Manipulator for automatic welding of heat exchangers

Abstract

This invention relates to the field of welding robots, and more specifically, to an automatic welding robot for heat exchangers, comprising: a robot body; a welding frame fixedly mounted on one side of the drive head at the power end of the robot body; a welding assembly mounted on one side of the welding frame for welding the heat exchanger; and a baffle mounted on the side wall of the welding assembly near the welding frame. In this invention, parameters can be individually adjusted for welds in different locations to enhance process adaptability. The extension tube can extend the axial working distance, adapting to welding in narrow spaces, and can be replaced individually after damage, reducing maintenance costs. It prevents the baffle from shifting due to airflow impact or vibration, avoids long-term high-temperature deformation, extends the slag travel path, and allows the slag to settle after multiple collisions and deceleration. The arc-shaped plate at the front end of the baffle can guide the slag flow in the correct direction, preventing spatter. Overall, it reduces the burning damage of high-temperature slag to transmission and sealing components, extending equipment life.

Description

Technical Field

[0001] This invention relates to the field of welding robots, and more specifically, to a robot for automatically welding heat exchangers. Background Technology

[0002] Heat exchangers are energy-saving devices that transfer heat between two or more fluids at different temperatures to meet process requirements such as heating, cooling, and condensation, thereby improving energy utilization. During the production and processing of heat exchangers, automated welding robots are typically used because heat exchangers have numerous and densely arranged welding stations for tube sheets, U-tubes, and other components. Traditional manual welding is inefficient and produces inconsistent quality. Automated welding robots, however, can achieve high-precision trajectory control through multi-axis linkage, improving welding efficiency, reducing worker labor intensity, and ensuring uniform and stable weld formation. They are suitable for welding various materials such as carbon steel, stainless steel, and titanium alloys. Furthermore, they typically employ a multi-head design to allow multiple welding heads to operate simultaneously in dense pipe welding scenarios, completing multiple weld points at once. Compared to a single-head welding mode, this reduces overall welding time, making them particularly suitable for batch welding of hundreds or thousands of heat exchange tubes on heat exchangers. Simultaneous control ensures uniform process parameters for all welds, further improving the overall welding quality consistency of the heat exchanger and avoiding the accumulation of errors and efficiency losses caused by repeated positioning of a single welding head.

[0003] Chinese patent publication number 201820353892.7 discloses an automatic welding truss robot, characterized by: a workbench, a power cabinet, a welding device, and a base; the power cabinet and a fixed support are located above the base; a wheel is located on one side of the power cabinet, and the welding device is located on the fixed support; a fixed support is located above the workbench, and a support foot is located below the fixed support; a spiral support is located on one side of the power cabinet; a robotic arm is located on the spiral support; the support frame is mainly composed of support connecting rods; the automatic welding truss robot of this utility model has a fumigation device located on one side of the welding device, the fumigation device has a ventilation pipe, the ventilation pipe is connected to the base, and the workbench has an automatic folding light shield, one side of which is connected to a small cylinder inside the base. The combination of the fumigation device and the automatic folding light shield can reduce the harm to workers caused by welding fumes and strong light.

[0004] However, existing technologies have the following problems when in use: current robotic arm welding heads are mostly single-path welding structures, resulting in low welding efficiency, and each weld seam cannot independently adjust process parameters, leading to poor process adaptability; the welding head extension structure is inconvenient to disassemble and assemble, and structural interference is prone to occur when operating in narrow spaces, and the spacing between multiple welding heads is easily affected by vibration, resulting in poor weld seam formation consistency; the slag protection structure is of a single form, the baffle has poor heat dissipation performance, and it is prone to deformation during long-term high-temperature operation, and the slag can easily penetrate the baffle and splash onto the precision components behind, causing burns to the transmission and sealing components and shortening the service life of the equipment. In order to solve the above problems, a robotic arm for automatically welding heat exchangers is proposed. Summary of the Invention

[0005] Technical problems to be solved To address the problems existing in the prior art, this invention provides a robotic arm for an automatic welding heat exchanger, which solves the problems mentioned in the background art, such as low welding efficiency, inability to independently adjust process parameters for each weld, poor process adaptability, inconvenient disassembly and assembly of the welding head extension structure, easy structural interference in narrow space operations, easy displacement of the spacing between multiple welding heads due to vibration, poor weld formation consistency, single form of slag protection structure, poor heat dissipation performance of the baffle, easy deformation under long-term high-temperature operation, and easy slag penetration of the baffle to splash onto the precision components behind, causing burns to transmission and sealing components and shortening the service life of the equipment.

