Rotating magnetic field eddy current detection probe

Abstract

The invention discloses a rotating magnetic field eddy current detection probe. The eddy current detection probe consists of two eddy current probe arrays, wherein each eddy current probe array is circumferentially arranged; the first eddy current probe array comprise a plurality of excitation coils and a plurality of detection coils; all the excitation coils are divided into three groups; each unit of the second eddy current probe array adopts a cuboid structure; two groups of excitation coils are wound on the outer surface of the cuboid and perpendicular to each other; the two eddy current probe arrays are connected with each other through a bendable elastic connecting device; the detection coils are positioned at the bottoms of the excitation coils; if a rotating magnetic field encounters a defect in an object to be detected, the movement of the magnetic field is changed, and the changed magnetic field can be detected by the detection coils. According to the invention, multiphase excitation is provided for the excitation coils of the eddy current probe arrays to generate the rotating magnetic field, so as to improve sensitivity for detecting defects in different directions and achieves the purposes of increasing scanning speed and improving scanning accuracy under the condition of no mechanical movement.

Description

technical field [0001] The invention relates to a nondestructive testing probe, in particular to a rotating magnetic field eddy current testing probe for detecting surface defects of conductor materials. Background technique [0002] With the improvement of safety awareness and requirements, there is an increasing demand for the integrity detection of metal parts of production equipment. Eddy current testing is a widely used non-destructive testing technique, mainly used to detect cracks or defects on the surface of conductive materials. The working principle follows the principle of electromagnetic induction. When the excitation coil with alternating current is close to the conductor material, an alternating magnetic field will be generated in the conductor material, which is called a primary magnetic field. At the same time, the alternating magnetic field induces eddy current on the conductor surface. Eddy currents in conductors also generate a magnetic field, called a se...

AI Technical Summary

Problems solved by technology

However, with traditional probes, since the eddy current induced by the probe does not easily penetrate into the conductor, it is difficult to determine important information such as crack size, location, depth and width.

General probes are only suitable for detecting crack defects in a certain direction of the pipeline, and it is time-consuming and labor-intensive

In actual situations, cracks on the inner surface of pipelines often appear in multiple directions. If the number, direction and shape of cracks cannot be accurately judged, serious safety accidents may result

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