Electromagnetic ultrasonic and eddy current compound sensor and thickness gauge with same

Abstract

The application provides an electromagnetic ultrasonic and eddy current composite sensor and an electromagnetic ultrasonic and eddy current composite thickness gauge, the sensor comprising: a shell, a magnet, an electromagnetic ultrasonic coil, an eddy current coil and an interface; the electromagnetic ultrasonic coil is arranged at one end of the magnet; the eddy current coil is wound around the magnet, the eddy current coil comprises an eddy current transmitting coil and an eddy current receiving coil, the eddy current transmitting coil has P pieces, and the eddy current receiving coil has Q pieces; the interface is arranged on the shell and is electrically connected with the electromagnetic ultrasonic coil and the eddy current coil. The composite sensor provided by the application winds the eddy current transmitting coil and the eddy current receiving coil on the magnet, thereby saving the internal space of the sensor, and the structure form of the eddy current transmitting coil and the eddy current receiving coil can also weaken the influence of the magnet on the excitation and reception of the eddy current coil, thereby improving the signal-to-noise ratio during eddy current measurement data. The integration of the electromagnetic ultrasonic and eddy current technologies can also accurately and quickly measure the thickness / defects of a metal test piece and the thickness of a coating layer of the metal test piece, thereby simplifying the measurement steps.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nondestructive testing, and in particular to an electromagnetic ultrasonic and eddy current composite sensor and a thickness gauge with the same. BACKGROUND

[0002] In the production process of metal materials, due to the limitation of processing technology, it is inevitable to have uneven thickness and defects. In the process of coating the cladding layer, the cladding layer will also have uneven thickness. The cladding layer plays a key and important protective role in the long-term use of metal materials, greatly prolonging the service life of the metal materials. After being put into use, the side of the metal material without the coated cladding layer will have thickness changes, crack growth and other phenomena due to stress and corrosion, etc., affecting the service life of the metal material. Once the material is severely thinned or perforated due to corrosion, especially for pipelines and pressure vessels transporting dangerous gases and liquids, it will cause huge economic losses, and even personnel casualties.

[0003] Therefore, the defects of the metal itself and the thickness of the cladding layer directly determine the service life of the metal material. In order to avoid significant losses, a sensor capable of measuring metal defects and cladding layer thickness is needed. Traditional piezoelectric ultrasonic sensors can measure the thickness of metal samples or the thickness of the cladding layer, but they require the application of coupling agents, the replacement of probes, and the polishing of samples, which is a complicated process.

[0004] Therefore, it is necessary to provide a sensor that is fast, high-precision, does not damage the original metal material, and can measure the thickness of the metal defects and the cladding layer. SUMMARY

[0005] The present application aims to provide an electromagnetic ultrasonic and eddy current composite sensor and a thickness gauge with the same, which can accurately measure metal defects and metal material cladding layer thickness at the same time, solving the problem of low measurement efficiency and complex process in the prior art.

[0006] To achieve one of the above-mentioned purposes, an embodiment of the present application provides an electromagnetic ultrasonic and eddy current composite sensor, comprising:

[0007] a housing, a magnet arranged in the housing, an electromagnetic ultrasonic coil arranged at one end of the magnet, an eddy current coil surrounding the magnet, the eddy current coil comprising an eddy current transmitting coil and an eddy current receiving coil, the eddy current transmitting coil having P number of coils, and the eddy current receiving coil having Q number of coils, wherein P and Q are integers greater than zero, and an interface provided on the housing and electrically connected with the electromagnetic ultrasonic coil and the eddy current coil.

[0008] As a further improvement of the embodiment of the present application, the eddy current transmitting coil and the eddy current receiving coil are arranged in an alternating manner.

[0009] As a further improvement of the embodiment of the present application, P is 1, Q is 2, the eddy current transmitting coil is arranged between the two eddy current receiving coils, and the two eddy current receiving coils are connected in series.

[0010] As a further improvement of the embodiment of the present application, the distance between the eddy current transmitting coil and the eddy current receiving coil in the length direction of the magnet is less than the length of any of the eddy current coils.

