Detection method and detection device for thermit welding seam of high-speed rail turnout

Abstract

The invention discloses a high-speed rail turnout thermit welding seam detection method and a detection device, and relates to the technical field of rail performance testing, the detection device is connected with an ultrasonic detector, and the detection device is placed in the center of a rail bottom surface for scanning from bottom to top. A scanning knob is operated to enable a probe in the device to rotate clockwise or anticlockwise to realize a defect scanning function, when defects are found, the detection device is translated rightwards, and the defect equivalent is calculated and confirmed according to the displacement and amplitude change of outgoing waves; the sound path distance of the defect is calculated through the wave outlet position of the ultrasonic detector, the rotation angle of a probe is determined through a knob center dial and a pointer of an adjusting rod of the detection device, and the transverse translation amount is determined through a translation limiting sliding block; the sound path distance, the horizontal position and the equivalent of the defect are calculated according to the probe rotation angle, the probe refraction angle and the transverse translation amount; according to the invention, 360-degree detection angle adjustment of the probe can be realized, so that the position and angle adjustment of the probe are flexible and accurate, and the device is particularly suitable for accurate and comprehensive performance detection of a triangular area of a steel rail thermit welding seam.

Description

Technical Field

[0001] The present invention relates to the technical field of rail performance testing, and in particular to a method and a device for detecting thermite welds of high-speed railway turnouts. Background Art

[0002] Amidst the rapid growth of the railway transportation industry, rails, as a key component of railway tracks, are crucial for train safety. However, the welds formed during the thermite welding process—where aluminum and steel are heated to high temperatures—particularly the fusion triangle, due to their complex geometry and unique stress state, have become a weak link in the track structure. While existing rail weld inspection equipment and technologies are effective for routine inspections, they present numerous challenges and deficiencies in comprehensive scanning and high-precision weld inspection.

[0003] 1) The scanning range is limited and there are blind spots in the detection

[0004] Some rail weld inspection devices currently on the market use multi-axis moving components and rotating mechanisms to drive ultrasonic detection heads for scanning. However, their rotational scanning range is extremely limited, making it impossible to achieve 360° coverage of the weld. Taking the thermite weld of a turnout as an example, theoretically, both the inner and outer sides must be inspected to meet the comprehensive inspection requirements. However, due to space limitations, only one side can be scanned in practice. This undoubtedly makes a large area a blind spot for inspection, making it impossible to detect potential weld defects in a timely manner, posing a hidden danger to railway operation safety. Moreover, these devices are also limited to fixed-site inspections, and can only inspect specific areas, making it difficult to conduct a systematic and comprehensive inspection of the entire weld area, further expanding the scope of the inspection blind spot.

[0005] 2) The scanning angle is narrow and cannot adapt to complex structures

[0006] Some inspection devices only offer a 30° scan angle on each side, a scan range that's insufficient for the complex and varied weld structures. Welds have complex and diverse geometries, and defects in different locations can occur at various angles. This limited scanning angle simply can't meet the requirements for comprehensive inspection of these complex weld geometries. This limitation is particularly pronounced when dealing with welds with complex three-dimensional structures, making it difficult to accurately capture defect information at every location, leading to significant errors in inspection results.

[0007] 3) The detection method relies on manual labor, and the accuracy is difficult to guarantee

[0008] Some inspection devices use a manual lever-based scanning method, which is highly dependent on the operator's experience and skill level. In practice, due to the limitations of manual operation, it is difficult to ensure that the force, speed, and angle of each scan are exactly the same. This leads to inaccurate scanning processes and significantly reduces the repeatability and accuracy of test results. Furthermore, manual operation is inefficient. When faced with large-scale rail weld inspection tasks, it not only consumes a significant amount of time and labor costs, but can also lead to missed detections and false detections due to human factors, seriously affecting inspection efficiency and reliability.

[0009] 4) Single detection function and lack of comprehensiveness

[0010] While some rail weld identification systems can automatically identify and locate welds using acoustic sensors and coupling media, and optimize inspection data through data correction units, their functionality is limited. They primarily focus on weld location identification and data correction, but lack the ability to comprehensively scan complex weld geometries. Their detection methods are limited to a single-directional acoustic wave propagation path, making them incapable of adapting to the complex three-dimensional structure of welds. In actual inspections, weld defects can exist in various directions and locations, making it difficult to fully and accurately detect these defects using a single-directional acoustic wave propagation path. This reduces overall inspection accuracy and reliability, and fails to provide a strong guarantee for railway transportation safety. Summary of the Invention

[0011] The purpose of the present invention is to provide a high-speed railway turnout thermite weld detection method and detection device to solve the problems existing in the above-mentioned prior art. The method can adjust the probe position and angle 360° to achieve more comprehensive performance testing of the weld triangle area and improve detection accuracy and reliability.

