The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 16, 1987
Filed:
Sep. 28, 1983
Takahide Sakamoto, Hyogo, JP;
Tatsuo Hiroshima, Hyogo, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
A method and apparatus for measuring a liner thickness of a zirconium liner provided at the inner surface of a zirconium alloy tube, the principle of measurement of which is to insert coils into the tube to generate an eddy current, detect the impedance component in the direction perpendicular to the direction of coil impedance change caused by the lift-off variation between the coils and the inner surface of tube, and obtain the liner thickness on the basis of the impedance component. In a case where the lift-off variation is larger, the impedance component in the direction of coil impedance change caused by the lift-off variation is detected, so that the component is used to correct the impedance component perpendicular to the same, thereby obtaining the liner thickness in accordance with the corrected values.