Visual array imaging near-field pulsed eddy current scanning device
By using a visual array imaging near-field pulse eddy current scanning device in an ultra-high pressure tube reactor, combined with 360° visualization technology, the problems of low detection efficiency and mechanical damage in the existing technology are solved, and rapid and precise quantities are achieved The defect detection improves detection efficiency and sensitivity.
Patent Information
- Application Number
- CN202420618057.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-28
- Publication Date
- 2024-12-06
- Estimated Expiration
- 2034-03-28
AI Technical Summary
It is difficult to effectively non-destructively detect the reaction tube parts of ultra-high pressure tube reactors, especially in high-pressure environments, and it is difficult to avoid the problems of mechanical damage and low defect identification efficiency.
The near-field pulse eddy current scanning device of visual array imaging is adopted. The array pulse eddy current imaging technology is combined with 360° visualization technology, and the support wheel and traction protective sleeve are used to achieve rapid and continuous passage, avoid mechanical damage, and improve defect detection sensitivity.
It realizes rapid and precise quantification defect detection of ultra-high pressure tube reactor reaction tubes, improves detection efficiency, avoids mechanical damage, and has the advantages of high detection sensitivity, high degree of visualization, small volume and weight, and easy to carry.
Smart Images
Figure CN222125168U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a pulse eddy current nondestructive testing technology, which is suitable for nondestructive testing of a reaction tube body of an in-service ultra-high pressure tubular reactor, and particularly relates to a visualized array imaging near-field pulse eddy current scanning device. Background Art
[0002] Ultra-high pressure tubular reactors are key core equipment in my country's million-ton ethylene production units, and are commonly found in LDPE and EVA production units. Since most of my country's ultra-high pressure tubular reactors were put into use, few non-destructive tests have been carried out on the reactor tube (i.e., inner tube) parts. The main reason is that the reactor tube parts are subjected to working pressures of 300MPa and above during in-service operation, and it is not easy to conduct shutdown inspections. In addition, the current Technical Supervision Regulations for Safety of Fixed Pressure Vessels (TSG21-2016) stipulate that ultra-high pressure tubular reactors only need to meet the general principles, materials, design, and manufacturing requirements of the regulations. For ultra-high pressure tubular reactors, especially regular inspections and regular inspections of the reactor tube parts, there are no longer mandatory requirements. Therefore, the reactor tube parts of ultra-high pressure tubular reactors are basically in the regulatory blind spot. Since ultra-high pressure tubular reactors are subjected to ultra-high pressure stresses of more than 100MPa, the inner tube parts of the reactors have undergone self-strengthening treatment to better cope with the harsh environment of ultra-high pressure bearing. However, as the reactor is put into use for a longer time, the self-enhanced stress inside the reaction tube gradually decreases. When the self-enhanced stress drops to zero, the possibility of cracking in the reaction tube will greatly increase. In addition, the raw materials used in the process of producing ethylene in some devices contain acetic acid, which will increase the possibility of local corrosion on the inner wall of the reaction tube during long-term operation. In view of this, it is very important to conduct regular and comprehensive inspections of the reaction tube parts of the ultra-high pressure tubular reactor.
[0003] The commonly used non-destructive testing methods for the inner tube of ultra-high pressure tubular reactors are endoscopic inspection or rotating eddy current testing technology. The above two methods can only detect surface defects of the inner tube, so it is difficult to meet the actual testing needs of most owners.
[0004] Pulsed eddy current testing is a branch of eddy current testing technology, which is different from conventional eddy current testing. Pulsed eddy current testing uses square wave signals as the excitation source, which has very strong penetration for ferromagnetic materials. The rich spectrum information of square wave signals can obtain more defect information, so pulsed eddy current testing technology can distinguish whether the defects of the reaction tube are located on the inner wall or the outer wall.