[0006] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: a robotic arm for automatically welding heat exchangers, comprising... Robotic arm body; The welding frame is fixedly installed on one side of the drive head at the power end of the robot body; The welding assembly, located on one side of the welding frame, is used for welding the heat exchanger; A baffle is installed on the side wall of the welding assembly near the welding frame. The inner cavity of the baffle is provided with multiple sets of inclined plates, which are evenly distributed along the length of the inner cavity of the baffle. A channel for air flow is provided between every two inclined plates. An arc-shaped plate is fixedly connected to one side of each inclined plate. An isolation space is provided between the arc-shaped plate and the baffle to prevent welding slag from splashing.

[0007] The invention is further configured such that the welding assembly includes regulating valves, and there are at least seven sets of regulating valves, which are evenly distributed along the length of the welding frame.

[0008] The present invention is further configured such that a mounting base is provided at the end of the regulating valve, and an extension tube is threadedly connected to one end of the mounting base.

[0009] The present invention is further configured such that a welding head is fixedly connected to the end of the extension tube.

[0010] The present invention is further configured such that a positioning plate is provided between the multiple sets of the extension tubes.

[0011] The invention is further configured such that the side wall of the welding frame is provided with a connecting pipe, and the connecting pipe is connected to multiple sets of regulating valves.

[0012] The present invention is further configured such that one end of the connecting pipe is connected to an external gas storage tank.

[0013] The present invention is further configured such that a support plate is fixedly connected between the outer sides of the plurality of regulating valves, and the baffle is fixedly connected to one side of the support plate.

[0014] The present invention is further configured such that the tilt angle of the tilting plate is from 100 degrees to 100 degrees.

[0015] The present invention is further configured such that a base is provided at the bottom of the main body of the robotic arm.

[0016] (III) Beneficial Effects Compared with the prior art, the present invention provides a robotic arm for automatically welding heat exchangers, which has the following advantages: 1. This invention relies on a multi-axis, multi-joint robotic arm body in conjunction with a servo rotary drive head. Multi-degree-of-freedom spatial motion drives the end welding structure to complete full-space weld alignment. Multiple sets of independent regulating valves evenly arranged along the welding frame can individually control the protective gas flow of each branch. Combined with threaded extension tubes, the welding medium is conducted to the welding head. This allows for simultaneous welding of multiple weld seams, improving processing efficiency, and also enables individual parameter adjustments for weld seams in different locations, enhancing process adaptability. The extension tubes extend the axial working distance, adapting to welding in narrow spaces, and can be replaced individually if damaged, reducing maintenance costs. The positioning plate radially limits multiple extension tubes through through holes, preventing them from shifting due to airflow impact or vibration, ensuring the welding head spacing accuracy and coaxiality, and improving weld formation consistency.

[0017] 2. This invention, by setting multiple sets of inclined plates in the inner cavity of the baffle, with adjacent plates and the inner wall forming an inclined channel, allows air circulation to carry away welding heat, achieving air cooling and preventing long-term high-temperature deformation of the baffle; it can extend the path of welding slag, causing the welding slag to settle after multiple collisions and deceleration, preventing it from splashing to the precision parts behind; the arc-shaped plate at the front end of the baffle can guide the flow of welding slag in the forward direction, avoiding splashing; the isolation space between the plates forms an air insulation layer, reducing heat conduction and guiding the welding slag to slide off; overall, it can reduce the burning damage of high-temperature welding slag to transmission and sealing components, and extend the service life of the equipment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the robotic arm used for automatic welding heat exchangers.