[0011] As a further improvement of the embodiment of the present application, the electromagnetic ultrasonic coil has at least two, and the at least two electromagnetic ultrasonic coils are arranged in the thickness direction at one end of the magnet.

[0012] As a further improvement of the embodiment of the present application, a magnetic conducting sheet is further included, and the magnetic conducting sheet is arranged between the magnet and the electromagnetic ultrasonic coil.

[0013] As a further improvement of the embodiment of the present application, the shape of the electromagnetic ultrasonic coil includes a folded type and a spiral type, the folded type includes a back-shaped, a l-shaped, and a snake-shaped, and the spiral type includes a circular and a runway-shaped.

[0014] As a further improvement of the embodiment of the present application, the magnet is a permanent magnet or an electromagnet.

[0015] As a further improvement of the embodiment of the present application, the permanent magnet is a neodymium iron boron or a samarium cobalt.

[0016] The embodiment of the present application further provides an electromagnetic ultrasonic and eddy current composite thickness gauge, including a sensor and a host, the sensor is the aforementioned electromagnetic ultrasonic and eddy current composite sensor, and the sensor is connected with the host through the interface.

[0017] The one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0018] The embodiment of the present application integrates the electromagnetic ultrasonic and eddy current technologies, winds the eddy current coil on the magnet for providing a static magnetic field for the electromagnetic ultrasonic, saves the internal space of the sensor, and at the same time, the structure form that the eddy current coil is divided into an eddy current transmitting coil and an eddy current receiving coil can weaken the influence of the magnet on the excitation and reception of the eddy current coil, and improve the signal-to-noise ratio of the eddy current measurement data. The integration of the electromagnetic ultrasonic and eddy current technologies can also accurately and quickly measure the thickness / defect of the metal test piece and the thickness of the coating layer thereof, and does not need to polish, smear the coupling agent, and then test the surface coating layer of the metal test piece, thereby simplifying the measurement steps. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic view of the sensor and the metal test piece in the embodiment of the present application.

[0020] Figure 2 is the front structure schematic diagram of the thickness gauge in the embodiment of the present application.

[0021] Figure 3 is Figure 2 is the side structure schematic diagram of the thickness gauge in the embodiment of the present application.

[0022] Figure 4 is Figure 2 is the bottom structure schematic diagram of the thickness gauge in the embodiment of the present application.

[0023] 10, sensor; 1, magnet; 2, electromagnetic ultrasonic coil; 3, eddy current transmitting coil; 4, eddy current receiving coil; 5, magnetic conductive sheet; 6, shell; 7, interface; 8, metal test piece; 9, cladding layer; 20, main machine; 21, liquid crystal display; 22, charging indicator light; 23, operation keyboard; 24, hand rope binding port; 25, charging port. DETAILED DESCRIPTION

[0024] The present application will be described in detail below with reference to the embodiments shown in the drawings. However, these embodiments do not limit the present application, and the structural, method, or functional changes made by those skilled in the art based on these embodiments are included in the protection scope of the present application.

[0025] The terms such as "upper", "above", "lower", "below", and the like used herein to indicate spatial relative positions are used to describe the relationship of one unit or feature relative to another unit or feature as shown in the drawings for the purpose of convenience. The spatial relative position terms can be intended to include different orientations of the device in use or work other than the orientation shown in the drawings. For example, if the device in the drawing is turned over, the unit described as being "below" or "under" the other unit or feature will be "above" the other unit or feature. Therefore, the exemplary term "below" can encompass both the above and below orientations. The device can be oriented in other ways (rotated 90 degrees or other orientations), and the spatial-related descriptions used herein are interpreted accordingly.

