Integral MFL (Magnetic Flux Leakage) and eddy current array sensor for detecting copper-coated/aluminum-coated steel shaft type structure

Abstract

The invention discloses an integral MFL (Magnetic Flux Leakage) and eddy current array sensor for detecting a copper-coated / aluminum-coated steel shaft type structure, and belongs to the field of ENDT (Electromagnetic Non-destructive Testing). The integral MFL and eddy current array sensor comprises annular permanent magnets, array type eddy current sensor units, wire clamping discs, a cylindrical shell type shielding layer, an MFL induction coil, a supporting frame and a protection shell, wherein the two annular permanent magnets are arranged on two ends of the supporting frame in a sleeving way and are used for providing an axial magnetostatic field to magnetize a detected component; the MFL induction coil is used for detecting a leakage magnetic field which is formed on the surface of the detected component; the shielding layer is used for detecting sensitive areas on the array type eddy current sensor units to form a near-zero magnetic field; the eddy current sensor units are annularly and uniformly arranged along the detected component and are used for detecting the variation of an eddy current field in a surface defect area; the copper-coated / aluminum-coated steel detected components of the array type eddy current sensor units and the MFL induction coil are connected to a sensor electrical interface after being led out through the wire clamping discs which are arranged at two sides of the supporting frame. According to the integral MFL and eddy current array sensor for detecting the copper-coated / aluminum-coated steel shaft type structure, disclosed by the invention, dual functions of MFL testing and eddy current testing are obtained, and total-structure defect NDT (Non-destructive Testing) can be carried out on an aluminum-coated steel stranded wire, a copper-coated steel ground rod and the like.

Description

technical field [0001] The invention is an integrated magnetic flux leakage and eddy current array sensor for detecting copper or aluminum-clad steel shaft structures, belongs to the technical field of electromagnetic nondestructive testing, and can be used for nondestructive testing of structures such as aluminum-clad steel strand structures and copper-clad steel ground rods. Background technique [0002] The high-voltage transmission line belongs to the structure of aluminum-clad steel strands, the core of which is made of twisted multi-strand steel strands, surrounded by multi-layer aluminum strands; copper-clad steel is widely used in grounding projects, and the inner steel core is made of high-quality The outer layer is made of low-carbon steel, and the outer layer is coated with high-purity copper on the steel core by electroplating or cladding process. The thickness of the copper layer is determined by the actual required resistance or conductivity. Aluminum-clad stee...

AI Technical Summary

Problems solved by technology

The present invention aims to provide a magnetic flux leakage and eddy current integrated array sensor for detecting copper or aluminum-clad steel shaft structures, and simultaneously solve the problem of non-destructive testing of the surface layer and steel core of copper or aluminum-clad steel structures

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