A system for detecting bulging and pits of a heating surface tube

Abstract

The utility model relates to a boiler detection technical field discloses a kind of heating surface tube expansion and pit detection systems, comprising: multiple positioning needle encircles heating surface tube and is in channel through;Positioning needle and channel are all directed to center;Elastic member is fixed on positioning needle, and elastic member one end is fixed on intermediate frame, and other end is abutted on elastic limiting frame;Heating surface tube expansion and pit detection system has elastic member abutted on elastic limiting frame, and the non-detection state that positioning needle inner end is not contacted with heating surface tube;And have pressed down elastic limiting frame, remove the restriction to elastic member, and elastic member drives positioning needle inner end abutted on heating surface tube outer wall, and utilize vernier caliper to detect the detection state of the distance between two positioning needle outer ends.The application is accurately positioned to the outer wall of heating surface tube by relative positioning needle, realize accurate measurement to the diameter of heating surface tube, accurately judge the expansion and pit condition of heating surface tube, facilitate the anti-abrasion and anti-explosion inspection work of boiler.

Description

Technical Field

[0001] This utility model relates to the field of boiler testing technology, specifically to a system for detecting tube expansion and dents on heated surfaces. Background Technology

[0002] The heating surface tubes of the boiler are used in a high temperature and high pressure environment for a long time. Under the combined action of factors such as smoke, water vapor, high temperature and external stress, the surface condition and microstructure of the heating surface tubes gradually deteriorate. In severe cases, it can lead to dangerous defects such as creep and bulging of the outer diameter of the weak parts of the heating surface tubes. These dangerous defects can then rapidly expand and cause serious accidents, seriously affecting the safe, economic and environmental operation of the boiler unit.

[0003] According to the "Boiler Safety Technical Regulations" TSG11 According to the 2020 regulations, the high-temperature section heating surface tubes of superheaters and reheaters must undergo an inspection for bulging. This is in accordance with the "Technical Supervision Regulations for Metals in Thermal Power Plants" DL / T438. According to the 2016 regulations, heating surface tubes should be replaced promptly when the outer diameter creep of low alloy steel heating surface tubes exceeds 2.5%, carbon steel heating surface tubes exceed 3.5%, T91 and T122 type heating surface tubes exceed 1.2%, and austenitic heat-resistant steel heating surface tubes exceed 4.5%.

[0004] Furthermore, after prolonged use, the brittleness of some austenitic steel heat-receiving tubes increases, and even small dents can cause microcracks in the tube wall; these microcracks are difficult to detect directly on-site. According to test results, for some austenitic steel heat-receiving tubes, the probability of microcrack formation increases significantly when dents reach a certain size. Therefore, inspection of the heat-receiving tubes is essential.

[0005] In existing technologies, inspectors often only use vernier calipers to check the creep and bulging of the outer diameter of the heating surface tube. However, because the shape of the heating surface tube changes after local bulging, it is difficult to accurately position the measuring end of the vernier caliper at the circumference to be measured. Furthermore, there is currently no effective solution for detecting the location of pits after they appear on the outside of the heating surface tube, resulting in inaccurate diameter readings at the circumference to be measured. This brings many difficulties to the boiler's anti-wear and explosion-proof inspection work. Utility Model Content

[0006] In view of this, the present invention provides a heating surface tube expansion and pit detection system to solve the problem that current inspection personnel often only use vernier calipers to detect the outer diameter creep and expansion of the heating surface tube. Because the shape of the heating surface tube changes after local expansion, it is difficult for the measuring end of the vernier caliper to accurately locate the circumference of the heating surface tube to be measured. Furthermore, there is currently no effective solution for detecting the location of pits after they appear on the outside of the heating surface tube, resulting in inaccurate diameter at the circumference of the heating surface tube to be measured, which brings many difficulties to the anti-wear and explosion-proof inspection of the boiler.