[0005] In the past, the pulse eddy current detection of the reaction tube of the ultra-high pressure tubular reactor mainly adopted the methods of near-field pulse eddy current and far-field pulse eddy current single probe detection, and the detection probes used were mainly conventional single-function internal penetration probes, which mainly identified defects by signal amplitude identification. Conventional internal penetration probes are generally composed of stainless steel or aluminum alloy shells and built-in detection coils. The inspector first places the detection probe into the reactor tube, and guides the probe to move in the reactor tube by pulling the protective sleeve to scan the structural integrity of the reaction tube. This is likely to cause mechanical damage to the inner wall of the reaction tube, and also easily cause damage to the probe shell, which will further destroy the structure of the coil; in addition, the single-function single-probe detection mode, once a defect is found, needs to add an endoscope to confirm the position repeatedly, which is inefficient. Summary of the invention
[0006] In view of the problems existing in the prior art, the utility model provides a visualized array imaging near-field pulsed eddy current scanning device, so that the scanning device can pass through the reaction tube quickly and continuously, greatly reducing the probability of mechanical damage caused by wear and tear of the scanning device shell and the inner tube. At the same time, the use of array pulsed eddy current imaging technology combined with 360° visualization technology effectively makes up for the shortcomings of conventional near-field pulsed eddy current and far-field pulsed eddy current probes, which can greatly improve the sensitivity of defect detection, quickly identify defect locations and achieve defect quantification.
[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a visualized array imaging near-field pulse eddy current scanning device, comprising a device body in the shape of a regular hexagon, the device body being divided into a front section and a rear section connected by a ladder seat, a support is arranged on the outer side of the hexagons at the front and rear ends of the device body, and a support wheel is installed on the support; a front end plate is installed on the end face of the front section of the device body, and a rear end plate is installed on the end face of the rear section; joints are arranged at the centers of the front end plate and the rear end plate; a connecting rod is connected to the joint of the front end plate, and a video recording device is installed on the top of the connecting rod; a traction protection sleeve is connected to the joint of the rear end plate; a signal cable of the video recording device passes through the threading hole of the front fixing plate, the array coil release hole, and the like in sequence. The through hole of the slot plate and the center line hole of the rear fixing plate are connected to the instrument host through a traction protection sleeve; a rear fixing plate is arranged on the inner side of the rear end plate, and a front fixing plate is arranged on the inner side of the front end plate, the front fixing plate and the rear fixing plate are connected by a long screw, and an array coil placement slot plate is installed between the front fixing plate and the rear fixing plate, an excitation coil placement slot is arranged in the middle of the array coil placement slot plate, and a receiving coil placement slot is arranged on the periphery of the excitation coil placement slot; an excitation coil connected to an excitation cable is installed in the excitation coil placement slot, and a receiving coil connected to a receiving cable is installed in the receiving coil placement slot; both the excitation cable and the receiving cable are connected to the instrument host through the traction protection sleeve.
[0008] Furthermore, the supporting wheel is connected to the inner wall of the reaction tube.
[0009] Furthermore, the ladder seats corresponding to the docking ports of the front section and the rear section of the device body are docked by bolts and installed on the outer side surfaces of the two opposite surfaces of the device body.
[0010] Furthermore, the traction protection sleeve is a PU steel wire reinforced hose.
[0011] Furthermore, a line connecting the front and rear corresponding supports on the outer periphery of the device body is parallel to the axis of the device body.
[0012] Furthermore, the receiving coil is composed of a circular frame and a cylindrical magnetic shielding cover shell, and the linear distance between the centers of two adjacent receiving coils is 10-15 mm.
[0013] Furthermore, there are eight receiving coil placement slots, which are evenly distributed on the array coil placement slot plate at the periphery of the excitation coil placement slot.
[0014] Furthermore, the video recording device is spherical in shape, and eight cameras are evenly distributed on the periphery.
