Grid structure for suspension bridge and forming method thereof

Abstract

The invention relates to the technical field of cable saddle supporting structures of suspension bridges, and particularly discloses a grid structure for a suspension bridge and a forming method of the grid structure. The grid structure is provided with a bottom plate, a top plate, a plurality of longitudinal rib plates and a plurality of transverse rib plates, the longitudinal rib plates and the transverse rib plates are vertically arranged between the bottom plate and the top plate, and a pouring cavity is defined by the adjacent longitudinal rib plates and the adjacent transverse rib plates between the bottom plate and the top plate. The longitudinal rib plates defining the pouring cavity form continuous welding seams with the bottom plate, the top plate and the transverse rib plates respectively, and the transverse rib plates form continuous welding seams with the bottom plate and the top plate respectively. On the premise that the structure is not greatly changed, an over-welding hole structure in the pouring cavity is removed, so that a non-interrupted continuous welding seam is formed in the pouring cavity, and the method can be effectively suitable for automatic welding operation of a welding robot.

Description

Technical Field

[0001] The invention relates to a cable saddle supporting structure of a suspension bridge, in particular to a grid structure for a suspension bridge and a forming method of the grid structure. Background Art

[0002] In the suspension bridge structure, the saddles (including main saddles, loose saddles, steering saddles, etc.) installed on the tower base (referring to the installation foundation including the main tower or piers, etc., the same below) are important structural parts for supporting and steering the main cables. The installation of the saddle on the tower base is achieved through the mounting seat on the tower base. The mounting seat on the tower base is mainly composed of a grid structure embedded in the tower base and a support plate on the grid structure.

[0003] The grid structure used for cable saddle installation is a box-shaped steel frame composed of a top steel plate (i.e., top plate), a bottom steel plate (i.e., bottom plate), a number of longitudinal steel plates (i.e., longitudinal ribs) and a number of transverse steel plates (i.e., transverse ribs) welded together to form an integral structure. It has a number of regularly distributed casting cavities that can be respectively inserted with embedded steel bars and grouted. It is anchored to the tower base through the concrete grouted in each casting cavity and a number of embedded steel bars inserted at the bottom steel plate. It is a permanent structure in the suspension bridge. It can be seen that the grid structure plays a key role in force bearing and force transmission in the suspension bridge structure system, and its forming structure is directly related to the safety and durability of the suspension bridge structure system.

[0004] For a long time, the welding and forming between the top plate, bottom plate, several longitudinal ribs and several transverse ribs that make up the grid structure has been realized by manual welding. In order to adapt to the development of manual welding operations and avoid repeated welding heat effects, a through-welding hole is opened at the flat joint of the bottom plate and the top plate (that is, the contour edge of the longitudinal ribs and the transverse ribs corresponding to the joint of the bottom plate and the top plate). Due to the integrity of the longitudinal ribs in the longitudinal direction and the segmentation of the transverse ribs in the transverse direction, the through-welding hole is usually formed on the transverse ribs that surround the casting cavity, that is, the joints at the bottom and top of the casting cavity are respectively discontinuous and disconnected at the corresponding through-welding hole. For a grid with such a structure, when manually welding the joint at the bottom / top of the casting cavity, the through-welding hole at the current flat joint is used as the starting point and end point of the current fillet weld.

[0005] The manual welding operation of the grid structure has technical problems such as high labor intensity, low operation efficiency, poor weld quality consistency, and high cost. This is particularly prominent in the large-structure grid used in the long-span suspension bridge. The large-structure grid used in the long-span suspension bridge has a length of more than ten meters or even more than twenty meters in the longitudinal direction of the bridge, and a width of more than five meters in the transverse direction of the bridge. The number of casting cavities formed is large, and the number of welds is more (a casting cavity has four flat joints at the bottom, four flat joints at the top, and four vertical joints, a total of twelve joints need to be welded), and the welding workload is huge. In order to improve operation efficiency, reduce manufacturing costs, and ensure the consistency of weld quality, it is imperative to use the rapidly developing welding robots to perform automated welding operations on grid structures.

[0006] However, as mentioned above, the current design structure of the grid is designed to meet the manual welding operation mode. There is a through-welding hole structure in each casting cavity that hinders the continuous welding of the welding robot. In order to promote the automated welding operation of the welding robot on the grid structure, it is necessary to make targeted adjustments to the design structure of the grid. Summary of the invention

[0007] The technical purpose of the present invention is to provide a grating structure for a suspension bridge suitable for automated welding by a welding robot, and a forming method of the grating structure based on automated welding by a welding robot, in view of the particularity of the grating structure for the suspension bridge and the deficiencies of the prior art.

[0008] The technical purpose of the present invention is achieved by the following technical solution: a grid structure for a suspension bridge, comprising a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs; A plurality of longitudinal ribs are arranged between the bottom plate and the top plate along the transverse bridge direction, and each longitudinal rib is arranged vertically along the bridge direction; The plurality of transverse ribs are divided into a plurality of groups, and the plurality of transverse ribs in each group are arranged along the longitudinal spacing in each longitudinal channel between the bottom plate and the top plate, and each transverse rib is arranged vertically in the transverse direction of the bridge; Adjacent longitudinal ribs and adjacent transverse ribs between the bottom plate and the top plate form a casting cavity, the bottom plate has a bottom casting port connected to each casting cavity and having a smaller outline than the corresponding casting cavity, and the top plate has a top casting port connected to each casting cavity and having a smaller outline than the corresponding casting cavity; The longitudinal ribs that enclose the casting cavity respectively form continuous welds with the bottom plate, the top plate and the transverse ribs, and the transverse ribs respectively form continuous welds with the bottom plate and the top plate.

[0009] The above technical measures are aimed at the particularity of the grating structure for the suspension bridge. Without making major structural changes, the through-welding hole structure in the casting cavity is removed to form a non-interrupted continuous weld in the casting cavity, which can effectively adapt to the automated welding operation of the welding robot. Moreover, compared with the grating structure with through-welding holes, the molding structure of the above technical measures is simpler, easy to quickly cut materials, and conducive to improving work efficiency.

[0010] As one of the preferred technical solutions, the top side pouring port contour structure on the top plate is equal to the bottom side pouring port contour structure on the bottom plate.

[0011] Furthermore, the top side pouring opening on the top plate has a width of 280 to 505 mm along the direction of the adjacent longitudinal ribs; The length of the top side pouring port on the top plate along the direction of the adjacent transverse ribs is 265 to 305 mm.

[0012] Furthermore, the bottom side pouring opening on the bottom plate has a width of 280 to 505 mm along the direction of the adjacent longitudinal ribs; The length of the bottom pouring opening on the bottom plate along the direction of the adjacent transverse ribs is 265 to 305 mm.

[0013] Furthermore, the width of the casting cavity along the direction of adjacent longitudinal ribs is 490 to 645 mm; The casting cavity has a length of 395 to 420 mm along the direction of adjacent transverse ribs; The height of the casting cavity along the direction of the bottom plate and the top plate is 420-450 mm.

[0014] The above technical measures will not damage the overall structural rigidity of the grid structure while meeting the requirement of grouting and anchoring of the embedded steel bars, thereby ensuring that the grid structure has good bearing performance.

[0015] A method for forming the grating structure for a suspension bridge, the method comprising the following process steps: Step 1. According to the design structure, establish a theoretical 3D model that can be imported into the welding robot; The steel plate is cut and blanked to obtain a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs; Step 2. Arrange a plurality of longitudinal ribs and a plurality of transverse ribs vertically and horizontally on the bottom plate in an upright manner according to the designed structure, and assemble them by spot welding; Secure the assembled structure to the work platform; Step 3. Import the theoretical 3D model into the welding robot; Step 4. The welding robot performs a global visual scan of the assembled structure through a global visual system to obtain a scanned 3D cloud image, and globally matches the 3D cloud image with the theoretical 3D model. After the matching is completed, a welding task is generated according to the set welding sequence; When the welding robot automatically welds the joint seams in each casting cavity, the robot arm extends into the current casting cavity from the open area surrounded by the transverse ribs and the longitudinal ribs, and first welds the four vertical joint seams between the transverse ribs and the longitudinal ribs in sequence to form fillet welds; then continuously welds the four flat joint seams at the bottom plate in a continuous arc manner to form fillet welds; Step 5. According to the designed structure, spot weld the top plate onto each longitudinal rib and each transverse rib; Step 6. Turn the relative positions of the bottom plate and the top plate on the work platform so that the top plate is facing downward and the bottom plate is facing upward; Fix the turned structure on the working platform; Step 7. Repeat step 4; When the welding robot automatically welds the joint seams in each casting cavity, the robot arm extends from the casting port on the bottom side of the bottom plate into the current casting cavity, and continuously welds the four flat joint seams at the top plate in the current casting cavity in a continuous arc manner to complete the automatic welding; Step 8. Perform quality inspection on the welded grid; Step 9. The grilles that have passed the quality inspection will be transferred to the heat treatment process and the finishing process in sequence until they are finished products.

