Intelligent assembly and welding device for small-bore steel pipes and operation method thereof

Abstract

The application discloses a kind of small-bore steel pipe intelligent assembly welding device and operating method, including workbench, two feeding roller way being arranged in the both sides of workbench, door-shaped support;Coaxial fixed chuck and movable chuck are arranged on workbench, movable chuck is arranged on workbench by two guide rail pairs, movable chuck is fixedly connected with nut, main servo motor is arranged on workbench, and main servo motor is connected with screw rod matched with nut;Centering mechanism is arranged on the workbench between fixed chuck and movable chuck, and centering mechanism includes fixed base, two hydraulic chucks axially spaced apart on base, and positioning baffle hinged to base at one end, and three clamping jaws of two hydraulic chucks are connected with press wheel;Switching type multi-welding gun device is arranged on the crossbeam of door-shaped support;The application can automatically align steel pipe bevel and automatically select matched welding wire, realize the automatic assembly of small-bore pipe and automatic welding, improve small-bore pipe welding quality and welding efficiency, completely solve the influence of welder skill on welding quality, and improve small-bore pipe manufacturing efficiency and intelligent level.

Description

Technical Field

[0001] This invention relates to a small-diameter steel pipe welding device and its operating method, particularly a small-diameter steel pipe welding device and its operating method for power plant boilers. Background Technology

[0002] The power plant boiler uses a large number of small-diameter steel pipes, ranging in size from φ31.8 to 89 mm and wall thickness from δ3.5 to 22 mm, with materials covering carbon steel, heat-resistant steel, and stainless steel. The butt welding of small-diameter pipes is mainly completed using hot-wire TIG welding or manual tungsten inert gas welding. Hot-wire TIG welding requires manual operation; during the pipe splicing process, one welder is always needed to manually perform tasks such as loading the pipe, assembling the pipe ends, manually purging argon, igniting the welding arc, adjusting welding parameters in real time, and manually labeling the weld. This results in the following two shortcomings:

[0003] (1) Insufficient level of intelligence

[0004] Before butt welding of steel pipes, a large number of tedious manual operations are required, such as aligning the bevels, filling the pipes with argon gas, manually striking the arc, fine-tuning the welding parameters, and using a variety of different welding wires, because the steel pipes involve different sizes and materials. During the welding process, the welder also needs to monitor the arc and the weld formation.

[0005] (2) Unstable welding quality

[0006] Welding quality is often affected by the welder's operating habits, skill level, sense of responsibility and emotions. In addition, the welding parameters used in the welding process are not the same, and the welder's pass rate varies and fluctuates, resulting in unstable weld quality. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned shortcomings of the prior art by providing an intelligent welding device and operating method for small-diameter steel pipes. This device can automatically align the bevel of the steel pipe and automatically select the matching welding wire, thereby achieving automatic assembly and welding of small-diameter pipes, improving the welding quality and efficiency of small-diameter pipes, completely eliminating the influence of welder skills on welding quality, and enhancing the manufacturing efficiency and intelligence level of small-diameter pipes.