[0015] During the detection process of the utility model, the detection personnel can guide the scanning device to move and scan inside the reaction tube by pulling the protective sleeve. During the scanning, the support wheel fits stably with the inner wall of the reaction tube, which can achieve rapid and continuous passage through the reaction tube, and realizes that the outer shell of the scanning device does not directly contact the tube wall, avoiding mechanical damage to the inner wall of the reaction tube during detection. At the same time, the array pulse eddy current imaging technology combined with 360° visualization technology is adopted to effectively make up for the shortcomings of conventional near-field pulse eddy current and far-field pulse eddy current probes, greatly improving the defect detection sensitivity; it can quickly identify the defect position of the reaction tube and realize accurate quantification of defects. It has a series of advantages such as high detection sensitivity, high degree of visualization, small size and weight, easy to carry, and simple installation and operation. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of the utility model;
[0017] Figure 2 It is a cross-sectional schematic diagram of the internal structure of the utility model;
[0018] Figure 3 It is a front view of the device body 1 of the utility model in the front direction;
[0019] Figure 4 It is a front view of the rear end direction of the device body 1 of the utility model;
[0020] Figure 5 This is a schematic diagram of the structure of the connection state of the video recording device 2 and the connecting rod 3 of the utility model;
[0021] Figure 6 for Figure 2 Schematic diagram of the AA structure;
[0022] Figure 7 It is a plan view of the front fixing plate 4 in the utility model;
[0023] Figure 8 It is a plan view of the rear fixing plate 5 in the utility model;
[0024] In the figure: 01-reaction tube, 02-instrument host; 1-device body, 11-ladder base, 12-support, 13-support wheel, 14-connector, 15-array coil placement slot plate, 151-excitation coil placement slot, 152-receiving coil placement slot, 153-through hole; 16-front end plate, 17-rear end plate; 2-video recording device, 3-connecting rod, 4-front fixing plate, 41-threading hole; 5-rear fixing plate, 51-center line hole; 6-receiving coil, 7-excitation coil, 8-traction protection sleeve, 9-signal cable, 10-excitation cable, 101-receiving cable. DETAILED DESCRIPTION
[0025] The utility model is further described below in conjunction with the accompanying drawings and embodiments. Figures 1 to 8 , a near-field pulse eddy current scanning device for visualization array imaging includes a device body 1 in the shape of a regular hexagon, the device body 1 is divided into a front section and a rear section connected by a ladder seat 11, and the ladder seats 11 corresponding to the docking ports of the front section and the rear section of the device body 1 are docked by bolts and installed on the outer side surfaces of the two opposite surfaces of the device body 1. Supports 12 are arranged on the outer side of the hexagons at the front and rear ends of the device body 1, and the connecting line between the supports 12 corresponding to the front and rear ends of the periphery of the device body 1 is parallel to the axis of the device body 1, and support wheels 13 are installed on the supports 12. The support wheels 13 are connected to the inner wall of the reaction tube 01. A front end plate 16 is installed on the end face of the front section of the device body 1, and a rear end plate 17 is installed on the end face of the rear section; a joint 14 is arranged at the center of the front end plate 16 and the rear end plate 17; the joint 14 of the front end plate 16 is connected to a connecting rod 3, and a video recording device 2 is installed on the top of the connecting rod 3. The video recording device 2 is spherical, and eight cameras are evenly arranged on the periphery. The connector 14 of the rear end plate 17 is connected to a traction protection sleeve 8 (such as Figure 1 and Figure 2As shown in the figure, the traction protection sleeve 8 is a PU steel wire reinforced hose. The signal cable 9 of the video recording device 2 passes through the threading hole 41 of the front fixing plate 4, the through hole 153 of the array coil placement slot plate 15 and the center line hole 51 of the rear fixing plate 5 in sequence and is connected to the instrument host 02 through the traction protection sleeve 8; the rear fixing plate 5 is arranged on the inner side of the rear end plate 17, and the front fixing plate 4 is arranged on the inner side of the front end plate 16. The front fixing plate 4 and the rear fixing plate 5 are connected by a long screw, and an array coil placement slot plate 15 is installed between the front fixing plate 4 and the rear fixing plate 5. An excitation coil placement slot 151 is arranged in the middle of the array coil placement slot plate 15, and a receiving coil placement slot 152 is arranged on the periphery of the excitation coil placement slot 151. There are eight receiving coil placement slots 152, which are evenly distributed on the array coil placement slot plate 15 on the periphery of the excitation coil placement slot 151. The excitation coil placement slot 151 is equipped with an excitation coil 7 connected to an excitation cable 10, and the receiving coil placement slot 152 is equipped with a receiving coil 6 connected to a receiving cable 101. The receiving coil 6 is composed of a circular skeleton and a cylindrical magnetic shielding cover shell, and the linear distance between the centers of two adjacent receiving coils is 10-15 mm. The excitation cable 10 and the receiving cable 101 are both connected to the instrument host 02 (such as Figures 2 to 8 as shown). Example
[0026] The utility model visualized array imaging near-field pulse eddy current scanning device has an overall structure of a detachable regular hexagonal device body 1 with two front and rear sections. The front end plate 16 of the front section of the device body 1 is provided with a joint 14 with a central through hole, and the rear section of the device body 1 is provided with a rear end plate 17, which is also provided with a joint 14. Six pairs of supports 12 are fixedly welded on the periphery of the device body 1 with hot melt, and each pair of two supports 12 is a pair, and the connecting line between the two supports 12 is parallel to the axis of the device body 1. Wheel frames are respectively installed on the supports 12 by bolts, and each wheel frame is installed with a driving wheel 13 (such as Figure 1 and Figure 2 The front end plate 16 and the rear end plate 17 of the device body 1 are fixed by screws through the through holes with internal threads distributed at the six corners of the regular hexagon (as shown in FIG. Figure 3 and Figure 4 as shown).
