PURPOSE: To provide a method and device for evaluating the quality of superconducting equipment by detecting AE signals generated during the cooling process of the superconducting equipment and evaluating the generating state of the AE signals.
CONSTITUTION: Superconducting equipment 2 is put in a cryostat 1 and cooled with liquid nitrogen 3. AE sensors 4a, 4b, 4c, and 4d detect AE signals generated during the cooling process of the equipment 2 and an AE evaluating and processing section 6 analyzes and evaluates the AE signals. An acceptance discriminating section 7 discriminates the equipment 2 as unacceptable when the AE signals are generated in excess of a reference value or the generation of the AE signals is concentrated to a specific area. The section 7 identifies the defective location and improves the quality by taking a measure to make conductor movement (wire motion) to hardly occur. When such a method is used, the quality of the equipment 2 can be inspected by cooling only. Therefore, the inspection cost can be remarkably reduced, because the inspection time can be shortened. In addition, since the quality of defective products can be improved, superconducting equipment can be manufactured efficiently.
SATO KAZUYA
TOMINAKA TOSHIJI
SATO YOSHIYUKI
HITACHI ENG SERVICE