Magnetic attraction type spherical tank welding seam detection robot

Abstract

The utility model relates to the technical field of spherical tank surface weld joint detection, in particular to a magnetic attraction type spherical tank weld joint detection robot which comprises a crawler crawling device, a weld joint detection device and a surface polishing device, and the crawler crawling device is used for providing walking power and adsorbing a climbing wall; the welding seam detection device is composed of a detection part and an imaging part, and the imaging part is composed of laser imaging equipment and infrared imaging equipment and used for scanning the interior and exterior of the spherical tank in the detection process and determining coordinate distribution of a welding seam; the detection part consists of a mechanical arm and flaw detection equipment and is used for detecting a welding seam; the surface grinding device is composed of a grinding wheel grinding machine and a sliding support. According to the spherical tank robot, the obstacle crossing capacity for the surface of the spherical tank is improved through the magnet, foreign matter on the welding seam and the surface of the spherical tank is removed through the grinding wheel polisher on the premise that the surface of the spherical tank is not damaged, the welding seam detection precision is improved, and nondestructive detection on the welding seam on the surface of the spherical tank is achieved through the welding seam detection device.

Description

Technical Field

[0001] The utility model relates to the technical field of weld detection on the surface of a spherical tank, in particular to a magnetic suction type spherical tank weld detection robot. Background Art

[0002] With the development of the energy industry and the adjustment of the energy structure, large spherical tanks are increasingly used in the fields of petroleum, chemical industry, metallurgy, etc. As a large-capacity, pressure-bearing spherical storage container, the spherical tank is mainly used to store flammable and explosive liquid and gas raw materials, such as liquefied petroleum gas, liquefied natural gas, etc. The spherical pressure vessel is assembled from multiple spherical petals. Since the spherical tank is under pressure for a long time and exposed to a complex environment, cracks and other defects are prone to occur at its welds, which seriously threatens the safe operation of the spherical tank and the safety of the surrounding environment.

[0003] Traditional spherical tank weld inspection mainly relies on manual work. Before inspection, the equipment needs to be stopped and scaffolding needs to be built around the spherical tank so that workers can reach a high place for point-by-point inspection. This method has many defects: first, the work is difficult and requires high physical fitness and safety skills of the inspectors; second, the inspection efficiency is low. Since manual point-by-point inspection is required, it takes a long time and is easily affected by human factors, which leads to doubts about the accuracy and reliability of the inspection results; in addition, manual inspection also has safety risks. Accidents are prone to occur during high-altitude operations, posing a threat to the life safety of inspectors.

[0004] In order to improve the efficiency and accuracy of spherical tank weld detection and reduce the safety risks of inspectors, some automated and intelligent weld detection technologies have been studied and applied in recent years. However, most of the existing automated weld detection technologies are suitable for the detection of flat or simple curved surface welds. There are still great technical difficulties and challenges for the detection of complex curved surface welds such as large spherical tanks. Therefore, the development of a robot that can move on the wall of a spherical tank and accurately detect the welds on the surface of the spherical tank has become an urgent need in the current field of weld detection. This robot needs to have flexible movement capabilities and be able to move freely on the surface of the spherical tank; at the same time, it also needs to have high-precision detection capabilities and be able to accurately identify weld defects to provide strong guarantees for the safe operation of the spherical tank.

[0005] In summary, the traditional spherical tank weld inspection technology has defects such as high difficulty, low inspection efficiency, and high safety risks, while the existing automated weld inspection technology is difficult to adapt to the inspection needs of complex curved welds on large spherical tanks. Therefore, the development of a new type of spherical tank weld inspection robot has important practical significance and application value. Summary of the invention

[0006] The purpose of the utility model is to provide a magnetic spherical tank weld inspection robot, which can replace manual inspection of spherical tanks with flammable and explosive media and high risk, improve the safety of spherical tank use, and reduce the risk of personnel inspection. It can solve the problems of insufficient adsorption and stability, inflexible movement and steering, inaccurate weld inspection, and imperfect autonomous navigation and intelligence of traditional robots.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is as follows.

[0008] A magnetic suction type spherical tank weld inspection robot, comprising:

[0009] A crawler crawling device, the crawler crawling device comprises a frame and at least four magnetic adsorption type crawler wheels, the four magnetic adsorption type crawler wheels are respectively arranged on both sides of the frame, and are used to provide walking power and adsorb climbing walls;

[0010] A weld detection device, which is arranged at the front of the vehicle frame. The weld detection device consists of a detection part and an imaging part. The imaging part consists of a laser imaging device and an infrared imaging device, which is used to scan the inside and outside of the spherical tank during the detection process to determine the coordinate distribution of the weld, thereby realizing the recognition and locking of the weld on the wall of the spherical tank; the detection part consists of a mechanical arm and a flaw detection device, and the flaw detection device is arranged at the top of the mechanical arm to detect the weld;

[0011] The surface grinding device is arranged at a lower position of the front end of the frame, and the surface grinding device is composed of a grinding wheel grinder and a sliding bracket. The grinding wheel grinder includes a grinding wheel drive motor, a grinding wheel, and a fixed support. The sliding bracket includes a base, a threaded slide rod, a slide groove, a sliding block, a sliding drive motor, and the base of the sliding bracket is fixedly connected to the front end of the frame. The slide groove is horizontally arranged and the top of the slide groove is fixedly connected to the base. The threaded slide rod is movably arranged inside the slide groove. The inner wall of the sliding block is provided with a thread. The sliding block is threadedly connected to the threaded slide rod. The output shaft of the sliding drive motor is fixedly connected to the threaded slide rod, and the sliding block can move horizontally along the slide groove and the threaded slide rod; the fixed support of the grinding wheel grinder is fixedly connected to the sliding block, the grinding wheel drive motor is embedded in the fixed support and fixedly connected to the fixed support, and the central axis of the grinding wheel is fixedly connected to the output shaft of the grinding wheel drive motor.

