Ultrasonic detection device for field detection of large pressure vessel

Abstract

The invention discloses an ultrasonic detection device for on-site detection of a large pressure vessel, which comprises an ultrasonic probe, an ultrasonic flexible track coating mechanism, a vacuum chuck fixing device, an along-track oil filling pushing device, a vertical track pushing device and a controller, and is characterized in that the ultrasonic probe is arranged in the ultrasonic flexible track coating mechanism; the two ends of the ultrasonic flexible track wrapping mechanism are tightly attached to the outer wall of the pressure container through vacuum suction cup fixing devices, the bottom face, making contact with the wall of the pressure container, of the ultrasonic flexible track wrapping mechanism is coated with oil and tightly attached to the wall of the pressure container without air, and the interior of a track of the ultrasonic flexible track wrapping mechanism is filled with oil. A micro oil pump in the along-track oil filling pushing device is used for achieving slow displacement motion of an ultrasonic probe in the direction of a flexible track, the outer side of an ultrasonic flexible track coating mechanism is tightly buckled with a flexible track coating belt clamping sleeve, and the side wall of the flexible track coating belt clamping sleeve is connected with a vertical track pushing device. The thrust motion perpendicular to the track is provided by controlling the motion of the stepping motor, and internal cracks possibly appearing at the welding seam of the pressure container are detected. The method can achieve the automatic fine detection of a local region, and is suitable for the multi-time repeated detection of the same region.

Description

Technical Field

[0001] The invention belongs to the technical field of container detection, and in particular relates to an ultrasonic detection device used for on-site detection of large pressure containers. Background Art

[0002] Pressure vessels are used to contain liquids or gases with a certain pressure and are an important part of chemical production equipment. Pressure vessel testing is an indispensable and important link to ensure the safety and reliability of pressure vessels during use. Large pressure vessels used in general chemical production are made of steel plate welding technology, so pressure vessel testing mainly tests the welds of pressure vessel welding parts. Pressure vessel testing is divided into factory inspection and regular annual inspection. Welding defects such as slag inclusions, pits, pores, undercuts, weld nodules, partial burn-through, and incomplete penetration are generally detected in factory inspection. Regular annual inspections mainly detect internal cracks in welds that may occur during use. Pressure vessel testing includes X-ray, ultrasonic, magnetic flaw detection and other methods. Since factory inspection has not been installed and used, one or more combinations of them can be used flexibly for testing. However, due to the large size of the equipment and the installation of multiple types of pipelines and lines, the regular inspection of pressure vessels during use cannot be disassembled and returned to the factory for inspection. It can only be inspected at the industrial site. At this time, the radiation effect of X-rays and the low accuracy of magnetic flaw detection are more obvious. The main detection method is ultrasonic testing. Compared with X-ray testing, ultrasonic testing does not involve radiation and is safer for testing personnel. However, ultrasonic testing is very sensitive to the position coupling between the ultrasonic probe and the pressure vessel wall. The positional relationship between the ultrasonic probe and the pressure vessel wall needs to be finely adjusted. Otherwise, missed detection and false detection are likely to occur.

[0003] Disadvantages of existing technology:

[0004] At present, ultrasonic testing of pressure vessels in industrial sites is mainly based on manual testing. The surface of the pressure vessel is polished, coupling agents such as engine oil are sprayed, and a handheld ultrasonic probe is used to repeatedly detect along the side of the weld to observe the ultrasonic echo data. This method is the most traditional and effective method, but due to the huge workload of manual testing and the harsh on-site environment, only sampling testing can be carried out. The areas that are not sampled still have safety risks such as cracks inside the weld. An alternative method that saves manpower is to install a scaffold as a support in the area where the pressure vessel is to be tested, fix the ultrasonic probe on a two-dimensional movable bracket, and adjust the contact tightness between the probe and the wall of the pressure vessel, and realize the automatic detection of ultrasonic testing by controlling the movement of a two-dimensional motor. This method requires a large amount of scaffolding installation work, and there are generally a large number of pipelines and line connections near the pressure vessel in the industrial site, and there is no space for scaffolding installation. Therefore, this method also greatly limits the ultrasonic detection range of the pressure vessel. Another more advanced alternative method is to install the ultrasonic probe on an adsorption-type wall-climbing trolley, and drive the ultrasonic probe for detection by the movement of the trolley along the direction of the weld. This method can greatly save manpower, but it also has the following disadvantages: (1) Ultrasonic detection is very sensitive to the position coupling between the probe and the pressure vessel wall. A slight change in the angle or position of the probe will introduce a large change in the ultrasonic echo, which will make it difficult for the control accuracy of the trolley to meet the requirements of ultrasonic probe detection, resulting in a large number of missed detections and false detections; (2) A large number of pipelines and line connections near the pressure vessel will limit the detection area of ​​the wall-climbing trolley and bring safety hazards to the movement of the wall-climbing trolley; (3) This type of wall-climbing trolley with complex control usually requires high professionalism from the operator and is complex to use and maintain. (4) Some chemical companies have restricted entry requirements for battery-powered wall-climbing trolleys, prohibiting entry or requiring them to meet explosion-proof safety levels. Summary of the invention