[0012] To achieve the above object, the present invention provides the following solutions:

[0013] The present invention provides a method for detecting thermite welds of high-speed railway turnouts, comprising the following steps:

[0014] Step 1: Add ultrasonic coupling liquid to the probe surface of the detection device. Adjust the limit slider on the detection device according to the rail type to be measured using the scale on the surface of the connecting rod. Press the limit slider against the outer edge of the bottom surface of the rail so that the detection device is magnetically adsorbed and installed at the center of the bottom surface of the rail. During installation, connect the detection device to the ultrasonic detector through the probe line interface on the handle of the detection device.

[0015] Step 2: Operate the scanning knob to rotate the probe in the device clockwise or counterclockwise to scan for defects. If a defect is found, move the detection device to the right.

[0016] Step 3: Calculate and confirm the defect equivalent based on the displacement and amplitude of the outgoing wave; calculate the sound path of the defect through the outgoing wave position of the ultrasonic detector, determine the probe rotation angle through the knob center dial and pointer of the adjustment rod of the detection device, and determine the lateral translation through the translation limit slider;

[0017] Step 4: Calculate the sound path, horizontal position and equivalent of the defect based on the probe rotation angle, probe refraction angle and lateral translation.

[0018] Preferably, the calculation step of determining the defect position in step 4 specifically includes:

[0019] (1) Defect depth H

[0020] Formula: H = S·cosβ

[0021] Where S is the sound path of the damage wave, and β is the refraction angle of the probe. This formula is based on the principle of trigonometric functions. The projection of the sound path S in the vertical direction is the defect depth.

[0022] (2) Defect transverse and longitudinal distances X and Y

[0023] Formula: X = S sinβ sinα + Δx

[0024] Y=S·sinβ·cosα

[0025] Where α is the probe rotation angle, Δx is the lateral translation; Y is the longitudinal projection distance of the sound path S in the horizontal direction combined with the probe rotation angle α; X is the lateral projection distance of the sound path S in the horizontal direction combined with the probe rotation angle α, plus the lateral translation Δx;

[0026] (3) Defect width W

[0027] Find the strongest echo point and record the horizontal coordinate X0; move the probe laterally along the rail bottom and observe the echo amplitude drop to -6dB, and record the horizontal coordinates X1 and X2 on both sides;

[0028] Formula: W = |X2-X1|, the defect width is obtained by calculating the difference between the half-wave point positions on both sides;

[0029] (4) Defect length L

[0030] Fix the transverse position, i.e., Δx = 0, rotate the probe, and record the change in echo amplitude; when the echo amplitude drops to -6 dB, record the rotation angles α1 and α2;

[0031] Formula: L = S·sinβ·|sinα2-sinα1|. The defect length is calculated based on the sound path S, the probe refraction angle β, and the rotation angle corresponding to the two half-wave points.

[0032] Preferably, the detection device includes a base, a handle, a probe housing, an adjusting rod, a connecting rod, a pulley transmission mechanism, a rotating probe and a limit slider, the handle is arranged at the bottom of the base for grasping the movement of the entire device, the probe housing is connected to the top of the base through the connecting rod, the adjusting rod is rotatably connected to the base, the rotating probe is rotatably connected to the probe housing, one end of the adjusting rod is connected to the rotating probe through the pulley transmission mechanism, and the adjusting rod is rotated to drive the rotating probe to rotate through the pulley transmission mechanism; the limit slider is sleeved on the outside of the connecting rod and is located between the base and the probe housing, the limit slider is slidably connected to the connecting rod and can be locked by a locking screw, the locking screw is threadedly connected to the screw hole set on the limit slider and the inner end passes through the screw hole and is opposite to the connecting rod.

[0033] Preferably, the handle is provided with a handle, the handle is a non-slip rubber handle, and the surface of the handle is provided with non-slip textures.

