連鋳スラブの熱間渦流探傷
1984 年 70 巻 9 号 p. 1202-1209
詳細
1984 年 70 巻 9 号 p. 1202-1209
Eddy current inspection methods for continuously casted slabs under hot stage have been developed. In order to suppress the signal caused by oscillation marks, several signal processings are discussed. A new signal processing combined with multifrequency eddy current testing and signal pattern analysis can detect fine transverse cracks at the bottom of oscillation mark.
An eddy current testing system with a spot scarfer for the detection of subsurface cracks is operating in Kashima Steel Works of Sumitomo Metals. The scarfing nozzel is used for both smoothing the surface before eddy current inspection and removing cracks by the inspection results.
These methods can detect cracks whose depth is 2mm, and will greatly contribute to the expansion of hot charge rolling process (HCR).
