Single-girder crane I-beam failure detection device

Abstract

The application provides a single-main-girder hoisting machinery I-beam failure detection device, and belongs to the technical field of I-beam detection, which comprises a machine base; a guide rail mechanism is arranged on the top of the machine base, fixed machine bodies and movable machine bodies are arranged on the two sides of the machine base, the fixed machine bodies are installed at the ends of the guide rail mechanism, and the movable machine bodies are in sliding connection with the guide rail mechanism; drive roller mechanisms are arranged on the inner side walls of the fixed machine bodies and the movable machine bodies, respectively, supporting roller mechanisms are arranged at the two ends of the machine base, respectively, high-precision laser range finders A and high-precision laser range finders B are arranged on the fixed machine bodies and the movable machine bodies. The application can replace manual high-altitude operation to reduce safety risks, synchronously measure the wear and tear of the I-beam web and the lower flange, collect weld images, improve the efficiency and accuracy of wear and tear and position through the roller type coding meter, adapt to I-beams of multiple specifications through the adjustable structure, and provide supervision basis to curb illegal replacement.

Description

Technical Field

[0001] This invention relates to the field of I-beam testing technology, and more particularly to a failure detection device for I-beams in single-girder crane machinery. Background Technology

[0002] Single-beam cranes are widely used in enterprise production due to their ease of operation and low cost, accounting for about 20% of the total use of cranes. The main beam I-beam serves as the running track for the electric hoist. With long-term use, it is prone to failure problems such as wear, corrosion, weld cracks, and main beam deflection. Among them, the wear of the web (web thickness) and the lower flange (wheel tread) is particularly prominent. They may reach the scrap condition after 2-3 years of use.

[0003] Current inspection methods for I-beams used in lifting machinery have significant shortcomings: traditional inspection relies on manual measurement using lifting platforms or scaffolding, but lifting machinery is typically 6-40 meters high, making high-altitude operations risky, inefficient, and difficult to pinpoint wear locations with poor accuracy. Furthermore, according to the "TSG51-2023 Safety Technical Regulations for Lifting Machinery," replacing worn I-beams is considered a major repair and requires a commencement notification under the "Special Equipment Safety Law of the People's Republic of China." However, unauthorized replacements are common in practice, posing serious safety hazards and regulatory loopholes.

[0004] Existing related detection technologies also cannot meet the needs: For example, Chinese patent application publication number 118004230A discloses a track center detection instrument. Although the instrument can automatically move along the track, mark the center line, and avoid obstacles, its core focus is on the detection of the track center line, and it does not involve the measurement of H-beam wear and the identification of weld defects, so it cannot be adapted to the failure detection scenario of H-beams in lifting machinery. Another example is Chinese patent application publication number CN120445119A, which discloses an H-beam detection device and method based on UAV. Although the detection device can realize the detection of the size and deflection of H-beams at high altitudes, it relies on UAV transportation, making it difficult to realize the continuous movement detection of H-beams in lifting machinery. In addition, it does not design a special measurement structure for key wear parts such as the web and lower flange, and it also lacks the function of accurately recording the wear position.

[0005] It is evident that the industry urgently needs a high-efficiency inspection device that can replace manual high-altitude operations, simultaneously detect the wear of the web and lower flange of I-beams, record the wear location, and be compatible with single-beam crane scenarios, in order to solve the technical defects of existing technologies, such as low inspection efficiency, high safety risks, and difficulties in supervision. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies, such as low inspection efficiency, high safety risks, and difficulties in supervision, and to provide a failure detection device for I-beams in single-girder crane machinery.