[0026] Embodiment 1

[0027] The electromagnetic ultrasonic and eddy current composite sensor provided by the embodiment of the present application is used for measuring the thickness / defects of the metal test piece 8 and the thickness of the cladding layer 9 thereof, such as Figure 1As shown, the sensor 10 comprises: a housing 6, a magnet 1 arranged in the housing 6, an electromagnetic ultrasonic coil 2 arranged at one end of the magnet 1, an eddy current coil surrounding the magnet 1, and an interface 7 arranged on the housing 6, the eddy current coil comprising P eddy current transmitting coils 3 and Q eddy current receiving coils 4, wherein P and Q are integers greater than zero; and the interface 7 is electrically connected with the electromagnetic ultrasonic coil 2 and the eddy current coil. The eddy current coil is wound on the magnet 1 for providing a static magnetic field for the electromagnetic ultrasonic coil 2, thereby saving the internal space of the sensor 10, and the structure of the eddy current coil being divided into the eddy current transmitting coil 3 and the eddy current receiving coil 4 can weaken the influence of the magnet 1 on the excitation and reception of the eddy current coil, thereby improving the signal-to-noise ratio of the eddy current measurement data.

[0028] The shape of the housing 6 can be adjusted according to different needs, that is, the shape of the housing is not limited.

[0029] The magnet 1 of the embodiment is preferably a permanent magnet, and of course, the magnet 1 can also be selected as an electromagnet according to needs. Further preferably, the permanent magnet is a neodymium-iron-boron permanent magnet, which has stable magnetism at normal temperature, can provide a strong bias magnetic field, and is not disturbed by external mechanical vibration and electromagnetic noise and other environments, has high detection sensitivity, and improves the anti-interference ability of the sensor 10 to a certain extent. Of course, permanent magnets of different materials can be selected for different temperature scenarios, for example, a samarium-cobalt permanent magnet.

[0030] The electromagnetic ultrasonic coil 2 with an alternating current generates an alternating electric field, and the alternating electric field induces an eddy current field on the surface of the metal test piece 8. The internal particles of the metal test piece 8 are subjected to an alternating force under the action of an external static magnetic field, thereby producing mechanical vibration, generating electromagnetic ultrasonic waves, and propagating in the metal test piece 8. The return pressure makes the vibration of the measured point change the voltage at both ends of the electromagnetic ultrasonic coil 2 under the action of the magnetic field, thereby generating a return signal as the first sensing signal of the sensor 10.

[0031] The shape of the electromagnetic ultrasonic coil 2 can be a folded type or a spiral type, and the folded type includes a back-shaped, a l-shaped, and a snake-shaped, and the spiral type includes a circular shape and a racetrack shape. Different shapes of the electromagnetic ultrasonic coil 2 can cooperate with different magnets to generate different waveforms. The embodiment preferably uses a spiral electromagnetic ultrasonic coil 2 to excite electromagnetic ultrasonic transverse waves with a neodymium-iron-boron permanent magnet, and of course, any shape of the electromagnetic ultrasonic coil 2 can be selected according to needs to cooperate with a permanent magnet or an electromagnet.

[0032] When the eddy current coil is passed through the sine alternating current, the space around the eddy current coil generates the alternating magnetic field, the alternating magnetic field generates the electric eddy current in the metal test piece 8, the size of the electric eddy current changes with the distance between the aforementioned alternating magnetic field and the metal test piece 8, and the electric eddy current also generates another alternating magnetic field to generate the induced voltage in the eddy current coil, the peak value of the induced voltage can be used to judge the distance between the sensor 10 and the metal test piece 8, and the thickness information of the surface coating layer 9 of the metal test piece 8 is obtained, and the induced voltage signal is the second sensing signal of the sensor 10.

[0033] Preferably, the eddy current transmitting coil 3 and the eddy current receiving coil 4 are arranged in an alternating manner, the eddy current transmitting coil 3 and the eddy current receiving coil 4 are arranged in an alternating manner, the influence of the magnet 1 on the eddy current measurement data is smaller during measurement, the signal-to-noise ratio of the measurement data is higher, and the measurement accuracy is higher.

[0034] More preferably, P is 1 and Q is 2, that is, the eddy current transmitting coil 3 is arranged between the two eddy current receiving coils 4, and the two eddy current receiving coils 4 are connected in series, and the measurement accuracy of the coating layer 9 thickness is higher.

[0035] Further, in the length direction of the magnet 1, the distance between the eddy current transmitting coil 3 and the eddy current receiving coil 4 is less than the length of any eddy current coil.