[0019] Figure 2This is a first-person view structural diagram of the welding frame of a robotic arm for an automated welding heat exchanger.

[0020] Figure 3 This is a second-view structural diagram of the welding frame of a robotic arm for an automated welding heat exchanger.

[0021] Figure 4 A schematic diagram of the baffle structure of the robotic arm for an automated welding heat exchanger.

[0022] Figure 5 This is a cross-sectional view of the baffle structure of the robotic arm for an automated welding heat exchanger.

[0023] Figure 6 Robotic arms for automated welding heat exchangers Figure 5 Enlarged diagram of point A in the middle.

[0024] In the diagram: 100, main body of the robotic arm; 110, base; 120, drive head; 130, welding frame; 131, connecting pipe; 140, regulating valve; 141, mounting base; 150, support plate; 151, baffle; 152, inclined plate; 153, arc plate; 154, isolation space; 155, channel; 160, extension pipe; 161, welding head; 162, positioning plate. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0027] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0028] For examples, please refer to Figures 1-6 A robotic arm for automatically welding heat exchangers, including The main body of the robotic arm is 100. The welding frame 130 is fixedly installed on one side of the drive head 120 at the power end of the robot body 100; A welding assembly, located on one side of the welding frame 130, is used for welding the heat exchanger; A baffle 151 is disposed on the side wall of the welding assembly near the welding frame 130. Multiple sets of inclined plates 152 are inclinedly arranged in the inner cavity of the baffle 151. The multiple sets of inclined plates 152 are evenly distributed along the length of the inner cavity of the baffle 151. A channel 155 for air flow is provided between every two inclined plates 152. An arc plate 153 is fixedly connected to one side of each inclined plate 152. An isolation space 154 is provided between the arc plate 153 and the baffle 151 to prevent welding slag spatter.

[0029] In this application, the main body 100 of the robot arm can adopt a multi-axis, multi-joint industrial robot arm structure, which has at least three spatial motion degrees of freedom. It can drive the end working structure to complete the weld alignment and continuous welding movement at any position and angle in space. The power end of the main body 100 of the robot arm is provided with a drive head 120, which can be a servo rotary drive head, capable of outputting controllable rotational torque to adjust the working posture of the end welding structure and adapt to the weld processing requirements of different orientations and tilt angles of the heat exchanger.

[0030] The welding frame 130 can be made of aluminum alloy profiles. Its connection end with the drive head 120 is detachably fixed by bolt locking. The welding frame 130 can rotate synchronously with the drive head 120, flexibly adjusting the orientation of the welding operation.

[0031] The welding assembly can be a gas shielded welding unit, which can move synchronously with the robot body 100 under the drive of the welding frame 130 and complete continuous welding processing along the preset weld seam trajectory; the overall arrangement direction of the welding assembly can be consistent with the length direction of the welding frame 130 to cover a longer weld seam processing range.

[0032] The baffle 151 can be made of high-temperature resistant chromium-nickel stainless steel plate. Its overall shape can be a long strip box structure that extends along the arrangement direction of the welding components. The baffle 151 can form a shielding barrier against the high-temperature welding slag that splashes towards the welding frame 130 during the welding operation, preventing the welding slag from directly splashing onto the precision mating surface of the welding frame 130 or the drive head 120, reducing the burn damage of high-temperature welding slag to the transmission components and sealing components, and extending the service life of the equipment.

[0033] The inclined plate 152 can be fixed piece by piece to the inner wall of the baffle 151 by spot welding. The plate surface of the inclined plate 152 can be a smooth plane. Multiple sets of evenly distributed inclined plates 152 can form an interception structure in the inner cavity of the baffle 151 to decelerate and intercept the welding slag passing through the baffle inlet step by step.

