Electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse waves

Abstract

The utility model discloses an electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse waves, which comprises a probe shell, a magnet and a sound insulation layer, the magnet and the sound insulation layer are both mounted in the probe shell, and the sound insulation layer is positioned under the magnet; the probe is characterized in that the probe further comprises an orthogonal coil assembly with orthogonal axes, the orthogonal coil assembly comprises a first electromagnetic coil and a second electromagnetic coil, the first electromagnetic coil and the second electromagnetic coil are installed in the probe shell in an up-down stacked mode, and the sound insulation layer is located above the first electromagnetic coil; the axis direction of the first electromagnetic coil is parallel to the length direction of the steel rail, and eddy current generated after electrification is distributed in the width direction of the steel rail head; the axis direction of the second electromagnetic coil is perpendicular to the length direction of the steel rail, and eddy currents generated after electrification are distributed in the length direction of the steel rail. The electromagnetic ultrasonic probe based on the electromagnetic ultrasonic orthogonal transverse waves is simple in structure, high in measurement efficiency and capable of adapting to different rail head positions.

Description

TECHNICAL FIELD

[0001] The utility model relates to an electromagnetic ultrasonic probe, in particular to an electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse waves. BACKGROUND

[0002] Steel rails will produce complex stress states under the action of train load and temperature change, and abnormal accumulation of stress can lead to rail fatigue damage or even fracture, seriously affecting the safety of train operation. Therefore, it is of great significance to accurately and efficiently measure the stress of the rail.

[0003] According to the ultrasonic wave propagation characteristics of the material, the speed of ultrasonic wave propagation is different when there is tensile stress or compressive stress, and the stress direction is related to the direction of ultrasonic wave propagation vibration. When the stress direction is consistent with the ultrasonic vibration direction, the change of sound velocity has a certain proportional relationship with the change of stress, so the change of sound velocity in different directions can be used to judge whether the material is under stress.

[0004] The existing electromagnetic ultrasonic probe usually uses single direction transverse wave for measurement, which needs to adjust the probe direction multiple times to obtain stress information in different directions, and the operation is complex and the efficiency is low. In addition, some systems use multiple probes to realize multi-directional measurement, which leads to complex system structure, increased cost, and difficulty in adapting to the measurement requirements of different positions of the rail (such as rail head tread and side surface). UTILITY MODEL CONTENTS

[0005] The utility model wants to solve the problem to provide a kind of electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse wave, the structure of this kind of electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse wave is simple, and measurement efficiency is high, different rail head positions can be adapted.

[0006] In order to solve the above technical problems, the utility model adopts the technical scheme as follows:

[0007] An electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse wave, including probe shell, magnet and sound insulation layer, magnet, sound insulation layer are installed in the inside of probe shell, sound insulation layer is in the directly below of magnet;It is characterized by: still including orthogonal coil group of axis orthogonality, orthogonal coil group includes first electromagnetic coil and second electromagnetic coil, first electromagnetic coil, second electromagnetic coil are installed in the inside of probe shell and are stacked, and the sound insulation layer is above the first electromagnetic coil;The axis direction of first electromagnetic coil is parallel to the length direction of rail, and the eddy current generated after electrification is distributed along the width direction of rail head;The axis direction of second electromagnetic coil is perpendicular to the length direction of rail, and the eddy current generated after electrification is distributed along the length direction of rail.

[0008] Generally, the first electromagnetic coil and the second electromagnetic coil are made by PCB circuit printing process, and the ultrasonic frequency is determined according to the excitation frequency.

[0009] The axis direction of the first electromagnetic coil is parallel to the length direction of the rail, and the eddy current generated under the excitation of the alternating current is distributed along the width direction of the rail head, thereby exciting the first transverse wave with the vibration direction being the length direction of the rail; the axis direction of the second electromagnetic coil is perpendicular to the length direction of the rail, and the eddy current generated under the excitation of the alternating current is distributed along the length direction of the rail, thereby exciting the second transverse wave with the vibration direction being the width direction of the rail head. The propagation directions of the first transverse wave and the second transverse wave are both perpendicular downward from the center of the rail head, the vibration direction of the first transverse wave is the length direction of the rail, the vibration direction of the second transverse wave is the width direction of the rail head, and the vibration directions of the first transverse wave and the second transverse wave are perpendicular to each other to form an orthogonal relationship.