[0012] Furthermore, the magnetic adsorption type crawler wheel comprises two connecting rods, two lifting rods, two driving wheels, two induction wheels, two track rollers, two road wheels, and one track wheel. Each set of four gear combinations of the driving wheel with teeth, the induction wheel, the track roller, and the road wheel are arranged on the frame of the crawler chassis. Among them, the two connecting rods are arranged in parallel up and down, the two lifting rods are arranged in parallel left and right, and shaft holes are provided at both ends of the connecting rods and the lifting rods. The two connecting rods and the two lifting rods form a parallelogram. One end of the central axis of the two road wheels is respectively connected to the frame limit sleeve. The two road wheels The other end of the central axis passes through the axial holes at both ends of the lower connecting rod and the axial holes at the lower parts of the left and right lifting rods, and then is fixedly connected with the central axes of the two driving wheels. The central axes of the two track rollers are respectively sleeved in the axial holes at both ends of the upper connecting rod and the axial holes at the upper parts of the left and right lifting rods. At the same time, the road wheel and the track roller are meshed with each other, and the track roller and the inducer are meshed with each other. The track wheel is composed of multiple permanent magnet track monoliths, and the track wheel surrounds the two driving wheels and meshes with the two driving wheels. The central axis of each inducer is connected to a track chassis engine to provide walking driving force.

[0013] Furthermore, a spring shock absorber is provided on the magnetic adsorption type track wheel, and circular protrusions are provided on the two connecting rods. The upper end of the spring shock absorber is fixedly connected to the circular protrusion on the upper connecting rod, and the lower end of the spring shock absorber is fixedly connected to the circular protrusion on the lower connecting rod.

[0014] Furthermore, the laser imaging device is a laser probe, which is fixed to the vehicle frame via a connecting rod; and the infrared imaging device is an infrared sensor camera, which is fixed to the vehicle frame via a cantilever.

[0015] Furthermore, the cantilever is composed of a supporting bracket, a vertical connecting arm and a transverse connecting arm. The lower end of the supporting bracket is fixedly connected to the frame, and a longitudinal rotating motor is embedded in the upper end of the supporting bracket. The output shaft of the longitudinal rotating motor is fixedly connected to the lower end of the vertical connecting arm. The vertical connecting arm can rotate around the upper end point of the supporting bracket as the longitudinal rotating motor runs. A transverse rotating motor is embedded in the upper end of the vertical connecting arm. The output shaft of the transverse rotating motor is fixedly connected to the transverse connecting arm. The transverse connecting arm can rotate around the upper end point of the vertical connecting arm as the transverse rotating motor runs. An infrared sensor camera is fixed to the end of the other end of the transverse connecting arm.

[0016] Furthermore, the mechanical arm includes a rotating base, a lower support arm, a middle connecting arm, a hydraulic device, and an upper connecting shaft. The rotating base is fixed to the frame by bolts. The rotating base has its own driving motor. The rotating disk provided on the rotating base can be driven by the driving motor to rotate around its own center point. The lower end of the lower support arm is fixedly connected to the rotating disk on the rotating base, and a rotating driving motor is embedded in the upper end of the lower support arm. The output shaft of the rotating driving motor is fixedly connected to the lower end of the middle connecting arm. The middle connecting arm can rotate around the upper end point of the lower support arm with the operation of the rotating driving motor. The upper end of the middle connecting arm is rotatably connected to a fulcrum set at one end of the upper connecting shaft. The cylinder of the hydraulic device is arranged in parallel with the middle connecting arm, and the lower end of the cylinder of the hydraulic device is fixedly connected to the lower end of the middle connecting arm. The piston push rod of the hydraulic device is rotatably connected to the end of the upper connecting shaft. When the hydraulic device is in operation, the piston push rod extends or contracts to push the upper connecting shaft to rotate around the fulcrum; the flaw detection equipment is fixed to the end of the upper connecting shaft by threaded connection or bolt connection to achieve non-destructive detection of the weld.

[0017] Furthermore, at least three weight-reducing holes are provided on the upper connecting shaft of the robotic arm, and the weight-reducing holes are circular holes, square holes, triangular holes or special-shaped holes, and the multiple weight-reducing holes are staggered and distributed on the upper connecting shaft at intervals.

[0018] Furthermore, the flaw detection equipment is a non-destructive testing equipment, which may be an ultrasonic flaw detector.

[0019] Furthermore, the magnetic spherical tank weld inspection robot is also provided with a signal receiving device, which is arranged at the rear of the frame and includes a signal transceiver and a control circuit board. The control circuit board is electrically connected to the signal transceiver, the crawler device, the weld inspection device, and the surface grinding device at the same time. The signal transceiver and the control circuit board work together to transmit inspection information and control signals.

[0020] Furthermore, a tray is provided on the frame, which is located between the four magnetically adsorbed crawler wheels. The tray is connected to the frame by bolts and is used to carry machine parts, maintenance tools and other items.