[0016] Furthermore, there are two welding robots arranged at the working platform, and the two welding robots are arranged at both longitudinal sides of the grid assembly structure; Correspondingly, the welding sequence followed by the welding robot in step 4 is: Taking the top plane of the grid assembly structure as a reference, the area where each casting cavity of the grid assembly structure is located is divided into four quadrants along the longitudinal axis of the grid assembly structure and the transverse axis of the grid assembly structure. The operating range of each welding robot corresponds to each casting cavity in a quadrant of the current diagonal distribution. The two welding robots perform the welding sequence of each casting cavity in the current corresponding quadrant synchronously; Each welding robot takes the casting cavity at the origin as the starting point for each casting cavity distributed in the current corresponding quadrant, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded; then, the next horizontal column between the welded horizontal columns is taken as the welding object area, and takes the casting cavity at the vertical axis as the starting point, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the selected horizontal column are welded; and so on.

[0017] Alternatively, further, there are four welding robots arranged at the working platform, and the four welding robots are arranged at both longitudinal sides of the grid assembly structure, with two on each side; Correspondingly, the welding sequence followed by the welding robot in step 4 is: Taking the top plane of the grid assembly structure as a reference, the area where each casting cavity of the grid assembly structure is located is divided into four quadrants along the longitudinal axis of the grid assembly structure and the transverse axis of the grid assembly structure. The operating range of each welding robot corresponds to each casting cavity in a quadrant. The welding robots corresponding to the two diagonally distributed quadrants perform the welding sequence of each casting cavity in the diagonal quadrant synchronously; Each welding robot takes the casting cavity at the origin as the starting point for each casting cavity distributed in the current corresponding quadrant, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded; then, the next horizontal column between the welded horizontal columns is taken as the welding object area, and takes the casting cavity at the vertical axis as the starting point, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the selected horizontal column are welded; and so on.

[0018] Furthermore, in step 4, the welding robot completes welding of the flat joint by using mixed gas and flat welding; The specific welding process is: weld foot height ≥5mm; welding voltage 28~32V; welding current 240~300A; welding speed 4~6mm / s; welding gun inclination angle 30~50°.

[0019] Furthermore, in step 4, the welding robot uses mixed gas and vertical welding to complete the welding of the vertical joint, and the welding gun uses L-shaped swing during the welding process; The specific welding process is: weld foot height ≥5mm; welding voltage 16~21V; welding current 130~180A; welding speed 0.7~1mm / s; left and right swing width 2~7mm; left and right dwell time 1~1.5s respectively; middle dwell time 0.1~0.3s; welding gun inclination angle 40~60°.

[0020] The above forming method is based on the automated welding operation characteristics of the welding robot, and performs automated welding on each casting cavity of the grid structure according to the set welding sequence, especially forming continuous arc welding on the four flat joints at the bottom plate and the four flat joints at the top plate, which has the technical characteristics of easy execution, high operation efficiency, and consistent weld quality. While ensuring quality, it is conducive to reducing the labor intensity of workers and reducing the number of workers, thereby reducing the manufacturing cost of the grid. Moreover, the above welding sequence method adapted to the welding robot can effectively control welding deformation to reliably ensure the quality of automated welding.

[0021] The beneficial technical effect of the present invention is that the above technical measures are aimed at the particularity of the above suspension bridge grid structure, and without making major structural changes, the through-welding hole structure in the casting cavity is removed to form a non-interrupted continuous weld in the casting cavity, which can effectively adapt to the automated welding operation of the welding robot. The welding robot automatically welds each casting cavity of the grid structure according to the set welding sequence, which can effectively control the welding deformation, has the technical characteristics of easy execution, high operation efficiency, and consistent weld quality, and effectively reduces the manufacturing cost of the grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A structural schematic diagram of the present invention.

[0023] Figure 2 It is a schematic diagram of the structure of the present invention after removing the top plate.

[0024] Figure 3 for Figure 2 Schematic diagram of the structure of a single casting cavity.

[0025] Figure 4 for Figure 2 Schematic diagram of the structure of a single casting cavity after the top plate is assembled.

[0026] Figure 5 The figure is a schematic diagram of the welding sequence followed by two welding robots when automatically welding the casting cavities of the present invention.

[0027] The meaning of the codes in the figure are: 1—bottom plate; 2—top plate; 3—longitudinal rib; 4—transverse rib; 5—casting cavity. DETAILED DESCRIPTION

[0028] The present invention relates to a cable saddle support structure of a suspension bridge, specifically a grid structure for a suspension bridge, and a forming method of the grid structure. The main technical solution of the present invention is specifically described below in combination with multiple embodiments. Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 The technical solution of the present invention is explained clearly and in detail; although other embodiments are not separately drawn with drawings, their main structures can still refer to the drawings of embodiment 1.

[0029] It should be noted that the drawings of the present invention are schematic, and unnecessary details have been simplified to clarify the technical purpose of the present invention, so as to avoid blurring the technical solution of the present invention that contributes to the prior art. In addition, the expressions "approximately", "substantially" and the like regarding quantity or matching relationship in the following text mean that reasonable assembly errors and processing errors in the industry are allowed to exist, and do not literally express absolute quantities or matching relationships.

[0030] Example 1 See also Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the grid structure of the present invention comprises a bottom plate 1, a top plate 2, a plurality of longitudinal ribs 3 and a plurality of transverse ribs 4, and the bottom plate 1, the top plate 2, the longitudinal ribs 3 and the transverse ribs 4 are all steel plate structures.

[0031] The bottom plate 1 and the top plate 2 are determined by the relative positions of the grid when it is installed in the suspension bridge structure. The bottom plate 1 is used for inserting the embedded steel bars, and the top plate 2 is used for installing the cable saddle.

[0032] The outline structure of each longitudinal rib 3 is basically a rectangular structure, with a straight bottom edge and a top edge, and the end outline is set according to the construction requirements; the height between the bottom edge and the top edge of the longitudinal rib 3 is about 430mm. Several longitudinal ribs 3 are arranged between the bottom plate 1 and the top plate 2 along the transverse bridge direction, with a spacing of about 490mm, and each longitudinal rib 3 is arranged vertically along the bridge direction. The longitudinal rib 3 is seated on the bottom plate 1 through the straight bottom edge, and the longitudinal rib 3 is seated on the top plate 2 through the straight top edge.

[0033] The outline structure of each transverse rib 4 is a rectangular structure (the transverse rib 4 allocated to the outside of the outermost longitudinal rib 3 is an exception), with a straight bottom edge and a straight top edge; the height between the bottom edge and the top edge of the transverse rib 4 is about 430mm. Several transverse ribs 4 are divided into multiple groups; multiple transverse ribs 4 in each group are arranged along the longitudinal spacing in each longitudinal channel between the bottom plate 1 and the top plate 2 (i.e., the space between adjacent longitudinal ribs 3), with a spacing distance of about 405mm, and each transverse rib 4 is arranged vertically in the transverse direction. The transverse rib 4 is seated on the bottom plate 1 through the straight bottom edge, and the transverse rib 4 is seated on the top plate 2 through the straight top edge. It should be noted that transverse ribs are arranged on the outside of the outermost longitudinal ribs 3, but the transverse ribs here only strengthen the longitudinal ribs 3, bottom plate 1 and top plate 2 at their locations, especially the longitudinal ribs 3 at their locations, so their structural form does not require too much, and they only need to form straight edges with the corresponding longitudinal ribs 3, bottom plate 1 and top plate 2 respectively.

