Wireless passive ultrasonic thickness gauge and method

Abstract

The application discloses a wireless passive ultrasonic thickness measuring device and method, and relates to the technical field of ultrasonic thickness measurement. In the device, the transmitting end coil is connected with a pulse transmitting unit, an electric signal detecting unit and a receiving end coil respectively; the receiving end coil is connected with a piezoelectric sensor, and the piezoelectric sensor is connected with a detected object. The device is easier to operate in use, and the spatial fault tolerance of the transmitting end and the receiving end is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ultrasonic thickness measurement, in particular to a wireless passive ultrasonic thickness measurement device and method. BACKGROUND

[0002] Thickness measurement plays an important role in industry, especially for equipment operating under high temperature and high pressure conditions such as pressure vessels and pressure pipelines. The wall thickness of the detected object is determined by thickness measurement to confirm whether the equipment is within the specified safe operating conditions and to ensure its safe operation. Ultrasonic thickness measurement is the most widely used thickness measurement method in industry. Current commonly used ultrasonic thickness measurement methods include piezoelectric ultrasonic thickness measurement and electromagnetic ultrasonic thickness measurement.

[0003] Most current ultrasonic thickness measurement implementations still require the probe to be connected to the host through a wired manner. The wired connection requires manual access to the test area to contact the probe to the surface of the measured object for implementation. For detection under the insulation layer or in high-altitude areas, there are limitations such as difficulty for personnel to approach the work or to contact the surface of the measured object. Therefore, it is necessary to pre-bury the probe on the surface of the measured object for wireless thickness measurement.

[0004] Current wireless thickness measurement mainly integrates the probe and the host together and maintains contact with the outside through wireless communication. The problems of this approach include: high complexity and cost of single-point implementation, which is difficult to use on a large scale, the service life of single-point is limited by the power supply mode of the host, and the service life will be greatly reduced when external power supply is not convenient; the volume of a single sensor is large, and it is difficult to bury under the insulation layer. The existing wireless ultrasonic thickness measurement system can overcome the above shortcomings, but the main problem of this system is the use of two transmitting coils. The main problems include: the complex mutual inductance of two transmitting coils and one receiving coil is not conducive to the frequency matching of the transmitting end and improves the quality factor of the oscillation; the transmitting end and the receiving end need to be well aligned in space during use, which makes the operation process inconvenient during use, and the spatial fault tolerance of the transmitting end and the receiving end is poor. SUMMARY

[0005] The purpose of the present application is to provide a wireless passive ultrasonic thickness measurement device and method which is easier to operate during use and improves the spatial fault tolerance of the transmitting end and the receiving end.

[0006] To achieve the above purpose, the present application provides the following solutions:

[0007] A wireless passive ultrasonic thickness measurement device, comprising:

[0008] a pulse transmitting unit, a transmitting coil, an electric signal detecting unit, a receiving coil and a piezoelectric sensor;

[0009] The transmitting end coil is connected with the pulse transmitting unit, the electric signal detecting unit and the receiving end coil respectively; the receiving end coil is connected with the piezoelectric sensor, and the piezoelectric sensor is connected with the object to be detected;

[0010] The pulse transmitting unit is used for transmitting a pulse excitation electric signal to generate a pulse electromagnetic field in the transmitting end coil; the receiving end coil is used for generating an induced pulse electric signal according to the pulse electromagnetic field, and loading the induced pulse electric signal on the piezoelectric sensor to make the piezoelectric sensor generate a mechanical pulse, the mechanical pulse is coupled into the object to be detected and reflected in the object to be detected for multiple times, the piezoelectric sensor is also used for capturing each mechanical pulse reflected by the object to be detected and converting each mechanical pulse reflected by the object to be detected to obtain a plurality of electric pulses, each electric pulse generates a plurality of pulse electromagnetic fields when loaded on the receiving end coil, and the transmitting end coil is also used for generating a plurality of induced pulse voltage signals according to the plurality of pulse electromagnetic fields generated on the receiving end coil; and the electric signal detecting unit is used for acquiring and displaying the pulse excitation electric signal and each induced pulse voltage signal generated by the transmitting end coil.

[0011] Optionally, the wireless passive ultrasonic thickness measuring device further comprises an identity recognition unit for storing the number of the piezoelectric sensor.

[0012] Optionally, the identity recognition unit is an RFID tag.