[0034] Preferably, a through hole is provided inside the base for the adjusting rod to pass through, one end of the adjusting rod is a knob, and the other end of the adjusting rod passes through the through hole to be connected to the pulley transmission mechanism, and the knob can drive the adjusting rod to rotate 360°; an angle scale and a pointer are provided on the knob, and the measuring angle of the rotating probe can be determined by rotating the knob to the corresponding scale.

[0035] Preferably, the pulley transmission mechanism includes pulley 1, pulley 2 and a toothed track, pulley 1 is connected to the adjusting rod, pulley 1 is connected to pulley 2 through the toothed track, and pulley 2 is connected to the rotating probe through a wheel shaft.

[0036] Preferably, the probe housing is a circular structure with a through hole inside, and the rotating probe is rotatably connected in the through hole.

[0037] Preferably, the probe is a 70° probe, which is arranged at the front end of the rotating base, and the rotating base is rotatably connected to the inner through hole of the probe housing. The pulley 2 is arranged on the back of the rotating base and is connected to the rotating base through a gear shaft, and a circle of magnets is embedded in the front of the probe housing along the circumferential direction.

[0038] Preferably, an annular cover plate is further provided on the front side of the probe housing, and a circle of magnets is embedded in the cover plate along the circumferential direction.

[0039] Preferably, the connecting rod is provided with a scale marking the position of the limiting slider on the connecting rod.

[0040] Compared with the prior art, the present invention has achieved the following technical effects:

[0041] The high-speed railway turnout thermite weld detection method and detection device of the present invention realize 360° detection angle adjustment of the rotating probe by rotating the adjustment rod in conjunction with the transmission mechanism, making the adjustment of the probe position and angle flexible and accurate. Only one-side detection can achieve blind spot scanning, which is particularly suitable for accurate and comprehensive performance testing of the triangular area of the rail weld.

[0042] Furthermore, the knob of the adjustment rod is provided with a pointer synchronized with the probe direction, which can follow the rotation of the knob and accurately determine the measuring angle of the rotating probe according to the surface scale, meeting the needs of precise detection of welds and improving the accuracy and reliability of detection.

[0043] Furthermore, mobile detection can be achieved by lateral translation of the translation sliding bearing on the limit slider. At the same time, combined with relevant formulas, the level, depth and equivalent can be quickly calculated, further improving the convenience and accuracy of detection.

[0044] Furthermore, the measurement reference line designed on the base can assist operators in quickly and accurately determining the location of defects, greatly improving detection efficiency and reducing repeated detection work caused by inaccurate positioning.

[0045] Furthermore, the magnet is made of high magnetic material, which enhances the stability of the device during operation and improves the safety and reliability of operation.

[0046] Furthermore, the crawler transmission mechanism enables precise and smooth adjustment of the probe angle, meeting the needs of different detection angles.

[0047] Furthermore, the high-precision scale lines on the connecting rod determine the precise position of the probe at the bottom of the rail, thereby improving the accuracy of defect location measurement and further enhancing the accuracy and reliability of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0049] Figure 1 This is a schematic diagram of the three-dimensional structure of the high-speed railway turnout thermite weld detection device of the present invention;

[0050] In the figure: 1. Base; 2. Connecting rod; 3. Limit slider; 4. Rotating base; 5. Probe; 6. Probe housing; 7. Cover plate; 8. Pulley 1; 9. Toothed track; 10. Pulley 2; 11. Adjustment lever; 12. Pointer; 13. Knob; 14. Handle; 15. Measuring reference line. DETAILED DESCRIPTION

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0052] The purpose of the present invention is to provide a high-speed railway turnout thermite weld detection method and detection device to solve the problems existing in the prior art.

[0053] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] The high-speed railway turnout thermite weld detection method in this embodiment is as follows: Figure 1 As shown, the following steps are included:

[0055] Step 1: Add ultrasonic coupling liquid to the surface of the probe 5 of the detection device. Adjust the limit slider 3 on the detection device according to the rail type to be measured through the scale on the surface of the connecting rod 2. Press the limit slider 3 against the outer edge of the bottom surface of the rail so that the detection device is magnetically adsorbed and installed at the center of the bottom surface of the rail. During installation, connect the detection device to the ultrasonic detector through the probe 5 wire interface on the handle 14 of the detection device.

[0056] Step 2: Operate the scanning knob 13 to rotate the probe 5 in the device clockwise or counterclockwise to realize the defect scanning function. When a defect is found, move the detection device to the right.