[0034] The channel 155 is formed by the combined enclosure of the surfaces of two adjacent inclined plates 152 and the inner wall of the baffle 151. Its flow cross section can be parallelogram-shaped. On the one hand, the channel 155 allows external air to form a flow path in the inner cavity of the baffle 151, using airflow to carry away the welding heat absorbed by the baffle, thereby achieving air cooling of the baffle 151 and the inclined plates 152, and avoiding deformation of the baffle or degradation of material properties due to long-term high-temperature operation. On the other hand, the inclined channel 155 can extend the passage path of the welding slag, causing the welding slag to collide with the inclined plates 152 multiple times in the channel, fully consuming kinetic energy and settling in the inner cavity of the baffle, preventing the welding slag from penetrating the baffle and splashing to the rear components.

[0035] The arc plate 153 can be made of the same high-temperature resistant material as the baffle 151. Its arc-shaped convex surface is set towards the welding operation area, and the arc curvature can be set according to the diffusion angle of welding spatter. The arc surface of the arc plate 153 can guide the welding slag that is spattered in the forward direction, guiding the welding slag to both sides and downwards, and preventing the welding slag from splashing after impacting the plate surface vertically. The isolation space 154 can form an air insulation layer between the arc plate 153 and the baffle 151, reducing the efficiency of the conduction of welding high temperature to the baffle side. At the same time, it can guide the welding slag that slides down the inner wall of the arc plate, preventing the welding slag from moving to the top of the channel 155.

[0036] In some examples of this application, the welding assembly includes regulating valves 140, which are at least seven in number and are evenly distributed along the length of the welding frame 130.

[0037] As a preferred example of the present invention, the regulating valve 140 can be a precision gas flow regulating valve. Each group of regulating valves 140 can independently adjust its opening degree to achieve independent control of the medium flow rate of the corresponding welding branch. The uniform arrangement of at least seven groups can simultaneously cover multiple parallel welds or long straight welds on the heat exchanger, realize multi-station synchronous welding operations, and improve the welding processing efficiency of the heat exchanger. At the same time, the independent adjustable setting of each group of regulating valves 140 can individually adjust the welding parameters according to the welding process requirements of different positions, adapt to the welding requirements of different parts and different wall thicknesses of the heat exchanger, and improve the process adaptability of the device.

[0038] In some examples of this application, the end of the regulating valve 140 is provided with a mounting base 141, and one end of the mounting base 141 is threadedly connected to an extension tube 160.

[0039] As a preferred example of the present invention, the mounting base 141 can be an internally threaded sleeve structure, which can be fixed to the outlet end of the regulating valve 140 by welding or by external thread screwing. The extension tube 160 is provided with a matching external thread section at one end near the mounting base 141, which can be screwed into the mounting base 141 to achieve a detachable sealed connection. The mounting base 141 provides a stable installation reference and sealing connection interface for the extension tube 160. The threaded connection method can facilitate the replacement of extension tubes 160 of different lengths and diameters according to the welding depth and weld avoidance requirements of the heat exchanger, thus broadening the applicable scenarios of the device. At the same time, when the extension tube is deformed, blocked or damaged, it can be disassembled and replaced separately without replacing the entire welding assembly, thus reducing equipment maintenance costs.

[0040] In some examples of this application, the end of the extension tube 160 is fixedly connected to a weld head 161.

[0041] As a preferred example of the present invention, the welding head 161 can be a combination of a gas shielded welding conductive nozzle and a protective gas nozzle, or a combination of an argon arc welding tungsten electrode clamp and a nozzle. It can be fixed and sealed to the end of the extension tube 160 by thread locking or by crimping. The extension tube 160 can conduct welding shielding gas, welding current and other media from the regulating valve 140 end to the welding head 161. At the same time, it can extend the axial working distance of the welding operation, which is convenient for welding operations to be carried out in narrow spaces such as tube sheet gaps and internal circumferential seams of the heat exchanger, and avoids structural interference between the welding frame 130 and the heat exchanger workpiece.

[0042] In some examples of this application, a positioning plate 162 is provided between multiple sets of extension tubes 160.