[0008] To achieve the above objectives, the present invention provides an intelligent welding device for small-diameter steel pipes, comprising a worktable, two feeding roller conveyors located on both sides of the worktable, and a portal frame fixed to the worktable; characterized in that: a fixed chuck and a movable chuck are coaxially arranged on the worktable, the movable chuck is mounted on the worktable via two guide rail pairs, the movable chuck is fixedly connected to a nut, a main servo motor is provided on the worktable, the main servo motor is connected to a lead screw that cooperates with the nut; a centering mechanism is provided on the worktable between the fixed chuck and the movable chuck, the centering mechanism comprising a base fixed to the worktable, two hydraulic chucks spaced axially on the base along the fixed chuck and the movable chuck, and a positioning baffle with one end hinged to the base, the positioning baffle being located axially between the two hydraulic chucks, and the three jaws of the two hydraulic chucks are all... It is equipped with a pressure roller; the crossbeam of the portal frame is equipped with a switchable multi-welding gun device, including an X-axis lead screw mounted on the crossbeam via bearings at both ends, a lower nut cooperating with the X-axis lead screw, a movable slide plate fixedly connected to the lower nut, and an upper slide plate mounted on the movable slide plate via two Y-axis guide rail pairs. The movable slide plate is equipped with a Y-axis lead screw, and the upper slide plate is fixedly connected to an upper nut cooperating with the Y-axis lead screw. Both the X-axis lead screw and the Y-axis lead screw are connected to their respective servo motors. The upper slide plate is fixedly equipped with two or more sets of mounting brackets and anti-rotation blocks. Each mounting bracket is equipped with a longitudinal lead screw via bearings. The upper end of each longitudinal lead screw is connected to a longitudinal servo motor, and the lower end of each longitudinal lead screw is connected to a nut sleeve. The anti-rotation block is placed in the longitudinal groove of the corresponding nut sleeve. The lower end of each nut sleeve is connected to an argon arc welding gun and a wire feeding tube. Each wire feeding tube contains a different type of welding wire.

[0009] The present invention discloses an operating method for an intelligent welding device for small-diameter steel pipes, comprising the following steps: A) placing two steel pipes to be welded on the feeding roller conveyors on both sides respectively; B) flipping the positioning baffle so that it is engaged between the two hydraulic chucks; C) pushing the steel pipes on both sides into position, passing them through the fixed chuck or the movable chuck respectively, with the bevel ends of both steel pipes contacting the positioning baffle, and the fixed chuck and the movable chuck clamping their respective steel pipes; D) flipping the positioning baffle back to its original position, and simultaneously activating the two hydraulic chucks to release the steel pipes, clamping their respective steel pipes through three pressure rollers for initial centering, and then fixing them. E) The chuck and the moving chuck clamp their respective steel pipes again; F) The three pressure rollers of the hydraulic chuck adjacent to the moving chuck are manipulated to release the steel pipe, and the moving chuck is moved forward by the main servo motor, lead screw and nut, so that the bevel ends of the two steel pipes are close together, and the three pressure rollers of the hydraulic chuck adjacent to the moving chuck clamp the steel pipe again; G) The argon arc welding gun with the given welding wire grade is selected by the two servo motors and the longitudinal servo motor and moved to the welding position at the bevel ends of the two steel pipes, and the two steel pipes are rotated to achieve welding; G) After welding, the three pressure rollers of the fixed chuck, the moving chuck and the two hydraulic chucks release the steel pipe and remove the steel pipe;

[0010] The two steel pipe bevels typically adopt a U-shaped bevel. The pairing of the two steel pipe bevels is achieved by a centering mechanism. Each of the three jaws of the two hydraulic chucks is connected to three pressure rollers. The three pressure rollers contact the steel pipe at three points to achieve clamping of the steel pipe. This invention utilizes the fact that the steel pipe bevel is processed based on the outer wall of the steel pipe. Therefore, the center of the processed steel pipe bevel is concentric with the center of the outer wall of the steel pipe. That is, the steel pipe bevel can be automatically aligned by centering the steel pipe. The small-diameter pipes of power plant boilers are quite long and involve different materials and outer diameters. By clamping the steel pipe multiple times with the three pressure rollers of the fixed chuck, the moving chuck, and the two hydraulic chucks, the influence of the placement and deflection deformation of the steel pipe on the automatic alignment of the steel pipe bevel can be eliminated. At the same time, the position of the welding torch can be arbitrarily adjusted within the steel pipe bevel, and the matching welding wire can be automatically selected to achieve automatic pairing and automatic welding of small-diameter pipes. This improves the welding quality and efficiency of small-diameter pipes, completely solves the influence of welder skills on welding quality, and improves the manufacturing efficiency and intelligence level of small-diameter pipes.

