, and the weld is polished according to the movement of the welding head 7. That is, the same set of tooling is used for welding and polishing, and only the welding head 7 and the polishing device need to be replaced. For the welding of the hemisphere 13 using the stir friction welding process, the welding head 7 uses the stir friction welding head 7; during polishing, because the milling cutter and the stirring needle of the welding head 7 are both rotating, it is only necessary to replace the stirring needle of the welding head 7 with a milling cutter to polish the weld, which can greatly simplify the operation and reduce the equipment cost. If welding is performed on both the inside and outside, it is preferred to polish the weld on one side after the weld is completed, and then weld and polish the weld on the other side. For example, the outer weld is welded first, and then the outer weld is polished after completion, and then the inner weld is welded, and finally the inner weld is polished, which is more convenient in operation.

[0062] Based on the welded hemispheres 13, the welding of the hollow hemisphere can be carried out. Specifically, two hemispheres 13 are processed by the above-mentioned hemisphere welding method. On the welding fixture, the two hemispheres 13 are assembled to form a sphere 15, and the splicing seam between the two hemispheres 13 is welded. The welding of the sphere 15 uses the same welding fixture as that of the hemisphere 13. Especially for ordinary welding methods such as electric welding and oxygen welding, the welding bearing beam can directly adopt the layout method of the previous hemisphere welding, that is, one end of the welding bearing beam is arranged on the annular track 8, and the other end is rotatably arranged at the center of the top petal 1 of the hemisphere 13. Referring to the welding between the top petal 1 and the circumferential petal 2, the welding bearing beam provided with the welding head 7 is placed on the annular track 8 arranged along the circumference of the sphere 15, and the welding bearing beam moves along the annular track 8 to realize the welding of the sphere 15.

[0063] For friction stir welding, during the welding process of the sphere 15, it is difficult for the support body to provide support at the equatorial position anymore. And additionally setting corresponding support structures will undoubtedly increase the complexity of the structure. This problem has been well solved in the preferred embodiment of the present invention. Refer to Figure 7 and 8 , the welding of the hollow hemisphere includes the welding of the outer weld seam and the inner weld seam of the sphere 15. The welding bearing beam includes an outer welding bearing beam 6 and an inner welding bearing beam 9. The friction stir welding process is used to weld the sphere 15;

[0064] When welding the outer weld seam of the sphere 15, the outer welding bearing beam 6 is arranged on the outside of the sphere 15, the inner welding bearing beam 9 is correspondingly arranged on the inside of the sphere 15, and the outer welding bearing beam 6 is provided with a welding head 7. Utilizing the support of the inner welding bearing beam 9 on the inside of the sphere 15, the outer weld seam between the two hemispheres 13 is welded;

[0065] When welding the inner weld seam of the sphere 15, the inner welding bearing beam 9 is arranged on the inside of the sphere 15, the outer welding bearing beam 6 is correspondingly arranged on the outside of the sphere 15, and the inner welding bearing beam 9 is provided with a welding head 7. Utilizing the support of the outer welding bearing beam 6 on the outside of the sphere 15, the inner weld seam between the two hemispheres 13 is welded.

[0066] That is, when welding the outer weld seam, the outer welding bearing beam 6 is used as the carrier of the welding head 7, and the inner welding bearing beam 9 provides the inner support. When welding the inner weld seam, the inner welding bearing beam 9 is used as the carrier of the welding head 7, and the outer welding bearing beam 6 provides the outer support. Of course, in view of the fact that the surfaces of the inner and outer welding bearing beams 6 do not completely fit the surface of the sphere 15, therefore, it is best to add a support clamping device 14 on the basis of the welding bearing beam for better support and at the same time provide a certain clamping effect.