[0034] In this way, the adjacent longitudinal ribs 3 and the adjacent transverse ribs 4 between the bottom plate 1 and the top plate 2 enclose a casting cavity 5 with an outline size of about 405 mm in length, 490 mm in width, and 430 mm in height (except for the outer side of the outermost longitudinal rib 3), that is, the width of the casting cavity 5 along the direction of the adjacent longitudinal ribs is about 490 mm, the length along the direction of the adjacent transverse ribs is about 405 mm, and the height along the direction of the bottom plate 1 and the top plate 2 is about 430 mm. The longitudinal ribs 3 enclosing the casting cavity 5 are fixedly connected to the bottom plate 1, the top plate 2, and the transverse ribs 4 by fillet weld structures, and the fillet welds on each side form a non-interrupted continuous weld, and the connected fillet welds form a non-interrupted continuous weld. The transverse ribs 4 enclosing the casting cavity 5 are fixedly connected to the bottom plate 1 and the top plate 2 by fillet weld structures, and the fillet welds on each side form a non-interrupted continuous weld, and the connected fillet welds form a non-interrupted continuous weld.

[0035] The bottom plate 1 has a bottom side pouring port connected to each pouring cavity 5 and having a profile smaller than the corresponding pouring cavity 5. The bottom side pouring port on the bottom plate 1 has a width of about 280 mm along the direction of the adjacent longitudinal ribs and a length of about 265 mm along the direction of the adjacent transverse ribs.

[0036] The top plate 2 has a top side pouring port connected to each pouring cavity 5 and having a smaller profile than the corresponding pouring cavity 5. The top side pouring port on the top plate 2 has a width of about 280 mm along the direction of the adjacent longitudinal ribs and a length of about 265 mm along the direction of the adjacent transverse ribs, so that the top side pouring port on the top plate 2 has a substantially equal profile to the bottom side pouring port on the bottom plate 1.

[0037] See also Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the grid structure is formed by welding with a welding robot, and the specific forming method includes the following process steps: Step 1. According to the design structure, establish a theoretical three-dimensional model that can be imported into the welding robot and recognized by the welding robot itself; The steel plates are cut and blanked to obtain a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs of corresponding structural shapes and sizes; Step 2. According to the design structure, several longitudinal ribs and several transverse ribs are arranged vertically and horizontally on the bottom plate in an upright manner, and assembled by spot welding. That is, each longitudinal rib is spot welded to the bottom plate, each transverse rib is also spot welded to the bottom plate, and each transverse rib is also spot welded to the corresponding longitudinal rib (such as Figure 2 , Figure 3 shown); Fix the assembled structure to the supporting fixture on the working platform by spot welding the horse plate; Two welding robots are arranged at the working platform, and the two welding robots are arranged at both longitudinal sides of the grid assembly structure; Step 3. Import the theoretical 3D model into each welding robot (i.e., import it into the operating system of the corresponding welding robot), and the welding robot solves the theoretical 3D model, extracts and generates each weld to be welded according to the set welding process requirements; Step 4. The two welding robots respectively perform global visual scanning on the assembled structure through the global vision system to obtain the scanned 3D cloud map, and globally match the 3D cloud map with the theoretical 3D model. After the matching is completed, the welding task is generated according to the welding sequence set as follows to effectively control the deformation of the grid structure caused by welding and ensure the quality of the weld; In order to control the deformation of the grid structure caused by welding, the welding sequence followed by the two welding robots is as follows (e.g. Figure 5 shown): Taking the top plane of the grille assembly structure as a reference, the areas where the casting cavities of the grille assembly structure are located are divided into the first quadrant, the second quadrant, the third quadrant and the fourth quadrant along the longitudinal axis of the grille assembly structure and the transverse axis along the transverse axis of the grille assembly structure. The first quadrant and the fourth quadrant are diagonally distributed, and the second quadrant and the third quadrant are diagonally distributed; the operating range of each welding robot corresponds to the casting cavities in a quadrant of the current diagonal distribution, such as the current operating range of the first welding robot is the casting cavities in the first quadrant, and the current operating range of the second welding robot is the casting cavities in the fourth quadrant; or, when the current operating range of the first welding robot is the casting cavities in the second quadrant, the current operating range of the second welding robot is the casting cavities in the third quadrant; The two welding robots perform the welding sequence of each casting cavity in the current corresponding quadrant synchronously; The principle followed by each welding robot for the welding sequence of the casting cavities distributed in the current corresponding quadrant is to start from the casting cavity at the origin, and perform automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded, and then jump along the vertical axis to complete all automatic welding of the next horizontal column (that is, the next horizontal column between the horizontal columns that have been welded is taken as the welding object area), and so on; Taking the welding operation of the first welding robot in the first quadrant as an example, the welding sequence is as follows: Take the first order horizontal row at the horizontal axis as the welding object area, first weld the casting cavity at position A1, then skip the casting cavity at position B1 and directly weld the casting cavity at position C1, and so on if there are other casting cavities outside position C1; after the first order of cavity skipping welding of the current horizontal row is completed, take the casting cavity at position B1 as the starting point and proceed with the second order of cavity skipping welding of the current horizontal row along the horizontal axis until all the casting cavities in the current horizontal row are welded (this is the case for the non-enclosed cavity outside the outermost longitudinal rib); Then, the second sequential transverse row is skipped, and the third sequential transverse row separated from the first sequential transverse row that has been welded is used as the next welding object area; when the third sequential transverse row is automatically welded, the cavity skipping sequence is the same as the welding of the first sequential transverse row, that is, the A3 casting cavity is welded first, and then the B3 casting cavity is skipped and the C3 casting cavity is directly welded, and if there are other casting cavities outside the C3 position, the same is true; after the first sequential cavity skipping welding of the third sequential transverse row is completed, the B3 casting cavity is used as the starting point to perform the second sequential cavity skipping welding of the third sequential transverse row along the horizontal axis, until all the casting cavities of the third sequential transverse row are welded; Then, the fourth sequential transverse row is skipped, and the fifth sequential transverse row separated from the completed third sequential transverse row is used as the next welding target area; And so on; After all the odd-numbered transverse columns relative to the horizontal axis are welded, the second-order transverse column between the first-order transverse column and the third-order transverse column that have been welded is used as the next welding target area; after all the casting cavities in the second-order transverse column are welded according to the above-mentioned skipping order, the fourth-order transverse column between the third-order transverse column and the fifth-order transverse column that have been welded is used as the next welding target area; and so on, until all the even-numbered transverse columns relative to the horizontal axis are welded; At this point, each casting cavity in the first quadrant has been welded sequentially; After the two welding robots synchronously weld the casting cavities in the two diagonally distributed quadrants, they switch to the other two diagonally distributed quadrants and repeat the above welding sequence to complete the automatic welding; In order to ensure the quality of the weld and improve the welding efficiency, when the welding robot performs automatic welding operation on each monomer casting cavity, the robot arm of the welding robot extends from the opening surrounded by the transverse ribs and the longitudinal ribs into the current casting cavity (such as Figure 3 As shown in the figure), the automatic welding process of the welding robot for the current casting cavity is: First, weld the four vertical joints between the transverse ribs and the longitudinal ribs in sequence to form fillet welds; The specific process adopted by the welding robot for the vertical joint welding is: the welding is completed by mixed gas and vertical welding, and the welding gun adopts L-shaped swing during the welding process; the welding foot height is about 12mm; the welding voltage is about 21V; the welding current is about 150A; the welding speed is about 1mm / s; the left and right swing width is about 6mm; the left and right dwell time are about 1.3s respectively; the middle dwell time is about 0.2s; the welding gun inclination angle is about 55°; Then, the four flat joints at the bottom plate are continuously welded in a continuous arc manner, that is, the four flat joints at the bottom plate form non-interrupted continuous welding in the surrounding directions, and finally form fillet welds; The specific process used by the welding robot for continuous welding of flat joints is: using mixed gas, two layers and three passes of flat welding to complete the welding; the weld foot height is about 12mm; the welding voltage is about 32V; the welding current is about 260A; the welding speed is about 6mm / s; the welding gun inclination angle is about 37°; Compared with the welding process of the flat joint, the welding process of the vertical joint can effectively prevent the gravity drop of the welding water, so as to reliably ensure the welding quality of the vertical weld. Step 5. According to the design structure, spot weld the top plate to each longitudinal rib and each transverse rib (such as Figure 4 shown); Step 6. Turn the relative positions of the bottom plate and the top plate on the work platform so that the top plate is facing downward and the bottom plate is facing upward; Spot weld the turned structure to the supporting fixture on the working platform; Step 7. Repeat step 4; The mechanical arm of the welding robot extends from the bottom side pouring port of the bottom plate into the current pouring cavity, and continuously welds four flat joints at the top plate in the current pouring cavity in a continuous arc manner (compared to step 4 as a whole, there is no welding of vertical joints), completing automatic welding; Step 8. Perform quality inspection on the welded grid. The specific technical standard for quality inspection is to use magnetic particle inspection. The magnetic particle inspection (MT) inspection should comply with the provisions of GB / T 26952-2011 Level 1. Step 9. The grids that have passed the quality inspection will be transferred to the heat treatment process and the finishing process in sequence until the finished product (such as Figure 1 as shown).

