PURPOSE: To detect a flaw generated at the seam part of the title electric welded tube with a good S/N and high accuracy by performing flaw detection operation while performing follow-up control automatically so that a probe type coil is arranged at the center position of a high-temperature area.
CONSTITUTION: A center position detecting device 1 for the high-temperature area outputs an electric signal indicating the deviation quantity between the center position of the high-temperature area and a reference position. A servo amplifier 5 is applied with the analog output generated by the detector and the output of a potentiometer 4 which operates associatively with a follow-up mechanism 2 having a through-hole 7. A servo motor 3 driven with the output of this servo amplifier 5 drives the follow-up mechanism 2 and performs control so that the reference position is aligned with the center of the high-temperature area. Then the probe type coil 6 provided at the reference position of the follow-up mechanism 2 is moved relatively to makes a flaw detecting scan on the seam part 41 and thus local variation is detected to know the presence of a defect. Further, a marking device marks a part nearby the position where the defect is present.
UENO AKIO
OKUHARA SEIICHI
UENO AKIO
OKUHARA SEIICHI
| JPS5168447A | 1976-06-14 | |||
| JPS52126277A | 1977-10-22 | |||
| JPS61107148A | 1986-05-26 |