CN206270293U - A metal pipeline defect detection device based on low-frequency electromagnetic - Google Patents

Abstract

A metal pipeline defect detection device based on low-frequency electromagnetics, consisting of a computer, an STM32 development board, a power amplifier, a first excitation coil, a second excitation coil, a first skeleton, a second skeleton, a Hall element, and a telescopic rod; computer control The STM32 development board generates a sinusoidal signal. After being amplified by the power amplifier, the signal passes through the first excitation coil and the second excitation coil respectively wound on the first bobbin and the second bobbin, and the distribution of magnetic force lines will be generated in space. When encountering metal When there is a defect on the steel pipe, the magnetic force line will overflow. The Hall element fixed on the first frame can detect the change of the magnetic field. The signal detected by the Hall element can be collected into the STM32 development board to intuitively display whether there is a defect. The utility model does not need a magnetic yoke and an oscilloscope, improves portability while ensuring detection accuracy, has the characteristics of strong operability, fast detection speed, and low cost, and can be applied to various practical projects.

Description

A metal pipeline defect detection device based on low-frequency electromagnetic

technical field

The utility model provides a metal pipeline defect detection device based on low-frequency electromagnetic, which belongs to the field of electromagnetic non-destructive detection.

Background technique

At present, my country has 880,000 kilometers of pressure pipelines, and these pressure pipelines are often made of ferromagnetic metal materials, which are very easy to cause cracks, corrosion and other damage to the pipelines under high temperature and high pressure environments, especially for pipelines used in boilers and oil transportation. , has potential leakage and explosion hazards. Once failure, leakage or explosion occurs, it is often accompanied by catastrophic accidents such as fire, poisoning, environmental pollution, radioactive pollution, etc., which will seriously affect the safety of people's lives and property, national economic operation and social stability. It is of great significance for its rapid detection and early diagnosis. Existing detection technologies have certain limitations. For example, magnetic particle detection technology must pre-process the surface of the workpiece, which may cause certain damage to the workpiece during detection; radiographic detection technology has certain radiation risks, and the detection time-consuming and costly; Ultrasonic testing technology is affected by the smoothness of the workpiece surface, and it is difficult to record the test results permanently. Magnetic flux leakage testing technology is a non-destructive testing method that uses magnetic phenomena to detect metal defects. Ease of access and other advantages.

The current magnetic flux leakage detection sensors often require a yoke, which is large in size and slow in scanning speed, and is not suitable for portability and cannot be applied to large-scale detection. The utility model designs a sensor suitable for metal pipeline defect detection, adopts the STM32 development board, has the characteristics of portability, fast scanning speed, etc., and has strong feasibility.

Contents of the invention

The purpose of the utility model is to provide a metal pipeline defect detection device based on low frequency electromagnetic. The device can apply low-frequency electromagnetics to detect defects on the exterior and interior of metal pipes. It has the characteristics of no need for a yoke, portability, fast scanning speed, and high sensitivity.

The utility model is realized through the following technical solutions: a metal pipeline defect detection device based on low-frequency electromagnetics, characterized in that: a computer (1), an STM32 development board (2), a power amplifier (3), a first excitation coil (4 ), the second excitation coil (5), the first skeleton (6), the second skeleton (7), the Hall element (8) and the telescopic rod (10); the computer (1) controls the STM32 development board (2) to generate After a sinusoidal signal is amplified by the power amplifier (3), the signal passes through the first exciting coil (4) and the second exciting coil (5) respectively wound on the first bobbin (6) and the second bobbin (7), The distribution of magnetic field lines will be generated in space. When a defect on the metal steel pipe (9) is encountered, the magnetic field lines will overflow. The Hall element (8) fixed on the first frame (6) can detect the change of the magnetic field, and the Hall The signal detected by the component (8) is collected into the STM32 development board (2) to visually display whether there is a defect.

The low-frequency electromagnetic-based metal pipeline defect detection device is characterized in that: the generation of the excitation signal and the processing of the signal are completed by the STM32 development board (2).

The low-frequency electromagnetic-based metal pipeline defect detection device is characterized in that the excitation frequency is 0-100 Hz.