[0036] Further, the electromagnetic ultrasonic coil 2 has at least two, and at least two electromagnetic ultrasonic coils 2 are arranged in the thickness direction on one end of the magnet 1. The superposition of the electromagnetic ultrasonic coil 2 can improve the signal-to-noise ratio of the measurement data to a certain extent, but considering the cost, the size of the space and the accuracy that can be achieved by the embodiment, the embodiment is provided with two electromagnetic ultrasonic coils 2 for superposition, but the present application is not limited to the superposition of two electromagnetic ultrasonic coils 2, and can be more, or only one electromagnetic ultrasonic coil 2.

[0037] The magnetic conductive sheet 5 is arranged between the magnet 1 and the electromagnetic ultrasonic coil 2 to strengthen the magnetic field.

[0038] The measurement range of the electromagnetic ultrasonic and eddy current composite sensor provided by the embodiment for measuring the coating layer 9 thickness of the metal test piece 8 is 0-8mm, and the measurement accuracy is 0.1mm.

[0039] Embodiment 2

[0040] The embodiment two of the present application provides an electromagnetic ultrasonic and eddy current composite thickness gauge, like Figures 2-4As shown, it comprises a sensor 10 and a host 20, the sensor 10 is the electromagnetic ultrasonic and eddy current composite sensor provided in embodiment 1, and the sensor 10 is connected to the top of the host 20 through an interface 7. The top of the host 20 is provided with a pin, and the sensor 10 is provided with a female seat, which is the interface 7 in embodiment 1, the host 20 and the sensor 10 are electrically connected through the interface 7, and the sensor 10 and the host 20 are fixedly connected through screws. The thickness gauge provided in the embodiment is integrally arranged in a pen-shaped shape, has high integration, small volume, light weight, convenient operation and is convenient to carry. Of course, the shape of the host of the thickness gauge is not limited to the shape shown in the drawing of the embodiment, and the host can also be arranged in the form of connecting the sensor 10 and the host 20 by using a wire.

[0041] The host 20 comprises a liquid crystal display 21, a charging indicator 22, an operation keyboard 23, a charging port 25 and a hand rope binding port 24. As shown in Figure 4 The charging port 25 is arranged at the bottom of the host 20, that is, at the end of the host 20 away from the sensor 10, for charging the thickness gauge, so that the thickness gauge is more convenient to operate when charging and using at the same time.

[0042] The liquid crystal display 21 is used to display the thickness / defect information of the metal test piece 8, the thickness information of the cladding layer 9, the electric quantity, the acoustic velocity, the electromagnetic ultrasonic echo original waveform, the eddy current echo original waveform, the gain, the measurement range and other related measurement information. The operation keyboard 23 is provided with keys, which are used for switching on and off the equipment, operating the display content of the liquid crystal display 21, changing the parameter setting and the like. The LED lamp on the operation keyboard 23 can also be used to display the charging state. The liquid crystal display 21, the charging indicator 22 and the operation keyboard 23 are arranged on the front surface of the host 20, so that the information can be conveniently viewed and the thickness gauge can be conveniently operated. The hand rope binding port 24 is arranged on the side surface, and of course can also be arranged on the back surface parallel to the front surface of the host 20. When measuring, the thickness gauge is prevented from falling from the hand, and the risk of accidental damage to the thickness gauge is reduced.

[0043] The electromagnetic ultrasonic and eddy current composite thickness gauge provided in the embodiment adopts the electromagnetic ultrasonic and eddy current composite sensor provided in embodiment 1 as a probe, combines electromagnetic ultrasonic and eddy current, and the two work quickly and alternately, which can be considered as working at the same time by the operator, that is, the thickness data of the metal test piece 8 and the cladding layer 9 thereof can be obtained at one time. At the same time, since the eddy current technology is adopted, the surface of the test piece does not need to be polished, and the data can be measured without using a coupling agent, which is more convenient and fast compared with the existing piezoelectric ultrasonic technology for measuring the thickness of the cladding layer 9. The host 20 is reduced and matched with the probe to form a pen-shaped thickness gauge, which is more compact and light compared with the conventional thickness gauge in which the probe and the host 20 are connected by a wire, and is convenient for the operator to detect.