[0021] Compared with the prior art, the advantages of the utility model are:

[0022] (1) The utility model designs a magnetic adsorption type track wheel for the spherical tank weld inspection robot. The wheel can be effectively adsorbed on the surface of the spherical tank. The permanent magnet installed above the track can provide stable and sufficient adsorption force, so that the spherical tank robot can move smoothly on the wall. In addition, the magnet above the track is easy to disassemble. For different loads, the size of its magnetic force can be changed by changing the number of magnets. The spherical tank robot can efficiently use the magnet and improve its ability to cope with different spherical tank surfaces and obstacle crossing.

[0023] (2) A grinding wheel grinder is installed at the front end of the robot to grind and remove the oxide film on the weld surface before the weld inspection. The grinding wheel grinder obtains the position information of the weld on the surface of the spherical tank through infrared imaging equipment and laser imaging equipment, and removes foreign matter between the weld and the surface of the spherical tank without damaging the surface of the spherical tank, providing a guarantee for improving the accuracy of weld inspection and laying a foundation for subsequent inspection work.

[0024] (3) A spring shock absorber is installed on the crawler device of the robot. When the weld inspection robot passes through a protruding weld during its movement on the spherical tank, the shock absorbing spring on the spring shock absorber is compressed by itself, causing the crawler wheel to lift upward, thereby reducing the impact load on the robot when passing through the weld and extending the service life of the crawler device.

[0025] (4) The multi-degree-of-freedom design of the robotic arm, laser probe, and infrared sensor camera enables the robot to detect welds more comprehensively and accurately, and send real-time status recordings to the staff. The multi-degree-of-freedom design of the robotic arm enables the robot to operate flexibly at different angles and positions, thereby covering a wider weld area. The multi-degree-of-freedom of the laser radar and infrared sensor camera provides better data collection and image capture capabilities, recording and transmitting weld inspection results to the staff in real time, and realizing non-destructive inspection of welds on the surface of the spherical tank. These innovative designs enable the robot to efficiently complete weld inspection tasks and provide necessary data support for subsequent analysis and decision-making.

[0026] (5) A remote control system is used to organically combine mechanical and electronic automation control through a signal receiving device, thereby achieving remote control. This means that the operator can remotely control the movement and operation of the robot without having to directly engage in complex or dangerous work, reducing the consumption of manpower and financial resources while ensuring the safety of the staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the three-dimensional structure of the magnetic suction type spherical tank weld inspection robot in the embodiment.

[0028] Figure 2 It is a schematic diagram of the top view of the structure of the magnetic suction type spherical tank weld inspection robot in the embodiment.

[0029] Figure 3 It is a schematic diagram of the front structure of the magnetic suction type spherical tank weld inspection robot in the embodiment.

[0030] Figure 4 It is a side structural schematic diagram of the magnetic suction type spherical tank weld inspection robot in the embodiment.

[0031] Figure 5 Schematic diagram of the structure of the magnetic adsorption type track wheel in the embodiment.

[0032] Figure 6 It is a schematic diagram of the side structure of the magnetic adsorption type track wheel in the embodiment.

[0033] Figure 7 Schematic diagram of the structure of the laser imaging device and the infrared imaging device in the embodiment.

[0034] Figure 8 Schematic diagram of the structure of the robotic arm in the embodiment.

[0035] Fig. 9 Schematic diagram of the structure of the surface grinding device in the embodiment.

[0036] Fig.10 FIG. 4 is a schematic diagram of the three-dimensional structure of the signal transceiver in the embodiment.

[0037] Fig.11 It is a schematic diagram of mechanical property analysis when a=45° in the embodiment.

[0038] Fig.12 It is a schematic diagram of mechanical property analysis when a=0° in the embodiment.

[0039] Fig.13 This is a schematic diagram of the structure of the upper coupling of the robotic arm that has not been lightweighted.

[0040] Fig.14 Schematic diagram of the structure of the lightweight upper connecting shaft of the robotic arm in the embodiment.

[0041] In the figure:

[0042] 1- crawler crawling device, 101- frame, 102- coupling rod, 103- driving wheel, 104- inducer wheel, 105- track roller, 106- road wheel, 107- track wheel, 108- permanent magnet track monolith, 109- spring shock absorber, 1010- crawler chassis engine, 1011- lifting rod;

[0043] 2-weld detection device, 201-laser imaging device, 202-laser probe, 203-infrared imaging device, 204-infrared sensor camera, 205-mechanical arm, 206-flaw detection equipment, 207-connecting rod, 208-cantilever, 209-support support, 2010-vertical connecting arm, 2011-lateral connecting arm, 2012-rotating base, 2013-lower supporting arm, 2014-middle connecting arm, 2015-hydraulic device, 2016-upper connecting shaft;

[0044] 3-surface grinding device, 301-grinding wheel grinder, 302-sliding bracket, 303-grinding wheel, 304-fixed support, 305-base, 306-slideway, 307-sliding block;

[0045] 4-signal receiving device, 401-signal transceiver, 402-control circuit board;

[0046] 5-Pallet. DETAILED DESCRIPTION

[0047] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. In the following description, many specific details are set forth to facilitate a full understanding of the utility model, but the utility model can also be implemented in other ways different from those described herein, and therefore, the utility model is not limited to the limitations of the specific embodiments disclosed below.

[0048] like Figures 1 to 10 As shown, the magnetic suction type spherical tank weld inspection robot of this embodiment is composed of four parts: a crawler crawling device 1, a weld inspection device 2, a surface grinding device 3, and a signal receiving device 4.