[0007] This utility model provides a system for detecting tube bulging and pitting on heated surfaces, including: The clamping structure is suitable for clamping heated surface tubes; Two semi-annular detection plates are detachably fixed to the clamping structure; and after the two semi-annular detection plates are detachably connected and enclosed to form a complete ring, they are arranged at intervals around the heated surface tube; the ring surface of the complete ring is perpendicular to the axial direction of the heated surface tube. Two semi-circular outer frames are arranged to form a first ring on the two semi-circular detection plates, and the first ring is concentric with the whole ring. Two semi-circular intermediate frames are arranged to form a second ring on the two semi-circular detection plates. The second ring is located inside the first ring and is concentric with the entire ring. Two semi-circular elastic limiting frames are joined together to form a third ring on the two semi-circular detection plates. The third ring is located inside the second ring and is concentrically arranged with the entire ring. Two semi-circular inner frames are joined together to form a fourth ring, which is set on the two semi-circular detection plates. The fourth ring is located inside the third ring and is concentric with the entire ring. Multiple positioning pins are arranged around the heated surface tube and pass through an even number of channels; the channels are formed by holes that pass through the middle frame, the elastic limiting frame and the inner frame; the positioning pins and the channels are all set towards the center of the entire ring; two positioning pins that are spaced apart are located on the same straight line; and the even number of channels are evenly distributed. Multiple elastic elements are fixedly mounted on multiple positioning pins. One end of each elastic element is fixed to the outer wall of the middle frame, and the other end of each elastic element abuts against the inner wall of the elastic limiting frame. A vernier caliper with two measuring ends suitable for measuring the distance between the outer ends of two opposing positioning pins; The heating surface tube expansion and pit detection system has two states: a non-detection state where an elastic element abuts against the inner wall of the elastic limiting frame, and the inner end of the positioning pin is not in contact with the outer wall of the heating surface tube; and a detection state where pressing down the two elastic limiting frames releases the restriction on the other end of the elastic element, causing the inner end of the positioning pin to abut against the outer wall of the heating surface tube, and a vernier caliper is used to measure the distance between the outer ends of the two opposing positioning pins. Beneficial effects: This application adopts the above technical solution, using opposing positioning pins abutting against the uneven heating surface tube to accurately position the outer wall of the heating surface tube, thereby achieving accurate measurement of the diameter of the heating surface tube, and accurately judging the expansion and pitting condition of the heating surface tube, which is beneficial for the anti-wear and explosion-proof inspection of the boiler; and the fact that the entire ring surface is perpendicular to the axial direction of the heating surface tube ensures the accuracy of diameter detection.

[0008] Optionally, for each channel, an angle value is marked on the outer frame. Beneficial effect: By adopting the above technical solution, the circumferential position can be determined, thereby enabling accurate measurement of the diameter at different circumferential positions of the heated surface tube.

[0009] Optionally, the number of channels is 36, and the angle between two adjacent channels is 5°.

[0010] Optionally, the elastic element is a spring.

[0011] Optionally, it also includes: The first and second enlarged detection rings have one end connected to the two detection ends of the vernier caliper, respectively. The other ends of the first and second enlarged detection rings are adapted to contact the outer ends of the two positioning pins, respectively. When the moving detection end of the vernier caliper is in contact with the fixed detection end, the distance between the other ends of the first and second enlarged detection rings is the same as the sum of the lengths of the two positioning pins. Beneficial effect: By adopting the above technical solution, the diameter of the circumference to be measured on the heated surface tube can be directly read from the vernier caliper without unnecessary calculations, reducing the workload of the inspectors and significantly improving the efficiency of diameter measurement.

[0012] Optionally, the clamping structure includes: Two semi-annular trays, after being detachably connected and enclosed, are arranged to surround and clamp the heated surface tube; the annular surfaces of the two semi-annular trays are perpendicular to the axial direction of the heated surface tube; two semi-annular detection plates are detachably fixed to the annular surfaces of the two semi-annular trays. A fixed frame, wherein a semi-circular tray is fixed to the fixed frame by a connector; and a first slide rail perpendicular to each other is provided on the fixed frame. A movable frame is provided, and another semi-annular tray is fixed to the movable frame via a connector. Two sliders are provided on the movable frame, each slider being slidably connected to two first slide rails. Bolts are threaded onto the sliders, and the screwing ends of the bolts are adapted to screw into bolt holes provided on the fixed frame. The clamping structure is adapted to tighten the bolts, causing the sliders to slide in the first slide rails, thereby moving the movable frame and adjusting the relative positions of the fixed frame and the movable frame, and consequently adjusting the relative positions of the two semi-annular trays. Beneficial effect: This application adopts the above technical solution, ensuring the accuracy of diameter detection by ensuring that the annular surfaces of the two semi-annular trays are perpendicular to the axial direction of the heated surface tube.

[0013] Optionally, a second slide rail perpendicular to each other is provided on the movable frame, and a slider is fixedly provided in the second slide rail.

[0014] Optionally, the two semi-circular trays can be detachably connected by snap-fit.

[0015] Optionally, the two semi-circular detection plates are connected by a magnet.

