JPS5793251A - Device for detecting flaw by eddy current - Google Patents
Device for detecting flaw by eddy currentInfo
- Publication number
- JPS5793251A JPS5793251A JP55169929A JP16992980A JPS5793251A JP S5793251 A JPS5793251 A JP S5793251A JP 55169929 A JP55169929 A JP 55169929A JP 16992980 A JP16992980 A JP 16992980A JP S5793251 A JPS5793251 A JP S5793251A
- Authority
- JP
- Japan
- Prior art keywords
- output
- phase
- analog
- signal
- sent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/90—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents
- G01N27/9046—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents by analysing electrical signals
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
PURPOSE:To make it possible to measure the depth of a minute defect, by dif- ferentiating a vector signal generated when a pair of detecting coils pass the center of the defect and inputting output thereof to a specified computing circuit. CONSTITUTION:The detecting coils 3a and 3b are arranged on the adjacent symmetrical positions with respect to a sweeping axis, and constitute a bridge to- gether with resistors 4a and 4b. The unbalanced output from the bridge circuit is sent to phase detectors 6 and 6b through an amplifier 6 and phase-detected, with the output signals from a phase shifter and a 90 deg. phase shifter circuit 8 as references. Output signals X and Y from the phase detectors 6 and 6b are differentiated by differentiating devices 11a and 11b, and signal x1 and y1 are obtained. Said signal y1 is sent to a halfwave rectifier 16 through an analog gate 13 which is closed when the output of x1 is generated. The positive part y2 of y1 is taken out and the product of y2 and coefficient K is computed by a multiplication coefficient setting device 18. Thereafter, the computation of the expression of relation (I) is processed in an analog subtractor 19 and an analog divider 20, and an output Vo is obtained through the halfwave rectifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55169929A JPS5793251A (en) | 1980-12-02 | 1980-12-02 | Device for detecting flaw by eddy current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55169929A JPS5793251A (en) | 1980-12-02 | 1980-12-02 | Device for detecting flaw by eddy current |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5793251A true JPS5793251A (en) | 1982-06-10 |
| JPS6241342B2 JPS6241342B2 (en) | 1987-09-02 |
Family
ID=15895547
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55169929A Granted JPS5793251A (en) | 1980-12-02 | 1980-12-02 | Device for detecting flaw by eddy current |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5793251A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59166858A (en) * | 1983-03-14 | 1984-09-20 | Tokushu Toryo Kk | Eddy current flaw detecting method of pipe using interpolating coil |
| JPS59166859A (en) * | 1983-03-14 | 1984-09-20 | Tokushu Toryo Kk | Eddy current flaw detector for pipe provided with interpolating coil |
| JP2006208312A (en) * | 2005-01-31 | 2006-08-10 | Jfe Steel Kk | Method and device for measuring internal defect |
| JP2011127922A (en) * | 2009-12-15 | 2011-06-30 | Sumitomo Metal Ind Ltd | Method of eddy current flaw inspection, and gap forming member used for the same |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01185166A (en) * | 1988-01-13 | 1989-07-24 | Tokyo Electric Co Ltd | Inverter apparatus |
-
1980
- 1980-12-02 JP JP55169929A patent/JPS5793251A/en active Granted
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59166858A (en) * | 1983-03-14 | 1984-09-20 | Tokushu Toryo Kk | Eddy current flaw detecting method of pipe using interpolating coil |
| JPS59166859A (en) * | 1983-03-14 | 1984-09-20 | Tokushu Toryo Kk | Eddy current flaw detector for pipe provided with interpolating coil |
| JPH0378579B2 (en) * | 1983-03-14 | 1991-12-16 | Marktec Corp | |
| JP2006208312A (en) * | 2005-01-31 | 2006-08-10 | Jfe Steel Kk | Method and device for measuring internal defect |
| JP2011127922A (en) * | 2009-12-15 | 2011-06-30 | Sumitomo Metal Ind Ltd | Method of eddy current flaw inspection, and gap forming member used for the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6241342B2 (en) | 1987-09-02 |
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