[0049] 1.1 Crawler device 1

[0050] The robot motion device uses magnetic adsorption type track wheels, such as Figure 1 , Figure 5 , Figure 6 As shown. Magnetic wheel transmission is a new transmission method realized by the magnetic principle. It has the advantages of simple structure, low noise and low wear, so it is widely used in more and more industries. Magnetic wheel transmission mainly uses the principle of magnetic attraction and magnetic repulsion, so that the object being driven is adsorbed on the surface of the spherical tank by the magnetic force generated by the magnet on the track, and will not fall off the surface of the spherical tank. The material of the spherical tank body is generally steel, which can be magnetized and adsorbed by magnetism.

[0051] Specifically, the crawler crawling device 1 includes a frame 101 and at least four magnetic adsorption type crawler wheels. In this embodiment, four magnetic adsorption type crawler wheels are provided, and each magnetic adsorption type crawler wheel includes two connecting rods 102, two lifting rods 1011, two driving wheels 103, two induction wheels 104, two track rollers 105, two road wheels 106, and a crawler wheel 107. The driving wheel 103, the induction wheel 104, the track roller 105, The road wheels 106 are all toothed transmission wheels. Each set of toothed driving wheels 103, idler wheels 104, support wheels 105, and road wheels 106 are arranged on the frame 101 of the crawler chassis. Among them, two connecting rods 102 are arranged in parallel up and down, and two lifting rods 1011 are arranged in parallel left and right. Both ends of the connecting rods 102 and the lifting rods 1011 are provided with shaft holes. The two connecting rods 102 and the two lifting rods 1011 form a parallel The vehicle body 101 is in the shape of a quadrilateral, one end of the central axis of the two road wheels 106 is respectively limitedly sleeved with the frame 101 (the sleeve connection method will not limit the rotation of the central axis), the other end of the central axis of the two road wheels 106 passes through the axial holes at both ends of the lower connecting rod 102 and the axial holes at the lower parts of the left and right lifting rods 1011, and then is fixedly connected with the central axes of the two driving wheels 103 respectively, the central axes of the two track rollers 105 are respectively sleeved in the axial holes at both ends of the upper connecting rod 102 and the axial holes at the upper parts of the left and right lifting rods 1011, at the same time, the road wheels 106 and the track rollers 105 are meshed with each other, and the track rollers 105 and the inducer wheels 104 are meshed with each other; the track wheels 107 are composed of a plurality of permanent magnet track monoliths 108, the track wheels 107 surround the two driving wheels 103 and mesh with the two driving wheels 103, and the central axis of each inducer wheel 104 is connected to a track chassis engine 1010 to provide walking driving force.

[0052] A plurality of magnets that can be fixed and installed by screws and can be quickly disassembled and assembled are installed on each track wheel 107. The magnet has strong adsorption force, does not require additional energy consumption, and can flexibly select different magnetic forces and different numbers of magnets according to the size of the load to adapt to different adsorption force requirements. In this embodiment, a permanent magnet is used as a magnet, which has strong magnetic force and stable magnetic properties. At the same time, a spring shock absorber 109 is installed next to each magnetic adsorption type track wheel, and two connecting rods 102 are provided with circular protrusions. The upper end of the spring shock absorber 109 is fixedly connected with the circular protrusion on the upper connecting rod 102, and the lower end of the spring shock absorber 109 is fixedly connected with the circular protrusion on the lower connecting rod 102. When the robot passes through the raised weld on the surface of the spherical tank, the spring shock absorber 109 can effectively absorb the impact load, and play a buffering and shock-absorbing role on the support wheel 105, the load-bearing wheel 106 and the track wheel 107, thereby reducing the damage to the spherical tank weld detection robot and increasing its service life.

[0053] 1.2 Weld detection device 2

[0054] like Figure 2 , Figure 3 , Figure 7 As shown, the weld detection device 2 is composed of a detection part and an imaging part. The imaging part is composed of a laser imaging device 201 and an infrared imaging device 203, which are used to scan the inside and outside of the spherical tank during the detection process to determine the coordinate distribution of the weld, thereby realizing the recognition and locking of the weld on the wall of the spherical tank. The laser imaging device 201 is a laser probe 202, which is fixed to the frame 101 through a connecting rod 207 with a manually adjustable angle; the infrared imaging device 203 is an infrared sensor camera 204, which is fixed to the frame 101 through a cantilever 208 with an adjustable angle. The cantilever 208 is composed of a support bracket 209, a vertical connecting arm 2010 and a horizontal connecting arm 2011. The lower end of the support bracket 209 is fixedly connected to the frame 101, and the upper end of the support bracket 209 is embedded with a longitudinal rotating motor. The output shaft of the machine is fixedly connected to the lower end of the vertical connecting arm 2010, and the vertical connecting arm 2010 can rotate around the upper end point of the support bracket 209 as the longitudinal rotating motor runs. A transverse rotating motor is embedded in the upper end of the vertical connecting arm 2010, and the output shaft of the transverse rotating motor is fixedly connected to the transverse connecting arm 2011, and the transverse connecting arm 2011 can rotate around the upper end point of the vertical connecting arm 2010 as the transverse rotating motor runs. The infrared sensor camera 204 is fixed to the end of the other end of the transverse connecting arm 2011.