[0057] Step 3: Calculate and confirm the defect equivalent based on the displacement and amplitude of the outgoing wave; calculate the sound path of the defect through the outgoing wave position of the ultrasonic detector, determine the rotation angle of the probe 5 through the center dial and pointer of the knob 13 of the adjustment rod 11 of the detection device, and determine the lateral translation amount by translating the limit slider 3;

[0058] Step 4: Calculate the sound path, horizontal position and equivalent of the defect based on the rotation angle of probe 5, the refraction angle of probe 5 and the lateral translation.

[0059] The calculation steps for determining the defect location in step 4 include:

[0060] (1) Defect depth H

[0061] Formula: H = S·cosβ

[0062] Where S is the sound path of the damage wave, and β is the refraction angle of the probe. This formula is based on the principle of trigonometric functions. The projection of the sound path S in the vertical direction is the defect depth.

[0063] (2) Defect transverse and longitudinal distances X and Y

[0064] Formula: X = S sinβ sinα + Δx

[0065] Y=S·sinβ·cosα

[0066] Where α is the probe rotation angle, Δx is the lateral translation; Y is the longitudinal projection distance of the sound path S in the horizontal direction combined with the probe rotation angle α; X is the lateral projection distance of the sound path S in the horizontal direction combined with the probe rotation angle α, plus the lateral translation Δx;

[0067] (3) Defect width W

[0068] Find the strongest echo point and record the horizontal coordinate X0; move the probe laterally along the rail bottom and observe the echo amplitude drop to -6dB, and record the horizontal coordinates X1 and X2 on both sides;

[0069] Formula: W = |X2-X1|, the defect width is obtained by calculating the difference between the half-wave point positions on both sides;

[0070] (4) Defect length L

[0071] Fix the transverse position, i.e., Δx = 0, rotate the probe, and record the change in echo amplitude; when the echo amplitude drops to -6 dB, record the rotation angles α1 and α2;

[0072] Formula: L = S·sinβ·|sinα2-sinα1|. The defect length is calculated based on the sound path S, the probe refraction angle β, and the rotation angle corresponding to the two half-wave points.

[0073] Example calculation (defective test block)

[0074] Description of test block groove distribution (with the weld as the coordinate origin)

[0075] Groove 1: Located on the right side of the weld (fourth quadrant), 17 mm from the center of the rail, 26.4 mm from the bottom of the rail, vertical cutting (10 mm long, 3 mm deep).

[0076] Groove 2: Located on the left side of the weld (second quadrant), 20 mm from the center of the rail, 24 mm from the bottom of the rail, vertical cutting (10 mm long, 3 mm deep).

[0077] Groove 3: Located in the parent material (away from the weld), 17 mm from the rail center, 26.4 mm from the rail bottom, vertical cutting (10 mm long, 3 mm deep).

[0078] Groove 4: Located in the parent material (away from the weld), 20 mm from the center of the rail, 24 mm from the bottom of the rail, vertical cutting (10 mm long, 3 mm deep).

[0079] Detection steps and data recording

[0080] 1. Device installation and initial setup

[0081] Probe settings: 70° refraction angle probe, rotation angle zero (α=0°), initial position of limit slider ΔL=0.

[0082] Couplant: Apply ultrasonic couplant evenly.

[0083] Baseline alignment: Align the scale line on the base with the center line of the rail bottom to ensure that the probe's incident point is at the center of the rail bottom.

[0084] 2. Notch 1 inspection (right side of weld, fourth quadrant)

[0085] Adjust the probe angle:

[0086] Rotate the adjustment rod to point the probe to the right (α=-25°).

[0087] The ultrasonic detector shows the highest echo and records the sound path S = 55mm.

[0088] Calculate defect location:

[0089] Distance from rail center (lateral):

[0090] N=S·sin(70°)·sin(25°)=55×0.94×0.423≈+21.9mm

[0091] (Theoretical value: +17mm, due to oblique incidence, correction is required. After adjusting α = 20°, N≈+17.2mm)

[0092] Height from rail bottom:

[0093] H=S·cos(70°)=55×0.342≈18.8mm

[0094] (Because the test block groove height is 26.4mm, it is necessary to correct the sound path S = 26.4 / cos (70°) ≈ 77mm, and match after retesting)

[0095] Defect size measurement:

[0096] Move the limit slider horizontally. When the amplitude drops to 50%, W_scan = 10mm. Calculate the groove width:

[0097] W_defect=10·sin(70°)-5≈4.4mm

[0098] For the longitudinal moving device, when the amplitude drops to 50%, L_scan = 14 mm. Calculate the groove length:

[0099] L_defect = 14-5 = 9 mm

[0100] 3. Notch 2 inspection (left side of weld, third quadrant)

[0101] Adjust the probe angle:

[0102] Rotate the adjustment lever to point the probe to the left (α=30°).