[0005] In view of the shortcomings of the prior art in ultrasonic detection of pressure vessels at industrial sites, the present invention provides an ultrasonic detection device for on-site detection of large pressure vessels. By utilizing the characteristics of small size and light weight of the ultrasonic detection probe, a lightweight structure is developed that can be conveniently installed on the pressure vessel body. The slow movement of the ultrasonic probe along the weld direction and the direction perpendicular to the weld can be precisely controlled. By adjusting the size of the mounting rod and the flexible track, the detectable area of ​​the pressure vessel weld can be increased as much as possible. Automated and precise detection of local areas can be achieved and the device is suitable for repeated detection in the same area. The equipment cost is low and there are no other safety hazards in use.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an ultrasonic detection device for on-site detection of large pressure vessels, comprising an ultrasonic probe, an ultrasonic flexible track covering mechanism, a vacuum suction cup fixing device, an oil filling and pushing device along the track, a vertical track pushing device and a controller, wherein the ultrasonic probe is placed in the ultrasonic flexible track covering mechanism, and both ends of the ultrasonic flexible track covering mechanism are tightly attached to the outer wall of the pressure vessel through the vacuum suction cup fixing device. The track of the ultrasonic flexible track covering mechanism is filled with oil, and a micro oil pump in the oil filling and pushing device along the track is used to realize the slow displacement movement of the ultrasonic probe along the direction of the flexible track. The side wall of the ultrasonic flexible track covering mechanism is connected to the vertical track pushing device, and the thrust movement of the vertical track is provided by controlling the movement of the stepping motor to realize the detection of internal cracks that may appear at the weld of the pressure vessel.

[0007] Preferably, the ultrasonic flexible track covering mechanism comprises a polymer flexible track and a film covering sleeve covering the outside of the polymer flexible track, hard sealing ends are provided at both ends of the film covering sleeve, the interior of the polymer flexible track is filled with oil, the structure of its inner wall is consistent with the outer contour of the ultrasonic detection probe, and the thickness of the film covering sleeve is less than half the wavelength of the ultrasonic wave used for detection.

[0008] Preferably, the polymer flexible track is connected to the track oil filling and pushing device through No. 01 wire penetration piece, No. 01 oil pipe penetration piece, No. 01 high-frequency wire penetration piece, and No. 02 oil pipe penetration piece under the covering of the film covering sleeve, and the cavity structure and connecting pipelines of the polymer flexible track are all sealed and filled with oil; wherein the detection data line of the ultrasonic detection probe passes through the ultrasonic detection high-frequency line, passes through the No. 01 high-frequency wire penetration piece, and under the protection of the high-frequency wire casing, passes through the No. 02 high-frequency wire penetration piece to connect with the automatic wire take-up device inside the track oil filling and pushing device, and the automatic wire take-up device is connected to the controller through the ultrasonic detector control line to realize the control of the ultrasonic detection probe's transmitting wave and the data collection of the receiving wave; the displacement data of the ultrasonic detection probe along the track is connected to the wire sensor inside the track oil filling and pushing device through the displacement sensor wire, passes through the No. 01 wire penetration piece, the wire casing, and the No. 02 wire penetration piece, and the wire sensor is connected to the controller through the wire sensor control line to realize the recording of the ultrasonic detection probe's position along the track direction and the data feedback of the position movement along this direction.

[0009] Preferably, the polymer flexible track is connected to the micro oil pump through No. 01 oil pipe penetration piece, No. 01 oil pipe, and No. 04 oil pipe penetration piece under the covering of the film cover. The micro oil pump then returns to communicate with the interior of the polymer flexible track through No. 03 oil pipe penetration piece, No. 02 oil pipe, and No. 02 oil pipe penetration piece to form an internally completely sealed oil filling circuit. The micro oil pump is also connected to the controller through a micro oil pump watertight connector and a micro oil pump control line. The controller controls the rotation speed of the micro oil pump, so that the oil pressure difference at both ends of the ultrasonic detection probe changes. The ultrasonic detection probe can move slowly along the direction of the flexible track under the push of the oil pressure difference.

[0010] Preferably, the oil-filled pushing device along the track is an oil-filled sealed box, which is used to place a micro oil pump, an automatic wire take-up device, a wire pulling sensor, and connect the oil-filled oil circuit, the line end and the non-oil-filled line end of the controller of the ultrasonic flexible track covering mechanism. In order to reduce the disturbance that the vibration of the micro oil pump may cause to the measurement of the wire pulling sensor, a spring bracket structure is designed at the bottom of the micro oil pump for vibration buffering.

[0011] Preferably, the vacuum suction cup fixing device includes a plurality of vacuum suction cups and adsorption rubber rings that match the vacuum suction cups. When the adsorption rubber rings come into contact with the smooth surface of the pressure vessel, the internal gas of the adsorption rubber rings is compacted and discharged, so that the internal air pressure of the adsorption rubber rings is lower than the external atmospheric pressure, thereby generating an internal and external pressure difference to form a surface adsorption force, and at the same time, the deformation state of the adsorption rubber rings when the air is discharged is fixed by the rubber ring sleeve and the adsorption wrench; every two vacuum suction cups are connected by a vacuum suction cup connecting plate to form a vacuum suction cup pair, and there are a total of five vacuum suction cup pairs, namely vacuum suction cup pair No. 01, vacuum suction cup pair No. 02, vacuum suction cup pair No. 03, vacuum suction cup pair No. 04, and vacuum suction cup pair No. 05.

[0012] Preferably, the vacuum suction cup pair No. 01 and the vacuum suction cup pair No. 02 are connected by the toothless screw fasteners and the toothless screw No. 01 on the vacuum suction cup connecting plate to form a fixed support structure. The toothless screw casing crosses the hard sealing end of the flexible track. The toothless screw No. 01 is passed through the toothless screw casing to fix the ultrasonic flexible track covering mechanism, and the other end is fixed in the same way. By utilizing the smoothness of the contact surface of the toothless screw No. 01 and the toothless screw casing, the ultrasonic flexible track covering mechanism can be moved along the axial direction of the toothless screw No. 01 under the action of a small lateral thrust.