[0007] This invention is achieved through the following technical solution: a failure detection device for I-beams in a single-girder crane, comprising a base; a guide rail mechanism is provided on the top of the base, and a fixed body and a movable body are respectively provided on both sides of the base at both ends of the guide rail mechanism; the fixed body is installed at the end of the guide rail mechanism, and the movable body is slidably connected to the guide rail mechanism; drive roller mechanisms are respectively provided on the inner sidewalls of the fixed body and the movable body, and support roller mechanisms are respectively provided at both ends of the base below the drive roller mechanisms; the operation of the drive roller mechanism... The working part of the supporting roller mechanism can contact the top surface of the lower flange of the I-beam, and the working part of the supporting roller mechanism can contact the bottom surface of the lower flange. The driving roller mechanism and the supporting roller mechanism can form a clamping and positioning of the lower flange. The driving roller mechanism can drive the base to move along the length direction of the I-beam. Both the fixed body and the moving body are equipped with a high-precision laser rangefinder A and a high-precision laser rangefinder B. The high-precision laser rangefinder A can measure the thickness of the web plate corresponding to the side of the web plate of the I-beam, and the high-precision laser rangefinder B can measure the thickness of the lower flange corresponding to the top surface of the lower flange.

[0008] This device can directly replace the traditional method of manual high-altitude operations using lifting platforms / scaffolding. By using "clamping positioning + automatic walking", it eliminates the risk of the device falling from heights and reduces the safety risks for inspection personnel. At the same time, it simultaneously measures the web and lower flange of the I-beam, which are most prone to wear, avoiding the inefficiency of manual measurement point by point and greatly improving the inspection efficiency. Furthermore, the high precision of laser ranging solves the problem of poor accuracy in traditional visual measurement, providing reliable data support for subsequent wear judgment and supervision.

[0009] A further improvement of the present invention is that the guide rail mechanism includes two linear modules, which are symmetrically arranged at both ends of the base, and the movable body is mounted on the slider of the linear modules.

[0010] A further improvement of the present invention is that the extension direction of the linear module is perpendicular to the travel direction of the base along the I-beam.

[0011] A further improvement of the present invention is that cameras are provided on both the fixed body and the moving body, and the cameras are used for image acquisition of the I-beam.

[0012] A further improvement of the present invention is that the two high-precision laser rangefinders A, the two high-precision laser rangefinders B, and the two cameras are all arranged symmetrically.

[0013] A further improvement of the present invention is that the high-precision laser rangefinder A, the high-precision laser rangefinder B, and the camera on the fixed body and the moving body are arranged sequentially at intervals along the length of the I-beam.

[0014] A further improvement of the present invention is that the high-precision laser rangefinder A and the camera are both mounted on the top of the fixed body and the mobile body via a linkage module, and the high-precision laser rangefinder B is mounted on the top of the inner wall of the fixed body and the mobile body via a telescopic plate.

[0015] A further improvement of the present invention is that the two driving roller mechanisms and the two supporting roller mechanisms are arranged symmetrically.

[0016] A further improvement of the present invention is that the drive roller mechanism includes two drive rollers, which are respectively installed at both ends of the fixed body and the movable body.

[0017] A further improvement of the present invention is that the supporting roller mechanism is a roller-type encoder.

[0018] As can be seen from the above technical solutions, the beneficial effects of the present invention are: 1. This device, through the clamping and positioning design of the drive roller mechanism and the support roller mechanism, combined with the automatic walking function, completely replaces the manual inspection method of riding a lifting platform or erecting scaffolding. It not only eliminates the dual safety hazards of device falling from height and personnel falling, but also avoids the cumbersome process of frequently moving the lifting equipment, fundamentally reducing the safety risks for inspection personnel and ensuring the safety of high-altitude operations.

[0019] 2. This device can simultaneously measure the wear of the web and lower flange and acquire weld images without switching between different inspection items in stages. The symmetrical arrangement of the high-precision laser rangefinder can reduce unilateral measurement errors, and the roller encoder can accurately correlate wear data with the position of the I-beam. This solves the problems of low efficiency and lack of traceability of data in traditional manual point-by-point measurement, greatly improving inspection efficiency and providing reliable data support for the determination of wear degree, avoiding misjudgments and omissions due to insufficient accuracy.

[0020] 3. The device uses visual images captured by a camera and location data recorded by a encoder to serve as objective evidence for the inspection and replacement of I-beams, effectively curbing unauthorized replacement of I-beams and improving regulatory procedures. The adjustable structure, including the guide rail mechanism and connecting rod module, can adapt to I-beams of different widths and different wear marks, eliminating the need for dedicated inspection devices for different specifications of equipment, reducing enterprise inspection costs, and significantly enhancing the applicability and practical value of the device. Attached Figure Description

[0021] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a structural schematic diagram of a specific embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the drive roller mechanism and the support roller mechanism in a specific embodiment of the present invention.