[0103] The ultrasonic detector showed the highest echo and recorded the sound path S = 58mm.

[0104] Calculate defect location:

[0105] Distance from rail center (lateral):

[0106] N=58·sin(70°)·sin(30°)≈-25.4mm

[0107] (Theoretical value: -20mm, after adjusting α=25°, N≈-20.1mm)

[0108] Height from rail bottom:

[0109] H=58·cos(70°)≈19.8mm

[0110] Defect size measurement:

[0111] Horizontal scan W_scan=11mm, calculate width:

[0112] W_defect=11·sin(70°)-5≈5.3mm

[0113] Longitudinal scan L_scan = 13 mm, calculate the length:

[0114] L_defect = 13-5 = 8 mm

[0115] 4. Inspection of groove 3 and groove 4 (base material area)

[0116] operate:

[0117] Keep the probe angle α = ±20° and move the device along the longitudinal direction of the rail to the base material area.

[0118] The echo signals of groove 3 (+17mm) and groove 4 (-20mm) are consistent with those of groove 1 / 2, with only a slightly increased sound path (because there is no weld interference in the base material).

[0119] Conclusion: The device can still accurately locate defects in the base material area without changing the scanning side.

[0120] Test conclusion

[0121] Verification of Ipsilateral Scanning Capability:

[0122] By rotating the probe angle, the left and right sides of the weld can be covered (1 / 2 of the groove).

[0123] The detection logic of the parent material area (groove 3 / 4) is the same, proving that the device is applicable to the entire rail range.

[0124] Defect size calculation:

[0125] Length error ≤ 1mm, width error ≤ 2mm.

[0126] No need to change sides: single-side operation throughout the entire process ensures inspection in narrow spaces such as high-speed railway switches.

[0127] Note: During actual testing, the angle and sound path correction coefficients need to be fine-tuned according to the rail parameters. This example only shows the standardized process.

[0128] The detection device involved in the above-mentioned high-speed railway turnout thermite weld detection method includes a base 1, a handle 14, a probe housing 6, an adjusting rod 11, a connecting rod 2, a pulley transmission mechanism, a probe 5 and a limit slider 3. The handle 14 is arranged at the bottom of the base 1 and is used to grasp the movement of the entire device. The probe housing 6 is connected to the top of the base 1 through the connecting rod 2. The adjusting rod 11 is rotatably connected to the base 1, and the probe 5 is rotatably connected to the probe housing 6. One end of the adjusting rod 11 is connected to the probe 5 through the pulley transmission mechanism. The rotating adjusting rod 11 drives the probe 5 to rotate through the pulley transmission mechanism, thereby realizing the angle adjustment of the probe 5 in step 2; the limit slider 3 is sleeved on the outside of the connecting rod 2 and is located between the base 1 and the probe housing 6. The limit slider 3 is slidably connected to the connecting rod 2 and can be locked by a locking screw. The locking screw is threadedly connected to the screw hole set on the limit slider 3 and the inner end passes through the screw hole and is opposite to the connecting rod 2.

[0129] In this embodiment, the handle 14 is provided with a grip, which is a non-slip rubber grip, and the surface of the grip is provided with non-slip textures.

[0130] In this specific embodiment, a through hole is provided inside the base 1 for the passage of the adjustment rod 11. One end of the adjustment rod 11 is a knob 13, and the other end of the adjustment rod 11 passes through the through hole and is connected to the pulley transmission mechanism. The knob 13 can drive the adjustment rod 11 to rotate 360°. The knob 13 is provided with an angle scale and a pointer 12. The measurement angle of the probe 5 can be determined by rotating the knob 13 to the corresponding scale. A measurement reference line 15 is provided on the front side wall of the base 1. The position of the measurement reference line 15 is the probe incident point. During operation, the sound range displayed by the instrument is the horizontal and vertical distances from the probe incident point to the defect location. Carving a measurement reference line on the base allows for accurate positioning when a defect occurs, and can assist operators in quickly and accurately determining the defect location.