[0013] Preferably, the vertical track pushing device includes a U-shaped fixing installed on the No. 03 vacuum suction cup pair, a stepper motor with an encoder is installed on one side of the U-shaped fixing, and a pusher screw, a No. 01 pusher toothless screw, and a No. 02 pusher toothless screw are installed on the other side. The rotating shaft of the stepper motor with an encoder is connected to the pusher screw through a coaxial device in the middle to form a conventional high-precision stepper motor pushing mechanism.

[0014] Preferably, the propeller screw, No. 01 propeller toothless screw, and No. 02 propeller toothless screw are connected to the propeller plate. The connection between the propeller plate and No. 01 propeller toothless screw and No. 02 propeller toothless screw is a smooth through hole, and the connection with the propeller screw is a thread. The propeller plate performs displacement movement along the axial direction of the propeller screw driven by a stepper motor with an encoder.

[0015] Preferably, the outer side of the film covering sleeve is a flexible track covering belt jacket, which is a lightweight and high-strength material of a carbon fiber plate, and the internal connection method of the flexible track covering belt jacket adopts a unit connection method; the propulsion plate and the flexible track covering belt jacket are connected by a propulsion plate connector, No. 1 adjustable bolt, No. 1 connecting rod, No. 2 adjustable bolt, No. 2 connecting rod, No. 3 adjustable bolt, jacket connector, and jacket connecting groove, wherein the jacket connecting groove is tightly bonded to the flexible track covering belt jacket, No. 1 connecting rod and No. 2 connecting rod are used to adjust the distance between the propulsion mechanism and the flexible track, No. 1 adjustable bolt, No. 2 adjustable bolt, and No. 3 adjustable bolt are used to adjust the angle between the propulsion mechanism and the flexible track, which is convenient for on-site installation and adjustment; the propulsion plate connector and the jacket connector are connecting structural parts with the propulsion plate and the jacket connecting groove at both ends of the connecting rod, respectively, and can be installed on-site.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. A new type of flexible track covering mechanism and carbon fiber linked track covering jacket design structure is proposed. The ultrasonic probe is driven to move along the track direction by the principle of fluid mechanics combined with a micro pump, which solves the problem of difficult automatic control of the ultrasonic probe moving along the arc surface of the pressure vessel;

[0018] 2. Taking full advantage of the small size and light weight of the ultrasonic probe, the flexible track covering mechanism of the ultrasonic probe and the track covering jacket connected with carbon fiber are designed to use lightweight structure and lightweight materials as much as possible, thus reducing the weight of the equipment;

[0019] 3. Based on the above, a vacuum suction cup is used for fixing, which does not require large fixed structures such as scaffolding, greatly reducing the labor intensity of the installation process;

[0020] 4. It adopts a two-dimensional fine motion control method, and can measure repeatedly, which improves the detection capability. Compared with manual detection, it greatly reduces the labor intensity caused by the harsh on-site environment and the need to repeatedly perform detection in a very small range;

[0021] 5. Some structural parts can be selected in different lengths to adapt to different equipment sites and the complexity of pressure vessel inspection and installation space caused by a large number of pipeline routes;

[0022] 6. The structural parts used in the present invention are low-cost and can be designed into various specifications;

[0023] 7. The use and maintenance requirements of the present invention are not high, and the equipment and components are not easily damaged;

[0024] 8. Compared with the ultrasonic detection solution of the adsorption trolley, there are no potential safety hazards caused by improper control, line entanglement or battery drive. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0026] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention;

[0027] Figure 2 Schematic diagram of the ultrasonic probe covering belt structure in an embodiment of the present invention;

[0028] Figure 3 It is a schematic diagram of the structure of the oil-filled sealing box and the controller in the embodiment of the present invention;

[0029] Figure 4 Schematic diagram of the structure of the vacuum suction cup fixing method in an embodiment of the present invention;

[0030] Figure 5 Schematic diagram of the structure of the axial propulsion device in an embodiment of the present invention;

[0031] Figure 6 is a schematic diagram of the structure of an ultrasonic probe in an embodiment of the present invention;

[0032] Figure 7 It is a schematic diagram of the structure during the conventional circumferential weld inspection operation;

[0033] Figure 8 It is a structural schematic diagram of the edge circumferential weld inspection operation;

[0034] Fig. 9 It is a schematic diagram of the structure during the axial weld inspection operation;

[0035] Fig.10 It is a schematic diagram of the structure of the flexible track covering with a jacket;

[0036] Figure 1 1—ultrasonic flexible track covering mechanism, 2—vacuum suction cup fixing device, 3—oil filling and pushing device along the track, 4—vertical track pushing device, 5—controller, 6—pressure vessel, 7—welding seam;

[0037] Figure 2 Among them, 101—displacement sensor cable, 102—ultrasonic detection high-frequency cable, 103—No. 01 cable penetration piece, 104—No. 01 oil pipe penetration piece, 105—No. 01 high-frequency cable penetration piece, 106—No. 02 oil pipe penetration piece, 107—hard sealing end, 108—high-frequency cable casing, 109—No. 01 oil pipe, 110—cable casing, 116—ultrasonic probe, A—section of ultrasonic flexible track covering mechanism, A111—polymer flexible track, A112—film covering sleeve, A113—oil filling, A114—track inner wall, A115—ultrasonic detection contact surface;

