A possibility of MFL method for condition monitoring of wall thinning

This paper describes an applicability of magnetic flux leakage (MFL) method for a nondestructive evaluation of wall thinning in nuclear power plants. Since MFL method has already been applied to other industry field, this method should be an effective tool in nuclear power plants. Here, in order to investigate a possibility of MFL method for condition monitoring of wall thinning, steels with slit were prepared and distribution of leakage magnetic flux was evaluated systematically using magnetic probe and magnetic field sensor when a position between a probe and a slit changed. Using the difference between the results for specimen with slit and without slit, estimation of slit size and slit position can be possible. (author)