[0027] The video recording device 2 is a spherical structure, with eight pinhole high-definition cameras (model: M12-16IR (5MP)) evenly distributed around the outside, and the high-definition cameras are connected to a signal cable 9 provided inside. A tubular joint with external threads is fixed by welding on the side of the video recording device 2 near the connecting rod 3, and the tubular joint is connected to the internal threads of the connecting rod 3. The connecting rod 3 is inserted into the joint 14 of the front end plate 16 of the device body 1 and fixed by a nut (see Figure 5). The array detection coil is composed of an array coil placement slot plate 15, a front fixing plate 4, a rear fixing plate 5, eight receiving coils 6, an excitation coil 7, an excitation cable 10 and a receiving cable 101. The array coil placement slot plate 15 is integrally formed with the rear section of the device body 1 through 3D printing. The receiving coil 6 is composed of a circular plastic frame, an enameled wire wrapped around its outside and an external cylindrical magnetic shield. The excitation coil 7 is composed of a cylindrical magnetic core and an enameled wire wrapped around its outside. Every 1 / 3 turn of the enameled wire is fixed with glue. The receiving coil 6 and the excitation coil 7 are respectively placed in the excitation coil placement slot 151 and the receiving coil placement slot 152, and the signal receiving lines led out of the eight receiving coils 6 are integrated and connected to a receiving cable 101. The wires led out of the excitation coil 7 are connected to an excitation cable 10 (such as Figure 2 As shown in FIG. 1 ), the receiving coil 6 and the exciting coil 7 in the array coil placement slot plate 15 are fixed by installing screws on four internal threaded through holes on the front fixing plate 4 and the rear fixing plate 5 (see FIG. 1 ). Figures 6 to 8 ). The receiving cable 101 and the exciting cable 10 pass through the centerline hole 51 of the rear fixing plate 5, the connector 14 and the traction protection sleeve 8 to be connected to the excitation and receiving ends of the instrument host 02 (CHPEC-1 pulse eddy current detector); the signal cable 9 led out of the video recording device 2 passes through the threading hole 41 of the front fixing plate 4, the through hole of the array coil placement slot plate 15 and the centerline hole 51 of the rear fixing plate 5, and then is connected to the video imaging connection port of the instrument host 02 through the connector 14 and the traction protection sleeve 8. The connector 14 of the rear end plate 17 is fixedly connected to the traction protection sleeve 8 by plastic welding.
[0028] In order to achieve fast and efficient all-round imaging detection of in-service ultra-high pressure tubular reactors, eight receiving coils 6 are evenly distributed around the outer circumference of the cylindrical excitation coil 7. According to the results of simulation and combined experiments, the detection sensitivity is best when the straight-line distance between the centers of two adjacent receiving coils 6 is set to 10-15 mm.
[0029] When the utility model is used, the reaction tube 01 of the ultra-high pressure tubular reactor to be inspected is first cleaned with high-pressure water to remove the polyethylene powder remaining on the surface of the reaction tube 01 as much as possible. After cleaning, the visualization array imaging near-field pulse eddy current scanning device is placed in the reaction tube 01 as a whole, so that the twelve support wheels 13 are in supporting contact with the inner surface of the reaction tube 01, and the movement position of the device body 1 in the reaction tube 01 is controlled by the traction protection sleeve 8. During the movement, it is necessary to avoid the stepping speed of the scanning device body 1 being greater than 150mm / s. During the scanning process, pay attention to the color change area of the B scan or C scan of the pulse eddy current array imaging. Once an abnormal signal part is found, it should be observed in time in combination with the video recording device 2, and if necessary, take photos and keep records through the video recording device 2.