[0067] As mentioned above, the welding of the equatorial seam of the sphere 15 is realized by the movement of the welding carrier beam provided with the welding head 7 along the circular track 8. This is more suitable for conventional welding methods. If the friction stir welding process is adopted, while providing support on the opposite side, it is best to clamp the weld seam to ensure the welding quality. In this welding method, if a clamping device 14 is to be set, corresponding tooling components need to be configured additionally. In order to make the best use of the existing tooling components, such as Figure 7 and 8 shown, when welding the weld seam between the two hemispheres 13, the welding carrier beam provided with the welding head 7 is supported by the support structure and is arranged laterally corresponding to the splicing seam between the hemispheres 13. Clamping devices 14 are symmetrically arranged on both sides of the welding carrier beam corresponding to the splicing seam between the hemispheres 13. The welding head 7 moves along the arc of the welding carrier beam to complete the welding of a section of the sphere equatorial seam, and then the welding carrier beam is adjusted to complete the welding of the remaining sections of the sphere. For the welding of the internal and external weld seams using the friction stir welding process, clamping devices 14 can be respectively arranged on the outer welding carrier beam 6 and the inner welding carrier beam 9. The clamping device 14 can provide the functions of support and clamping. The clamping device 14 is preferably an existing clamping head with adjustable clamping force, and the clamping force of each clamping head is adjusted respectively to ensure the fitting degree and effectiveness of the clamping. After the clamping is stable, the welding head 7 moves along the arc of the welding carrier beam to realize the welding of a section of the equatorial seam. After the internal and external weld seams of this section are completed, the positions of the outer welding carrier beam 6 and the inner welding carrier beam 9 can be adjusted to perform the welding of the next section until the entire circular weld seam is completed. The support structure is used to support the welding carrier beam. Usually, the circular track 8 is arranged on the outer periphery of the sphere 15 and can directly serve as the support structure of the outer welding carrier beam 6. Inside the sphere 15, an additional support structure needs to be set or the structure of the sphere 15 itself is used to support the inner welding carrier beam 9. Such as Figure 7 and 8 shown in the embodiment, since there is a flange at each 90° position on the equator of the spherical shell, the flange naturally divides the equatorial weld seam into 4 sections, and the length of each section of the equatorial weld seam is less than 1 / 4 of the circumference. The lateral arrangement of the outer welding carrier beam 6 and the inner welding carrier beam 9 can meet the length requirements of a section of the equatorial weld seam. The tooling inside the sphere 15 can be disassembled and removed from the sphere 15 through the flange holes of the ball head. However, it is still best to place components such as the inner weld carrier beam inside the spherical shell before the assembly of the spherical shell.

[0068] Based on the above processing methods for the hemisphere and the sphere, the present invention hereby provides a preferred welding tooling for a hollow sphere, which includes a welding bearing beam and a welding head 7. The welding bearing beam is arc-shaped, and the welding head 7 is arranged on the welding bearing beam. This welding tooling further includes an annular track 8 and a support body. The annular track 8 is arranged circumferentially along the support body. When used as a welding tooling for welding the spherical segments into a hemisphere 13, one end of the welding bearing beam is arranged on the annular track 8, and the other end is rotatably arranged at the center of the support body. When used as a welding tooling for welding the hemisphere 13 into a sphere, one end of the welding bearing beam is arranged on the annular track 8, and the other end is rotatably arranged at the center of the support body, or the welding bearing beam is laterally arranged on the annular track 8. Referring to the foregoing, during the welding of the hemisphere 13, the welding head 7 is aligned with the weld seam, and the welding head 7 moving along the arc-shaped welding bearing beam can achieve the welding between the circumferential spherical segments 2. The welding bearing beam moving along the annular track 8 can achieve the welding between the circumferential spherical segments 2 and the top spherical segment 1. During the welding of the sphere 15, the welding head 7 is aligned with the equatorial weld seam. The welding bearing beam moving along the annular track 8 can achieve the welding between the two hemispheres 13. The welding bearing beam being laterally arranged on the annular track 8 can also achieve the welding of a section of the equatorial seam. By further adjusting the position of the welding bearing beam, the circumferential welding of the entire equatorial seam can be completed.