[0010] For the detection of the rail, the rail stress is mainly along the length direction of the rail, so the stress state of the rail can be judged by measuring the first transverse wave speed vibrating along the length direction of the rail and the second transverse wave speed vibrating along the width direction of the rail head. When the height of the rail is constant, the difference between the first transverse wave speed vibrating along the length direction and the second transverse wave speed vibrating along the width direction can be directly represented by measuring the difference between the propagation time of the first transverse wave vibrating along the length direction and the propagation time of the second transverse wave vibrating along the width direction. During the measurement, the electromagnetic ultrasonic probe can be placed at the center of the tread or the side surface of the rail head, and the angle of the electromagnetic ultrasonic probe can be adjusted to ensure that the vibration directions of the two groups of orthogonal transverse waves are accurately aligned with the length direction and the width direction of the rail, respectively, to meet the use requirements of different measurement positions.

[0011] The same electromagnetic ultrasonic probe simultaneously excites the two groups of orthogonal transverse waves: the propagation direction of the first transverse wave is the same as that of the second transverse wave, the vibration direction of the first transverse wave is perpendicular to that of the second transverse wave to form an orthogonal relationship, and the data required for stress evaluation can be obtained at one time without repeatedly adjusting the direction of the electromagnetic ultrasonic probe, thereby improving the measurement efficiency compared with the traditional single-direction measurement system.

[0012] In the preferred solution, the first electromagnetic coil is a wire extending in the axial direction along the length of the rail and arranged in a zigzag manner; and the second electromagnetic coil is a wire extending in the axial direction perpendicular to the length of the rail and arranged in a zigzag manner. The zigzag wire winding mode makes the alternating magnetic field generated by the coil periodically gradient distributed, compared with the traditional rectangular coil, the magnetic field strength can be improved, and the eddy current density induced on the surface of the rail is higher and more concentrated. The zigzag wire of the first electromagnetic coil (extending in the axial direction along the length of the rail) makes the eddy current strictly distributed along the width direction of the rail, avoids the diffusion of the eddy current, and ensures that the excited first transverse wave vibration direction is only the length direction of the rail. The zigzag wire of the second electromagnetic coil (extending in the axial direction perpendicular to the length of the rail) makes the eddy current strictly distributed along the length direction of the rail, and ensures that the second transverse wave vibration direction is only the width direction of the rail. When stacked up and down, the eddy current directions of the two groups of coils do not cross interfere.

[0013] In the preferred solution, the electromagnetic ultrasonic probe further comprises a probe upper cover, a probe wire clamp, a probe wire, a lead wire and a protective sheet, the probe shell is in a cylindrical shape, the probe upper cover is installed at the top of the probe shell and covers the upper opening of the probe shell, the probe upper cover is provided with a wire outlet, the probe wire clamp is fixed at the wire outlet and fixes the probe wire, the lead wire is arranged in the probe shell, one end of the lead wire is welded on the electrodes of the first electromagnetic coil and the second electromagnetic coil respectively, the other end of the lead wire extends to the wire outlet and is connected with the probe wire, and the protective sheet is installed at the lower end of the probe shell and covers the lower opening of the probe shell, and the second electromagnetic coil is above the protective sheet. The lead wire connects the first electromagnetic coil and the second electromagnetic coil with an external signal processing device to realize signal transmission.

[0014] In the preferred solution, the magnet is a permanent magnet. The permanent magnet is made of neodymium iron boron material and provides a uniform static magnetic field.

[0015] Compared with the prior art, the utility model has the following advantages:

[0016] (1) Compared with the traditional single-direction transverse wave measurement which needs to adjust the probe direction multiple times to obtain multi-dimensional stress information, the utility model synchronously excites the first transverse wave and the second transverse wave which are orthogonal through the same electromagnetic ultrasonic probe, and the complete signal required for stress evaluation can be obtained at one time, without the need of repeatedly adjusting the position of the electromagnetic ultrasonic probe, thereby shortening the measurement time and simplifying the operation process.

[0017] (2) The electromagnetic ultrasonic probe of the utility model is compact in design, and only needs to be attached to the center of the tread or the side surface of the rail head during measurement, without the need of adapting special tooling, and is compatible with the measurement requirements of different positions of the rail, thereby improving the universality and solving the pain point of poor adaptability of the traditional system single probe. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1is a schematic view of the embodiment of the utility model;

[0019] Figure 2 is a schematic view of the first electromagnetic coil of the embodiment of the utility model;

[0020] Figure 3 is a schematic view of the second electromagnetic coil of the embodiment of the utility model;

[0021] Figure 4 is a schematic view of the first electromagnetic coil and the second electromagnetic coil being stacked up and down on the rail head tread of the embodiment of the utility model;

[0022] Figure 5 is a schematic view of the electromagnetic ultrasonic probe being attached to the center position of the rail head side of the steel rail of the embodiment of the utility model. DETAILED DESCRIPTION

[0023] The utility model will be specifically described below in combination with the drawings and specific embodiments.