[0043] As a preferred example of the present invention, the positioning plate 162 can be a long strip of metal plate, with positioning through holes opened on the plate corresponding to the axial position of each group of extension tubes 160. The extension tubes 160 are inserted into the positioning through holes to achieve radial limiting. The positioning plate 162 can be set as one group, or multiple groups can be set at intervals along the axial direction of the extension tubes 160. The positioning plate 162 can fix the relative position of multiple extension tubes 160, so as to avoid the extension tubes from shaking or shifting due to airflow impact or mechanical vibration during the welding operation, and ensure the spacing accuracy and coaxiality of each group of welding heads 161, thereby improving the consistency and forming quality of multi-pass welding.

[0044] In some examples of this application, the side wall of the welding frame 130 is provided with a connecting pipe 131, which is connected to multiple sets of regulating valves 140.

[0045] As a preferred example of the present invention, the connecting pipe 131 can be a seamless stainless steel air pipe, which is fixedly laid along the length of the welding frame 130. The pipe body can be branched with air outlet joints corresponding to the positions of each group of regulating valves 140, and sealed and connected to the air inlet end of each group of regulating valves 140 respectively. The connecting pipe 131 can realize the uniform distribution of single-path air intake to multiple groups of regulating valves 140, simplify the air path layout of the welding assembly, reduce the number of external hoses, avoid multiple pipes entangled and interfering with the movement operation of the robot, and facilitate the overall inspection and maintenance of the air path.

[0046] In some examples of this application, one end of the connecting pipe 131 is connected to an external gas storage tank.

[0047] As a preferred example of the present invention, the external gas storage tank can be a high-pressure argon gas storage tank or a mixed protective gas storage tank of carbon dioxide and argon. It can be sealed to the gas inlet end of the connecting pipe 131 through a flexible high-pressure hose to provide a continuous and stable protective gas source for welding operations. Using an external gas storage tank for gas supply can ensure the stability of gas pressure and gas flow during welding, avoid the decrease in protective effect caused by gas supply pressure fluctuations, reduce welding defects such as weld oxidation and porosity, and improve weld formation quality.

[0048] In some examples of this application, a support plate 150 is fixedly connected between the outer sides of multiple sets of regulating valves 140, and a baffle 151 is fixedly connected to one side of the support plate 150.

[0049] As a preferred example of the present invention, the support plate 150 can be a long strip-shaped metal connecting plate. Its plate body can be locked and fixed to the outer wall of each group of regulating valves 140 by a clamp structure, or it can be fixedly connected to the outer wall of the regulating valves 140 by spot welding. The support plate 150 can form an outer structure reinforcement for multiple groups of parallel regulating valves 140, improve the overall vibration resistance and structural rigidity of the regulating valve group, and prevent the relative displacement of multiple groups of regulating valves during the high-speed movement of the robot arm. At the same time, the support plate 150 provides a stable mounting base for the baffle 151, so that the baffle 151 can be fixed at the corresponding protective position on the side of the welding assembly, ensuring the positional accuracy of the welding slag protection structure and the welding station, and ensuring the stability of the protection effect.

[0050] In some examples of this application, the tilt angle of the tilt plate 152 is 30 degrees to 60 degrees.

[0051] As a preferred example of the present invention, the inclined plate 152 can ensure that the channel 155 has sufficient airflow cross-sectional area to ensure the efficiency of air cooling, and can also make the spattered welding slag form a reasonable collision incident angle with the inclined plate surface, effectively consuming the flight kinetic energy of the welding slag and achieving efficient interception.

[0052] In some examples of this application, a base 110 is provided at the bottom of the robotic arm body 100.

[0053] As a preferred example of the present invention, the base 110 can be integrally cast from gray cast iron or welded from channel steel and steel plate. Multiple sets of mounting through holes can be opened at its bottom, and the robot arm can be fixed to the floor of the welding workshop or a special work platform by anchor bolts. The top surface of the base 110 and the base of the robot arm body 100 can be locked and fixed by bolts, or a slewing bearing structure can be added to realize the circumferential rotation adjustment of the robot arm. The base 110 can increase the bottom support area of ​​the robot arm, lower the center of gravity of the equipment, improve the overall stability of the machine during the welding operation, reduce the vibration amplitude during the start and stop of the robot arm, and ensure the alignment accuracy of the welding head 161 and the accuracy of the welding trajectory.