[0038] Example 2 See also Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the grid structure of the present invention comprises a bottom plate 1, a top plate 2, a plurality of longitudinal ribs 3 and a plurality of transverse ribs 4, and the bottom plate 1, the top plate 2, the longitudinal ribs 3 and the transverse ribs 4 are all steel plate structures.

[0039] The bottom plate 1 and the top plate 2 are determined by the relative positions of the grid when it is installed in the suspension bridge structure. The bottom plate 1 is used for inserting the embedded steel bars, and the top plate 2 is used for installing the cable saddle.

[0040] The outline structure of each longitudinal rib 3 is basically a rectangular structure, with a straight bottom edge and a top edge, and the end outline is set according to the construction requirements; the height between the bottom edge and the top edge of the longitudinal rib 3 is about 450mm. Several longitudinal ribs 3 are arranged along the transverse bridge direction between the bottom plate 1 and the top plate 2, with a spacing of about 645mm, and each longitudinal rib 3 is arranged vertically along the bridge direction. The longitudinal rib 3 is seated on the bottom plate 1 through the straight bottom edge, and the longitudinal rib 3 is seated on the top plate 2 through the straight top edge.

[0041] The outline structure of each transverse rib 4 is a rectangular structure (the transverse rib 4 allocated to the outside of the outermost longitudinal rib 3 is an exception), with a straight bottom edge and a straight top edge; the height between the bottom edge and the top edge of the transverse rib 4 is about 450mm. Several transverse ribs 4 are divided into multiple groups; multiple transverse ribs 4 in each group are arranged along the longitudinal spacing in each longitudinal channel between the bottom plate 1 and the top plate 2 (i.e., the space between adjacent longitudinal ribs 3), with a spacing distance of about 395mm, and each transverse rib 4 is arranged vertically in the transverse direction. The transverse rib 4 is seated on the bottom plate 1 through the straight bottom edge, and the transverse rib 4 is seated on the top plate 2 through the straight top edge. It should be noted that transverse ribs are arranged on the outside of the outermost longitudinal ribs 3, but the transverse ribs here only strengthen the longitudinal ribs 3, bottom plate 1 and top plate 2 at their locations, especially the longitudinal ribs 3 at their locations, so their structural form does not require too much, and they only need to form straight edges with the corresponding longitudinal ribs 3, bottom plate 1 and top plate 2 respectively.

[0042] In this way, the adjacent longitudinal ribs 3 and the adjacent transverse ribs 4 between the bottom plate 1 and the top plate 2 form a casting cavity 5 with an outline size of about 395 mm in length, 645 mm in width, and 450 mm in height (except for the outer side of the outermost longitudinal rib 3), that is, the width of the casting cavity 5 along the direction of the adjacent longitudinal ribs is about 645 mm, the length along the direction of the adjacent transverse ribs is about 395 mm, and the height along the direction of the bottom plate 1 and the top plate 2 is about 450 mm. The longitudinal ribs 3 that enclose the casting cavity 5 are fixedly connected to the bottom plate 1, the top plate 2, and the transverse ribs 4 respectively through fillet weld structures, and the fillet welds on each side form a non-interrupted continuous weld, and the connected fillet welds form a non-interrupted continuous weld. The transverse ribs 4 that enclose the casting cavity 5 are fixedly connected to the bottom plate 1 and the top plate 2 respectively through fillet weld structures, and the fillet welds on each side form a non-interrupted continuous weld, and the connected fillet welds form a non-interrupted continuous weld.

[0043] The bottom plate 1 has a bottom side pouring port connected to each pouring cavity 5 and having a profile smaller than the corresponding pouring cavity 5. The bottom side pouring port on the bottom plate 1 has a width of about 505 mm along the direction of the adjacent longitudinal ribs and a length of about 305 mm along the direction of the adjacent transverse ribs.

[0044] The top plate 2 has a top side pouring port connected to each pouring cavity 5 and having a smaller profile than the corresponding pouring cavity 5. The top side pouring port on the top plate 2 has a width of about 505 mm along the direction of the adjacent longitudinal ribs and a length of about 305 mm along the direction of the adjacent transverse ribs, so that the top side pouring port on the top plate 2 has a substantially equal profile to the bottom side pouring port on the bottom plate 1.