The metal pipeline defect detection device based on low-frequency electromagnetics is characterized in that: the Hall element (8) adopts SS94A1F, and the lift-off height is 0.1-1mm.

The working principle of the utility model is: the utility model uses the principle of electromagnetic induction to detect the surface and buried defects of the tested equipment in a non-contact manner. The coil will generate an alternating magnetic field at a lower frequency and penetrate the tested material. , to detect defects by observing the changes in the strength of the signal generated by the electromagnetic field. First, the computer (1) controls the STM32 development board (2) to generate a sinusoidal signal, and after being amplified by the power amplifier (3), the signal passes through the first excitation respectively wound on the first skeleton (6) and the second skeleton (7). After the coil (4) and the second excitation coil (5), the distribution of magnetic force lines will be generated in space. When a defect on the metal steel pipe (9) is encountered, the magnetic force lines will overflow, and the Hall fixed on the first frame (6) The element (8) can detect the change of the magnetic field, and collecting the signal detected by the Hall element (8) into the STM32 development board (2) can visually display whether there is a defect.

The beneficial effects of the utility model are: the metal pipeline defect detection device based on low-frequency electromagnetics is not affected by environmental factors such as time and space, and has the characteristics of no need for a yoke, portability, fast scanning speed, and high sensitivity.

Description of drawings

Fig. 1 is a metal pipeline defect detection device based on low frequency electromagnetic of the present invention.

Fig. 2 is a diagram of signal detection results of the utility model with or without defects.

detailed description

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail.

Referring to accompanying drawing 1, a kind of metal pipeline defect detection device based on low-frequency electromagnetic, is characterized in that: by computer (1), STM32 development board (2), power amplifier (3), the first exciting coil (4), the second The excitation coil (5), the first skeleton (6), the second skeleton (7), the Hall element (8) and the telescopic rod (10); the computer (1) controls the STM32 development board (2) to generate a sinusoidal signal, After being amplified by the power amplifier (3), the signal will generate The distribution of magnetic force lines, when encountering a defect on the metal steel pipe (9), the magnetic force lines will overflow, and the Hall element (8) fixed on the first frame (6) can detect the change of the magnetic field, and the Hall element (8) The detected signal is collected into the STM32 development board (2) to visually display whether there is a defect.

Among them, the frequency range generated by the STM32 development board (2) is 0-100Hz, the Hall element (8) adopts SS94A1F, and the lift-off height is 0.1-1mm, and the first skeleton (6) and the second skeleton (7) pass through the telescopic rod (10) connection, the first exciting coil (4) is connected in series with the second exciting coil (5). Figure 2 is a diagram of signal detection results with or without defects.

Claims (4)

1. A metal pipeline defect detection device based on low-frequency electromagnetics, consisting of a computer (1), an STM32 development board (2), a power amplifier (3), a first excitation coil (4), a second excitation coil (5), and a second excitation coil (5). A skeleton (6), a second skeleton (7), a Hall element (8) and a telescopic rod (10); the computer (1) controls the STM32 development board (2) to generate a sinusoidal signal, which is amplified by the power amplifier (3) Finally, after the signal passes through the first excitation coil (4) and the second excitation coil (5) respectively wound on the first frame (6) and the second frame (7), the distribution of magnetic lines of force will be generated in space. When there is a defect on the steel pipe (9), the magnetic field lines will overflow, and the Hall element (8) fixed on the first frame (6) can detect the change of the magnetic field, and the signal detected by the Hall element (8) is collected into the STM32 The development board (2) can visually display whether there is a defect. 2. A metal pipeline defect detection device based on low-frequency electromagnetics according to claim 1, characterized in that: the generation of the excitation signal and the processing of the signal are completed by the STM32 development board (2). 3. A metal pipeline defect detection device based on low-frequency electromagnetics according to claim 1, wherein the excitation frequency is 0-100 Hz. 4. A metal pipeline defect detection device based on low-frequency electromagnetics according to claim 1, characterized in that the Hall element (8) is SS94A1F with a lift-off height of 0.1-1mm.