[0038] Figure 3 Among them, 301 is a micro oil pump, 302 is an automatic wire take-up device, 303 is a pull-wire sensor, 304 is a spring bracket, 305 is No. 02 oil pipe, 306 is No. 02 high-frequency wire through-cabin parts, 307 is No. 03 oil pipe through-cabin parts, 308 is No. 04 oil pipe through-cabin parts, 309 is No. 02 pull-wire through-cabin parts, 310 is a watertight connector of the pull-wire sensor, 311 is a watertight connector of the ultrasonic detector, 312 is a watertight connector of the micro oil pump, 313 is a control line of the pull-wire sensor, 314 is a control line of the ultrasonic detector, 315 is a control line of the micro oil pump;

[0039] Figure 4 21-01 vacuum suction cup pair, 22-02 vacuum suction cup pair, 201-adsorption rubber ring, 202-rubber ring sleeve, 203-adsorption wrench, 204-toothless screw fastener, 205-vacuum suction cup connecting plate, 206-01 toothless screw, 207-toothless screw casing;

[0040] Figure 5 401-stepping motor with encoder, 402-U-shaped fixing, 403-coaxial device, 404-thruster screw, 405-01thruster toothless screw, 406-02thruster toothless screw, 407-thruster plate, 408-No. 1 adjustable bolt, 409-No. 1 connecting rod, 410-No. 2 adjustable bolt, 411-No. 2 connecting rod, 412-No. 3 adjustable bolt, 413-jacket connector, 414-thruster plate connector, 415-jacket connecting groove, 23-03 vacuum suction cup pair, 117-flexible track covered with jacket;

[0041] Figure 6 118 - ultrasonic detection high frequency line connector, 119 - displacement sensor wire connector, 120 - limit structure, 121 - detection end face;

[0042] Figure 7 Medium 24-04 vacuum suction cup pair, 25-05 vacuum suction cup pair, 208-02 toothless screw;

[0043] Fig. 9 Middle 416—auxiliary fixing plate;

[0044] Fig.10 Middle B—enlarged partial view of the flexible track covering with jacket, B01—No. 01 covering with jacket unit, B02—No. 02 covering with jacket unit, B101—groove surface of jacket unit, B102—raised surface of jacket unit, B103—back plate of jacket unit, B104—side plate of jacket unit. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0046] The present invention provides a novel ultrasonic detection device for on-site detection of pressure vessels. First, an ultrasonic probe 116 is placed in an ultrasonic flexible track covering mechanism 1, and the two ends of the covering mechanism are tightly attached to the outer wall of a pressure vessel 6 through a vacuum suction cup fixing device 2, and the inside of the sealed track is filled with oil. A micro oil pump 301 in a track oil filling pushing device 3 is used to achieve slow displacement movement of the ultrasonic probe along the flexible track. Then, the side wall of the ultrasonic flexible track covering mechanism 1 is connected to a vertical track pushing device 4, and the thrust movement of the vertical track is provided by controlling the movement of a stepper motor, so as to achieve detection of internal cracks that may appear at the weld of the pressure vessel.

[0047] Example 1

[0048] Regarding the design of the ultrasonic flexible track coating mechanism in the present invention, refer to Figure 1 , Figure 2 and Figure 3The main body of the flexible track is a polymer flexible track A111. The selected material must have a certain structural strength to generate sufficient supporting force in the direction of the cross section A of the ultrasonic flexible track covering mechanism. At the same time, it must have a certain degree of flexibility to allow a certain bending change along the track direction to adapt to the outer wall curve of the pressure vessel. On this basis, the performance is required to be stable and will not be corroded by oil. The optional material is polytetrafluoroethylene. The outer side of A111 is completely covered by a film covering sleeve A112 to achieve complete sealing inside the track. Both ends are hard sealing ends 107, which are made of hard materials and can also be selected as polytetrafluoroethylene. They are used to connect the cabin penetration parts and the fixing rods. The flexible track is filled with oil A113, and the structure of the inner wall A114 is consistent with the outer contour of the ultrasonic detection probe 116, which allows the ultrasonic detection probe 116 to slide on the flexible track under the action of oil pressure. A115 is the contact surface for ultrasonic testing. During the testing process, the ultrasonic testing probe 116 is in close contact with the ultrasonic testing contact surface A115 under the action of the track covering, emitting sound waves in the direction of the weld of the pressure vessel 6, and receiving the sound echo reflected by the pressure vessel 6. The film covering sleeve A112 is an ultra-thin, high-elastic film structure without air impurities, and the optional materials are natural rubber, latex, nitrile and other materials. According to the principle of sound wave propagation, when the thickness of the dielectric layer is less than half of the wavelength of the sound wave, this layer of medium has almost no effect on the full transmission of the sound wave. For example, for a typical ultrasonic testing wavelength of 1.3 mm, when the film thickness is less than 0.65 mm, the effect of the film covering sleeve A112 on the transmission and propagation of the sound wave can be ignored. Therefore, this size requirement must be met during the implementation of the present invention, that is, the thickness of the film covering sleeve must be less than half the wavelength of the ultrasonic testing.