[0011] As a further improvement of the present invention, the workbench is provided with four adjustable legs; correspondingly, in step C), for steel pipes of different outer diameters, the height of the workbench is adjusted by the four adjustable legs so that the axis of the steel pipes on both sides is at the same height as the axis of the fixed chuck and the movable chuck; this is applicable to the assembly welding of steel pipes of different outer diameters.

[0012] As a further improvement of the present invention, a proximity switch is provided at the other end of the positioning baffle; correspondingly, in step B), the proximity switch at the other end of the positioning baffle is used to detect that it has flipped into place; this can improve the level of intelligence.

[0013] In summary, this invention can automatically align the bevel of steel pipes and automatically select matching welding wires, realizing automatic assembly and welding of small-diameter pipes, improving the welding quality and efficiency of small-diameter pipes, completely solving the impact of welder skills on welding quality, and enhancing the manufacturing efficiency and intelligence level of small-diameter pipes. Attached Figure Description

[0014] Figure 1 This is a simplified structural diagram of an embodiment of the intelligent welding device for small-diameter steel pipes of the present invention.

[0015] Figure 2 for Figure 1 Enlarged view of the centering mechanism.

[0016] Figure 3 for Figure 2 The right view.

[0017] Figure 4 for Figure 1 Front view of the switching multi-welding gun device.

[0018] Figure 5 for Figure 4 A partial top view.

[0019] Figure 6 for Figure 4 Partial left view Detailed Implementation

[0020] The invention will be further described below with reference to the accompanying drawings.

[0021] like Figures 1 to 6 As shown, this embodiment of an intelligent welding device for small-diameter steel pipes includes a worktable 1 with four liftable bed legs 4, two feeding roller conveyors 2 on both sides of the worktable, and a portal frame 3 fixed on the worktable 1; a fixed chuck 5 and a movable chuck 6 are coaxially arranged on the worktable 1, the movable chuck 6 is mounted on the worktable 1 via two guide rail pairs 7, and a nut is fixedly connected to the movable chuck 6; a main servo motor 8 is provided on the worktable 1, and the main servo motor 8 is connected to a lead screw 9 that cooperates with the nut; the fixed chuck... A centering mechanism 10 is provided on the worktable between the fixed chuck 5 and the movable chuck 6. The centering mechanism 10 includes a base 11 fixed on the worktable, two hydraulic chucks 12 spaced apart on the base 11 along the axial direction of the fixed chuck 5 and the movable chuck 6, and a positioning baffle 15 hinged to the base at one end. A proximity switch 16 is provided at the other end of the positioning baffle 15. The positioning baffle 15 is located axially between the two hydraulic chucks 12. Each of the three jaws 13 of the two hydraulic chucks 12 is connected to a pressure roller 14. A portal frame 3 is also provided. A switching multi-welding gun device 17 is provided on the crossbeam. The switching multi-welding gun device 17 includes an X-direction lead screw 18 mounted on the crossbeam via bearings at both ends, a lower nut 19 cooperating with the X-direction lead screw 18, a movable slide plate 21 fixedly connected to the lower nut 19, and an upper slide plate 23 mounted on the movable slide plate 21 via two Y-direction guide rail pairs 22. The X-direction lead screw 18 is connected to a servo motor 24. A Y-direction lead screw 25 is provided on the movable slide plate 21, and an upper nut cooperating with the Y-direction lead screw 25 is fixedly connected to the upper slide plate 23. The Y-axis lead screw 25 is connected to the servo motor 26; the upper slide plate 23 is fixed with three sets of mounting brackets 27 and anti-rotation blocks 28. Each mounting bracket 27 is equipped with a longitudinal lead screw 29 through bearings. The upper end of each longitudinal lead screw 29 is connected to a longitudinal servo motor 30, and the lower end of each longitudinal lead screw 29 is connected to a nut sleeve 31 through a thread. The anti-rotation block 28 is placed in the longitudinal groove of the corresponding nut sleeve 31. The lower end of each nut sleeve 21 is connected to an argon arc welding gun 32 and a wire feeding tube (not shown). Each wire feeding tube contains a different type of welding wire.