[0131] In this embodiment, the pulley transmission mechanism includes pulley 1 8 , pulley 2 10 , and a toothed track 9 . Pulley 1 8 is connected to an adjustment rod 11 . Pulley 1 8 is connected to pulley 2 10 via the toothed track 9 . Pulley 2 10 is connected to the probe 5 via a wheel axle. The probe housing 6 is a circular ring structure with an internal through-hole, and the probe 5 is rotatably connected within the through-hole. The probe 5 is a 70° probe, located at the front end of the rotating base 4 , which is rotatably connected to the internal through-hole of the probe housing 6 . Pulley 2 10 is located at the back of the rotating base 4 and is connected to the rotating base 4 via a gear shaft. The front of the probe housing 6 is embedded with a ring of magnets along the circumference. The probe 5 is fixed to the rotating base 4 and can be adjusted 360° in position and angle via a movable device (moved by a person grasping the handle 14) and a rotating adjustment rod 11. The rotating probe 5 can freely adjust its angle and position within a 360° range to meet the inspection requirements of different weld triangles, achieving all-round rotational scanning.

[0132] In this specific embodiment, a scale marking the position of the limit slider 3 on the connecting rod 2 is provided on the connecting rod 2 .

[0133] Base 1: Base 1 is the main supporting structure of the device, which provides portability and stability, ensuring that the device does not shake or tilt during movement.

[0134] Handle 14: Fixed to the bottom of base 1, handle 14 is made of non-slip material for easy grip. Handle 14 facilitates easy handling of the device during loading and unloading. Handle 14 is hollow, allowing the probe 5 lead wire to pass through and exit the handle at the end for easy connection to the instrument. This design allows operators to easily lift, move, and place the device, improving work efficiency and convenience.

[0135] Adjustment rod 11: The design of the adjustment rod 11 enables the angle of the rotating probe 5 to be precisely adjusted to meet the requirements of different detection angles.

[0136] Pulley transmission mechanism: ensures that the belt can rotate accurately and smoothly when the adjustment rod 11 is rotated, thereby ensuring the adjustment accuracy of the probe 5 angle.

[0137] Connecting rod 2: Connecting rod 2 connects base 1 to probe housing 6, ensuring the overall stability and structural rigidity of the device. This prevents deformation or loosening during testing. High-precision scale lines are marked on it, allowing accurate positioning of probe 5 and assisting in defect location measurement. This design also ensures the overall stability and structural rigidity of the device, ensuring stability during testing.

[0138] Probe housing 6: A magnet is mounted on the cover 7 of probe housing 6 to ensure the device remains firmly attached to the rail during operation. The design of probe housing 6 takes into account the unevenness of the rail surface and ensures that the device remains stable under various operating conditions.

[0139] Rotating probe 5: Attached to probe housing 6, rotating probe 5 can be adjusted 360° in position and angle via a moving mechanism (moved by a person grasping handle 14) and rotating adjustment lever 11. Rotating probe 5 can freely adjust its angle and position within a 360° range to accommodate inspection requirements in various weld triangles, enabling full-scale rotational scanning.

[0140] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A method for detecting thermite welds of high-speed railway turnouts, characterized in that: The following steps are involved: Step 1: Add ultrasonic coupling liquid to the probe surface of the detection device. Adjust the limit slider on the detection device according to the rail type to be measured using the scale on the surface of the connecting rod. Press the limit slider against the outer edge of the bottom surface of the rail so that the detection device is magnetically adsorbed and installed at the center of the bottom surface of the rail. During installation, connect the detection device to the ultrasonic detector through the probe line interface on the handle of the detection device. Step 2: Operate the scanning knob to rotate the probe in the device clockwise or counterclockwise to scan for defects. If a defect is found, move the detection device to the right. Step 3: Calculate and confirm the defect equivalent based on the displacement and amplitude of the outgoing wave; calculate the sound path of the defect through the outgoing wave position of the ultrasonic detector, determine the probe rotation angle through the knob center dial and pointer of the adjustment rod of the detection device, and determine the lateral translation through the translation limit slider; Step 4: Calculate the sound path, horizontal position and equivalent of the defect based on the probe rotation angle, probe refraction angle and lateral translation.

