Invention Grant
- Patent Title: Eddy current testing method, steel pipe or tube tested by the eddy current testing method, and eddy current testing apparatus for carrying out the eddy current testing method
- Patent Title (中): 涡流测试方法，通过涡流测试方法测试的钢管或管，以及用于进行涡流测试方法的涡流测试装置
-
Application No.: US12530763Application Date: 2008-03-11
-
Publication No.: US08269488B2Publication Date: 2012-09-18
- Inventor: Shigetoshi Hyodo , Satoshi Kureishi
- Applicant: Shigetoshi Hyodo , Satoshi Kureishi
- Applicant Address: JP Osaka-shi
- Assignee: Sumitomo Metal Industries, Ltd.
- Current Assignee: Sumitomo Metal Industries, Ltd.
- Current Assignee Address: JP Osaka-shi
- Agency: Marshall, Gerstein & Borun LLP
- Priority: JP2007-064843 20070314
- International Application: PCT/JP2008/054334 WO 20080311
- International Announcement: WO2008/126553 WO 20081023
- Main IPC: G01N27/32
- IPC: G01N27/32
Abstract:
It is an object of the present invention to provide an eddy current testing method capable of securely detecting a high hardness part locally occurring in a metal material having magnetism, and capable of securely checking whether the high hardness part has been removed after execution of a repairing treatment for removing the high hardness part.In the eddy current testing method according to the present invention, a frequency of the AC current for energizing the differential coil 1 is set so that a phase difference between a magnetism variation signal of the metal material P and a liftoff signal detected by the differential coil is equal to or larger than 135°, and a local high hardness part occurring in the metal material is detected based on an amplitude and a phase of a detection signal outputted from the differential coil.
Public/Granted literature
Information query