[0044] In addition, when the metal test piece 8 is thin, the thickness of the cladding layer 9 measured by eddy current measurement will be inaccurate, but the aforementioned structure based on the sensor 10 can improve the accuracy of the thickness of the cladding layer 9 measured by eddy current measurement, and the thickness of the metal test piece 8 can be measured by electromagnetic acoustic testing, and the circuit in the host 20 can compensate the thickness of the cladding layer 9 measured by eddy current. At the same time, a gain amplifier can be set in the circuit of the host 20, and the thickness of the cladding layer 9 measured by eddy current can assist in setting the gain value of the amplifier when the thickness of the metal test piece 8 is measured by electromagnetic acoustic testing, so that the waveform of the electromagnetic acoustic testing can be stabilized at a suitable amplitude more quickly. The operator can further judge whether the test piece is internally corroded or externally corroded by comparing the thickness data of the cladding layer 9 measured by eddy current, the thickness data of the metal test piece 8 measured by electromagnetic acoustic testing, and the gain value of the amplifier with the original data. The electromagnetic acoustic and eddy current composite thickness gauge provided in the embodiment can also compensate for the deficiency of electromagnetic acoustic testing that cannot measure the thickness of the metal test piece 8 below 1.5 mm. The electromagnetic acoustic and eddy current composite thickness gauge provided in the present application can make the eddy current and electromagnetic acoustic complement each other and cooperate with each other to improve the accuracy and efficiency.

[0045] It should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that those skilled in the art can understand.

[0046] The above series of detailed descriptions are only specific descriptions of the feasible embodiments of the present application, and are not intended to limit the protection scope of the present application, and any equivalent embodiments or changes made without departing from the spirit of the present application should be included in the protection scope of the present application.

Claims

1. An electromagnetic ultrasonic and eddy current compound sensor, characterized in that, The electromagnetic ultrasonic and eddy current composite sensor comprises: a housing; a magnet arranged in the housing; an electromagnetic ultrasonic coil arranged at one end of the magnet; an eddy current coil surrounding the magnet, the eddy current coil comprising one eddy current transmitting coil and two eddy current receiving coils, the eddy current transmitting coil and the eddy current receiving coils being arranged in an alternating manner, and the eddy current transmitting coil being arranged between the two eddy current receiving coils, the two eddy current receiving coils being connected in series; an interface arranged on the housing and electrically connected with the electromagnetic ultrasonic coil and the eddy current coil.

2. The electromagnetic ultrasonic and eddy current compound sensor of claim 1, wherein, In the length direction of the magnet, the distance between the eddy current transmitting coil and the eddy current receiving coil is less than the length of any eddy current coil.

3. The electro-magnetic ultrasonic and eddy current compound sensor of claim 1, wherein, The electromagnetic ultrasonic coil has at least two, and the at least two electromagnetic ultrasonic coils are arranged in a stacked manner in the thickness direction at one end of the magnet.

4. The electro-magnetic ultrasonic and eddy current compound sensor of claim 1, wherein, A magnetic conducting sheet is further arranged between the magnet and the electromagnetic ultrasonic coil.

5. The electro-magnetic ultrasonic and eddy current compound sensor of claim 1, wherein, The shape of the electromagnetic ultrasonic coil comprises a folded type and a spiral type, the folded type comprising a back-shaped, a l-shaped and a snake-shaped, and the spiral type comprising a circular and a racetrack-shaped.

6. The electro-magnetic ultrasonic and eddy current compound sensor of claim 1, wherein, The magnet is a permanent magnet or an electromagnet.

7. An electromagnetic ultrasonic and eddy current compound thickness gauge characterized by, The electromagnetic ultrasonic and eddy current composite sensor further comprises a sensor and a host, the sensor being the electromagnetic ultrasonic and eddy current composite sensor according to any one of claims 1-6, and the sensor being connected with the host through the interface.

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