Abstract:

          We reduce the blind ends of steel tubes in eddy current fault detection by the automatic control over the gain of a preamplifier and performance improvement of a bandpass filter for the characteristic of strong signal generated at the end of a steel tube. We can detect the steel pit at the 103 mm away from one end of a steel tube of diameter 168 mm and thickness 6 mm.

Key words: blind end, through type coil round, eddy current fault detection