[0024] As Figures 1-5 shown, the electromagnetic ultrasonic probe based on electromagnetic ultrasonic orthogonal transverse wave in the embodiment includes probe shell 1, magnet 2, sound insulation layer 3 and axis orthogonal orthogonal coil group 4, magnet 2, sound insulation layer 3 are installed in the inside of probe shell 1, and sound insulation layer 3 is directly below magnet 2;Orthogonal coil group 4 includes first electromagnetic coil 41 and second electromagnetic coil 42, and first electromagnetic coil 41 and second electromagnetic coil 42 are stacked up and down and installed in the inside of probe shell 1, and sound insulation layer 3 is above first electromagnetic coil 41;The axis direction of first electromagnetic coil 41 is parallel with the length direction of rail 5, and the eddy current generated after electrification is distributed along the width direction of rail head 51 of rail 5;The axis direction of second electromagnetic coil 42 is perpendicular to the length direction of rail 5, and the eddy current generated after electrification is distributed along the length direction of rail 5.

[0025] Generally, the above-mentioned first electromagnetic coil 41 and second electromagnetic coil 42 are made by PCB circuit printing process, and the ultrasonic frequency is determined according to the excitation frequency.

[0026] The axis direction of the first electromagnetic coil 41 is parallel to the length direction of the rail 5, and the eddy current generated under the excitation of the alternating current is distributed along the width direction of the rail head 51 of the rail 5, and further excites the first transverse wave with the vibration direction being the length direction of the rail 5; the axis direction of the second electromagnetic coil 42 is perpendicular to the length direction of the rail 5, and the eddy current generated under the excitation of the alternating current is distributed along the length direction of the rail 5, and further excites the second transverse wave with the vibration direction being the width direction of the rail head 51 of the rail 5. The propagation directions of the first transverse wave and the second transverse wave are both perpendicular to the center of the rail head 51 of the rail 5, the vibration direction of the first transverse wave is the length direction of the rail 5, the vibration direction of the second transverse wave is the width direction of the rail head 51 of the rail 5, and the vibration directions of the first transverse wave and the second transverse wave are perpendicular to each other to form an orthogonal relationship.

[0027] For the detection of the rail 5, the stress of the rail 5 is mainly along the length direction of the rail 5, so the stress state of the rail 5 can be judged by measuring the first transverse wave speed vibrating along the length direction of the rail 5 and the second transverse wave speed vibrating along the width direction of the rail head 51 of the rail 5. When the height of the rail 5 is constant, the difference between the first transverse wave speed vibrating along the length direction and the second transverse wave speed vibrating along the width direction can be directly represented by measuring the difference between the propagation time of the first transverse wave vibrating along the length direction and the propagation time of the second transverse wave vibrating along the width direction. When measuring, the electromagnetic ultrasonic probe can be placed at the center of the tread or the side surface of the rail head 51 of the rail 5, and the angle of the electromagnetic ultrasonic probe is adjusted to ensure that the vibration directions of the two groups of orthogonal transverse waves are accurately aligned with the length direction and the width direction of the rail 5, respectively, to meet the use requirements of different measurement positions.

[0028] The same electromagnetic ultrasonic probe excites the two groups of orthogonal transverse waves synchronously: the propagation direction of the first transverse wave is the same as that of the second transverse wave, the vibration direction of the first transverse wave is perpendicular to that of the second transverse wave to form an orthogonal relationship, and the data required for stress evaluation can be obtained at one time, without the need for repeated adjustment of the direction of the electromagnetic ultrasonic probe. Compared with the traditional single-direction measurement system, the measurement efficiency is improved.