[0055] The detection part is composed of a mechanical arm 205 and a flaw detection device 206. The mechanical arm 205 includes a rotating base 2012, a lower support arm 2013, a middle connecting arm 2014, a hydraulic device 2015, and an upper connecting shaft 2016. The rotating base 2012 is fixed to the frame 101 by bolts. The rotating base 2012 has its own driving motor. The rotating disk provided on the rotating base 2012 can be driven by the driving motor to rotate around its own center point. The lower end of the lower support arm 2013 is fixedly connected to the rotating disk on the rotating base 2012. A rotating driving motor is embedded in the upper end of the lower support arm 2013. The output shaft of the rotating driving motor is fixedly connected to the lower end of the middle connecting arm 2014. The middle connecting arm 201 4 can rotate around the upper end of the lower support arm 2013 with the operation of the rotary drive motor, the upper end of the middle connecting arm 2014 is rotatably connected to the fulcrum set at one end of the upper connecting shaft 2016, the cylinder of the hydraulic device 2015 is arranged in parallel with the middle connecting arm 2014, and the lower end of the cylinder of the hydraulic device 2015 is fixedly connected to the lower end of the middle connecting arm 2014, the piston push rod of the hydraulic device 2015 is rotatably connected to the end of the upper connecting shaft 2016, when the hydraulic device 2015 is running, the piston push rod extends or contracts, pushing the upper connecting shaft 2016 to rotate around the fulcrum; the flaw detection device 206 can be fixed to the end of the upper connecting shaft 2016 by threaded connection or bolt connection, and can realize non-destructive detection of the weld. The flaw detection device 206 adopts non-destructive detection equipment, which can be an ultrasonic flaw detector, such as GE ultrasonic flaw detector Phasor XS. The non-destructive detection equipment does not directly contact the object to be detected during detection, so it will not cause damage to the wall surface during the detection process. In addition, nondestructive testing equipment also has the advantages of high detection accuracy and fast processing speed.

[0056] The multifunctional robotic arm 205 can be equipped with other tools to assist the robot when needed, such as a water spray pipe, etc. One end of the water spray pipe is fixed to the end of the upper connecting shaft 2016 of the robotic arm 205 by means of a clamp or rope. The robot brings the water pipe head to the designated position, and water can be pumped through the ground water pump to perform spraying and cleaning work. At the same time, the movement of the robotic arm 205 is driven by the hydraulic device 2015. The hydraulic device 2015 adopts the existing conventional hydraulic piston rod. The hydraulic device 2015 can control the flow direction and flow rate of the fluid through the internally arranged solenoid valve to achieve more accurate power output, making the machine movement smoother and the power output more stable. The components of the hydraulic device 2015, such as the hydraulic pump, liquid container, valve, etc., have a long service life, are easy to filter and repair, and are convenient to maintain. In addition, the hydraulic device 2015 itself has a certain shockproof and vibration reduction effect, which can reduce the vibration and noise of the machine during operation and reduce the loss of equipment. The structure of the robotic arm 205 is as follows Figure 8 shown.

[0057] like Figure 2, Figure 3 As shown, the weld detection device 2 is arranged at the front of the frame 101 of the crawler chassis, between the two front magnetic adsorption type crawler wheels, and the mechanical arm 205 carrying the flaw detection equipment 206, the laser imaging equipment 201 and the infrared imaging equipment 203 are arranged in sequence from left to right.

[0058] 1.3 Surface grinding device 3

[0059] like Figure 2 , Figure 4 As shown, the surface grinding device 3 is arranged at the lower front end of the frame 101 of the crawler chassis and is located in front of the laser imaging device 201. Fig. 9 As shown, the surface grinding device 3 is composed of a grinding wheel grinder 301 and a sliding bracket 302. The grinding wheel grinder 301 includes a grinding wheel drive motor, a grinding wheel 303, and a fixed support 304. The sliding bracket 302 includes a base 305, a threaded slide rod, a slide groove 306, a sliding block 307, and a sliding drive motor. The base 305 of the sliding bracket 302 is fixedly connected to the front end of the frame 101, the slide groove 306 is horizontally arranged and the top of the slide groove 306 is fixedly connected to the base 305, the threaded slide rod is movably arranged inside the slide groove 306, the inner wall of the sliding block 307 is provided with threads, and the sliding block 307 is provided with threads. 07 is threadedly connected to the threaded slide rod, and the output shaft of the sliding drive motor is fixedly connected to the threaded slide rod. When the sliding drive motor is running, it drives the threaded slide rod to rotate so that the sliding block 307 embedded in the slide groove 306 can move horizontally along the slide groove 306 and the threaded slide rod; the fixed support 304 of the grinding wheel grinder 301 is fixedly connected to the sliding block 307, the grinding wheel drive motor is located on the side of the grinding wheel 303, and the grinding wheel drive motor is embedded in the fixed support 304 and fixedly connected to the fixed support 304, and the central axis of the grinding wheel 303 is fixedly connected to the output shaft of the grinding wheel drive motor.

[0060] The spherical tank body is exposed to the external environment for a long time, and its surface will be covered with a layer of oxide film and other impurities. If these impurities are not polished and removed regularly, these impurities will cause corrosion to the welds on the tank wall. In addition, the impurities covering the surface will also interfere with the weld inspection. Therefore, the oxide film on the weld surface must be polished and removed before the weld inspection. The grinding wheel grinder 301 obtains the position information of the weld on the surface of the spherical tank through the infrared imaging device 203 and the laser imaging device 201, and removes foreign matter between the weld and the surface of the spherical tank without damaging the surface of the spherical tank, thereby providing a guarantee for improving the accuracy of weld detection.