2. The high-speed railway turnout thermite weld detection method according to claim 1, characterized in that: The calculation step of determining the defect position in step 4 specifically includes: (1) Defect depth H Formula: H = S·cosβ Where S is the sound path of the damage wave, and β is the refraction angle of the probe. This formula is based on the principle of trigonometric functions. The projection of the sound path S in the vertical direction is the defect depth. (2) Defect transverse and longitudinal distances X and Y Formula: X = S sinβ sinα + Δx Y=S·sinβ·cosα Where α is the probe rotation angle, Δx is the lateral translation; Y is the longitudinal projection distance of the sound path S in the horizontal direction combined with the probe rotation angle α; X is the lateral projection distance of the sound path S in the horizontal direction combined with the probe rotation angle α, plus the lateral translation Δx; (3) Defect width W Find the strongest echo point and record the horizontal coordinate X0; move the probe laterally along the rail bottom and observe the echo amplitude drop to -6dB, and record the horizontal coordinates X1 and X2 on both sides; Formula: W = |X2-X1|, the defect width is obtained by calculating the difference between the half-wave point positions on both sides; (4) Defect length L Fix the transverse position, i.e., Δx = 0, rotate the probe, and record the change in echo amplitude; when the echo amplitude drops to -6 dB, record the rotation angles α1 and α2; Formula: L = S·sinβ·|sinα2-sinα1|. The defect length is calculated based on the sound path S, the probe refraction angle β, and the rotation angle corresponding to the two half-wave points.

3. The high-speed railway turnout thermite weld detection method according to claim 1, characterized in that: The detection device includes a base, a handle, a probe housing, an adjusting rod, a connecting rod, a pulley transmission mechanism, a rotating probe and a limit slider. The handle is arranged at the bottom of the base for grasping the movement of the entire device. The probe housing is connected to the top of the base through the connecting rod. The adjusting rod is rotatably connected to the base, and the rotating probe is rotatably connected to the probe housing. One end of the adjusting rod is connected to the rotating probe through the pulley transmission mechanism, and the adjusting rod is rotated to drive the rotating probe to rotate through the pulley transmission mechanism; the limit slider is sleeved on the outside of the connecting rod and is located between the base and the probe housing. The limit slider is slidably connected to the connecting rod and can be locked by a locking screw. The locking screw is threadedly connected to the screw hole set on the limit slider and the inner end passes through the screw hole and is opposite to the connecting rod.

4. The high-speed railway turnout thermite weld detection method according to claim 3, characterized in that: The handle is provided with a handle, which is a non-slip rubber handle, and the surface of the handle is provided with non-slip lines.

5. The high-speed railway turnout thermite weld detection method according to claim 3, characterized in that: A through hole is provided inside the base for the adjusting rod to pass through, one end of the adjusting rod is a knob, and the other end of the adjusting rod passes through the through hole to be connected to the pulley transmission mechanism, and the knob can drive the adjusting rod to rotate 360°; an angle scale and a pointer are provided on the knob, and the measuring angle of the rotating probe can be determined by turning the knob to the corresponding scale.

6. The high-speed railway turnout thermite weld detection method according to claim 5, characterized in that: The pulley transmission mechanism includes pulley 1, pulley 2 and a toothed track, wherein pulley 1 is connected to the adjusting rod, pulley 1 is connected to pulley 2 through the toothed track, and pulley 2 is connected to the rotating probe through a wheel shaft.

7. The high-speed railway turnout thermite weld detection method according to claim 6, characterized in that: The probe housing is a circular ring structure with a through hole inside, and the rotary probe is rotatably connected in the through hole.

8. The high-speed railway turnout thermite weld detection method according to claim 7, characterized in that: The probe is a 70° probe, which is arranged at the front end of the rotating base. The rotating base is rotatably connected to the inner through hole of the probe housing. The second pulley is arranged on the back of the rotating base and connected to the rotating base through a gear shaft. A circle of magnets is embedded in the front of the probe housing along the circumferential direction.

9. The high-speed railway turnout thermite weld detection method according to claim 8, characterized in that: The front of the probe housing is further provided with an annular cover plate, and a circle of magnets is embedded in the cover plate along the circumferential direction.

10. The high-speed railway turnout thermite weld detection method according to claim 3, characterized in that: The connecting rod is provided with a scale marking the position of the limiting slider on the connecting rod.

Images