[0069] For friction stir welding, the welding head 7 is a friction stir welding head 7; the welding tooling must lay a platform foundation 16, and build a welding tooling support on the platform foundation 16 to bear the upsetting force and thrust required for welding. Welding is to be performed on both the inner and outer sides of the sphere 15. Then, the support body includes an outer weld support body 3 and an inner weld support body 10, which are respectively used to support the inner and outer surfaces of the sphere 15. In view of the fact that the friction stir welding process is adopted, therefore, the outer side surface of the outer weld support body 3 forms a hemispherical shape, and the position of the outer side surface of the outer weld support body 3 corresponding to the weld between the circumferential spherical segments 2 has an outer welding support arc surface 4, which supports the inner side of the weld between the circumferential spherical segments 2 during outer weld welding. The inner side surface of the inner weld support body 10 forms a hemispherical shape, and the position of the inner side surface of the inner weld support body 10 corresponding to the weld between the circumferential spherical segments 2 has an inner welding support arc surface 11, which supports the outer side of the weld between the circumferential spherical segments 2 during inner weld welding. In order to minimize the component adjustment during the welding process of the sphere 15 and the tooling, the annular track 8 is arranged on the top of the inner weld support body 10, and the top of the inner weld support body 10 has an annular support surface adapted to the outer weld support body 3 inside the annular track 8. In this tooling, the inner weld support body 10 simultaneously serves as a base to support the annular track 8 and the outer weld support body 3. During outer weld welding, the outer weld support body 3 is arranged on the annular support surface of the inner weld support body 10, and one end of the outer welding load-bearing beam 6 is arranged on the annular track 8, and the other end is rotatably arranged at the center of the outer weld support body 3; during inner weld welding, one end of the inner welding load-bearing beam 9 is arranged on the annular track 8, and the other end is rotatably arranged at the center of the inner weld support body 10. During the entire welding process of the sphere 15, for the welding tooling, only the outer weld support body 3, the outer welding load-bearing beam 6, and the inner welding load-bearing beam 9 need to be adjusted, and the inner weld support body 10 and the annular track 8 remain unchanged. During the welding of the sphere 15, it is only necessary to keep the lower hemisphere inside the inner weld support body 10 and place the upper hemisphere on top of the lower hemisphere to perform butt welding.

Claims

1. Welding method for a hollow hemisphere, characterized in that, It includes the following steps: Process the top spherical segment (1) and circumferential spherical segments (2) of the hemispherical body (13); Assemble and pair the top spherical segment (1) and circumferential spherical segments (2) on the support body of the welding fixture to form the hemispherical body (13). The welding fixture includes an annular track (8) distributed along the circumference of the hemispherical body (13) and an arc-shaped welding bearing beam. One end of the welding bearing beam is arranged on the annular track (8), and the other end is rotatably arranged at the center of the top spherical segment (1) of the hemispherical body (13). The welding head (7) is arranged on the welding bearing beam; Adjust the position of the welding bearing beam along the annular track (8) to align it with a splicing seam between adjacent circumferential spherical segments (2). While the welding head (7) is welding, it moves along the arc of the welding bearing beam to complete the welding of the splicing seam between adjacent circumferential spherical segments (2). Adjust the welding bearing beam along the annular track (8) to the splicing seams between other adjacent circumferential spherical segments (2) to complete the welding between other adjacent circumferential spherical segments (2); Adjust the welding head (7) along the welding bearing beam to the splicing seam between the top spherical segment (1) and the circumferential spherical segments (2). While the welding head (7) is welding, the welding bearing beam moves circumferentially around the hemispherical body (13) along the annular track (8), and the welding head (7) makes a circumferential movement along with the welding bearing beam to complete the welding between the top spherical segment (1) and the adjacent circumferential spherical segments (2).