[0013] Optionally, the pulse transmitting unit is a high-voltage pulse generating circuit.

[0014] Optionally, the wireless passive ultrasonic thickness measuring device further comprises a transmitting end resonance circuit, and the transmitting end resonance circuit is connected with the transmitting end coil; the transmitting end resonance circuit is used for resonating with the transmitting end coil to improve the transmitting power and amplify the plurality of pulse electromagnetic fields generated on the receiving end coil.

[0015] A wireless passive ultrasonic thickness measuring method applied to the wireless passive ultrasonic thickness measuring device, and the method comprises:

[0016] Acquiring the pulse signal displayed by the electric signal detecting unit; the pulse signal is the pulse excitation electric signal transmitted by the pulse transmitting unit and each induced pulse voltage signal generated by the transmitting end coil;

[0017] Calculating the thickness of the object to be detected according to the pulse signal.

[0018] Optionally, the calculating the thickness of the object to be detected according to the pulse signal specifically comprises:

[0019] Obtaining the interval time of adjacent pulses according to the pulse signal.

[0020] The thickness of the object being inspected is determined by the interval between adjacent pulses.

[0021] Optionally, obtaining the thickness of the inspected object based on the interval between adjacent pulses specifically includes:

[0022] The thickness of the inspected object is calculated using the formula Δt×v=2×l, where, Δt This indicates the time interval between adjacent pulses. v The speed of mechanical wave transmission is represented by l, and the thickness of the object being inspected is represented by l.

[0023] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects: The present invention sets up a receiving coil and a transmitting coil. Compared with setting up two transmitting coils, the transmitting end of the present invention is simpler, the oscillation adjustment of the transmitting end is easier, and the spatial fault tolerance of the transmitting end and the receiving end during use is better. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the 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.

[0025] Figure 1 This is a schematic diagram of the structure of a wireless passive ultrasonic thickness measuring device provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the electrical signal detection unit provided in an embodiment of the present invention, which displays the pulse excitation electrical signal and the various induced pulse voltage signals generated by the transmitting coil. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] like Figure 1As shown, the present application provides a wireless passive ultrasonic thickness measuring device, comprising: an external transmitting measuring machine 100, a passive wireless sensor 200, wherein the external transmitting measuring machine 100 comprises: a pulse transmitting unit 102, a transmitting end coil 101 and an electric signal detecting unit 103; the passive wireless sensor 200 comprises: a receiving end coil 201 and a piezoelectric sensor 202, the transmitting end coil 101 is connected with the pulse transmitting unit 102, the electric signal detecting unit 103 and the receiving end coil 201 respectively; the receiving end coil 201 is connected with the piezoelectric sensor 202, the piezoelectric sensor 202 is connected with an object to be detected 301; the pulse transmitting unit 102 is used for transmitting a pulse excitation electric signal 401 to generate a pulse electromagnetic field 402 in the transmitting end coil 101; the receiving end coil 201 is used for generating an induced pulse electric signal 403 according to the pulse electromagnetic field 402, and loading the induced pulse electric signal 403 on the piezoelectric sensor 202 to make the piezoelectric sensor 202 generate a mechanical pulse 404, the mechanical pulse 404 is coupled into the object to be detected 301 and reflects multiple times inside the object to be detected 301; the piezoelectric sensor 202 is also used for capturing each mechanical pulse reflected by the object to be detected 301 and converting each mechanical pulse reflected by the object to be detected 301 to obtain a plurality of electric pulses 405, 406 and 407, when the electric pulses 405, 406 and 407 are loaded on the receiving end coil 201, a plurality of pulse electromagnetic fields 408, 409 and 410 are generated, the transmitting end coil 101 is also used for generating a plurality of induced pulse voltage signals 411, 412 and 413 according to the plurality of pulse electromagnetic fields 408, 409 and 410 generated on the receiving end coil 201, as shown in Figure 2 As shown, the electric signal detecting unit 103 is used for acquiring and displaying the pulse excitation electric signal 401 and each induced pulse voltage signal 411, 412 and 413 generated by the transmitting end coil 101.

