Acoustic Detection Device for Interface Failure of Epoxy Inserts under Thermal and Mechanical Stresses

Abstract

The present invention provides an acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses, comprising a first clamping part, a second clamping part, a tensile stress application module, an acoustic sensor, a temperature sensor, a temperature controller, a ring heater, a tensile stress application module and a data processing module; the first clamping part clamps the epoxy resin, and the second clamping part clamps the metal insert; the ring heater surrounds the epoxy insert interface; the temperature sensor measures the temperature of the epoxy insert interface; the temperature controller adjusts the power of the heater; the tensile stress application module applies stress to the epoxy insert interface; the acoustic sensor collects interface signals; the data processing module processes the acoustic signals and determines the content of high-frequency signals to judge whether the epoxy insert interface fails. By analyzing the acoustic law, the present invention obtains the interface performance of epoxy-metal inserts under thermal and mechanical stresses, and compared with the technical solutions of the prior art, it can effectively improve the accuracy of detection and lay a foundation for the detection of various devices.

Description

Technical Field

[0001] The present invention relates to the field of epoxy insert detection, and in particular to an acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses. Background Art

[0002] Epoxy resin has excellent thermal, mechanical, and electrical properties and is widely used in high-voltage power equipment. However, due to the poor wettability between the epoxy casting system and the metal insert, the bonding between the insert and the epoxy casting material is not ideal. The weak link in the mechanical properties of epoxy cast insulators lies in the joint between the metal insert and the epoxy casting material.

[0003] Currently, the existing technology mainly relies on the structural data of the insert and then detects the performance of the interface between the epoxy resin and the metal insert (interface) based on the principle of ultrasonic critically refracted longitudinal wave detection. However, it lacks consideration of the influence of thermal and mechanical effects on the interface performance, and there is insufficient understanding of the failure law and characteristics of the interface, which will affect the accuracy of the detection results to a certain extent. Therefore, there is an urgent need for a detection device that can consider the interface performance of epoxy inserts under thermal and mechanical stresses. Summary of the Invention

[0004] The present invention provides an acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses to solve the technical problem of how to improve the accuracy of interface failure detection.

[0005] To solve the above technical problem, an embodiment of the present invention provides an acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses, including a first clamping portion, a second clamping portion, a tensile stress application module, an acoustic sensor, a temperature sensor, a temperature controller, a ring heater, a tensile stress application module, and a data processing module; wherein,

[0006] The first clamping portion and the second clamping portion are respectively provided at opposite ends of the acoustic detection device; one end of the first clamping portion clamps the epoxy resin, and one end of the second clamping portion clamps the metal insert; during the detection, the epoxy resin is cast on the metal insert to form an epoxy insert interface;

[0007] The ring heater surrounds the epoxy insert interface and is used to heat the epoxy insert interface;

[0008] The temperature sensor is used to measure the temperature of the epoxy insert interface in real time;

[0009] The temperature controller is used to adjust the heating power of the ring heater according to the real-time temperature of the epoxy insert interface measured by the temperature sensor so that the temperature of the epoxy insert interface reaches a preset value;

[0010] The tensile stress application module is connected to the other end of the first clamping part, and is used to apply mechanical stress to the epoxy resin so as to act on the epoxy insert interface;

[0011] The acoustic sensor is used to collect the acoustic signal of the epoxy insert interface;

[0012] The data processing module is used to perform wavelet transform on the acoustic signal, and perform integration respectively with 20 kHz as the demarcation line to obtain a high-frequency signal and a low-frequency signal; according to the content of the high-frequency signal, judge whether the epoxy insert interface fails; when the content of the high-frequency signal is higher than a preset threshold, judge that the epoxy insert interface has a failure phenomenon; otherwise, judge that the epoxy insert interface does not have a failure phenomenon.

[0013] As a preferred solution, the acoustic detection device further includes a fixing component, the fixing component is made of metal, and one end of the fixing component is connected to the other end of the second clamping part, and the other end of the fixing component is connected to the ground or the wall.

[0014] As a preferred solution, the second clamping component adopts a bolt structure, and the clamping radius range of the bolt structure is 5 to 15 cm; the first clamping component adopts a metal clamping rod.

[0015] As a preferred solution, the acoustic sensor adopts an optical microphone, and the detection frequency band of the optical microphone is 10 Hz to 10 MHz.

[0016] As a preferred solution, the tensile stress application module adopts a universal testing machine, and the universal testing machine is used to apply mechanical stress to the epoxy resin according to the set tensile stress magnitude and action time.

[0017] As a preferred solution, the temperature controller adopts an OHR-A103 series three-position single-loop digital display controller.