2. The welding method for a hollow hemisphere according to claim 1, characterized in that: It includes the welding of the outer weld seam and the inner weld seam of the hemispherical body (13). The support body includes an outer weld seam support body (3) and an inner weld seam support body (10). The welding bearing beam includes an outer welding bearing beam (6) and an inner welding bearing beam (9); During the outer weld seam welding, place the hemispherical body (13) on the outer weld seam support body (3) of the welding fixture. The welding head (7) is arranged on the outer welding bearing beam (6). One end of the outer welding bearing beam (6) is arranged on the annular track (8), and the other end is rotatably arranged at the center of the top spherical segment (1) of the hemispherical body (13). And the outer welding bearing beam (6) is located outside the hemispherical body (13). The welding head (7) completes the welding of the outer weld seams between adjacent circumferential spherical segments (2) and between the top spherical segment (1) and the circumferential spherical segments (2) on the outer welding bearing beam (6); During the inner weld seam welding, place the hemispherical body (13) on the inner weld seam support body (10) of the welding fixture. The welding head (7) is arranged on the inner welding bearing beam (9). One end of the inner welding bearing beam (9) is arranged on the annular track (8), and the other end is rotatably arranged at the center of the top spherical segment (1) of the hemispherical body (13). And the inner welding bearing beam (9) is located inside the hemispherical body (13). The welding head (7) completes the welding of the inner weld seams between adjacent circumferential spherical segments (2) and between the top spherical segment (1) and the circumferential spherical segments (2) on the inner welding bearing beam (9).

3. The welding method for a hollow hemisphere according to claim 1 or 2, characterized in that: Use the friction stir welding process to weld the hemispherical body (13). The welding head (7) uses a friction stir welding head (7); The support body is provided with a welding support arc surface at the position corresponding to the weld seam, and the friction stir welding of the weld seam is realized through the surface support of the welding support arc surface.

4. The welding method for a hollow hemisphere according to claim 1 or 2, characterized in that: After welding is completed, replace the welding head (7) on the welding support beam with a polishing device, and polish the weld seam according to the movement mode of the welding head (7).

5. The welding method for a hollow hemisphere according to claim 4, characterized in that: Use friction stir welding process to weld the hemispheres (13), and the welding head (7) is a friction stir welding head (7). When polishing, replace the stirring pin of the welding head (7) with a milling cutter to polish the weld seam.

6. The welding method for a hollow hemisphere according to claim 1, characterized in that: When processing the top spherical segment (1), first divide it into two spherical arc-shaped segment plates according to the shape of the top spherical segment (1), use square plates to process two initial segment blanks (12) containing the segment plates, then assemble and weld the two initial segment blanks (12) to form an assembled segment blank containing the top spherical segment (1), and use the assembled segment blank for machining to form the top spherical segment (1).

7. Welding method for a hollow sphere, characterized in that, The method includes the following steps: Use the hollow hemisphere welding method according to any one of claims 1-6 to process two hemispheres (13). On the welding fixture, assemble the two hemispheres (13) to form a sphere, and weld the splicing seam between the two hemispheres (13).

8. The welding method for a hollow sphere according to claim 7, characterized in that: It includes the welding of the outer weld seam and the inner weld seam of the sphere. The welding support beam includes an outer welding support beam (6) and an inner welding support beam (9), and use friction stir welding process to weld the sphere. When welding the outer weld seam of the sphere, the outer welding support beam (6) is arranged on the outside of the sphere, the inner welding support beam (9) is correspondingly arranged on the inside of the sphere, the outer welding support beam (6) is provided with a welding head (7), and use the support of the inner welding support beam (9) on the inside of the sphere to weld the outer weld seam between the two hemispheres (13). When welding the inner weld seam of the sphere, the inner welding support beam (9) is arranged on the inside of the sphere, the outer welding support beam (6) is correspondingly arranged on the outside of the sphere, the inner welding support beam (9) is provided with a welding head (7), and use the support of the outer welding support beam (6) on the outside of the sphere to weld the inner weld seam between the two hemispheres (13).

9. The welding method for a hollow sphere according to claim 7 or 8, characterized in that: When welding the weld seam between the two hemispheres (13), Place the welding support beam provided with the welding head (7) on the annular track (8) arranged along the circumference of the sphere, and the welding support beam moves along the annular track (8) to realize the welding of the sphere. Alternatively, support the welding support beam provided with the welding head (7) through the support structure, and place it lying on its side corresponding to the splicing seam between the hemispheres (13). Symmetrically arrange clamping devices (14) on both sides of the welding support beam corresponding to the splicing seam between the hemispheres (13). The welding head (7) moves along the arc of the welding support beam to complete the welding of a section of the sphere, and adjust the welding support beam to complete the welding of the remaining sections of the sphere.

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