[0030] As an optional embodiment, the wireless passive ultrasonic thickness measuring device further comprises: an identity recognition unit used for storing the number of the piezoelectric sensor 202, generally, the identity recognition unit is added in the passive wireless sensor 200, before detection, the external transmitting measuring machine 100 communicates with the identity recognition unit to acquire the number of the piezoelectric sensor 202, and then thickness measurement is performed. There are two ways to acquire the number, one is that the transmitting end coil communicates with the identity recognition unit, in this method, the transmitting coil respectively loads excitation pulses and communication signals through time division multiplexing. The other way is that two independent coils are used, one loads excitation pulses and the other loads communication signals of the identity recognition unit, and the current implementation is two concentric circles, wherein the outer coil excitation pulse voltage is used as a main signal for excitation and acquisition; the inner coil generates communication signals for RFID communication.

[0031] As an optional implementation, the identification unit is an RFID tag.

[0032] As an optional implementation, the pulse transmitting unit is a high-voltage pulse generating circuit.

[0033] As an optional implementation, to increase signal strength, a resonant circuit is added to the transmitting coil to generate resonance at the AC frequency of transmission or reception. The wireless passive ultrasonic thickness measurement device further includes: a transmitting resonant circuit (a set of parallel capacitors); the transmitting resonant circuit is connected to the transmitting coil (it can be connected in parallel with the transmitting coil, or in series between the transmitting coil and the pulse transmitting unit); the transmitting resonant circuit is used to generate resonance with the transmitting coil, increasing the transmission power and amplifying the multiple pulsed electromagnetic fields generated on the receiving coil. The transmitting resonant circuit is typically one or a set of capacitors, connected in series or parallel with the transmitting coil; the theoretical value of the capacitor value of the transmitting resonant circuit is determined by the LC series or LC parallel resonance formula, but in actual debugging, this value is slightly different.

[0034] The working principle of the wireless passive ultrasonic thickness measuring device provided in this embodiment of the invention is as follows:

[0035] The pulse transmitting unit 102 transmits a pulse excitation electrical signal 401, generating a pulsed electromagnetic field 402 on the transmitting coil 101. Simultaneously, the electrical signal detection unit 103 acquires the pulse excitation electrical signal 414. The pulsed electromagnetic field 402 generates an induced pulse electrical signal 403 on the receiving coil 201. This induced pulse electrical signal 403 is applied to the piezoelectric sensor 202, generating a mechanical pulse 404. The mechanical pulse 404 can be used for ultrasonic testing and thickness measurement. When the piezoelectric sensor 202 is well connected to the object under test 301, the mechanical pulse 404 is coupled into the object under test 301 and reflected at the bottom surface of the object under test 301. Figure 1As shown, the mechanical pulse is repeatedly transmitted in the detected object; when reflected to the surface of the detected object 301, it is captured by the piezoelectric sensor 202 and converted into electric pulses 405, 506 and 407, the electric pulses 405, 406 and 407 converted by the piezoelectric sensor 202 are loaded on the receiving end coil 201 to generate pulsed electromagnetic fields 408, 409 and 410, the pulsed electromagnetic fields 408, 409 and 410 generate induced pulsed voltage signals 411, 412 and 413 on the transmitting end coil 101, and the electric signal detection unit 103 can obtain the induced pulsed voltage signals 411, 412 and 413; in one detection process, the total signal 414 observed by the electric signal detection unit 103 is the superposition of signals 401, 411, 412 and 413. The time detection between signals 401, 411, 412 and 413 is the time of the mechanical pulse transmitting from the upper surface to the lower surface in the detected object and then reflecting to the upper surface; by measuring the interval time in signal 414, the thickness of the detected object can be calculated.

[0036] The embodiment of the present application also provides a wireless passive ultrasonic thickness measurement method applied to the above device, which comprises the following steps:

[0037] The pulsed signals displayed by the electric signal detection unit are obtained; the pulsed signals are the pulsed excitation electric signals transmitted by the pulsed transmission unit and the induced pulsed voltage signals generated by the transmitting end coil.

[0038] The thickness of the detected object is calculated according to the pulsed signals.

[0039] In actual application, the calculation of the thickness of the detected object according to the pulsed signals specifically comprises:

[0040] The interval time of adjacent pulses is obtained according to the pulsed signals.

[0041] The thickness of the detected object is obtained according to the interval time of adjacent pulses.

[0042] In actual application, the calculation of the thickness of the detected object according to the interval time of adjacent pulses specifically comprises:

[0043] The thickness of the detected object is calculated according to the formula Δt x v = 2 x l, wherein, Δt The interval time of adjacent pulses, v represents the mechanical wave transmission speed, and l represents the thickness of the detected object.

