Continuous nondestructive testing device for cable-in-conduit conductor local defects

Abstract

The invention discloses a continuous nondestructive testing device for cable-in-conduit conductor local defects. The continuous nondestructive testing device for the cable-in-conduit conductor local defects is characterized in that a magnetic field detector is a square Hall sensor array formed by front row, back row, upper row and lower row of Hall sensors; a cable-in-conduit conductor sequentially penetrates through a detection inlet at one end of a Dewar, the center of an excitation coil and the center of the square Hall sensor array and penetrates out of a detection outlet at the other endof the Dewar; and the detection inlet side of the cable-in-conduit conductor is connected with a pushing mechanism of the cable-in-conduit conductor. By adopting the continuous nondestructive testingdevice, the local defects of the cable-in-conduit conductor can be continuously and nondestructively detected, and thus reliable experiment data is provided for formulation of a stranded cable and extrusion formation technology of a superconductor cable; and online real-time nondestructive detection can also be performed on the local defects in the preparation process of the cable-in-conduit conductor, so that the performance and the reliability of the cable-in-conduit conductor are improved, and the service life of the cable-in-conduit conductor is prolonged.

Description

technical field [0001] The invention relates to a detection device for a cable conductor in a pipe. Background technique [0002] Large superconducting magnets can provide a strong magnetic field in a large space with almost no power consumption, and have been widely used in high-energy ion accelerators, nuclear fusion, magnetic fluid power generation and other fields. Superconducting magnets are mainly composed of Cable-in-Conduit Conductor (CICC) winding. The cable conductor in the tube is composed of a superconducting cable formed by multi-stage twisting of superconducting strands, a central cooling hole and an outer casing. During the twisting process of each level of the superconducting cable, the superconducting strands may be subjected to different degrees of stress, which will cause local defects to occur, and the performance of this part will degrade (the critical current decreases); During the extrusion molding process, the superconducting strands are also subjec...

AI Technical Summary

Problems solved by technology

The cable conductor in the tube is formed by multi-level twisting of superconducting strands. When the cable conductor in the tube passes through the Hall sensor next to it continuously, the cross section of the closest superconducting part is not the same, but a continuous twist (rotation) ) is non-circular; therefore, the residual magnetic field continuously measured by the Hall sensor is not uniform, but will produce large fluctuations; thus, it will cover up the residual magnetic field changes caused by local defects, and cannot detect the local cable conductor in the tube. defect

Images