[0024] Figure 3 This is a demonstration diagram of the detection operation in a specific embodiment of the present invention.

[0025] In the diagram: 1. Base; 2. Guide rail mechanism; 201. Linear module; 3. Fixed body; 4. Moving body; 5. Drive roller mechanism; 501. Drive roller; 6. Supporting roller mechanism; 7. High-precision laser rangefinder A; 8. High-precision laser rangefinder B; 9. Camera; 10. Linkage module; 11. Telescopic plate; 12. I-beam. Detailed Implementation

[0026] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0027] Now refer to Figure 1-3 The following is a description of a specific embodiment: The single-beam crane I-beam failure detection device of the present invention includes a base 1; a guide rail mechanism 2 is provided on the top of the base 1; a fixed body 3 and a movable body 4 are respectively provided on both sides of the base 1 at both ends of the guide rail mechanism 2; the fixed body 3 is installed at the end of the guide rail mechanism 2; the movable body 4 is slidably connected to the guide rail mechanism 2; the guide rail mechanism 2 can drive the movable body 4 to move along the width direction of the I-beam 12; a drive roller mechanism 5 is respectively provided on the inner sidewall of the fixed body 3 and the movable body 4; and a supporting roller is respectively provided at both ends of the base 1 below the drive roller mechanism 5. The drive roller mechanism 5 has a working part that can contact the top surface of the lower flange of the I-beam 12, and the supporting roller mechanism 6 has a working part that can contact the bottom surface of the lower flange. The drive roller mechanism 5 and the supporting roller mechanism 6 can form a clamping and positioning mechanism for the lower flange. The drive roller mechanism 5 can drive the base 1 to move along the length of the I-beam 12. Both the fixed body 3 and the moving body 4 are equipped with a high-precision laser rangefinder A7 and a high-precision laser rangefinder B8. The high-precision laser rangefinder A7 can measure the thickness of the web plate corresponding to the side of the web plate of the I-beam 12, and the high-precision laser rangefinder B8 can measure the thickness of the lower flange corresponding to the top surface of the lower flange.

[0028] In use, the guide rail mechanism 2 on the top of the base 1 first drives the movable body 4 to slide along the width direction of the I-beam 12, adjusting the distance between the fixed body 3 and the movable body 4 to match the width of the I-beam 12 to be tested. Then, the drive roller mechanism 5 on the inner sidewall of the fixed body 3 and the movable body 4 cooperates with the support roller mechanism 6 at the corresponding positions at both ends of the base 1 to contact the top and bottom surfaces of the lower flange of the I-beam 12 and form a clamping position to prevent the device from falling off the high-altitude I-beam. The drive roller mechanism 5 is activated, and it drives the entire base 1 to move along the length direction of the I-beam 12 through the friction with the top surface of the lower flange. At the same time, the high-precision laser rangefinder A7 on the fixed body 3 and the movable body 4 is aligned with the side of the web of the I-beam 12, and the high-precision laser rangefinder B8 is aligned with the top surface of the lower flange, simultaneously measuring the real-time thickness of the web and the lower flange—that is, the thickness after wear.

[0029] This device can directly replace the traditional method of manual high-altitude operations using lifting platforms / scaffolding. By using "clamping positioning + automatic walking", it eliminates the risk of the device falling from height and reduces the safety risks for inspection personnel. At the same time, it simultaneously measures the web and lower flange of the I-beam 12, which are most prone to wear, avoiding the inefficiency of manual measurement point by point and greatly improving the inspection efficiency. Moreover, the high precision of laser ranging solves the problem of poor accuracy of traditional visual measurement, providing reliable data support for subsequent wear judgment and supervision.

[0030] Specifically, refer to Figure 2 The guide rail mechanism 2 includes two linear modules 201, which are symmetrically arranged at both ends of the base 1. The movable body 4 is mounted on the slider of the linear module 201.