[0061] 1.4 Signal receiving device 4

[0062] like Figure 1 , Fig.10As shown, the signal receiving device 4 is arranged at the rear of the vehicle frame 101, and includes a signal transceiver 401 and a control circuit board 402. The signal receiving device 4 is installed at the rear end of the robot, which can remotely control the robot's actions and transmit data at the same time. The signal receiving device 4 is used to receive the scanning results of the imaging device and transmit them to the remote central processing system (CPU) and generate the weld coordinate distribution. At the same time, the detection results of the flaw detection device 206 are transmitted to the background detection mechanism of the remote central processing system for identification and analysis, and the walking drive command signal, detection command signal, and cleaning and grinding command signal issued by the remote central processing system are respectively transmitted to the crawler crawling device 1, the weld detection device 2, and the surface grinding device 3 to realize the remote control of the robot; the control circuit board 402 is electrically connected to the signal transceiver 401 and various devices of the robot such as the crawler crawling device 1, the weld detection device 2, and the surface grinding device 3. The signal transceiver 401 and the control circuit board 402 cooperate with each other to transmit detection information and control signals. Specifically, the walking drive command signal is transmitted to the crawler chassis engine 1010 to control the robot's moving position; the angle adjustment signal is transmitted to the longitudinal rotation motor and the lateral rotation motor inside the cantilever 208 and the rotating base 2012, the rotating drive motor, and the hydraulic device 2015 inside the mechanical arm 205 to control and adjust the detection angle of the infrared sensor camera 204 and the flaw detection device 206; the data obtained by the laser probe 202, the infrared sensor camera 204, and the flaw detection device 206 are transmitted to the control end computer (i.e., the remote central processing system CPU) for data analysis; the weld position signal is transmitted to the sliding bracket 302 to control the moving position of the grinding wheel grinder 301; the grinding depth is transmitted to the grinding wheel grinder 301 to control the grinding wheel 303 to rotate at a high speed for grinding. The robot frame 101 is equipped with a mobile power supply for powering various electrical devices.

[0063] 1.5 Pallet 5

[0064] The tray 5 can be used to carry some articles, and the tray 5 is connected to the frame 101 by bolts. The tray 5 can be made of magnetic material or installed with a cover, and some machine parts or maintenance tools can be placed in the tray 5 for the convenience of the staff to take and replace.

[0065] 2. Static mechanical analysis

[0066] 2.1 Force analysis of robot climbing wall

[0067] When the magnetic spherical tank weld inspection robot works on the surface of a large spherical tank container, in order to ensure the stability of its movement, it has high requirements for its adsorption, that is, the robot must be firmly adsorbed on the wall without falling off, and at the same time, its movement flexibility must be guaranteed. In order to analyze the stability of the wall-climbing robot on the container wall, this embodiment establishes the following Fig.11 , Fig.12 The static mechanical analysis model shown is used to analyze the force of the robot when it is at 45° and 0° to the ground:

[0068] In order to make the robot firmly adsorbed on the surface of the spherical tank, the following mechanical equations need to be satisfied:

[0069] 4F f -mg·cos a≥0 (1)

[0070] F f =μF n (2)

[0071] 4F n + mg·sin a=M·F m (3)

[0072] Among them, F f F is the friction between a single track (single track wheel 107) and the wall; m is the adsorption force of a single permanent magnet on the wall; F n is the supporting force of the wall on a single track; mg is the deadweight of the wall-climbing robot; μ is the static friction coefficient between the container wall and the track; M is the number of permanent magnets in contact with the wall; a is the angle between the robot and the ground, cos a is the cosine of angle a, and sin a is the sine of angle a.

[0073] 1) Combining the above formulas (1), (2) and (3), we can get:

[0074]

[0075] 2) When a=0, the wall-climbing robot is on a vertical wall. At this time, the wall-climbing robot should satisfy the following conditions in order not to slide down:

[0076]

[0077] 3) When a = 45°, the wall-climbing robot is hanging upside down on the wall. At this time, there must be sufficient adsorption force, which should meet the following requirements:

[0078]

[0079] According to our design, in this embodiment, the mass of the magnetic spherical tank weld inspection robot (i.e., the weight of the wall-climbing robot mg) is 8.24 kg, the gravity is 82.400 N, the static friction coefficient μ between the container wall and the track is 0.2, and the number of permanent magnets in contact with the wall is selected as 20 in the experiment. The adsorption force of a single permanent magnet is 7.04 N, and the adsorption force of the total permanent magnet is 140.8 N. Therefore, the wall-climbing robot can meet the stable adsorption requirements on ordinary walls or hanging walls.

[0080] 2.2 Force analysis of the robotic arm

[0081] In addition, we have optimized the topological structure of the robot arm 205, such as Fig.13 , Fig.14 As shown, in this embodiment, a plurality of weight-reducing holes of different shapes and sizes are added to the upper connecting shaft 2016 of the robot arm 205. The weight-reducing holes can be circular holes, square holes, triangular holes or holes of irregular shapes. Each upper connecting shaft 2016 is provided with at least three weight-reducing holes according to the size. Fig.14 As shown, in this embodiment, triangular weight-reducing holes are used, and five weight-reducing holes are arranged on the upper connecting shaft 2016, and the five weight-reducing holes are staggered and distributed on the upper connecting shaft 2016. After the lightweight optimization design, the weight of the robot arm 205 is reduced while ensuring the rigidity. Through the lightweight design process, the robot arm 205 can move more flexibly and efficiently during operation, and can reduce the pressure on other connecting parts, thereby extending the life and reliability of the robot.