[0054] In practical use, the robotic arm body 100 supported by the base 110 performs multi-degree-of-freedom spatial motion, driving the drive head 120 at the power end to move to the welding position on the heat exchanger. The drive head 120 outputs rotational motion to drive the welding frame 130 to rotate, adjusting the working angle and orientation of the welding components. The protective gas is delivered from the external gas storage tank to the connecting pipe 131 on the side wall of the welding frame 130. After being split by the connecting pipe 131, the gas enters each group of regulating valves 140. After passing through the regulating valves 140, the gas enters the extension pipe 160 through the mounting base 141 and flows along the extension pipe. The heat exchanger is welded by conducting energy to the welding head 161 at the end and outputting to the weld area. During the welding process, the baffle 151 fixed on the outer support plate 150 of each group of regulating valves 140 moves synchronously with the welding frame 130. The spattered slag flows downward along the arc surface after contacting the arc plate 153. The isolation space 154 is located between the arc plate 153 and the baffle 151. Multiple extension tubes 160 are inserted into the corresponding through holes of the positioning plate 162 and move synchronously with the welding frame 130 to realize the welding of the heat exchanger.

[0055] Of all the solutions mentioned above, those involving the connection between two components can be selected according to the actual situation, such as welding, bolt and nut connection, bolt or screw connection, or other known connection methods, which will not be elaborated here. For all the fixed connections mentioned above, welding is preferred. Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A robotic arm for automatically welding heat exchangers, characterized in that: include Robotic arm body (100); The welding frame (130) is fixedly installed on one side of the drive head (120) at the power end of the robot body (100); A welding assembly, located on one side of the welding frame (130), is used for welding the heat exchanger; A baffle (151) is disposed on the side wall of the welding assembly near the welding frame (130). The inner cavity of the baffle (151) is provided with multiple sets of inclined plates (152). The multiple sets of inclined plates (152) are evenly distributed along the length of the inner cavity of the baffle (151). A channel (155) for airflow is provided between every two inclined plates (152). An arc plate (153) is fixedly connected to one side of each inclined plate (152). An isolation space (154) is provided between the arc plate (153) and the baffle (151) to prevent welding slag from splashing.

2. The robotic arm for automatically welding heat exchangers according to claim 1, characterized in that: The welding assembly includes regulating valves (140), which are at least seven in number and are evenly distributed along the length of the welding frame (130).

3. The robotic arm for automatically welding heat exchangers according to claim 2, characterized in that: The regulating valve (140) is provided with a mounting base (141) at its end, and an extension tube (160) is threaded to one end of the mounting base (141).

4. The robotic arm for automatically welding heat exchangers according to claim 3, characterized in that: The end of the extension tube (160) is fixedly connected to a welding head (161).

5. The robotic arm for automatically welding heat exchangers according to claim 4, characterized in that: A positioning plate (162) is provided between the multiple sets of the extension tubes (160).

6. The robotic arm for automatically welding heat exchangers according to claim 5, characterized in that: The welding frame (130) is provided with a connecting pipe (131) on its side wall, and the connecting pipe (131) is connected to multiple sets of regulating valves (140).

7. The robotic arm for automatically welding heat exchangers according to claim 6, characterized in that: One end of the connecting pipe (131) is connected to an external gas storage tank.

8. The robotic arm for automatically welding heat exchangers according to claim 7, characterized in that: multiple sets of... A support plate (150) is fixedly connected to the outer side of the regulating valve (140), and the baffle (151) is fixedly connected to one side of the support plate (150).

9. The robotic arm for automatically welding heat exchangers according to claim 8, characterized in that: The tilt angle of the inclined plate (152) is 30 degrees to 60 degrees.

10. The robotic arm for automatically welding heat exchangers according to claim 9, characterized in that: The bottom of the robotic arm body (100) is provided with a base (110).

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