[0018] As a preferred solution, the ring heater adopts a cast copper heating coil.

[0019] As a preferred solution, the temperature sensor adopts a PT100 sensor.

[0020] As a preferred solution, the epoxy resin adopts a composite material filled with alumina.

[0021] As a preferred solution, the metal insert adopts an aluminum material.

[0022] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0023] An acoustic detection device for the interface failure of an epoxy insert under thermal and mechanical stresses provided by an embodiment of the present invention includes a first clamping part, a second clamping part, a tensile stress application module, a sound sensor, a temperature sensor, a temperature controller, a ring heater, a tensile stress application module, and a data processing module. Among them, the first clamping part and the second clamping part are respectively arranged at opposite ends of the acoustic detection device. One end of the first clamping part clamps the epoxy resin, and one end of the second clamping part clamps the metal insert. During the detection process, the epoxy resin is poured onto the metal insert to form an epoxy insert interface. The ring heater surrounds the epoxy insert interface and is used to heat the epoxy insert interface. The temperature sensor is used to measure the temperature of the epoxy insert interface in real time. The temperature controller is used to adjust the heating power of the ring heater according to the real-time temperature of the epoxy insert interface measured by the temperature sensor, so that the temperature of the epoxy insert interface reaches a preset value. The tensile stress application module is connected to the other end of the first clamping part and is used to apply mechanical stress to the epoxy resin to act on the epoxy insert interface. The sound sensor is used to collect the sound signal of the epoxy insert interface. The data processing module is used to perform wavelet transform on the sound signal and integrate it separately with 20 kHz as the dividing line to obtain a high-frequency signal and a low-frequency signal. According to the content of the high-frequency signal, it is judged whether the epoxy insert interface fails. When the content of the high-frequency signal is higher than a preset threshold, it is judged that there is a failure phenomenon in the epoxy insert interface; otherwise, it is judged that there is no failure phenomenon in the epoxy insert interface. By applying thermal and mechanical stresses to the epoxy insert, the present invention can analyze the acoustic law and obtain the interface performance of the epoxy-metal insert under thermal and mechanical stresses. Compared with the technical solutions of the prior art, the simulation under thermal and mechanical stress conditions can be carried out, effectively improving the accuracy of detection and laying a foundation for the detection of equipment such as insulators. Description of the Drawings

[0024] Figure 1 : A schematic structural diagram of an embodiment of an acoustic detection device for the interface failure of an epoxy insert under thermal and mechanical stresses provided by the present invention.

[0025] In the figure: 1 - fixed component; 2 - second clamping part; 3 - metal insert; 4 - epoxy resin; 5 - ring heater; 6 - temperature sensor; 7 - temperature controller; 8 - first clamping part; 9 - tensile stress application module; 10 - sound sensor; 11 - data processing module. Detailed Embodiments

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] Embodiment 1:

[0028] Please refer to Figure 1 , Figure 1 , which is an acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses provided by an embodiment of the present invention. It includes a fixing component 1, a first clamping part 8, a second clamping part 2, a tensile stress application module 9, a sound sensor 10, a temperature sensor 6, a temperature controller 7, a ring heater 5, a tensile stress application module 9, and a data processing module 11. Among them, in this embodiment, an aluminum material is used as the metal insert 3, and a composite material filled with alumina is used as the epoxy resin 4.

[0029] The first clamping part 8 and the second clamping part 2 are respectively arranged at opposite ends of the acoustic detection device. One end of the first clamping part 8 clamps the epoxy resin 4, and one end of the second clamping part 2 clamps the metal insert 3. During the detection process, the epoxy resin 4 is poured on the metal insert 3 to form an epoxy insert interface.

[0030] The ring heater 5 surrounds the epoxy insert interface and is used to heat the epoxy insert interface.

[0031] The temperature sensor 6 is used to measure the temperature of the epoxy insert interface in real time.

[0032] The temperature controller 7 is used to adjust the heating power of the ring heater 5 according to the real-time temperature of the epoxy insert interface measured by the temperature sensor 6, so that the temperature of the epoxy insert interface reaches a preset value.

[0033] The tensile stress application module 9 is connected to the other end of the first clamping part 8 and is used to apply mechanical stress to the epoxy resin 4 to act on the epoxy insert interface.

[0034] The sound sensor 10 is used to collect the sound signal of the epoxy insert interface.

[0035] The data processing module 11 is used to perform wavelet transform on the acoustic signal, and perform integration respectively with 20 kHz as the demarcation line to obtain a high-frequency signal and a low-frequency signal; judge whether the epoxy insert interface fails according to the content of the high-frequency signal; when the content of the high-frequency signal is higher than a preset threshold, judge that the epoxy insert interface has a failure phenomenon; otherwise, judge that the epoxy insert interface does not have a failure phenomenon.