[0082] In addition, we conducted a detailed force analysis and comprehensively considered the force conditions of the robot arm 205 under various operating conditions. By simulating under different workloads, we verified that the robot arm 205 can withstand the required stress and maintain its normal operation.

[0083] The mechanical arm 205 has the requirements of high precision, high speed, high load and other performances. For this reason, we have carried out a lightweight design on the upper connecting shaft 2016 of the mechanical arm 205. We have selected 6061 high-hardness aluminum alloy to replace steel as the material of the upper connecting shaft 2016 of the mechanical arm 205. The 6061 aluminum alloy has high strength, high elongation and good corrosion resistance. Without reducing the bearing capacity of the parts, the weight of the parts is reduced by carrying out a lightweight design on the upper connecting shaft 2016, and the performance and quality of the product are improved. Stress analysis found that the structural strength of the connecting shaft did not decrease after lightweighting, while the structural weight was reduced by 50%. In addition, if carbon fiber material is used, the weight of the connecting shaft can be made smaller, but carbon fiber material is expensive. After comprehensive consideration, we decided to use 6061 aluminum alloy as the material used for the lightweight design of the upper connecting shaft 2016 in this embodiment.

[0084] The magnetic spherical tank weld processing robot of the utility model is an automated device designed for large spherical tank weld detection, and its working principle is based on the coordinated work of the mechanical movement of the crawler device 1, the magnetic adsorption technology and the intelligent detection system (weld detection device 2, signal receiving device 4).

[0085] Mechanical movement: The robot moves on the wall of the spherical tank through its internal high-precision crawler crawling device 1. The crawler crawling device 1 is composed of a crawler chassis engine 1010, a spring shock absorber 109, a gear transmission mechanism such as a driving wheel 103, and a crawler wheel 107, which can drive the robot to move in all directions on the surface of the spherical tank. The robot adopts a crawler design to adapt to the curved surface structure of the spherical tank and can be flexibly adjusted at different weld positions.

[0086] Magnetic adsorption technology: Magnetic adsorption technology is used to ensure the stable attachment of the robot to the wall of the spherical tank. Strong magnets are installed on the track wheels 107 at the bottom of the robot. These magnets can generate sufficient adsorption force when the robot is working, so that the robot fits tightly to the wall of the spherical tank to prevent it from falling off due to gravity or external force during the detection process.

[0087] Intelligent detection system: The front detection device of the robot is its core part, including a laser probe 202 and an infrared sensor camera 204. During the detection process, the laser probe 202 and the infrared sensor camera 204 scan the inside and outside of the spherical tank to determine the coordinate distribution of the weld, thereby realizing the recognition and locking of the weld on the wall of the spherical tank. During the detection process, the robot obtains the image and data of the weld through the front detection device, and analyzes and judges it through the remote central processing system CPU. The remote central processing system CPU adopts the existing system and is loaded with existing analysis tools. It can automatically identify the defect type, location and size of the weld according to preset parameters and algorithms, and display the results in real time on the operation interface. The remote central processing system CPU, analysis tools and analysis methods belong to existing well-known technologies and are not within the scope of protection of this application, so they will not be elaborated here.

[0088] Other devices: In addition to the above core devices, the robot is also equipped with other auxiliary devices, such as surface grinding device 3. The surface grinding device 3 is used to clean the dust and dirt on the weld surface before detection to improve the detection accuracy and to perform preliminary cleaning work after the weld defects are found, so as to prepare for the subsequent repair work.

[0089] In actual application, the staff first controls the robot to the top of the spherical tank through the signal receiving device 4, and scans the terrain through the imaging part in front of the robot to obtain a three-dimensional overall picture. Then, the staff controls the robot to reach the designated location for flaw detection through the signal receiving device 4. During the flaw detection process, the imaging part first determines the weld position, then the surface grinding device 3 cleans the weld surface, and then the flaw detection device 206 carried by the robot arm 205 performs flaw detection, and finally the signal receiving device 4 performs data transmission and remote control.

Claims

1. A magnetic spherical tank weld inspection robot, characterized in that: include: A crawler crawling device, the crawler crawling device comprises a frame and at least four magnetic adsorption type crawler wheels, the four magnetic adsorption type crawler wheels are respectively arranged on both sides of the frame, and are used to provide walking power and adsorb climbing walls; A weld detection device, which is arranged at the front of the vehicle frame. The weld detection device consists of a detection part and an imaging part. The imaging part consists of a laser imaging device and an infrared imaging device. The detection part consists of a mechanical arm and a flaw detection device. The flaw detection device is arranged at the top of the mechanical arm. The laser imaging device, the infrared imaging device and the flaw detection device are used to scan the inside and outside of the spherical tank during the detection process to determine the coordinate distribution of the weld; The surface grinding device is arranged at a lower position of the front end of the frame, and the surface grinding device is composed of a grinding wheel grinder and a sliding bracket. The grinding wheel grinder includes a grinding wheel drive motor, a grinding wheel, and a fixed support. The sliding bracket includes a base, a threaded slide rod, a slide groove, a sliding block, and a sliding drive motor. The base of the sliding bracket is fixedly connected to the front end of the frame, the slide groove is horizontally arranged and the top of the slide groove is fixedly connected to the base, the threaded slide rod is movably arranged inside the slide groove, the inner wall of the sliding block is provided with threads, the sliding block is threadedly connected to the threaded slide rod, the output shaft of the sliding drive motor is fixedly connected to the threaded slide rod, and the sliding block can move horizontally along the slide groove and the threaded slide rod; the fixed support of the grinding wheel grinder is fixedly connected to the sliding block, the grinding wheel drive motor is embedded in the fixed support, and the central axis of the grinding wheel is fixedly connected to the output shaft of the grinding wheel drive motor.