[0045] See also Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the grid structure is formed by welding with a welding robot, and the specific forming method includes the following process steps: Step 1. According to the design structure, establish a theoretical three-dimensional model that can be imported into the welding robot and recognized by the welding robot itself; The steel plates are cut and blanked to obtain a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs of corresponding structural shapes and sizes; Step 2. According to the design structure, several longitudinal ribs and several transverse ribs are arranged vertically and horizontally on the bottom plate in an upright manner, and assembled by spot welding. That is, each longitudinal rib is spot welded to the bottom plate, each transverse rib is also spot welded to the bottom plate, and each transverse rib is also spot welded to the corresponding longitudinal rib (such as Figure 2 , Figure 3 shown); Fix the assembled structure to the supporting fixture on the working platform by spot welding the horse plate; There are four welding robots arranged on the working platform. These four welding robots are arranged on both sides of the grid assembly structure in the longitudinal direction, with two on each side. Step 3. Import the theoretical 3D model into each welding robot (i.e., import it into the operating system of the corresponding welding robot), and the welding robot solves the theoretical 3D model, extracts and generates each weld to be welded according to the set welding process requirements; Step 4. The four welding robots respectively perform global visual scanning on the assembled structure through the global vision system to obtain the scanned 3D cloud map, and globally match the 3D cloud map with the theoretical 3D model. After the matching is completed, the welding task is generated according to the welding sequence set as follows to effectively control the deformation of the grid structure caused by welding and ensure the quality of the weld; In order to control the deformation of the grid structure caused by welding, the welding sequence followed by the four welding robots is as follows (e.g. Figure 5 shown): Taking the top plane of the grille assembly structure as a reference, the areas where the casting cavities of the grille assembly structure are located are divided into the first quadrant, the second quadrant, the third quadrant and the fourth quadrant along the longitudinal axis of the grille assembly structure and the transverse axis along the transverse axis of the grille assembly structure. The first quadrant and the fourth quadrant are diagonally distributed, and the second quadrant and the third quadrant are diagonally distributed; the operating range of each welding robot corresponds to each casting cavity in a quadrant, such as the operating range of the first welding robot is each casting cavity in the first quadrant, the operating range of the second welding robot is each casting cavity in the second quadrant, the operating range of the third welding robot is each casting cavity in the third quadrant, and the operating range of the fourth welding robot is each casting cavity in the fourth quadrant; It is required that the two welding robots corresponding to the two diagonally distributed quadrants perform the welding sequence of each casting cavity in the diagonal quadrant synchronously; of course, the effect and efficiency of the synchronous action of four welding robots are better; The principle followed by each welding robot for the welding sequence of the casting cavities distributed in the current corresponding quadrant is to start from the casting cavity at the origin, and perform automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded, and then jump along the vertical axis to complete all automatic welding of the next horizontal column (that is, the next horizontal column between the horizontal columns that have been welded is taken as the welding object area), and so on; Taking the welding operation of the first welding robot in the first quadrant as an example, the welding sequence is as follows: Take the first order horizontal row at the horizontal axis as the welding object area, first weld the casting cavity at position A1, then skip the casting cavity at position B1 and directly weld the casting cavity at position C1, and so on if there are other casting cavities outside position C1; after the first order of cavity skipping welding of the current horizontal row is completed, take the casting cavity at position B1 as the starting point and proceed with the second order of cavity skipping welding of the current horizontal row along the horizontal axis until all the casting cavities in the current horizontal row are welded (this is the case for the non-enclosed cavity outside the outermost longitudinal rib); Then, the second sequential transverse row is skipped, and the third sequential transverse row separated from the first sequential transverse row that has been welded is used as the next welding object area; when the third sequential transverse row is automatically welded, the cavity skipping sequence is the same as the welding of the first sequential transverse row, that is, the A3 casting cavity is welded first, and then the B3 casting cavity is skipped and the C3 casting cavity is directly welded, and if there are other casting cavities outside the C3 position, the same is true; after the first sequential cavity skipping welding of the third sequential transverse row is completed, the B3 casting cavity is used as the starting point to perform the second sequential cavity skipping welding of the third sequential transverse row along the horizontal axis, until all the casting cavities of the third sequential transverse row are welded; Then, the fourth sequential transverse row is skipped, and the fifth sequential transverse row separated from the completed third sequential transverse row is used as the next welding target area; And so on; After all the odd-numbered transverse columns relative to the horizontal axis are welded, the second-order transverse column between the first-order transverse column and the third-order transverse column that have been welded is used as the next welding target area; after all the casting cavities in the second-order transverse column are welded according to the above-mentioned skipping order, the fourth-order transverse column between the third-order transverse column and the fifth-order transverse column that have been welded is used as the next welding target area; and so on, until all the even-numbered transverse columns relative to the horizontal axis are welded; At this point, each casting cavity in the first quadrant has been welded sequentially; The two welding robots corresponding to the diagonal quadrants automatically and synchronously complete the welding of each casting cavity within the working range; In order to ensure the quality of the weld and improve the welding efficiency, when the welding robot performs automatic welding operation on each monomer casting cavity, the robot arm of the welding robot extends from the opening surrounded by the transverse ribs and the longitudinal ribs into the current casting cavity (such as Figure 3 As shown in the figure), the automatic welding process of the welding robot for the current casting cavity is: First, weld the four vertical joints between the transverse ribs and the longitudinal ribs in sequence to form fillet welds; The specific process adopted by the welding robot for the vertical joint welding is: the welding is completed by mixed gas and vertical welding, and the welding gun adopts L-shaped swing during the welding process; the welding foot height is about 10mm; the welding voltage is about 16V; the welding current is about 130A; the welding speed is about 0.7mm / s; the left and right swing width is about 5mm; the left and right dwell time are about 1s respectively; the middle dwell time is about 0.1s; the welding gun inclination angle is about 60°; Then, the four flat joints at the bottom plate are continuously welded in a continuous arc manner, that is, the four flat joints at the bottom plate form non-interrupted continuous welding in the surrounding directions, and finally form fillet welds; The specific process used by the welding robot for continuous welding of flat joints is: using mixed gas and single-pass flat welding to complete welding; the weld foot height is about 5mm; the welding voltage is about 28V; the welding current is about 240A; the welding speed is about 4mm / s; the welding gun inclination angle is about 50°; Compared with the welding process of the flat joint, the welding process of the vertical joint can effectively prevent the gravity drop of the welding water, so as to reliably ensure the welding quality of the vertical weld. Step 5. According to the design structure, spot weld the top plate to each longitudinal rib and each transverse rib (such as Figure 4 shown); Step 6. Turn the relative positions of the bottom plate and the top plate on the work platform so that the top plate is facing downward and the bottom plate is facing upward; Spot weld the turned structure to the supporting fixture on the working platform; Step 7. Repeat step 4; The mechanical arm of the welding robot extends from the bottom side pouring port of the bottom plate into the current pouring cavity, and continuously welds four flat joints at the top plate in the current pouring cavity in a continuous arc manner (compared to step 4 as a whole, there is no welding of vertical joints), completing automatic welding; Step 8. Perform quality inspection on the welded grid. The specific technical standard for quality inspection is to use magnetic particle inspection. The magnetic particle inspection (MT) inspection should comply with the provisions of GB / T 26952-2011 Level 1. Step 9. The grids that have passed the quality inspection will be transferred to the heat treatment process and the finishing process in sequence until the finished product (such as Figure 1 as shown).

[0046] Example 3 The rest of the contents of this embodiment are the same as those of Embodiment 1 or 2, except for the specific structural form of the grille.

[0047] That is, the grid structure of the present invention comprises a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs, and the bottom plate, the top plate, the longitudinal ribs and the transverse ribs are all steel plate structures.

[0048] The bottom plate and top plate are determined by the relative positions of the grille when it is installed in the suspension bridge structure. The bottom plate is used for installing embedded steel bars, and the top plate is used for installing cable saddles.

[0049] The outline structure of each longitudinal rib is basically a rectangular structure with a straight bottom and top. The end outline is set according to the construction requirements. The height between the bottom and top of the longitudinal rib is about 420mm. Several longitudinal ribs are arranged along the transverse bridge direction between the bottom plate and the top plate, with a spacing of about 550mm. Each longitudinal rib is arranged vertically along the bridge direction. The longitudinal rib is seated on the bottom plate through the straight bottom edge, and the longitudinal rib is seated on the top plate through the straight top edge.

[0050] The outline structure of each transverse rib is a rectangular structure (except for the transverse ribs allocated on the outside of the outermost longitudinal ribs), with straight bottom and top edges; the height between the bottom and top edges of the transverse ribs is about 420mm. Several transverse ribs are divided into multiple groups; multiple transverse ribs in each group are arranged along the longitudinal spacing in each longitudinal channel between the bottom plate and the top plate (i.e., the space between adjacent longitudinal ribs), with a spacing of about 410mm, and each transverse rib is arranged vertically in the transverse direction. The transverse ribs are seated on the bottom plate through the straight bottom edge, and the transverse ribs are seated on the top plate through the straight top edge. It should be noted that transverse ribs are also arranged on the outside of the outermost longitudinal ribs, but the transverse ribs here only play a reinforcing role on the longitudinal ribs, bottom plate and top plate at the location, especially for the longitudinal ribs at the location, so there are no too many requirements for their structural form, and they only need to form straight edges with the corresponding longitudinal ribs, bottom plate and top plate.

[0051] In this way, the adjacent longitudinal ribs and adjacent transverse ribs between the bottom plate and the top plate enclose a casting cavity with an outline size of about 410 mm in length, 550 mm in width, and 420 mm in height (except for the outer side of the outermost longitudinal ribs), that is, the width of the casting cavity along the direction of the adjacent longitudinal ribs is about 550 mm, the length along the direction of the adjacent transverse ribs is about 410 mm, and the height along the direction of the bottom plate and the top plate is about 420 mm. The longitudinal ribs enclosing the casting cavity are fixedly connected to the bottom plate, the top plate and the transverse ribs by fillet weld structures, and the fillet welds on each side form an uninterrupted continuous weld, and the connected fillet welds form an uninterrupted continuous weld. The transverse ribs enclosing the casting cavity are fixedly connected to the bottom plate and the top plate by fillet weld structures, and the fillet welds on each side form an uninterrupted continuous weld, and the connected fillet welds form an uninterrupted continuous weld.

[0052] The bottom plate has a bottom side pouring port connected to each pouring cavity and having a profile smaller than the corresponding pouring cavity. The bottom side pouring port on the bottom plate has a width of about 390 mm along the direction of the adjacent longitudinal ribs and a length of about 280 mm along the direction of the adjacent transverse ribs.

[0053] The top plate has a top side pouring port connected to each pouring cavity and having a smaller profile than the corresponding pouring cavity. The top side pouring port on the top plate has a width of about 390 mm along the direction of the adjacent longitudinal ribs and a length of about 280 mm along the direction of the adjacent transverse ribs, so that the top side pouring port on the top plate has a substantially equal profile structure to the bottom side pouring port on the bottom plate.

[0054] The above-mentioned grid structure is formed by welding with a welding robot, and the specific forming method includes the following process steps: Step 1. According to the design structure, establish a theoretical three-dimensional model that can be imported into the welding robot and recognized by the welding robot itself; The steel plates are cut and blanked to obtain a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs of corresponding structural shapes and sizes; Step 2. According to the designed structure, a plurality of longitudinal ribs and a plurality of transverse ribs are arranged vertically and horizontally on the bottom plate in an upright manner, and assembled by spot welding, that is, each longitudinal rib is spot welded to the bottom plate, each transverse rib is also spot welded to the bottom plate, and each transverse rib is also spot welded to the corresponding longitudinal rib; Fix the assembled structure to the supporting fixture on the working platform by spot welding the horse plate; Two welding robots are arranged at the working platform, and the two welding robots are arranged at both longitudinal sides of the grid assembly structure; Step 3. Import the theoretical 3D model into each welding robot (i.e., import it into the operating system of the corresponding welding robot), and the welding robot solves the theoretical 3D model, extracts and generates each weld to be welded according to the set welding process requirements; Step 4. The two welding robots respectively perform global visual scanning on the assembled structure through the global vision system to obtain the scanned 3D cloud map, and globally match the 3D cloud map with the theoretical 3D model. After the matching is completed, the welding task is generated according to the welding sequence set as follows to effectively control the deformation of the grid structure caused by welding and ensure the quality of the weld; In order to control the deformation of the grid structure caused by welding, the welding sequence followed by the two welding robots is: Taking the top plane of the grille assembly structure as a reference, the areas where the casting cavities of the grille assembly structure are located are divided into the first quadrant, the second quadrant, the third quadrant and the fourth quadrant along the longitudinal axis of the grille assembly structure and the transverse axis along the transverse axis of the grille assembly structure. The first quadrant and the fourth quadrant are diagonally distributed, and the second quadrant and the third quadrant are diagonally distributed; the operating range of each welding robot corresponds to the casting cavities in a quadrant of the current diagonal distribution, such as the current operating range of the first welding robot is the casting cavities in the first quadrant, and the current operating range of the second welding robot is the casting cavities in the fourth quadrant; or, when the current operating range of the first welding robot is the casting cavities in the second quadrant, the current operating range of the second welding robot is the casting cavities in the third quadrant; The two welding robots perform the welding sequence of each casting cavity in the current corresponding quadrant synchronously; The principle followed by each welding robot for the welding sequence of the casting cavities distributed in the current corresponding quadrant is to start from the casting cavity at the origin, and perform automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded, and then jump along the vertical axis to complete all automatic welding of the next horizontal column (that is, the next horizontal column between the horizontal columns that have been welded is taken as the welding object area), and so on; Taking the welding operation of the first welding robot in the first quadrant as an example, the welding sequence is as follows: Take the first order horizontal row at the horizontal axis as the welding object area, first weld the casting cavity at position A1, then skip the casting cavity at position B1 and directly weld the casting cavity at position C1, and so on if there are other casting cavities outside position C1; after the first order of cavity skipping welding of the current horizontal row is completed, take the casting cavity at position B1 as the starting point and proceed with the second order of cavity skipping welding of the current horizontal row along the horizontal axis until all the casting cavities in the current horizontal row are welded (this is the case for the non-enclosed cavity outside the outermost longitudinal rib); Then, the second sequential transverse row is skipped, and the third sequential transverse row separated from the first sequential transverse row that has been welded is used as the next welding object area; when the third sequential transverse row is automatically welded, the cavity skipping sequence is the same as the welding of the first sequential transverse row, that is, the A3 casting cavity is welded first, and then the B3 casting cavity is skipped and the C3 casting cavity is directly welded, and if there are other casting cavities outside the C3 position, the same is true; after the first sequential cavity skipping welding of the third sequential transverse row is completed, the B3 casting cavity is used as the starting point to perform the second sequential cavity skipping welding of the third sequential transverse row along the horizontal axis, until all the casting cavities of the third sequential transverse row are welded; Then, the fourth sequential transverse row is skipped, and the fifth sequential transverse row separated from the completed third sequential transverse row is used as the next welding target area; And so on; After all the odd-numbered transverse columns relative to the horizontal axis are welded, the second-order transverse column between the first-order transverse column and the third-order transverse column that have been welded is used as the next welding target area; after all the casting cavities in the second-order transverse column are welded according to the above-mentioned skipping order, the fourth-order transverse column between the third-order transverse column and the fifth-order transverse column that have been welded is used as the next welding target area; and so on, until all the even-numbered transverse columns relative to the horizontal axis are welded; At this point, each casting cavity in the first quadrant has been welded sequentially; After the two welding robots synchronously weld the casting cavities in the two diagonally distributed quadrants, they switch to the other two diagonally distributed quadrants and repeat the above welding sequence to complete the automatic welding; In order to ensure the quality of the weld and improve the welding efficiency, when the welding robot performs automatic welding operation on each monomer casting cavity, the mechanical arm of the welding robot extends into the current casting cavity from the opening surrounded by the transverse ribs and the longitudinal ribs. The automatic welding process of the welding robot on the current casting cavity is: First, weld the four vertical joints between the transverse ribs and the longitudinal ribs in sequence to form fillet welds; The specific process adopted by the welding robot for the vertical joint welding is: the welding is completed by mixed gas and vertical welding, and the welding gun adopts L-shaped swing during the welding process; the welding foot height is about 8mm; the welding voltage is about 18V; the welding current is about 180A; the welding speed is about 0.8mm / s; the left and right swing width is about 4mm; the left and right dwell time are about 1.5s respectively; the middle dwell time is about 0.3s; the welding gun inclination angle is about 40°; Then, the four flat joints at the bottom plate are continuously welded in a continuous arc manner, that is, the four flat joints at the bottom plate form non-interrupted continuous welding in the surrounding directions, and finally form fillet welds; The specific process used by the welding robot for continuous welding of flat joints is: using mixed gas, two layers and three passes of flat welding to complete the welding; the weld foot height is about 14mm; the welding voltage is about 30V; the welding current is about 300A; the welding speed is about 5mm / s; the welding gun inclination angle is about 30°; Compared with the welding process of the flat joint, the welding process of the vertical joint can effectively prevent the gravity drop of the welding water, so as to reliably ensure the welding quality of the vertical weld. Step 5. According to the designed structure, spot weld the top plate onto each longitudinal rib and each transverse rib; Step 6. Turn the relative positions of the bottom plate and the top plate on the work platform so that the top plate is facing downward and the bottom plate is facing upward; Spot weld the turned structure to the supporting fixture on the working platform; Step 7. Repeat step 4; The mechanical arm of the welding robot extends from the bottom side pouring port of the bottom plate into the current pouring cavity, and continuously welds four flat joints at the top plate in the current pouring cavity in a continuous arc manner (compared to step 4 as a whole, there is no welding of vertical joints), completing automatic welding; Step 8. Perform quality inspection on the welded grid. The specific technical standard for quality inspection is to use magnetic particle inspection. The magnetic particle inspection (MT) inspection should comply with the provisions of GB / T 26952-2011 Level 1. Step 9. The grilles that have passed the quality inspection will be transferred to the heat treatment process and the finishing process in sequence until they are finished products.

[0055] Example 4 The rest of the contents of this embodiment are the same as those of Embodiment 1 or 2, except for the specific structural form of the grille.

[0056] That is, the grid structure of the present invention comprises a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs, and the bottom plate, the top plate, the longitudinal ribs and the transverse ribs are all steel plate structures.

[0057] The bottom plate and top plate are determined by the relative positions of the grille when it is installed in the suspension bridge structure. The bottom plate is used for installing embedded steel bars, and the top plate is used for installing cable saddles.

[0058] The outline structure of each longitudinal rib is basically a rectangular structure with a straight bottom and top. The end outline is set according to the construction requirements. The height between the bottom and top of the longitudinal rib is about 430mm. Several longitudinal ribs are arranged along the transverse bridge direction between the bottom plate and the top plate, with a spacing of about 610mm. Each longitudinal rib is arranged vertically along the bridge direction. The longitudinal rib is seated on the bottom plate through the straight bottom edge, and the longitudinal rib is seated on the top plate through the straight top edge.

[0059] The outline structure of each transverse rib is a rectangular structure (except for the transverse ribs allocated on the outside of the outermost longitudinal ribs), with straight bottom and top edges; the height between the bottom and top edges of the transverse ribs is about 430mm. Several transverse ribs are divided into multiple groups; multiple transverse ribs in each group are arranged along the longitudinal spacing in each longitudinal channel between the bottom plate and the top plate (i.e., the space between adjacent longitudinal ribs), with a spacing of about 420mm, and each transverse rib is arranged vertically in the transverse direction. The transverse ribs are seated on the bottom plate through the straight bottom edge, and the transverse ribs are seated on the top plate through the straight top edge. It should be noted that transverse ribs are also arranged on the outside of the outermost longitudinal ribs, but the transverse ribs here only play a reinforcing role on the longitudinal ribs, bottom plate and top plate at the location, especially for the longitudinal ribs at the location, so there are no excessive requirements for their structural form, and they only need to form straight edges with the corresponding longitudinal ribs, bottom plate and top plate.

[0060] In this way, the adjacent longitudinal ribs and adjacent transverse ribs between the bottom plate and the top plate enclose a casting cavity with an outline size of about 420mm in length, 610mm in width, and 430mm in height (except for the outer side of the outermost longitudinal ribs), that is, the width of the casting cavity along the direction of the adjacent longitudinal ribs is about 610mm, the length along the direction of the adjacent transverse ribs is about 420mm, and the height along the direction of the bottom plate and the top plate is about 430mm. The longitudinal ribs enclosing the casting cavity are fixedly connected to the bottom plate, the top plate and the transverse ribs by fillet weld structures, and the fillet welds on each side form an uninterrupted continuous weld, and the connected fillet welds form an uninterrupted continuous weld. The transverse ribs enclosing the casting cavity are fixedly connected to the bottom plate and the top plate by fillet weld structures, and the fillet welds on each side form an uninterrupted continuous weld, and the connected fillet welds form an uninterrupted continuous weld.

[0061] The bottom plate has a bottom side pouring port connected to each pouring cavity and having a profile smaller than the corresponding pouring cavity. The bottom side pouring port on the bottom plate has a width of about 430 mm along the direction of the adjacent longitudinal ribs and a length of about 295 mm along the direction of the adjacent transverse ribs.

[0062] The top plate has a top side pouring port connected to each pouring cavity and having a smaller profile than the corresponding pouring cavity. The top side pouring port on the top plate has a width of about 430 mm along the direction of the adjacent longitudinal ribs and a length of about 295 mm along the direction of the adjacent transverse ribs, so that the top side pouring port on the top plate has a profile structure substantially equal to that of the bottom side pouring port on the bottom plate.

[0063] The above-mentioned grid structure is formed by welding with a welding robot, and the specific forming method includes the following process steps: Step 1. According to the design structure, establish a theoretical three-dimensional model that can be imported into the welding robot and recognized by the welding robot itself; The steel plates are cut and blanked to obtain a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs of corresponding structural shapes and sizes; Step 2. According to the designed structure, a plurality of longitudinal ribs and a plurality of transverse ribs are arranged vertically and horizontally on the bottom plate in an upright manner, and assembled by spot welding, that is, each longitudinal rib is spot welded to the bottom plate, each transverse rib is also spot welded to the bottom plate, and each transverse rib is also spot welded to the corresponding longitudinal rib; Fix the assembled structure to the supporting fixture on the working platform by spot welding the horse plate; There are four welding robots arranged on the working platform. These four welding robots are arranged on both sides of the grid assembly structure in the longitudinal direction, with two on each side. Step 3. Import the theoretical 3D model into each welding robot (i.e., import it into the operating system of the corresponding welding robot), and the welding robot solves the theoretical 3D model, extracts and generates each weld to be welded according to the set welding process requirements; Step 4. The four welding robots respectively perform global visual scanning on the assembled structure through the global vision system to obtain the scanned 3D cloud map, and globally match the 3D cloud map with the theoretical 3D model. After the matching is completed, the welding task is generated according to the welding sequence set as follows to effectively control the deformation of the grid structure caused by welding and ensure the quality of the weld; In order to control the deformation of the grid structure caused by welding, the welding sequence followed by the four welding robots is: Taking the top plane of the grille assembly structure as a reference, the areas where the casting cavities of the grille assembly structure are located are divided into the first quadrant, the second quadrant, the third quadrant and the fourth quadrant along the longitudinal axis of the grille assembly structure and the transverse axis along the transverse axis of the grille assembly structure. The first quadrant and the fourth quadrant are diagonally distributed, and the second quadrant and the third quadrant are diagonally distributed; the operating range of each welding robot corresponds to each casting cavity in a quadrant, such as the operating range of the first welding robot is each casting cavity in the first quadrant, the operating range of the second welding robot is each casting cavity in the second quadrant, the operating range of the third welding robot is each casting cavity in the third quadrant, and the operating range of the fourth welding robot is each casting cavity in the fourth quadrant; It is required that the two welding robots corresponding to the two diagonally distributed quadrants perform the welding sequence of each casting cavity in the diagonal quadrant synchronously; of course, the effect and efficiency of the synchronous action of four welding robots are better; The principle followed by each welding robot for the welding sequence of the casting cavities distributed in the current corresponding quadrant is to start from the casting cavity at the origin, and perform automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded, and then jump along the vertical axis to complete all automatic welding of the next horizontal column (that is, the next horizontal column between the horizontal columns that have been welded is taken as the welding object area), and so on; Taking the welding operation of the first welding robot in the first quadrant as an example, the welding sequence is as follows: Take the first order horizontal row at the horizontal axis as the welding object area, first weld the casting cavity at position A1, then skip the casting cavity at position B1 and directly weld the casting cavity at position C1, and so on if there are other casting cavities outside position C1; after the first order of cavity skipping welding of the current horizontal row is completed, take the casting cavity at position B1 as the starting point and proceed with the second order of cavity skipping welding of the current horizontal row along the horizontal axis until all the casting cavities in the current horizontal row are welded (this is the case for the non-enclosed cavity outside the outermost longitudinal rib); Then, the second sequential transverse row is skipped, and the third sequential transverse row separated from the first sequential transverse row that has been welded is used as the next welding object area; when the third sequential transverse row is automatically welded, the cavity skipping sequence is the same as the welding of the first sequential transverse row, that is, the A3 casting cavity is welded first, and then the B3 casting cavity is skipped and the C3 casting cavity is directly welded, and if there are other casting cavities outside the C3 position, the same is true; after the first sequential cavity skipping welding of the third sequential transverse row is completed, the B3 casting cavity is used as the starting point to perform the second sequential cavity skipping welding of the third sequential transverse row along the horizontal axis, until all the casting cavities of the third sequential transverse row are welded; Then, the fourth sequential transverse row is skipped, and the fifth sequential transverse row separated from the completed third sequential transverse row is used as the next welding target area; And so on; After all the odd-numbered transverse columns relative to the horizontal axis are welded, the second-order transverse column between the first-order transverse column and the third-order transverse column that have been welded is used as the next welding target area; after all the casting cavities in the second-order transverse column are welded according to the above-mentioned skipping order, the fourth-order transverse column between the third-order transverse column and the fifth-order transverse column that have been welded is used as the next welding target area; and so on, until all the even-numbered transverse columns relative to the horizontal axis are welded; At this point, each casting cavity in the first quadrant has been welded sequentially; The two welding robots corresponding to the diagonal quadrants automatically and synchronously complete the welding of each casting cavity within the working range; In order to ensure the quality of the weld and improve the welding efficiency, when the welding robot performs automatic welding operation on each monomer casting cavity, the mechanical arm of the welding robot extends into the current casting cavity from the opening surrounded by the transverse ribs and the longitudinal ribs. The automatic welding process of the welding robot on the current casting cavity is: First, weld the four vertical joints between the transverse ribs and the longitudinal ribs in sequence to form fillet welds; The specific process adopted by the welding robot for the vertical joint welding is: the welding is completed by mixed gas and vertical welding, and the welding gun adopts L-shaped swing during the welding process; the welding foot height is about 8mm; the welding voltage is about 20V; the welding current is about 160A; the welding speed is about 0.9mm / s; the left and right swing width is about 4mm; the left and right dwell time are about 1.4s respectively; the middle dwell time is about 0.2s; the welding gun inclination angle is about 47°; Then, the four flat joints at the bottom plate are continuously welded in a continuous arc manner, that is, the four flat joints at the bottom plate form non-interrupted continuous welding in the surrounding directions, and finally form fillet welds; The specific process used by the welding robot for continuous welding of flat joints is: using mixed gas, three-layer six-pass flat welding to complete the welding; the weld foot height is about 16mm; the welding voltage is about 28V; the welding current is about 280A; the welding speed is about 5mm / s; the welding gun inclination angle is about 43°; Compared with the welding process of the flat joint, the welding process of the vertical joint can effectively prevent the gravity drop of the welding water, so as to reliably ensure the welding forming quality of the vertical weld. Step 5. According to the designed structure, spot weld the top plate onto each longitudinal rib and each transverse rib; Step 6. Turn the relative positions of the bottom plate and the top plate on the work platform so that the top plate is facing downward and the bottom plate is facing upward; Spot weld the turned structure to the supporting fixture on the working platform; Step 7. Repeat step 4; The mechanical arm of the welding robot extends from the bottom side pouring port of the bottom plate into the current pouring cavity, and continuously welds four flat joints at the top plate in the current pouring cavity in a continuous arc manner (compared to step 4 as a whole, there is no welding of vertical joints), completing automatic welding; Step 8. Perform quality inspection on the welded grid. The specific technical standard for quality inspection is to use magnetic particle inspection. The magnetic particle inspection (MT) inspection should comply with the provisions of GB / T 26952-2011 Level 1. Step 9. The grilles that have passed the quality inspection will be transferred to the heat treatment process and the finishing process in sequence until they are finished products.