[0022] The present invention provides an operating method for a small-diameter steel pipe intelligent welding device for the aforementioned intelligent welding apparatus, comprising the following steps: A) placing two steel pipes 33 to be welded on the feeding roller conveyors 2 on both sides respectively; B) flipping the positioning baffle 15 so that it is engaged between the two hydraulic chucks 12, and detecting its engagement through the proximity switch 16 at its other end; C) adjusting the height of the worktable 1 by the four liftable bed legs 4 so that the axis of the steel pipes 33 on both sides is at the same height as the axis of the fixed chuck 5 and the movable chuck 6, pushing the steel pipes 33 on both sides into place, passing through the fixed chuck 5 or the movable chuck 6 respectively, with the bevel ends of the two steel pipes 33 contacting the adjacent end faces of the positioning baffle 15, and clamping their respective steel pipes 33 by the fixed chuck 5 and the movable chuck 6 to perform initial positioning of the steel pipe axis; D) flipping the positioning baffle 15 back to its original position, and releasing the steel pipes 33 from the fixed chuck 5 and the movable chuck 6. A) Start the two hydraulic chucks 12, clamp the steel pipes 33 with three pressure rollers 14 for initial centering, and then the fixed chuck 5 and the movable chuck 6 clamp the steel pipes 33 again; B) Operate the three pressure rollers 14 of the hydraulic chuck 12 adjacent to the movable chuck 6 to release the steel pipes 33, and drive the movable chuck 6 forward through the main servo motor 8, lead screw 9 and nut, so that the bevel ends of the two steel pipes 33 are close, and the three pressure rollers 14 of the hydraulic chuck 12 clamp the steel pipes 33 again to complete the final centering; C) Use the two servo motors 24, 26 and the longitudinal servo motor 30 to move the argon arc welding gun 32 with the given welding wire grade to the welding position of the bevel ends of the two steel pipes, and rotate the two steel pipes 33 through the fixed chuck 5 and the movable chuck 6 to achieve welding; D) After welding, the fixed chuck 5, the movable chuck 6 and the three pressure rollers 14 of the two hydraulic chucks 12 release the steel pipes 33 and remove the steel pipes;

[0023] The bevels of the two steel pipes 33 are typically U-shaped bevels. The alignment of the two steel pipe bevels is achieved by a centering mechanism 10: each of the three jaws 13 of the two hydraulic chucks 12 is connected to a pressure roller 14. The three pressure rollers 14 contact the steel pipe 33 at three points to achieve clamping of the steel pipe 33. This invention utilizes the fact that the steel pipe bevel processing is based on the outer wall of the steel pipe; therefore, the center of the processed steel pipe bevel is concentric with the center of the outer wall of the steel pipe. That is, the steel pipe bevels can be automatically aligned through steel pipe centering. The small-diameter pipes of power plant boilers are quite long and involve different materials and outer diameters. Through fixing... The three pressure rollers 14 of the fixed chuck 5, the movable chuck 6, and the two hydraulic chucks 12 clamp the steel pipe 33 multiple times, which can eliminate the influence of the placement and deflection deformation of the steel pipe on the automatic alignment of the steel pipe bevel. At the same time, it can realize the arbitrary adjustment of the welding torch position within the steel pipe bevel, and automatically select different types of welding wire to realize the automatic assembly and welding of small diameter pipes. It can be used for steel pipes of different materials and outer diameters, which can improve the welding quality and welding efficiency of small diameter pipes, completely solve the influence of welder skills on welding quality, and improve the manufacturing efficiency and intelligence level of small diameter pipes.

[0024] The height of the worktable 1 can be adjusted by four adjustable bed legs 4, which can be used for welding steel pipes with different outer diameters.

[0025] The level of intelligence can be improved by detecting the rotation of the positioning baffle 15 into position by the proximity switch 16.

[0026] The above embodiments have been used to illustrate the invention, but it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit the invention to the scope of the described embodiments.