[0029] The first electromagnetic coil 41 is a wire extending along the length direction of the rail 5 in the axial direction and arranged in a zigzag manner, and the second electromagnetic coil 42 is a wire extending in the axial direction perpendicular to the length direction of the rail 5 and arranged in a zigzag manner. The zigzag winding of the wire causes the alternating magnetic field generated by the coil to be periodically gradient-distributed, and compared with the traditional rectangular coil, the magnetic field strength can be improved, and the eddy current density induced on the surface of the rail 5 is higher and more concentrated. The zigzag wire of the first electromagnetic coil 41 (extending along the length direction of the rail 5 in the axial direction) causes the eddy current to be strictly distributed along the width direction of the rail 5, avoids the diffusion of the eddy current, and ensures that the first transverse wave vibration direction is only the length direction of the rail 5. The zigzag wire of the second electromagnetic coil 42 (extending in the axial direction perpendicular to the length direction of the rail 5) causes the eddy current to be strictly distributed along the length direction of the rail 5, and ensures that the second transverse wave vibration direction is only the width direction of the rail 5. When stacked up and down, the eddy current directions of the two groups of coils do not cross interfere.

[0030] The electromagnetic ultrasonic probe further comprises a probe upper cover 6, a probe wire clamp 7, a probe wire 8, a lead wire 9 and a protective sheet 10. The probe shell 1 is in a cylindrical shape, the probe upper cover 6 is installed at the top of the probe shell 1 and covers the upper opening of the probe shell 1; the probe upper cover 6 is provided with a wire outlet 61, the probe wire clamp 7 is fixed at the wire outlet 61 and fixes the probe wire 8, the lead wire 9 is arranged in the probe shell 1, and one end of the lead wire 9 is respectively welded on the electrodes of the first electromagnetic coil 41 and the second electromagnetic coil 42, the other end of the lead wire 9 extends to the wire outlet 61 and is connected with the probe wire 8; the protective sheet 10 is installed at the lower end of the probe shell 1 and covers the lower opening of the probe shell 1, and the second electromagnetic coil 42 is above the protective sheet 10. The lead wire 9 connects the first electromagnetic coil 41 and the second electromagnetic coil 42 with external signal processing equipment to realize signal transmission.

[0031] The magnet 2 is a permanent magnet. The permanent magnet is made of neodymium iron boron material and provides a uniform static magnetic field.

[0032] In addition, it should be noted that the specific embodiments described in the specification can have different part names, and any equivalent or simple changes made in accordance with the structure, features and principles described in the patent concept of the present application are included in the protection scope of the present application. Those skilled in the art of the present application can make various modifications or supplements or use similar ways to replace the described specific embodiments, as long as they do not deviate from the structure of the present application or exceed the scope defined in the present claims, and they should belong to the protection scope of the present application.

Claims

1. An electromagnetic acoustic probe based on electromagnetic acoustic quasi-shear waves, comprising a probe shell, a magnet and a sound insulation layer, the magnet and the sound insulation layer are both installed inside the probe shell, and the sound insulation layer is directly below the magnet; characterized in that: The orthogonal coil group includes a first electromagnetic coil and a second electromagnetic coil, the first electromagnetic coil and the second electromagnetic coil are arranged in the inside of the probe shell in a top-bottom manner, and the sound insulation layer is above the first electromagnetic coil; the axis direction of the first electromagnetic coil is parallel to the length direction of the rail, and the eddy current generated after electrification is distributed along the width direction of the rail head; the axis direction of the second electromagnetic coil is perpendicular to the length direction of the rail, and the eddy current generated after electrification is distributed along the length direction of the rail.

2. The electromagnetic acoustic probe based on electromagnetic acoustic quasi-shear waves according to claim 1, characterized in that: The first electromagnetic coil is a wire extending in the length direction of the rail in an axial direction and distributed in a zigzag shape; and the second electromagnetic coil is a wire extending in a direction perpendicular to the length direction of the rail in an axial direction and distributed in a zigzag shape.

3. The electromagnetic acoustic transducer based on the electromagnetic ultrasonic quasi-shear wave of claim 1, wherein: The probe shell is in a cylindrical shape, the probe upper cover is arranged at the top of the probe shell and covers the upper opening of the probe shell; the probe upper cover is provided with a wire outlet, the probe wire clamp is fixed at the wire outlet and fixes the probe wire, the lead wire is arranged in the probe shell, one end of the lead wire is welded to the electrode of the first electromagnetic coil and the second electromagnetic coil respectively, the other end of the lead wire extends to the wire outlet and is connected with the probe wire, and the protective sheet is arranged at the lower end of the probe shell and covers the lower opening of the probe shell, the second electromagnetic coil is above the protective sheet.

4. The electromagnetic acoustic transducer based on the electromagnetic ultrasonic quasi-shear wave of claim 1, wherein: The magnet is a permanent magnet.

Images