[0031] The guide rail mechanism 2 adopts two linear modules 201 symmetrically arranged at both ends of the base 1. The moving body 4 is fixed on the slider of the linear module 201. When it is necessary to adapt to I-beams 12 of different widths, the linear module 201 drives the slider to move along the module track, thereby driving the moving body 4 to move closer to or away from the fixed body 3, so as to adapt to I-beams 12 of different widths.

[0032] This device ensures uniform force and smooth trajectory when the moving body 4 slides through symmetrically arranged linear modules 201, avoiding body offset caused by unilateral adjustment. Compared with manual adjustment of body spacing, the automatic adjustment of linear modules greatly shortens the adaptation time and can accurately adapt to I-beams of single main beam cranes of different specifications, improving the versatility of the device.

[0033] Specifically, the extension direction of the linear module 201 is perpendicular to the travel direction of the base 1 along the I-beam 12.

[0034] The extension direction of the linear module 201 is perpendicular to the walking direction of the base 1 along the I-beam 12. That is, the linear module 201 only drives the moving body 4 in the direction "perpendicular to the length of the I-beam", that is, along the width direction of the I-beam, to ensure that the adjustment trajectory of the moving body 4 is always consistent with the width direction of the I-beam 12 and there will be no deviation along the walking direction.

[0035] This device, by limiting the direction as described above, can avoid trajectory deviation during the adjustment of the moving fuselage 4, ensuring that the fixed fuselage 3 and the moving fuselage 4 are always symmetrically distributed on both sides of the I-beam 12. This ensures that the subsequent high-precision laser rangefinders A and B can accurately align with the web and lower wing flange measurement positions, avoiding measurement errors caused by fuselage offset and further improving detection accuracy.

[0036] Specifically, refer to Figure 1 and Figure 2 Both the fixed body 3 and the mobile body 4 are equipped with cameras 9, which are used for image acquisition of the I-beam 12.

[0037] Cameras 9 are added to the fixed body 3 and the movable body 4. When the drive roller mechanism 5 drives the base 1 to move along the I-beam 12, the camera 9 simultaneously captures images of the surface of the I-beam 12, especially the weld area, and records the appearance of the weld in real time.

[0038] This device adds a "visual inspection of weld defects" function to the "wear measurement" function, eliminating the need for inspection personnel to visually inspect weld cracks, corrosion and other defects from high altitudes, thus completely eliminating the safety risks of high-altitude visual operations; at the same time, the image acquisition can retain inspection records, solving the problem of traditional manual inspection having no objective image evidence, and providing visual support for subsequent supervision and traceability.

[0039] Specifically, refer to Figure 1 and Figure 2 The two high-precision laser rangefinders A7, the two high-precision laser rangefinders B8, and the two cameras 9 are all arranged symmetrically.

[0040] Two high-precision laser rangefinders A7, two high-precision laser rangefinders B8, and two cameras 9 are symmetrically arranged on the fixed fuselage 3 and the moving fuselage 4 with the longitudinal centerline of the I-beam 12 as the axis of symmetry, respectively. During inspection, the symmetrical rangefinders simultaneously measure the thickness of the web / lower flange from both sides of the I-beam 12, and the symmetrical cameras simultaneously acquire weld images from both sides.

[0041] This device uses a symmetrical arrangement to allow the rangefinder to acquire data from both sides of the same measurement section. By comparing the data, the random errors of unilateral measurement are eliminated, further improving the reliability of wear detection. At the same time, the cameras on both sides can cover the weld area on both sides of the I-beam 12, avoiding blind spots in the field of view of unilateral shooting and ensuring that no weld defects are missed.

[0042] Specifically, refer to Figure 1 and Figure 2 The high-precision laser rangefinder A7 and the camera 9 are both mounted on the top of the fixed body 3 and the movable body 4 via the connecting rod module 10. The high-precision laser rangefinder B8 is mounted on the top of the inner wall of the fixed body 3 and the movable body 4 via the telescopic plate 11.

[0043] The high-precision laser rangefinder A7 and camera 9 are mounted on the top of the fixed fuselage 3 and the movable fuselage 4 via the linkage module 10. By adjusting the length and angle of the linkage module 10, the rangefinder A7 can be aligned with the wear mark area of ​​the web plate of the I-beam 12, and the camera 9 can be aligned with the critical area of ​​the weld. The high-precision laser rangefinder B8 is mounted on the top of the inner wall of the fuselage via the telescopic plate 11. The lateral position of the rangefinder B8 can be adjusted by extending and retracting the telescopic plate 11, so that it is aligned with the wear area of ​​the wheel tread on the lower flange.

[0044] This device, through the adjustable design of the connecting rod module 10 and the telescopic plate 11, enables the rangefinder and camera to accurately adapt to the wear position of the I-beams of different single-beam cranes. Because the running trajectory of the electric hoist is different, the location of the wear marks may vary, eliminating the need to replace the special detection device and greatly improving the adaptability of the device. At the same time, it can focus on the wear area for targeted measurement, avoiding data interference from non-wear areas and improving the effectiveness of the detection data.

[0045] Specifically, refer to Figure 2 The two driving roller mechanisms 5 and the two supporting roller mechanisms 6 are arranged symmetrically.

[0046] Two drive roller mechanisms 5 are symmetrically arranged on the inner sidewalls of the fixed body 3 and the movable body 4, respectively. Two support roller mechanisms 6 are symmetrically arranged at both ends of the base 1 below the corresponding drive roller mechanisms 5. During testing, the symmetrical drive roller mechanisms 5 apply uniform pressure from both sides of the top surface of the lower flange of the I-beam 12, and the symmetrical support roller mechanisms 6 provide uniform support from both sides of the bottom surface of the lower flange, together forming a stable clamping structure.

[0047] This device, through a symmetrically arranged roller mechanism, ensures uniform force distribution on the lower flange of the I-beam 12, preventing tilting or displacement of the base 1 caused by unilateral force. Especially when traveling at heights, it effectively prevents the device from tipping over and falling off, further enhancing the safety of high-altitude inspections. At the same time, the uniform clamping force ensures stable friction between the drive roller mechanism 5 and the top surface of the lower flange, preventing slippage and resulting travel interruptions, and ensuring the continuity of the inspection process.

[0048] Specifically, refer to Figure 2 The drive roller mechanism 5 includes two drive rollers 501, which are respectively installed at both ends of the fixed body 3 and the movable body 4.

[0049] Each drive roller mechanism 5 includes two drive rollers 501, which are respectively installed at both ends of the fixed fuselage 3 or the movable fuselage 4 along the length of the I-beam. When started, the drive rollers 501 at both ends of the same fuselage rotate synchronously and, through the friction with the top surface of the lower flange of the I-beam 12, jointly drive the base 1 to move along the length of the I-beam.

[0050] This device uses a dual-drive roller 501 design at both ends of the same body to distribute the driving force, avoid slippage caused by insufficient friction of a single drive roller, and ensure stable travel speed of the base 1. At the same time, the increased number of support points of the dual rollers can further improve the stability of the base 1 when traveling at high altitudes, reduce detection interruptions caused by failure of a single roller, and improve the reliability of the device.

[0051] Specifically, the supporting roller mechanism 6 is a roller-type encoder.

[0052] The roller support mechanism 6 adopts a roller-type encoder. When the base 1 moves along the length of the I-beam 12, the bottom surface of the lower flange of the I-beam 12 drives the roller of the roller-type encoder to rotate. The encoder calculates the real-time travel distance of the base 1 by the number of rotations of the roller, and then associates the wear data measured by the high-precision laser rangefinders A7 and B8 with the corresponding I-beam position.

[0053] This device can accurately record the wear location using a roller-type encoder, solving the problems of low efficiency and large error in traditional manual marking of wear locations. It achieves a one-to-one correspondence between "wear amount and location", which facilitates the accurate location of I-beam sections that need repair or replacement. At the same time, this location data can serve as a basis for supervision, effectively tracing the wear of I-beams, curbing unauthorized replacement of I-beams, and improving the supervision process.

[0054] In one embodiment, reference Figure 1 and Figure 2 The high-precision laser rangefinder A7, high-precision laser rangefinder B8, and camera 9 on the fixed body 3 and the mobile body 4 are arranged sequentially at intervals along the length of the I-beam 12.

[0055] The high-precision laser rangefinder A7, high-precision laser rangefinder B8, and camera 9 on the fixed fuselage 3 and the moving fuselage 4 are arranged sequentially at intervals along the length of the I-beam 12—that is, the direction of travel of the base 1. When the base 1 moves, the device first measures the web thickness through the rangefinder A, then measures the lower flange thickness through the rangefinder B, and finally collects the weld image through the camera. There is no spatial interference between the functional modules.

[0056] This device avoids obstruction caused by spatial overlap between the rangefinder and the camera due to the spacing along the walking direction. This prevents the rangefinder from blocking the camera's field of view or the camera from interfering with the laser beam path. It ensures that the wear measurement and image acquisition functions operate independently and smoothly, eliminating the need to frequently start and stop the device to switch detection items and improving overall detection efficiency.

[0057] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A failure detection device for I-beams in a single-girder crane, comprising a base (1), characterized in that, The top of the base (1) is provided with a guide rail mechanism (2). The base (1) is provided with a fixed body (3) and a movable body (4) located at both ends of the guide rail mechanism (2). The fixed body (3) is installed at the end of the guide rail mechanism (2), and the movable body (4) is slidably connected to the guide rail mechanism (2). The inner sidewalls of the fixed body (3) and the movable body (4) are respectively provided with drive roller mechanisms (5). The two ends of the base (1) are respectively provided with supporting roller mechanisms (6) located below the drive roller mechanisms (5). The working part of the drive roller mechanism (5) can contact the top surface of the lower flange of the I-beam (12). The working part of the supporting roller mechanism (6) can contact the bottom surface of the lower flange. The driving roller mechanism (5) and the supporting roller mechanism (6) can form a clamping and positioning of the lower flange. The driving roller mechanism (5) can drive the base (1) to move along the length direction of the I-beam (12). The fixed fuselage (3) and the moving fuselage (4) are equipped with a high-precision laser rangefinder A (7) and a high-precision laser rangefinder B (8). The high-precision laser rangefinder A (7) can measure the thickness of the web plate corresponding to the side of the web plate of the I-beam (12). The high-precision laser rangefinder B (8) can measure the thickness of the lower flange corresponding to the top surface of the lower flange.

2. The single-girder crane I-beam failure detection device according to claim 1, characterized in that, The guide rail mechanism (2) includes two linear modules (201), which are symmetrically arranged at both ends of the base (1). The moving body (4) is mounted on the slider of the linear module (201).

3. The single-girder crane I-beam failure detection device according to claim 2, characterized in that, The extension direction of the linear module (201) is perpendicular to the walking direction of the base (1) along the I-beam (12).

4. The failure detection device for I-beams in single-girder cranes according to claim 1, characterized in that, Both the fixed body (3) and the mobile body (4) are equipped with cameras (9), which are used for image acquisition of the I-beam (12).

5. The single-girder crane I-beam failure detection device according to claim 4, characterized in that, The two high-precision laser rangefinders A (7), the two high-precision laser rangefinders B (8), and the two cameras (9) are all arranged symmetrically.

6. The failure detection device for I-beams in single-girder cranes according to claim 5, characterized in that, The high-precision laser rangefinder A (7), high-precision laser rangefinder B (8), and camera (9) on the fixed body (3) and the mobile body (4) are arranged sequentially at intervals along the length of the I-beam (12).

7. The single-girder crane I-beam failure detection device according to claim 6, characterized in that, The high-precision laser rangefinder A (7) and the camera (9) are both installed on the top of the fixed body (3) and the mobile body (4) via the linkage module (10), and the high-precision laser rangefinder B (8) is installed on the top of the inner wall of the fixed body (3) and the mobile body (4) via the telescopic plate (11).

8. The failure detection device for I-beams in single-girder cranes according to claim 1, characterized in that, The two drive roller mechanisms (5) and the two support roller mechanisms (6) are arranged symmetrically.

9. A failure detection device for I-beams in single-girder cranes according to claim 8, characterized in that, The drive roller mechanism (5) includes two drive rollers (501), which are respectively installed at both ends of the fixed body (3) and the movable body (4).

10. A failure detection device for I-beams in single-girder cranes according to claim 9, characterized in that, The supporting roller mechanism (6) is a roller encoder.

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