[0049] The polymer flexible track A111 is covered by the film cover A112 and connected to the track oil filling and pushing device 3 through the No. 01 pull wire through the cabin 103, the No. 01 oil pipe through the cabin 104, the No. 01 high-frequency line through the cabin 105, and the No. 02 oil pipe through the cabin through the plug-in connection 106. The two cavity structures and the connecting pipelines are all sealed and filled with oil. The detection data of the ultrasonic detection probe 116 is connected to the automatic wire take-up device 302 inside the track oil filling and pushing device 3 through the ultrasonic detection high-frequency line 102, through the No. 01 high-frequency line through the cabin 105, and under the protection of the high-frequency line casing 108, through the No. 02 high-frequency line through the cabin 306. The automatic wire take-up device 302 is connected to the controller 5 through the ultrasonic detector control line 314, so as to realize the control of the transmission wave of the ultrasonic detection probe 116 and the data collection of the receiving wave. The displacement data of the ultrasonic detection probe 116 along the track is connected to the wire sensor 303 inside the oil filling and pushing device 3 along the track through the displacement sensor wire 101, the wire insertion plug 103 No. 01, the wire sleeve 110 and the wire insertion part 309 No. 02. The wire sensor 303 is connected to the controller 5 through the wire sensor control line 313, so as to record the position of the ultrasonic detection probe 116 along the track direction and feedback the data of the position movement along this direction. The polymer flexible track A111 is covered by a film covering sleeve A112 and connected to the micro oil pump 301 through the No. 01 oil pipe penetration component 104, No. 01 oil pipe 109, and No. 04 oil pipe penetration component 308. The micro oil pump 301 then returns to the inside of the polymer flexible track A111 through the No. 03 oil pipe penetration component 307, No. 02 oil pipe 305, and No. 02 oil pipe penetration component 106, forming an internally completely sealed oil filling circuit. The micro oil pump 301 is also connected to the controller 5 through the micro oil pump watertight connector 312 and the micro oil pump control line 315. The controller 5 controls the rotation speed of the micro oil pump 301, so that the oil pressure difference at both ends of the ultrasonic detection probe 116 changes. The ultrasonic detection probe 116 can move slowly along the direction of the flexible track under the push of the oil pressure difference.

[0050] The track oil-filling pushing device 3 is an oil-filled sealed box, which mainly houses the micro oil pump 301, the automatic wire take-up device 302, and the wire pulling sensor 303, and connects the oil filling oil circuit and the line end of the ultrasonic flexible track covering mechanism 1, and the non-oil filling line end of the controller 5. In order to reduce the disturbance that the vibration of the micro oil pump 301 may cause to the measurement of the wire pulling sensor 303, a spring bracket 304 structure is designed at the bottom of the micro oil pump 301 for vibration buffering.

[0051] Example 2

[0052] The design reference of the vacuum suction cup fixing device in the present invention Figure 1 and Figure 4, mainly utilizes the compression and expulsion of the internal gas of the adsorption rubber ring 201 when it contacts the smooth surface of the pressure vessel 6, so that the internal air pressure of the rubber ring is lower than the external atmospheric pressure, thereby generating the internal and external pressure difference to form the surface adsorption force, and at the same time fixes the deformation state of the rubber ring when the air is discharged through the rubber ring sleeve 202 and the adsorption wrench 203. The two vacuum suction cups are connected by the vacuum suction cup connecting plate 205 in the middle to form the vacuum suction cup pair 21 No. 01. The material of the vacuum suction cup connecting plate 205 can be selected from high molecular polymer, aluminum alloy and other materials, and has the performance of allowing a certain slight deformation along the direction of the container wall, so that the vacuum suction cup can be in close contact with the pressure vessel wall, and at the same time has a certain rigidity along the direction 206, so that there is basically no deformation in this direction. The No. 01 vacuum suction cup pair 21 and the No. 02 vacuum suction cup pair 22 are connected by the toothless screw fastener 204 and the No. 01 toothless screw 206 on the vacuum suction cup connecting plate 205 to form a fixed support structure. The toothless screw sleeve 207 crosses the hard sealing end 107 of the flexible track. The No. 01 toothless screw 206 is passed through the toothless screw sleeve 207 to fix the ultrasonic flexible track coating mechanism 1. The other end is fixed in the same way. By utilizing the smoothness of the contact surface of the No. 01 toothless screw 206 and the toothless screw sleeve 207, the ultrasonic flexible track coating mechanism 1 can be moved along the axial direction of the No. 01 toothless screw 206 under a small lateral thrust. The ultrasonic detection fixed structure design of this vacuum suction cup pair fully utilizes the characteristics of the required load-bearing and driving ultrasonic flexible track coating mechanism 1, which is a lightweight structure with small volume and light weight, which greatly reduces the requirements for the suction cup fixed adsorption force and moving driving force.

[0053] Example 3

[0054] Regarding the design of the vertical track pushing device in the present invention, refer to Figure 1 and Figure 5A U-shaped fixing part 402 is installed on the No. 03 vacuum suction cup pair 23. A stepper motor 401 with an encoder is installed on one side of the U-shaped fixing part 402, and a propeller screw 404, a No. 01 propeller toothless screw 405, and a No. 02 propeller toothless screw 406 are installed on the other side. The rotating shaft of the stepper motor 401 is connected to the propeller screw 404 through a coaxial device 403 to form a conventional high-precision stepper motor propulsion mechanism. The propeller screw 404, the No. 01 propeller toothless screw 405, and the No. 02 propeller toothless screw 406 are connected to the propeller plate 407. The connection between the propeller plate 407 and the No. 01 propeller toothless screw 405 and the No. 02 propeller toothless screw 406 is a smooth through hole, and the connection with the propeller screw 404 is a thread, so that the propeller plate 407 can move along the axial direction of the propeller screw 404 under the drive of the stepper motor 401 with an encoder. The flexible track film cover A112 is surrounded by a flexible track jacket 117, which is a lightweight and high-strength carbon fiber plate. It is a unit connection method, which can have a certain degree of deformation along the track direction, and is a rigid connection in the vertical track direction without deformation. This ensures that when receiving the vertical track thrust, the thrust can be evenly distributed on the entire track side. The propulsion plate 407 and the flexible track covering belt jacket 117 are connected by the propulsion plate connector 414, the No. 1 adjustable bolt 408, the No. 1 link rod 409, the No. 2 adjustable bolt 410, the No. 2 link rod 411, the No. 3 adjustable bolt 412, the jacket connector 413, and the jacket connection groove 415, wherein the jacket connection groove 415 is tightly bonded to the flexible track covering belt jacket 117, the No. 1 link rod 409 and the No. 2 link rod 411 can be designed with a variety of lengths to adjust the distance between the propulsion mechanism and the flexible track, the No. 1 adjustable bolt 408, the No. 2 adjustable bolt 410, and the No. 3 adjustable bolt 412 are used for adjusting the angle between the propulsion mechanism and the flexible track, which is convenient for on-site installation and adjustment. The propulsion plate connector 414 and the jacket connector 413 are respectively the connecting structural parts at both ends of the connecting rod with the propulsion plate 407 and the jacket connection groove 415, which can be installed on-site.