[0016] Optionally, the two semi-annular detection pieces can be detachably fixed to the clamping structure via a magnetic connection structure. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a partial front view schematic diagram of the clamping structure provided in the embodiment of this utility model; Figure 2 This is a top view of the tray structure provided in the embodiment of this utility model; Figure 3 This is a top view of the fixed frame provided in the embodiment of the present utility model; Figure 4 This is a schematic diagram of the main view structure of the movable frame provided in the embodiment of this utility model; Figure 5 This is a bottom view of the movable frame provided in the embodiment of this utility model. Figure 6 This is a partial top view of the heating surface tube expansion and pit detection system provided in this embodiment of the utility model. Figure 1 ; Figure 7This is a partial top view of the heating surface tube expansion and pit detection system provided in this embodiment of the utility model. Figure 2 .

[0019] Explanation of reference numerals in the attached figures: 1. Tray; 2. Buckle; 3. Fixing frame; 4. First slide rail; 5. Bolt hole; 6. Slider; 7. Bolt; 8. Second slide rail; 9. Moving frame; 10. Detection plate; 11. Positioning pin; 12. Outer frame; 13. Middle frame; 14. Inner frame; 15. Elastic limiting frame; 16. Heated surface tube; 17. Vernier caliper; 18. First enlarged detection ring; 19. Second enlarged detection ring; 20. Elastic element; 21. Connecting element. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] like Figures 1 to 7 A specific embodiment of the heating surface tube bulging and dent detection system shown includes: a clamping structure, two semi-annular detection plates 10, two semi-annular outer frames 12, two semi-annular middle frames 13, two semi-annular elastic limiting frames 15, two semi-annular inner frames 14, multiple positioning pins 11, multiple elastic elements 20, and a vernier caliper 17. The heating surface tube bulging and dent detection system described in this application is suitable for accurately detecting the diameter of the heating surface tubes 16 of boilers used in thermal power plants at multiple circumferential positions, thereby determining the creep and damage conditions of the heating surface tubes 16.

[0022] like Figure 6 and Figure 7As shown, the clamping structure is adapted to clamp the heated surface tube 16. Two semi-annular detection plates 10 are detachably fixed to the clamping structure; and after the two semi-annular detection plates 10 are detachably connected and enclosed to form a complete ring, they are arranged at intervals around the heated surface tube 16; the annular surface of the complete ring is perpendicular to the axial direction of the heated surface tube 16. Two semi-annular outer frames 12 are arranged to form a first ring on the two semi-annular detection plates 10, and the first ring is concentric with the complete ring. Two semi-annular middle frames 13 are arranged to form a second ring on the two semi-annular detection plates 10, the second ring is located inside the first ring; and the second ring is concentric with the complete ring. Two semi-annular elastic limiting frames 15 are arranged to form a third ring on the two semi-annular detection plates 10, the third ring is located inside the second ring; and the third ring is concentric with the complete ring. Two semi-circular inner frames 14 are arranged to form a fourth ring on the two semi-circular detection plates 10. The fourth ring is located inside the third ring and is concentric with the entire ring. Multiple positioning pins 11 surround the heated surface tube 16 and pass through an even number of channels. The channels are formed by holes passing through the intermediate frame 13, the elastic limiting frame 15, and the inner frame 14. The positioning pins 11 and the channels all point towards the center of the entire ring. Two positioning pins 11 spaced apart are located on the same straight line. The even number of channels are evenly distributed. Multiple elastic elements 20 are fixedly mounted on the multiple positioning pins 11. One end of the elastic element 20 is fixed to the outer wall of the intermediate frame 13, and the other end of the elastic element 20 abuts against the inner wall of the elastic limiting frame 15. The elastic element 20 is in a compressed state. The two detection ends of the vernier caliper 17 are adapted to detect the distance between the outer ends of two opposite positioning pins 11. The heating surface tube expansion and dent detection system has two states: a non-detection state where an elastic element 20 abuts against the inner wall of the elastic limiting frame 15, and the inner end of the positioning pin 11 is not in contact with the outer wall of the heating surface tube 16; and a detection state where two elastic limiting frames 15 are pressed down, releasing the restriction on the other end of the elastic element 20, causing the elastic element 20 to drive the inner end of the positioning pin 11 to abut against the outer wall of the heating surface tube 16, and a vernier caliper 17 is used to detect the distance between the outer ends of the two opposing positioning pins 11. In the detection state, the outer end of the positioning pin 11 always extends beyond the outside of the intermediate frame 13. The difference between the distance between the outer ends of the two opposing positioning pins 11 detected by the vernier caliper 17 and the sum of the lengths of the two positioning pins 11 is the diameter of the heating surface tube 16 in the direction of the corresponding two positioning pins 11. The heating surface tube expansion and dent detection system of this application can detect the diameter of the heating surface tube 16 in different directions of the two opposing positioning pins 11 multiple times.

[0023] Furthermore, the number of channels is 36, and the angle between two adjacent channels is 5°.

[0024] Specifically, the elastic element 20 is a spring.

[0025] Furthermore, the heating surface tube expansion and dent detection system described in this application further includes: a first enlarged detection ring 18 and a second enlarged detection ring 19. One end of the first enlarged detection ring 18 and the second enlarged detection ring 19 are respectively connected to the two detection ends of the vernier caliper 17, and the other end of the first enlarged detection ring 18 and the second enlarged detection ring 19 is adapted to contact the outer ends of the two positioning pins 11 respectively; when the moving detection end of the vernier caliper 17 is in contact with the fixed detection end, the distance between the other ends of the first enlarged detection ring 18 and the second enlarged detection ring 19 is the same as the sum of the lengths of the two positioning pins 11. When the moving detection end of the vernier caliper 17 is in contact with the fixed detection end, the vernier caliper 17 is in a zero-state. When detecting the diameter of the heating surface tube 16, the reading on the vernier caliper 17 is the diameter value of the heating surface tube 16.

[0026] Specifically, such as Figures 1 to 5 As shown, the clamping structure includes: two semi-annular trays 1, a fixed frame 3, and a movable frame 9. The two semi-annular trays 1, after being detachably connected and enclosed, surround and clamp the heated surface tube 16; the annular surfaces of the two semi-annular trays 1 are perpendicular to the axial direction of the heated surface tube 16; two semi-annular detection plates 10 are detachably fixed to the annular surfaces of the two semi-annular trays 1. One semi-annular tray 1 is fixed to the fixed frame 3 by a connector 21; the fixed frame 3 is provided with mutually perpendicular first slide rails 4. The other semi-annular tray 1 is fixed to the movable frame 9 by a connector 21; the movable frame 9 is provided with two sliders 6, which are slidably connected to the two first slide rails 4 respectively; enabling the movable frame 9 to move freely relative to the fixed frame 3 in the horizontal direction. A bolt 7 is threaded onto the slider 6, and the screwing end of the bolt 7 is adapted to be screwed into the bolt hole 5 provided on the fixed frame 3; the clamping structure is adapted to screw the bolt 7, thereby driving the slider 6 to slide in the first slide rail 4, driving the moving frame 9 to move, adjusting the relative position of the fixed frame 3 and the moving frame 9, and thus adjusting the relative position of the two semi-annular trays 1.

[0027] Specifically, such as Figure 4 and Figure 5 As shown, a second slide rail 8 perpendicular to each other is provided on the movable frame 9, and a slider 6 is fixedly provided inside the second slide rail 8.

[0028] Specifically, such as Figure 1 and Figure 2 As shown, the two semi-circular trays 1 are detachably connected by snap fasteners 2.

[0029] Specifically, the two semi-circular detection pieces 10 are connected by a magnet.

[0030] Specifically, the two semi-annular detection pieces 10 are detachably fixed to the clamping structure via a magnetic connection structure.

[0031] The heating surface tube bulging and dent detection system described in this application accurately measures the diameter of the heating surface tube 16, facilitating precise judgment of the bulging condition and trend of the heating surface tube 16. This is particularly crucial for determining the creep variation of the martensitic stainless steel heating surface tube 16. The system also accurately measures the diameter of the heating surface tube 16 and assesses any wall impacts, accurately understanding the influence of impacts and dents on the heating surface tube 16. This system can be used with relatively large dimensions to measure the diameter of various heating surface tubes 16, adapting to the measurement needs of the vast majority of heating surface tubes 16.

[0032] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by this application.