[0036] In this embodiment, the fixing component 1 is made of metal, and one end of the fixing component 1 is connected to the other end of the second clamping portion 2, and the other end of the fixing component 1 is connected to the ground or the wall surface. The setting method of the fixing component 1 can keep the detection device stationary and prevent slight shaking of the detection device during the detection process (for example, during the process of pouring the epoxy resin 4 onto the metal insert 3), which may affect the detection result.

[0037] Further, the first clamping portion 8 is made of a high-strength metal clamping rod, and the tensile stress application module 9 is connected to one end of the metal clamping rod (the other end relative to the epoxy resin 4), then mechanical stress can be applied to the metal clamping rod, that is, mechanical stress is indirectly applied to the epoxy resin 4 to act on the epoxy insert interface. The clamping radius of the metal clamping rod can be adjusted through both ends of the rod.

[0038] The second clamping portion 2 is clamped by a bolt structure (bolt structures are provided on both sides of the metal insert 3 and can be adjusted), and the bolt structure applies pressure to both ends of the metal insert 3 to achieve the purpose of fixing the metal insert 3, so that the detection device and the second clamping portion 2 remain relatively stationary; the clamping radius range of the bolt structure is 5 to 15 cm, and relevant technicians can adjust the telescopic degree of the bolt structure to match metal inserts of different sizes, which is targeted for different types, models or diameters of metal inserts.

[0039] Preferably, the tensile stress application module 9 uses a universal testing machine, which can set the magnitude and action time of the tensile stress, and apply mechanical stress to the epoxy resin 4 according to the set magnitude and action time of the tensile stress. By adjusting different magnitudes of the tensile stress and the duration of the application of the tensile stress, mechanical stresses under different conditions can be simulated, and by comprehensively understanding the acoustic laws of the epoxy insert under different environments, the purpose of further improving the detection accuracy can be achieved.

[0040] The temperature controller 7 uses an OHR-A103 series three-position single-loop digital display controller, which can increase the power of the ring heater 5 correspondingly by reading the displayed readings to maintain the stability of the interface temperature.

[0041] The annular heater 5 uses a cast copper heating coil, and it is wrapped around the interface between the metal insert 3 and the epoxy resin 4, which can achieve uniform heating of the interface. The temperature sensor 6 uses a PT100 sensor, which is arranged near the interface between the epoxy resin 4 and the metal insert 3 to detect the temperature at the interface.

[0042] Further, the acoustic sensor 10 uses an optical microphone, which can detect the entire audio bandwidth that can be physically transmitted through air. The detection frequency band of the optical microphone is from 10 Hz to 10 MHz, and it can collect and receive the acoustic signals at the interface between the metal insert 3 and the epoxy resin 4.

[0043] For the acoustic signal data collected by the acoustic sensor 10, the data processing module 11 in this embodiment (for example, it can be preferably a high-performance computer) will first perform wavelet transform on it for noise reduction processing; further, perform Fourier transform on the noise-reduced acoustic signal to obtain the spectrum of the acoustic signal, and then integrate the signals on and below the 20 kHz boundary line respectively to obtain high-frequency signals and low-frequency signals; furthermore, it can be determined whether the epoxy insert interface fails according to the content of the high-frequency signal (for example, expressed by percentage); for example, when the content of the high-frequency signal is higher than the preset threshold, it is determined that there is a failure phenomenon at the epoxy insert interface; otherwise, it is determined that there is no failure phenomenon at the epoxy insert interface. It should be noted that the cracking of the interface between the epoxy resin 4 and the metal insert will excite broadband signals, and during normal operation, the environmental noise is in the audible range. Therefore, by extracting the high-frequency components in the detected acoustic signals, when the content of the high-frequency components reaches a certain level, the interference of environmental noise can be determined and filtered out. At the same time, the content of the high-frequency components can be used as a parameter to judge the interface performance between the epoxy resin 4 and the metal insert 3. When it is judged that the content of the high-frequency components is high, it can be judged that the interface has been damaged, that is, a failure phenomenon has occurred. On the contrary, the interface performance has not failed and is still in a normal state.