Claims

1. A method for operating a small-diameter steel pipe intelligent welding device, the device comprising a worktable, two feeding roller conveyors on both sides of the worktable, and a portal frame fixed to the worktable; a fixed chuck and a movable chuck are coaxially arranged on the worktable, the movable chuck is mounted on the worktable via two guide rails, and a nut is fixedly connected to the movable chuck; a main servo motor is provided on the worktable, and the main servo motor is connected to a lead screw that cooperates with the nut; a centering mechanism is provided on the worktable between the fixed chuck and the movable chuck, the centering mechanism comprising a base fixed to the worktable, two hydraulic chucks spaced axially on the base along the fixed chuck and the movable chuck, and a positioning baffle hinged to the base at one end, the positioning baffle being axially located between the two hydraulic chucks, and each of the three jaws of the two hydraulic chucks being connected to a pressure roller; comprising the following steps: A) Place the two steel pipes to be welded on the feeding roller conveyors on both sides respectively; characterized in that: B) Flip the positioning baffle so that it is locked between the two hydraulic chucks; C) Push the steel pipes on both sides into place, passing them through the fixed chuck or the movable chuck respectively, with the bevel ends of both steel pipes contacting the positioning baffle, and the fixed chuck and the movable chuck clamping their respective steel pipes; D) Flip the positioning baffle back to its original position, and while the fixed chuck and the movable chuck release the steel pipes, activate the two hydraulic chucks to clamp their respective steel pipes through the three pressure rollers for initial centering, and then the fixed chuck and the movable chuck clamp their respective steel pipes again. E) The three pressure rollers of the hydraulic chuck adjacent to the moving chuck loosen the steel pipe, and the moving chuck is moved forward by the main servo motor, lead screw and nut, so that the bevel ends of the two steel pipes are close together, and the three pressure rollers of the hydraulic chuck adjacent to the moving chuck clamp the steel pipe again; F) The argon arc welding gun of the given welding wire grade is selected by the two servo motors and the longitudinal servo motor and moved to the welding position of the bevel ends of the two steel pipes, and the two steel pipes are rotated to achieve welding; G) After welding, the three pressure rollers of the fixed chuck, the moving chuck and the two hydraulic chucks loosen the steel pipe and remove the steel pipe.

2. The operating method of the intelligent welding device for small-diameter steel pipes as described in claim 1, characterized in that: The crossbeam of the portal frame is equipped with a switchable multi-welding gun device, including an X-axis lead screw mounted on the crossbeam via bearings at both ends, a lower nut cooperating with the X-axis lead screw, a movable slide plate fixedly connected to the lower nut, and an upper slide plate mounted on the movable slide plate via two Y-axis guide rails. The movable slide plate is equipped with a Y-axis lead screw, and the upper slide plate is fixedly connected to an upper nut cooperating with the Y-axis lead screw. Both the X-axis lead screw and the Y-axis lead screw are connected to their respective servo motors. The upper slide plate is fixedly equipped with two or more sets of mounting brackets and anti-rotation blocks. Each mounting bracket is equipped with a longitudinal lead screw via bearings. The upper end of each longitudinal lead screw is connected to a longitudinal servo motor, and the lower end of each longitudinal lead screw is connected to a nut sleeve. The anti-rotation block is placed in the longitudinal groove of the corresponding nut sleeve. The lower end of each nut sleeve is connected to an argon arc welding gun and a wire feeding tube, and each wire feeding tube contains welding wire.

3. The operating method of the intelligent welding device for small-diameter steel pipes as described in claim 1 or 2, characterized in that: The workbench is equipped with four adjustable legs; in step C), for steel pipes of different outer diameters, the height of the workbench is adjusted by the four adjustable legs so that the axis of the steel pipes on both sides is at the same height as the axis of the fixed chuck and the movable chuck.

4. The operating method of the intelligent welding device for small-diameter steel pipes as described in claim 1 or 2, characterized in that: The other end of the positioning baffle is provided with a proximity switch; in step B), the proximity switch at the other end of the positioning baffle is used to detect that it has flipped into place.

Images