Claims

1. A system for detecting bulging and pitting of heated surface tubes, characterized in that, include: Clamping structure, suitable for clamping heated surface tube (16); Two semi-annular detection plates (10) are detachably fixed to the clamping structure; and after the two semi-annular detection plates (10) are detachably connected and enclosed to form a complete ring, they are arranged at intervals around the heated surface tube (16); the ring surface of the complete ring is perpendicular to the axial direction of the heated surface tube (16); Two semi-circular outer frames (12) are arranged to form a first ring on the two semi-circular detection pieces (10), and the first ring is concentric with the whole ring. Two semi-circular intermediate frames (13) are arranged to form a second ring on the two semi-circular detection pieces (10). The second ring is located inside the first ring and is concentric with the entire ring. Two semi-circular elastic limiting frames (15) are arranged to form a third ring on the two semi-circular detection plates (10). The third ring is located inside the second ring and is concentric with the whole ring. Two semi-circular inner frames (14) are arranged to form a fourth ring on the two semi-circular detection pieces (10). The fourth ring is located inside the third ring and is concentric with the whole ring. Multiple positioning pins (11) are arranged around the heated surface tube (16) and pass through an even number of channels. The channels are formed by holes that pass through the middle frame (13), the elastic limiting frame (15) and the inner frame (14). The positioning pins (11) and the channels are all set to point towards the center of the entire ring. Two positioning pins (11) that are spaced apart are located on the same straight line. The even number of channels are evenly distributed. Multiple elastic elements (20) are fixedly mounted on multiple positioning pins (11). One end of the elastic element (20) is fixed on the outer wall of the middle frame (13), and the other end of the elastic element (20) abuts against the inner wall of the elastic limiting frame (15). Vernier caliper (17), with two measuring ends adapted to measure the distance between the outer ends of two opposing positioning pins (11); The heating surface tube expansion and dent detection system has a non-detection state where the elastic element (20) abuts against the inner wall of the elastic limiting frame (15) and the inner end of the positioning pin (11) does not contact the outer wall of the heating surface tube (16); and a detection state where pressing down the two elastic limiting frames (15) releases the restriction on the other end of the elastic element (20), the elastic element (20) drives the inner end of the positioning pin (11) to abut against the outer wall of the heating surface tube (16), and the distance between the outer ends of the two opposing positioning pins (11) is detected by a vernier caliper (17).

2. The heating surface tube expansion and pit detection system according to claim 1, characterized in that, For each channel, an angle value is marked on the outer frame (12).

3. The heating surface tube expansion and pit detection system according to claim 2, characterized in that, The number of channels is 36, and the angle between two adjacent channels is 5°.

4. The heating surface tube expansion and pit detection system according to claim 1, characterized in that, The elastic element (20) is a spring.

5. The system for detecting tube bulging and pitting on heated surfaces according to any one of claims 1-4, characterized in that, Also includes: The first enlarged detection ring (18) and the second enlarged detection ring (19) are connected at one end to the two detection ends of the vernier caliper (17), and the other ends of the first enlarged detection ring (18) and the second enlarged detection ring (19) are adapted to contact the outer ends of the two positioning pins (11), respectively. When the moving detection end of the vernier caliper (17) is in contact with the fixed detection end, the distance between the other ends of the first enlarged detection ring (18) and the second enlarged detection ring (19) is the same as the sum of the lengths of the two positioning pins (11).

6. The heating surface tube expansion and pitting detection system according to any one of claims 1-4, characterized in that, The clamping structure includes: Two semi-annular trays (1) are detachably connected and enclosed, and are arranged to surround and clamp the heated surface tube (16); the annular surface of the two semi-annular trays (1) is perpendicular to the axial direction of the heated surface tube (16); two semi-annular detection plates (10) are detachably fixed to the annular surface of the two semi-annular trays (1). A fixed frame (3) is provided, in which a semi-circular tray (1) is fixed to the fixed frame (3) by a connector (21); a first slide rail (4) perpendicular to each other is provided on the fixed frame (3); The movable frame (9) and the other semi-circular tray (1) are fixed on the movable frame (9) by a connector (21); two sliders (6) are provided on the movable frame (9), and the two sliders (6) are slidably connected to two first slide rails (4) respectively; a bolt (7) is threaded on the slider (6), and the screwing end of the bolt (7) is adapted to be screwed into the bolt hole (5) provided on the fixed frame (3); the clamping structure is adapted to screw the bolt (7), drive the slider (6) to slide in the first slide rail (4), drive the movable frame (9) to move, adjust the relative position of the fixed frame (3) and the movable frame (9), and then adjust the relative position of the two semi-circular trays (1).

7. The heating surface tube expansion and pit detection system according to claim 6, characterized in that, A second slide rail (8) perpendicular to each other is provided on the moving frame (9), and a slider (6) is fixedly provided inside the second slide rail (8).

8. The heating surface tube expansion and pit detection system according to claim 6, characterized in that, Two semi-circular trays (1) are detachably connected by snaps (2).

9. The system for detecting tube bulging and pitting on heated surfaces according to any one of claims 1-4, characterized in that, Two semi-circular detection plates (10) are connected by a magnet.

10. The system for detecting tube bulging and pitting on heated surfaces according to any one of claims 1-4, characterized in that, Two semi-circular detection pieces (10) are detachably fixed to the clamping structure via a magnetic connection structure.

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