[0055] Example 4

[0056] The ultrasonic probe used in the present invention is adaptively improved and designed to match the internal structure of the flexible track. Figure 6. 121 is the detection end face for ultrasonic emission and reception, which is consistent with the conventional design, but a displacement sensor wire connector 119 is added on the side wall to connect the displacement sensor wire 101 to measure the displacement of the ultrasonic probe along the flexible track. The two ends of the ultrasonic probe 116 body structure are widened, and the four corners are designed to be arc-shaped, and a limit structure 120 is added. These structural improvements are designed to match the inner wall A114 of the flexible track, so that the ultrasonic probe 116 can achieve smooth movement along the direction of the flexible track under the push of the micro oil pump 301, and will not shake in other directions. At the same time, in order to make the ultrasonic probe 116 move unimpeded along the inner wall A114 of the flexible track, the ultrasonic signal line obliquely above in the original conventional design is moved to the side, that is, the ultrasonic detection high-frequency line connector 118, and the original coaxial cable connection mode is changed to a high-frequency line connection mode, that is, the ultrasonic detection high-frequency line connector 118 is connected to the ultrasonic detection high-frequency line 102, so that the ultrasonic signal transmission line is thinner, the connection port is smaller, and the signal anti-interference ability is stronger. The above adaptive improvement design for ultrasonic probes requires customization requirements to the manufacturer, but does not require additional technical research and development, and is no different from the detection principle of the original probe.

[0057] The structure of the conventional circumferential weld inspection operation in the embodiment of the present invention is as follows: Figure 7 As shown, refer to Figure 1 , Figure 2 , Figure 5The implementation steps of on-site inspection of pressure vessels are as follows: (1) Determine the weld area to be inspected at one time according to the on-site conditions of the pressure vessel, and thereby select the length of the ultrasonic flexible track covering mechanism 1 and the flexible track covering belt jacket 117, as well as the lengths of the No. 01 toothless screw 206, the No. 02 toothless screw 208, the No. 1 connecting rod 409, and the No. 2 connecting rod 411; (2) Grind the sliding areas of the ultrasonic probe on both sides of the welder, and apply engine oil on the surface as an ultrasonic detection coupling agent; (3) Install the No. 01 vacuum suction cup pair 21, the No. 01 toothless screw 206, the No. 04 vacuum suction cup pair 24, the No. 02 toothless screw 208, the ultrasonic flexible track covering mechanism 1, the No. 02 vacuum suction cup pair 22, the No. 05 vacuum suction cup pair 25, and related accessories in sequence. Make minor adjustments to the above-mentioned installation structure to ensure that the ultrasonic flexible track coating mechanism 1 is tightly fitted to the outer wall of the pressure vessel 6, exhaust the air between the film covering sleeve A112 and the pressure vessel 6, and use the tension of the vacuum suction cup fixing device 2 and the sealing effect of the engine oil to ensure that the film covering sleeve A112 and the pressure vessel 6 are always in a tightly fitted state. Install the vertical track pusher 4 and the flexible track coating belt jacket 117, adjust the No. 1 adjustable bolt 408, No. 2 adjustable bolt 410, and No. 3 adjustable bolt 412 on the vertical track pusher 4, insert the jacket connector 413 into the jacket connection groove 415, and complete the direct connection between the vertical track pusher 4 and the ultrasonic flexible track coating mechanism 1. Connect the lines and pipelines related to the track oil filling pusher 3 and the controller 5. (4) Perform two-dimensional detection. The controller 5 controls the encoder stepper motor 401 to adjust the ultrasonic flexible track covering mechanism 1 and the weld 7 to a suitable position, fixes the encoder stepper motor 401 and keeps it unchanged, and controls the micro oil pump 301 through the controller 5, so that the ultrasonic probe 116 slides slowly from one end to the other end along the inner wall A114 of the flexible track. During this process, the controller 5 controls the ultrasonic probe 116 to transmit and receive echoes in the direction of the weld, and records the position data of the wire sensor 303 along the track direction, so as to realize the variable sliding edge detection along the track direction. In order to reduce the false detection rate and the missed detection rate, this sliding detection process can be repeated 3 to 5 times. After a detection along the track surface is completed, the micro oil pump 301 temporarily stops working, and the controller 5 controls the encoder stepper motor 401 to advance a small displacement perpendicular to the track surface and maintain it, repeating the above sliding detection process, and recording the encoder position data at the same time. Repeat the above process until the detection of the area is completed. It should be noted that in order to clearly show the structure of the detection device, the proportions of the detection device, pressure vessel and weld are adjusted in the diagram. Generally, the pressure vessel is much larger than the detection device, and the detection device performs detection in sections on the pressure vessel. (5) After completing the automatic detection of an area, plan the next weld area to be detected and repeat the above steps for detection.

