METHOD AND DEVICE FOR CHECKING DETERIORATION OF NUCLEAR REACTOR PRESSURE VESSEL

摘要

PROBLEM TO BE SOLVED: To provide a method and a device for checking the deterioration of a nuclear reactor pressure vessel in which the nuclear reactor pressure vessel is a direct subject to be non-destructively measured. SOLUTION: A first magnetic yoke 201 is closely adhered to the inner wall of one of the nuclear reactor pressure vessels 204 or 205, and a second magnetic yoke 201' is closely adhered to the inner wall of the other nuclear reactor pressure vessel. The magnetic yokes are magnetized to form several closed magnetic circuits in the magnetic yokes and the nuclear reactor pressure vessels. Hysteresis magnetizing properties of the closed magnetic circuits are measured to obtain the distribution of coercive force in the direction of thickness. The distribution of material deterioration in the direction of thickness of the nuclear reactor pressure vessel is checked using the distribution of coercive force. COPYRIGHT: (C)2003,JPO