2. The magnetic spherical tank weld inspection robot according to claim 1 is characterized in that: The magnetic adsorption type crawler wheel comprises two connecting rods, two lifting rods, two driving wheels, two induction wheels, two track rollers, two road wheels and a track wheel. Each set of toothed driving wheels, induction wheels, track rollers and road wheels is arranged on the frame of the crawler chassis. The two connecting rods are arranged in parallel up and down, the two lifting rods are arranged in parallel left and right, and shaft holes are provided at both ends of the connecting rods and the lifting rods. The two connecting rods and the two lifting rods form a parallelogram. One end of the central axis of the two road wheels is respectively connected to the frame limit sleeve. The center axis of the two road wheels is connected to the frame limit sleeve. The other end of the shaft passes through the shaft holes at both ends of the lower connecting rod and the shaft holes at the lower parts of the left and right lifting rods, and is fixedly connected with the central shafts of the two driving wheels respectively. The central shafts of the two track rollers are respectively sleeved in the shaft holes at both ends of the upper connecting rod and the shaft holes at the upper parts of the left and right lifting rods. At the same time, the road wheel and the track roller are meshed with each other, and the track roller and the inducer are meshed with each other. The track wheel is composed of multiple permanent magnet track monoliths, and the track wheel surrounds the two driving wheels and is meshed with the two driving wheels. The central shaft of each inducer is connected to a track chassis engine to provide walking driving force.

3. The magnetic spherical tank weld inspection robot according to claim 2 is characterized in that: A spring shock absorber is also provided. Two connecting rods are provided with round bumps. The upper end of the spring shock absorber is fixedly connected to the round bump on the upper connecting rod, and the lower end of the spring shock absorber is fixedly connected to the round bump on the lower connecting rod.

4. The magnetic spherical tank weld inspection robot according to claim 1 is characterized in that: The laser imaging device is a laser probe, which is fixed to the frame through a connecting rod; the infrared imaging device is an infrared sensor camera, which is fixed to the frame through a cantilever; the cantilever is composed of a support bracket, a vertical connecting arm and a transverse connecting arm, the lower end of the support bracket is fixedly connected to the frame, the upper end of the support bracket is embedded with a longitudinal rotating motor, the output shaft of the longitudinal rotating motor is fixedly connected to the lower end of the vertical connecting arm, and the vertical connecting arm can rotate around the upper end point of the support bracket with the operation of the longitudinal rotating motor, the upper end of the vertical connecting arm is embedded with a transverse rotating motor, the output shaft of the transverse rotating motor is fixedly connected to the transverse connecting arm, and the transverse connecting arm can rotate around the upper end point of the vertical connecting arm with the operation of the transverse rotating motor, and the infrared sensor camera is fixed to the end of the other end of the transverse connecting arm.

5. The magnetic spherical tank weld inspection robot according to claim 1 is characterized in that: The mechanical arm comprises a rotating base, a lower support arm, a middle connecting arm, a hydraulic device, and an upper connecting shaft. The rotating base is fixed to the frame by bolts. The rotating base has its own driving motor. The rotating base is provided with a rotating disk which can be driven by the driving motor to rotate around its own center point. The lower end of the lower support arm is fixedly connected to the rotating disk on the rotating base. A rotating driving motor is embedded at the upper end of the lower support arm. The output shaft of the rotating driving motor is fixedly connected to the lower end of the middle connecting arm. The middle connecting arm can rotate around the upper end point of the lower support arm with the operation of the rotating driving motor. The upper end of the middle connecting arm is rotatably connected to a fulcrum arranged at one end of the upper connecting shaft. The cylinder of the hydraulic device is arranged in parallel with the middle connecting arm, and the lower end of the cylinder of the hydraulic device is fixedly connected to the lower end of the middle connecting arm. The piston push rod of the hydraulic device is rotatably connected to the end of the upper connecting shaft. When the hydraulic device is running, the piston push rod extends or contracts to push the upper connecting shaft to rotate around the fulcrum. The flaw detection equipment is fixed to the end of the upper connecting shaft by threaded connection or bolt connection to realize non-destructive detection of the weld.

6. The magnetic spherical tank weld inspection robot according to claim 5 is characterized in that: The upper connecting shaft of the robotic arm is also provided with at least three weight-reducing holes, which are circular holes, square holes, triangular holes or special-shaped holes, and the plurality of weight-reducing holes are staggered and distributed at intervals on the upper connecting shaft.

7. The magnetic spherical tank weld inspection robot according to claim 5 is characterized in that: The flaw detection equipment is an ultrasonic flaw detector.

8. The magnetic spherical tank weld inspection robot according to claim 1 is characterized in that: A signal receiving device is also provided, which is arranged at the rear of the frame and includes a signal transceiver and a control circuit board. The control circuit board is electrically connected to the signal transceiver, the crawler device, the weld detection device, and the surface grinding device. The signal transceiver and the control circuit board work together to transmit detection information and control signals.

9. The magnetic spherical tank weld inspection robot according to claim 1 is characterized in that: There is also a pallet on the frame, which is located between the four magnetically adsorbed track wheels. The pallet is connected to the frame by bolts and is used to carry machine parts and maintenance tools.

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