[0064] The above embodiments are only used to illustrate the present invention, but not to limit it.

[0065] Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the above embodiments or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not deviate the essence of the corresponding technical solutions from the spirit and scope of the present invention.

Claims

1. A grid structure for a suspension bridge, comprising a bottom plate (1), a top plate (2), a plurality of longitudinal ribs (3) and a plurality of transverse ribs (4); A plurality of longitudinal ribs (3) are arranged between the bottom plate (1) and the top plate (2) at intervals along the transverse direction of the bridge, and each longitudinal rib (3) is arranged vertically along the direction of the bridge; The plurality of transverse ribs (4) are divided into a plurality of groups, and the plurality of transverse ribs (4) in each group are arranged along the longitudinal direction of the bridge in each longitudinal channel between the bottom plate (1) and the top plate (2), and each transverse rib (4) is arranged vertically in the transverse direction of the bridge; Adjacent longitudinal ribs (3) and adjacent transverse ribs (4) between the bottom plate (1) and the top plate (2) enclose a casting cavity (5); the bottom plate (1) has a bottom casting port connected to each casting cavity (5) and having a smaller outline than the corresponding casting cavity (5); the top plate (2) has a top casting port connected to each casting cavity (5) and having a smaller outline than the corresponding casting cavity (5); Features: The longitudinal ribs (3) that enclose the casting cavity (5) respectively form continuous welds with the bottom plate (1), the top plate (2) and the transverse ribs (4), and the transverse ribs (4) respectively form continuous welds with the bottom plate (1) and the top plate (2).

2. The grid structure for a suspension bridge according to claim 1, characterized in that: The top pouring port contour structure on the top plate (2) is equal to the bottom pouring port contour structure on the bottom plate (1).

3. The grid structure for a suspension bridge according to claim 1 or 2, characterized in that: The top side pouring opening on the top plate (2) has a width of 280 to 505 mm in the direction along the adjacent longitudinal ribs; The top side pouring opening on the top plate (2) has a length of 265 to 305 mm in the direction along the adjacent transverse ribs.

4. The grid structure for a suspension bridge according to claim 1 or 2, characterized in that: The bottom side pouring opening on the bottom plate (1) has a width of 280 to 505 mm in the direction along the adjacent longitudinal ribs; The length of the bottom side pouring opening on the bottom plate (1) along the direction of adjacent transverse ribs is 265 to 305 mm.

5. The grid structure for a suspension bridge according to claim 1, characterized in that: The casting cavity (5) has a width of 490 to 645 mm in the direction along adjacent longitudinal ribs; The casting cavity (5) has a length of 395 to 420 mm in the direction along adjacent transverse ribs; The casting cavity (5) has a height of 420 to 450 mm in the direction along the bottom plate (1) and the top plate (2).

6. A method for forming a lattice structure for a suspension bridge according to any one of claims 1 to 5, characterized in that: The molding method comprises the following process steps: Step 1. According to the design structure, establish a theoretical 3D model that can be imported into the welding robot; The steel plate is cut and blanked to obtain a bottom plate, a top plate, a plurality of longitudinal ribs and a plurality of transverse ribs; Step 2. Arrange a plurality of longitudinal ribs and a plurality of transverse ribs vertically and horizontally on the bottom plate in an upright manner according to the designed structure, and assemble them by spot welding; Secure the assembled structure to the work platform; Step 3. Import the theoretical 3D model into the welding robot; Step 4. The welding robot performs a global visual scan of the assembled structure through a global visual system to obtain a scanned 3D cloud image, and globally matches the 3D cloud image with the theoretical 3D model. After the matching is completed, a welding task is generated according to the set welding sequence; When the welding robot automatically welds the joint seams in each casting cavity, the robot arm extends into the current casting cavity from the open area surrounded by the transverse ribs and the longitudinal ribs, and first welds the four vertical joint seams between the transverse ribs and the longitudinal ribs in sequence to form fillet welds; Then, four flat joints at the bottom plate are welded continuously in a continuous arc manner to form fillet welds; Step 5. According to the designed structure, spot weld the top plate onto each longitudinal rib and each transverse rib; Step 6. Turn the relative positions of the bottom plate and the top plate on the work platform so that the top plate is facing downward and the bottom plate is facing upward; Fix the turned structure on the working platform; Step 7. Repeat step 4; When the welding robot automatically welds the joint seams in each casting cavity, the robot arm extends from the casting port on the bottom side of the bottom plate into the current casting cavity, and continuously welds the four flat joint seams at the top plate in the current casting cavity in a continuous arc manner to complete the automatic welding; Step 8. Perform quality inspection on the welded grid; Step 9. The grilles that have passed the quality inspection will be transferred to the heat treatment process and the finishing process in sequence until they become the finished product.

7. The method for forming a lattice structure for a suspension bridge according to claim 6, characterized in that: There are two welding robots arranged at the working platform, and the two welding robots are arranged at both longitudinal sides of the grid assembly structure; Correspondingly, the welding sequence followed by the welding robot in step 4 is: Taking the top plane of the grid assembly structure as a reference, the area where each casting cavity of the grid assembly structure is located is divided into four quadrants along the longitudinal axis of the grid assembly structure and the transverse axis of the grid assembly structure. The operating range of each welding robot corresponds to each casting cavity in a quadrant of the current diagonal distribution. The two welding robots perform the welding sequence of each casting cavity in the current corresponding quadrant synchronously; Each welding robot takes the casting cavity at the origin as the starting point for each casting cavity distributed in the current corresponding quadrant, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded; then, the next horizontal column between the welded horizontal columns is taken as the welding object area, and takes the casting cavity at the vertical axis as the starting point, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the selected horizontal column are welded; and so on.

8. The method for forming a grid structure for a suspension bridge according to claim 6, characterized in that: There are four welding robots arranged at the working platform. These four welding robots are arranged on both sides of the grid assembly structure in the longitudinal direction, with two on each side. Correspondingly, the welding sequence followed by the welding robot in step 4 is: Taking the top plane of the grid assembly structure as a reference, the area where each casting cavity of the grid assembly structure is located is divided into four quadrants along the longitudinal axis of the grid assembly structure and the transverse axis of the grid assembly structure. The operating range of each welding robot corresponds to each casting cavity in a quadrant. The welding robots corresponding to the two diagonally distributed quadrants perform the welding sequence of each casting cavity in the diagonal quadrant synchronously; Each welding robot takes the casting cavity at the origin as the starting point for each casting cavity distributed in the current corresponding quadrant, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the current horizontal column are welded; then, the next horizontal column between the welded horizontal columns is taken as the welding object area, and takes the casting cavity at the vertical axis as the starting point, and performs automatic welding operations in sequence along the horizontal axis until all the casting cavities in the selected horizontal column are welded; and so on.

9. The method for forming a grid structure for a suspension bridge according to claim 6, characterized in that: In step 4, the welding robot uses mixed gas and flat welding to complete welding of the flat joint; The specific welding process is: weld foot height ≥5mm; welding voltage 28~32V; welding current 240~300A; welding speed 4~6mm / s; welding gun inclination angle 30~50°.

10. The method for forming a grid structure for a suspension bridge according to claim 6, characterized in that: In step 4, the welding robot uses mixed gas and vertical welding to complete the welding of the vertical joint, and the welding gun uses L-shaped swing during the welding process; The specific welding process is: weld foot height ≥5mm; welding voltage 16~21V; welding current 130~180A; welding speed 0.7~1mm / s; left and right swing width 2~7mm; left and right dwell time 1~1.5s respectively; middle dwell time 0.1~0.3s; welding gun inclination angle 40~60°.

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