[0044] The present application has the following technical effects:

[0045] Compared with the traditional thickness measurement, the wireless thickness measurement can be applied to objects that are difficult for personnel to reach or contact, such as high altitude, narrow space, under thermal insulation layer, etc.

[0046] Compared with the conventional wireless ultrasonic thickness measurement technology, the sensor size of the application is smaller and easier to arrange; meanwhile, the limitation of battery is eliminated; the single point cost is significantly reduced.

[0047] Compared with the existing wireless ultrasonic thickness measurement system, the transmitting end of the application is simpler, the transmitting end oscillation adjustment is easier, and the spatial fault tolerance of the transmitting end and the receiving end during use is better.

[0048] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between various embodiments can be referred to each other. For the system disclosed by the embodiments, since it corresponds to the method disclosed by the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0049] The principles and implementation modes of the application are described by applying specific examples in this paper, and the above embodiment description is only used to help understand the method and core idea of the application; meanwhile, for the general technical personnel in the field, the specific implementation mode and application range will be changed according to the idea of the application. In conclusion, the content of the specification should not be understood as the limitation of the application.

Claims

1. A wireless passive ultrasonic thickness gauge, comprising: It comprises: a transmitting end resonance circuit, a pulse transmitting unit, a transmitting end coil, an electric signal detecting unit, a receiving end coil and a piezoelectric sensor; the transmitting end coil is connected with the pulse transmitting unit, the electric signal detecting unit and the receiving end coil respectively; the receiving end coil is connected with the piezoelectric sensor, and the piezoelectric sensor is connected with the object to be detected; the transmitting end resonance circuit is connected in parallel with the transmitting end coil, or connected in series between the transmitting end coil and the pulse transmitting unit; the transmitting end resonance circuit is used to produce resonance with the transmitting end coil, improve the transmitting power and amplify the multiple pulse electromagnetic fields generated on the receiving end coil; the pulse transmitting unit is used to transmit a pulse excitation electric signal to generate a pulse electromagnetic field in the transmitting end coil; the receiving end coil is used to generate an induced pulse electric signal according to the pulse electromagnetic field, load the induced pulse electric signal on the piezoelectric sensor to make the piezoelectric sensor generate a mechanical pulse, couple the mechanical pulse into the object to be detected and make the mechanical pulse reflect multiple times inside the object to be detected, and the piezoelectric sensor is also used to capture each mechanical pulse reflected by the object to be detected, convert each mechanical pulse reflected by the object to be detected to obtain multiple electric pulses, and generate multiple pulse electromagnetic fields when each electric pulse is loaded on the receiving end coil; the transmitting end coil is also used to generate multiple induced pulse voltage signals according to the multiple pulse electromagnetic fields generated on the receiving end coil; and the electric signal detecting unit is used to acquire and display the pulse excitation electric signal and each induced pulse voltage signal generated by the transmitting end coil.

2. The wireless passive ultrasonic thickness gauge of claim 1, wherein, It also comprises: an identity recognition unit used to store the number of the piezoelectric sensor.

3. The wireless passive ultrasonic thickness gauge of claim 2, wherein, The identity recognition unit is an RFID tag.

4. The wireless passive ultrasonic thickness gauge of claim 1, wherein, The pulse transmitting unit is a high-voltage pulse generating circuit.

5. A wireless passive ultrasonic thickness measurement method, characterized by, The method is applied to the wireless passive ultrasonic thickness measuring device of any one of claims 1-4, and the method comprises: acquiring the pulse signals displayed by the electric signal detecting unit; the pulse signals are the pulse excitation electric signal transmitted by the pulse transmitting unit and each induced pulse voltage signal generated by the transmitting end coil; calculating the thickness of the object to be detected according to the pulse signals.

6. The wireless passive ultrasonic thickness measurement method of claim 5, wherein, The calculation of the thickness of the object to be detected according to the pulse signals specifically comprises: obtaining the interval time of adjacent pulses according to the pulse signals; obtaining the thickness of the object to be detected according to the interval time of adjacent pulses.

7. The wireless passive ultrasonic thickness measurement method of claim 6, wherein, The calculation of the thickness of the object to be detected according to the interval time of adjacent pulses specifically comprises: According to the formula The thickness of the object under examination is calculated, wherein denotes the interval time of adjacent pulses, denotes the mechanical wave transmission speed, and l denotes the thickness of the object under examination.

Images