[0030] The model of the pulse eddy current instrument host 02 in the utility model is: CHPEC-1. The device body 1, the ladder seat 11, the support 12, the support wheel 13, the array coil placement slot plate 15, the joint 14, the front fixing plate 4, the rear fixing plate 5, the front plate 16, the rear plate 17, and the connecting rod 3 are made of thermoplastic polyester or polycarbonate engineering plastics. The magnetic core in the excitation coil 7 is made of cylindrical hollow ferrite magnetic concentrator material. The cylindrical magnetic shield in the receiving coil 6 is made of Permalloy, and the thickness is preferably selected to be 0.2mm~0.5mm. The circular skeleton in the receiving coil 6 and other nuts and screws used for fixing, the wheel frame, etc. are made of PC material. The diameter of the enameled wire in the excitation coil 7 is preferably selected to be 0.5mm~1.0mm, and the diameter of the enameled wire in the receiving coil 6 is preferably selected to be 0.2mm~0.4mm.
[0031] The utility model can realize fast 360° imaging detection of defects such as local corrosion and cracks existing in the reaction tube 01 of the ultra-high pressure tubular reactor in service. Compared with the traditional single-probe internal penetration eddy current detection scanning device, it can realize fast quantification and positioning of cracks with a length of 10mm and a depth of 1mm or more, or local corrosion with a circumferential diameter of Φ25mm and a depth of 1mm or more, and mechanical damage pit defects on the inner wall 01 of the reaction tube. It is easy to operate and improves the detection efficiency by 1.5 times. At the same time, the utility model has the function of quickly passing through corrosion pits and bending deformation parts, avoiding direct friction between the outer shell of the scanning device and the inner wall of the reaction tube 01, ensuring that the inner wall of the detected reaction tube 01 will not be mechanically damaged due to the detection, and has a series of advantages such as high detection sensitivity, high visualization, small size and weight, and easy to carry.
Claims
1. Visual array imaging near-field pulsed eddy current scanning device, characterized in that: The device body (1) comprises a regular hexagonal device body, wherein the device body (1) is divided into a front section and a rear section connected by a ladder seat (11); a support (12) is arranged on the outer side of the hexagons at the front and rear ends of the device body (1), and a support wheel (13) is installed on the support (12); a front end plate (16) is installed on the end face of the front section of the device body (1), and a rear end plate (17) is installed on the end face of the rear section; a joint (14) is arranged at the center of the front end plate (16) and the rear end plate (17); the joint (14) of the front end plate (16) is connected to a connecting rod (3), and a video recording device (2) is installed at the top of the connecting rod (3); the joint (14) of the rear end plate (17) is connected to a traction protection sleeve (8); a signal cable (9) of the video recording device (2) passes through the threading hole (41) of the front fixing plate (4), the through hole (153) of the array coil placement slot plate (15), and the center line hole (51) of the rear fixing plate (5) in sequence. ) is connected to the instrument host (02) via a traction protection sleeve (8); a rear fixing plate (5) is arranged on the inner side of the rear end plate (17), and a front fixing plate (4) is arranged on the inner side of the front end plate (16); the front fixing plate (4) and the rear fixing plate (5) are connected via a long screw, and an array coil placement slot plate (15) is installed between the front fixing plate (4) and the rear fixing plate (5); an excitation coil placement slot (151) is arranged in the middle of the array coil placement slot plate (15), and a receiving coil placement slot (152) is arranged on the periphery of the excitation coil placement slot (151); an excitation coil (7) connected to an excitation cable (10) is installed in the excitation coil placement slot (151), and a receiving coil (6) connected to a receiving cable (101) is installed in the receiving coil placement slot (152); the excitation cable (10) and the receiving cable (101) are both connected to the instrument host (02) via the traction protection sleeve (8).
2. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: The supporting wheel (13) is connected to the inner wall of the reaction tube (01).
3. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: The ladder seats (11) correspondingly installed at the docking ports of the front section and the rear section of the device body (1) are docked by bolts and installed on the outer side surfaces of two opposite surfaces of the device body (1).
4. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: The traction protection sleeve (8) is a PU steel wire reinforced hose.
5. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: The connecting line between the front and rear corresponding supports (12) on the outer periphery of the device body (1) is parallel to the axis of the device body (1).
6. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: The receiving coil (6) is composed of a circular frame and a cylindrical magnetic shielding cover shell, and the linear distance between the centers of two adjacent receiving coils is 10-15 mm.
7. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: There are eight receiving coil placement slots (152) uniformly distributed on the array coil placement slot plate (15) at the periphery of the excitation coil placement slot (151).
8. The visual array imaging near-field pulsed eddy current scanning device according to claim 1, characterized in that: The video recording device (2) is spherical in shape, and has eight cameras evenly distributed around its periphery.