[0044] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0045] An acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses provided by an embodiment of the present invention includes a first clamping portion, a second clamping portion, a tensile stress application module, a sound sensor, a temperature sensor, a temperature controller, a ring heater, a tensile stress application module, and a data processing module. Among them, the first clamping portion and the second clamping portion are respectively provided at opposite ends of the acoustic detection device. One end of the first clamping portion clamps epoxy resin, and one end of the second clamping portion clamps a metal insert. During the detection process, the epoxy resin is poured on the metal insert to form an epoxy insert interface. The ring heater surrounds the epoxy insert interface and is used to heat the epoxy insert interface. The temperature sensor is used to measure the temperature of the epoxy insert interface in real time. The temperature controller is used to adjust the heating power of the ring heater according to the real-time temperature of the epoxy insert interface measured by the temperature sensor so that the temperature of the epoxy insert interface reaches a preset value. The tensile stress application module is connected to the other end of the first clamping portion and is used to apply mechanical stress to the epoxy resin to act on the epoxy insert interface. The sound sensor is used to collect the sound signal of the epoxy insert interface. The data processing module is used to perform wavelet transform on the sound signal and perform integration respectively with 20 kHz as the dividing line to obtain a high-frequency signal and a low-frequency signal. According to the content of the high-frequency signal, it is judged whether the epoxy insert interface fails. When the content of the high-frequency signal is higher than a preset threshold, it is judged that there is a failure phenomenon in the epoxy insert interface; otherwise, it is judged that there is no failure phenomenon in the epoxy insert interface. By applying thermal and mechanical stresses to the epoxy insert, the present invention can analyze acoustic laws and obtain the interface performance of the epoxy-metal insert under thermal and mechanical stresses. Compared with the technical solutions of the prior art, the simulation under thermal and mechanical stress conditions is carried out, which can effectively improve the accuracy of detection and lay a foundation for the detection of equipment such as insulators.

[0046] The above specific embodiments have further detailed the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. It is particularly pointed out that for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses, characterized in that, It includes a first clamping part, a second clamping part, a tensile stress application module, an acoustic sensor, a temperature sensor, a temperature controller, a ring heater, a tensile stress application module and a data processing module; among them, The first clamping part and the second clamping part are respectively arranged at opposite ends of the acoustic detection device; one end of the first clamping part clamps epoxy resin, and one end of the second clamping part clamps a metal insert; during the detection, the epoxy resin is poured on the metal insert to form an epoxy insert interface; The ring heater surrounds and encloses the epoxy insert interface and is used to heat the epoxy insert interface; The temperature sensor is used to measure the temperature of the epoxy insert interface in real time; The temperature controller is used to adjust the heating power of the ring heater according to the real-time temperature of the epoxy insert interface measured by the temperature sensor, so that the temperature of the epoxy insert interface reaches a preset value; The tensile stress application module is connected to the other end of the first clamping part and is used to apply mechanical stress to the epoxy resin to act on the epoxy insert interface; The acoustic sensor is used to collect the acoustic signal of the epoxy insert interface; The data processing module is used to perform wavelet transform on the acoustic signal and integrate it separately with 20 kHz as the dividing line to obtain a high-frequency signal and a low-frequency signal; according to the content of the high-frequency signal, judge whether the epoxy insert interface fails; when the content of the high-frequency signal is higher than the preset threshold, judge that there is a failure phenomenon at the epoxy insert interface; otherwise, judge that there is no failure phenomenon at the epoxy insert interface.

2. The acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses as described in claim 1, characterized in that, The acoustic detection device further includes a fixing component. The fixing component is made of metal, and one end of the fixing component is connected to the other end of the second clamping part, and the other end of the fixing component is connected to the ground or the wall.

3. An acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses as described in claim 1, characterized in that, The second clamping component adopts a bolt structure, and the clamping radius range of the bolt structure is 5 to 15 cm; the first clamping component adopts a metal clamping rod.

4. An acoustic detection device for epoxy insert interface failure under thermal and mechanical stresses as described in claim 1, characterized in that, The acoustic sensor adopts an optical microphone, and the detection frequency band of the optical microphone is 10 Hz to 10 MHz.

5. The acoustic detection device for epoxy insert interface failure under thermal and mechanical stresses according to claim 1, characterized in that, The tensile stress application module adopts a universal testing machine, and the universal testing machine is used to apply mechanical stress to the epoxy resin according to the set tensile stress magnitude and action time.

6. The acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses according to claim 1, characterized in that, The temperature controller adopts an OHR-A103 series three-position single-loop digital display controller.

7. An acoustic detection device for interfacial failure of epoxy inserts under thermal and mechanical stresses according to claim 1, characterized in that, The ring heater adopts a cast copper heating coil.

8. An acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses as described in claim 1, characterized in that, The temperature sensor adopts a PT100 sensor.

9. An acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses as described in claim 1, characterized in that, The epoxy resin adopts a composite material with alumina filler.

10. An acoustic detection device for the interface failure of epoxy inserts under thermal and mechanical stresses as described in claim 1, characterized in that, The metal insert adopts an aluminum material.

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