[0058] The structure of the edge circumferential weld inspection operation in the embodiment of the present invention is as follows: Figure 8 As shown, the No. 02 vacuum suction cup pair 22 and the No. 05 vacuum suction cup pair 25 are installed on the left side of the ultrasonic flexible track covering mechanism 1, and the position of the ultrasonic flexible track covering mechanism 1 and the weld 7 is adjusted to achieve single-sided detection of the weld 7. Similar to manual detection, only single-sided detection can be performed on the edge circumferential weld. The other detection processes are the same as the conventional circumferential weld detection operation.

[0059] The structure of the axial weld inspection operation in the embodiment of the present invention is as follows: Fig. 9 As shown, refer to Figure 1 , Figure 5 Compared with the conventional circumferential weld inspection operation, the length of the ultrasonic flexible track covering mechanism 1 and the flexible track covering belt jacket 117 is reduced, and the length of the propeller screw 404, the No. 01 propeller toothless screw 405, the No. 02 propeller toothless screw 406, the No. 1 connecting rod 409, and the No. 2 connecting rod 411 in the vertical track pushing device 4 is increased. The length changes of all structural parts are determined by the weld inspection area. An auxiliary fixing plate 416 is added, and the auxiliary fixing plate 416 is used to stabilize the propeller screw 404, the No. 01 propeller toothless screw 405, and the No. 02 propeller toothless screw 406. The track oil filling pushing device 3 and the controller 5 are fixed to the upper part of the flexible track covering belt jacket 117, and under the action of the vertical track pushing device 4, they can move along the weld direction at the same time as the ultrasonic flexible track covering mechanism 1. Other structures are the same as those in the conventional circumferential weld inspection operation. The process of two-dimensional detection is to control the micro oil pump 301 through the controller 5 so that the ultrasonic probe 116 moves along the inner wall A114 of the flexible track to a position suitable for the distance from the weld 7, lock the driving force of the micro oil pump 301 to keep the position of the ultrasonic probe 116 in the flexible track unchanged, record the encoder position data, and the controller 5 controls the encoder stepper motor 401 to push the ultrasonic flexible track covering mechanism 1 to move along the weld direction. In this process, the controller 5 controls the ultrasonic probe 116 to transmit and receive echoes in the direction of the weld, and records the encoder position data at the same time. In order to reduce the false detection rate and missed detection rate, this reciprocating push detection process can be repeated 3 to 5 times. After that, the micro oil pump 301 pushes the ultrasonic probe 116 to slowly move a small displacement along the inner wall A114 of the flexible track, and continues to repeat the above process. Repeat the above process until the detection of the area is completed. After completing the automatic detection of an area, plan the next weld area to be detected and repeat the above steps for detection.

[0060] like Fig.10As shown in the partial enlarged view B of the flexible track covering belt jacket, the No. 01 covering belt jacket unit B01 and the No. 02 covering belt jacket unit B02 are connected together by plugging the groove surface and the convex surface. Taking the No. 02 covering belt jacket unit B02 as an example, it is composed of two jacket unit side panels B104 and a jacket unit back panel B103, all of which are lightweight and high-strength carbon fiber board materials, of which B101 and B102 are the jacket unit groove surface and the jacket unit convex surface respectively. The groove surface and the convex surface are seamlessly and tightly plugged in the vertical track direction, leaving a gap along the track direction. This design can make the entire flexible track covering belt jacket a plane along the track direction, and can have a certain degree of active bending in the vertical track direction. This structural design can meet the curvature changes of pressure vessels with different diameters.

[0061] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An ultrasonic detection device for on-site detection of large pressure vessels, characterized in that: The invention comprises an ultrasonic probe, an ultrasonic flexible track covering mechanism, a vacuum suction cup fixing device, a track oil filling and pushing device, a vertical track pushing device and a controller. The ultrasonic probe is placed in the ultrasonic flexible track covering mechanism. Both ends of the ultrasonic flexible track covering mechanism are tightly attached to the outer wall of the pressure vessel through the vacuum suction cup fixing device. The track of the ultrasonic flexible track covering mechanism is filled with oil. The micro oil pump in the track oil filling and pushing device is used to realize the slow displacement movement of the ultrasonic probe along the direction of the flexible track. The side wall of the ultrasonic flexible track covering mechanism is connected to the vertical track pushing device. The thrust movement of the vertical track is provided by controlling the movement of the stepping motor, so as to realize the detection of internal cracks that may appear at the weld of the pressure vessel.

2. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 1, characterized in that: The ultrasonic flexible track covering mechanism includes a polymer flexible track and a film covering sleeve covering the outside of the polymer flexible track, both ends of the film covering sleeve are provided with hard sealing ends, the interior of the polymer flexible track is filled with oil, the structure of its inner wall is consistent with the outer contour of the ultrasonic detection probe, and the thickness of the film covering sleeve is less than half the wavelength of the ultrasonic wave used for detection.

3. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 2, characterized in that: The polymer flexible track is covered by a film cover and connected to the track oil filling and pushing device through No. 01 wire penetration piece, No. 01 oil pipe penetration piece, No. 01 high-frequency wire penetration piece, and No. 02 oil pipe penetration piece. The cavity structure and connecting pipelines of the polymer flexible track are all sealed and filled with oil; wherein the detection data line of the ultrasonic detection probe passes through the ultrasonic detection high-frequency line, passes through the No. 01 high-frequency wire penetration piece, and under the protection of the high-frequency wire casing, passes through the No. 02 high-frequency wire penetration piece to connect with the automatic wire take-up device inside the track oil filling and pushing device, and the automatic wire take-up device is connected to the controller through the ultrasonic detector control line to realize the control of the ultrasonic detection probe's transmitting wave and the data collection of the receiving wave; the displacement data of the ultrasonic detection probe along the track is connected to the wire sensor inside the track oil filling and pushing device through the displacement sensor wire, passes through the No. 01 wire penetration piece, the wire casing, and the No. 02 wire penetration piece, and the wire sensor is connected to the controller through the wire sensor control line to realize the recording of the ultrasonic detection probe's position along the track direction and the data feedback of the position movement along this direction.

4. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 2, characterized in that: The polymer flexible track is covered by a film covering sleeve and is connected to a micro oil pump through No. 01 oil pipe penetration piece, No. 01 oil pipe, and No. 04 oil pipe penetration piece. The micro oil pump then returns to communicate with the interior of the polymer flexible track through No. 03 oil pipe penetration piece, No. 02 oil pipe, and No. 02 oil pipe penetration piece, forming an internally completely sealed oil filling circuit. The micro oil pump is also connected to a controller through a micro oil pump watertight connector and a micro oil pump control line. The controller controls the rotation speed of the micro oil pump, so that the oil pressure difference at both ends of the ultrasonic detection probe changes. The ultrasonic detection probe can move slowly along the direction of the flexible track under the push of the oil pressure difference.

5. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 4, characterized in that: The oil-filled pushing device along the track is an oil-filled sealed box, which is used to place a micro oil pump, an automatic wire take-up device, a wire pulling sensor, and connect the oil-filled oil circuit, the line end and the non-oil-filled line end of the controller of the ultrasonic flexible track covering mechanism. In order to reduce the disturbance that the vibration of the micro oil pump may cause to the measurement of the wire pulling sensor, a spring bracket structure is designed at the bottom of the micro oil pump for vibration buffering.

6. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 1, characterized in that: The vacuum suction cup fixing device includes a plurality of vacuum suction cups and adsorption rubber rings matching the vacuum suction cups. When the adsorption rubber rings contact the smooth surface of the pressure vessel, the internal gas of the adsorption rubber rings is compacted and discharged, so that the internal air pressure of the adsorption rubber rings is lower than the external atmospheric pressure, thereby generating an internal and external pressure difference to form a surface adsorption force. At the same time, the deformation state of the adsorption rubber rings when the air is discharged is fixed by the rubber ring sleeve and the adsorption wrench; every two vacuum suction cups are connected by a vacuum suction cup connecting plate to form a vacuum suction cup pair. There are five vacuum suction cup pairs in total, namely vacuum suction cup pair No. 01, vacuum suction cup pair No. 02, vacuum suction cup pair No. 03, vacuum suction cup pair No. 04 and vacuum suction cup pair No.

05.

7. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 6, characterized in that: The vacuum suction cup pair No. 01 and the vacuum suction cup pair No. 02 are connected by the toothless screw fasteners and the toothless screw No. 01 on the vacuum suction cup connecting plate to form a fixed support structure. The toothless screw sleeve crosses the hard sealing end of the flexible track. The toothless screw No. 01 is passed through the toothless screw sleeve to fix the ultrasonic flexible track covering mechanism, and the other end is fixed in the same way. By utilizing the smoothness of the contact surface of the toothless screw No. 01 and the toothless screw sleeve, the ultrasonic flexible track covering mechanism can be moved along the axial direction of the toothless screw No. 01 under the action of a small lateral thrust.

8. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 5, characterized in that: The vertical track pushing device includes a U-shaped fixing installed on the No. 03 vacuum suction cup pair, a stepper motor with an encoder is installed on one side of the U-shaped fixing, and a pusher screw, a No. 01 pusher toothless screw, and a No. 02 pusher toothless screw are installed on the other side. The rotating shaft of the stepper motor with an encoder is connected to the pusher screw through a coaxial device to form a conventional high-precision stepper motor pushing mechanism.

9. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 8, characterized in that: The propeller screw, No. 01 propeller toothless screw, and No. 02 propeller toothless screw are connected to the propeller plate. The connection between the propeller plate and No. 01 propeller toothless screw and No. 02 propeller toothless screw is a smooth through hole, and the connection with the propeller screw is a thread. The propeller plate performs displacement movement along the axial direction of the propeller screw under the drive of the stepper motor with an encoder.

10. The ultrasonic detection device for on-site detection of large pressure vessels according to claim 9, characterized in that: The outer side of the film covering sleeve is a flexible track covering belt jacket, which is a lightweight and high-strength carbon fiber plate material and adopts a unit connection method; the propulsion plate and the flexible track covering belt jacket are connected by a propulsion plate connector, No. 1 adjustable bolt, No. 1 connecting rod, No. 2 adjustable bolt, No. 2 connecting rod, No. 3 adjustable bolt, jacket connector, and jacket connecting groove, wherein the jacket connecting groove and the flexible track covering belt jacket are tightly bonded together, No. 1 connecting rod and No. 2 connecting rod are used to adjust the distance between the propulsion mechanism and the flexible track, No. 1 adjustable bolt, No. 2 adjustable bolt, and No. 3 adjustable bolt are used to adjust the angle between the propulsion mechanism and the flexible track, which is convenient for on-site installation and adjustment; the propulsion plate connector and the jacket connector are respectively connecting structural parts at both ends of the connecting rod with the propulsion plate and the jacket connecting groove, which can be installed on-site.

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