A method and device for detecting defects of pipe elbows based on far-field eddy currents

A pipeline elbow, far-field eddy current technology, applied in the direction of material magnetic variables, can solve pipeline elbow defects, pipeline elbow detection and other problems, achieve the same sensitivity, easy defect identification, and reduce detection blind spots.

Inactive Publication Date: 2018-03-23
XIANGTAN UNIV
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome various deficiencies existing in the prior art, and to provide a method that utilizes double excitation to narrow the far-field area, increase the amplitude of the measured signal, fully reflect the advantages of far-field eddy current detection, and solve the problem of internal penetration. Far-field eddy current-based detection method and detection device for pipe elbow defects

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A method and device for detecting defects of pipe elbows based on far-field eddy currents
  • A method and device for detecting defects of pipe elbows based on far-field eddy currents
  • A method and device for detecting defects of pipe elbows based on far-field eddy currents

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] Embodiment 1, refer to Figure 1-3 , The shielding unit 12 is made of silicon steel sheet. The handle 10 is connected to the end cover 11 by a hexagonal screw, and the end cover 11 is connected to the housing 13 by a cross recessed pan head screw. The excitation coil 3 is fixed at both ends of the bottom of the casing, the receiving coil 4 is fixed at the center of the bottom of the casing cavity, the shielding unit 12 is covered above the excitation coil 3 , and the leads of the excitation coil 3 and the receiving coil 4 are connected to the aviation socket 9 . The far-field eddy current sensor is arranged on the cross section of the pipeline elbow 1; the excitation unit includes an excitation coil 3, and the receiving unit includes a receiving coil 4, the axis of the excitation coil 3 is arranged along the circumference of the pipeline elbow 1, and the axis of the receiving coil 4 It is arranged radially along the pipe elbow; the receiving coil 4 is located in the fa...

Embodiment 2

[0037] Example 2, see image 3 , the far-field eddy current sensor of the present invention is connected with the harmonic signal excitation circuit, signal processing circuit, A / D conversion circuit and computer successively, and the harmonic signal excitation circuit provides harmonic excitation to the far-field eddy current sensor, and the far-field eddy current sensor is set On the outer surface of the pipe elbow, the eddy current is induced by excitation and the indirect coupling magnetic field signal in the far field area of ​​the eddy current is received, converted into a voltage signal, and then sent to the signal processing circuit. The signal processing circuit amplifies, filters, and After comparison, it is sent to the A / D conversion circuit. The A / D conversion circuit converts the analog signal into a digital signal and sends it to the computer. The computer processes the received data to obtain the corrosion and crack defect information of the pipe elbow under test...

Embodiment 3

[0038] Embodiment 3, refer to Figure 1 to Figure 5 , the pipe elbow detection device of the present invention consists of a far-field eddy current sensor 2 composed of two identical excitation units and a receiving unit, and the two excitation units are respectively located on both sides of the receiving unit. The excitation unit includes an excitation coil 3, the receiving unit includes a receiving coil 4, the axis of the excitation coil 3 is arranged along the circumference of the pipe elbow 1, the axis of the receiving coil 4 is arranged radially along the pipe elbow, and the receiving coil 4 is located in the measuring indirect The far-field region where magnetic field signals are coupled. The far-field eddy current sensor 2 includes a housing 13, an end cover 11, an excitation coil 3, a receiving coil 4 and a socket, and the socket can adopt the structural form of an aviation socket 9, or other structural forms; the housing 13 is provided with an internal The "︹" type s...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A detection method and detection device for pipeline elbow defects based on far-field eddy currents. It mainly solves technical problems such as blind areas or poor probe passability when existing eddy current testing is used for pipe elbows. The main points of the technical solution are: adopting a far-field eddy current sensor composed of two identical excitation units and a receiving unit, and the two excitation units are respectively located on both sides of the receiving unit, and both the excitation unit and the receiving unit are located along the circumference of the elbow cross section of the detected pipeline. The receiving unit is located in the far-field area where the indirect coupled magnetic field signal is measured; when the far-field eddy current sensor is applied with harmonic excitation, the double excitation is used to narrow the far-field area and increase the measured signal amplitude; the sensor is along the circumference of the pipe elbow To scan, measure the phase difference of the signal received by the receiving unit relative to the excitation signal, so as to obtain the change characteristics of the phase difference, that is, to obtain the corrosion and crack defect information at the pipe elbow. It mainly adopts the principle of far-field eddy current and is applied to the defect detection of pipe elbows.

Description

technical field [0001] The invention relates to an electromagnetic non-destructive testing method, in particular to a method and a special device for detecting corrosion or crack defects at pipe elbows based on far-field eddy currents. Background technique [0002] Pipes are widely used in many industries such as oil and gas, chemical industry, electric power and heating, and pipe elbows are an indispensable part of pipeline piping systems. Most pipe elbows are affected by high temperature, high pressure and complex external environment during work, and the inside of the outer curved surface of the pipe elbow is always eroded by the medium during use, resulting in erosion corrosion and thinning of the pipe wall. In addition, under high temperature and high pressure, the pipe elbow wall is prone to cracks. The above defects are easy to expand rapidly under high pressure, causing cracks in the pipe wall at the pipe elbow, which in turn leads to leakage accidents. The conditi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): G01N27/90
Inventor 徐志远林章鹏李海超谭援强
Owner XIANGTAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap