GB1242747A - Eddy current testing - Google Patents

Eddy current testing

Info

Publication number
GB1242747A
GB1242747A GB3827768A GB3827768A GB1242747A GB 1242747 A GB1242747 A GB 1242747A GB 3827768 A GB3827768 A GB 3827768A GB 3827768 A GB3827768 A GB 3827768A GB 1242747 A GB1242747 A GB 1242747A
Authority
GB
United Kingdom
Prior art keywords
carrier frequency
coil
test
amplitude modulation
capacitors
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.)
Expired
Application number
GB3827768A
Inventor
Victor John George Upton
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
C N S INSTR Ltd
Original Assignee
C N S INSTR Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by C N S INSTR Ltd filed Critical C N S INSTR Ltd
Priority to GB3827768A priority Critical patent/GB1242747A/en
Publication of GB1242747A publication Critical patent/GB1242747A/en
Expired legal-status Critical Current

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

1,242,747. Eddy current flaw detectors. C. N. S. INSTRUMENTS Ltd. Aug.9, 1968, No.38277/68. Heading G1N. Flaws are detected by applying a carrier frequency current to a test coil, subjecting the material to be tested to the magnetic field of the coil, arranging that changes in the phase angle of the coil give rise to amplitude modulation of the carrier frequency current and detecting the amplitude modulation by a rectifier provided with a by-pass capacitor for the carrier frequency. Two test coils may be provided; the second co-operating with a standard or with an adjacent area of the test material. As shown in Fig.1, two test coils 1, 2 are connected in parallel with capacitors to form respective tuned circuits, the carrier frequency generated at 5 coinciding with the steepest part of the resonance curve. Alternatively, series tuned circuits may be used. Respective rectifiers 13, 14 and by-pass capacitors 8, 9 are provided. As shown in Fig. 3, two test coils 1, 2 are inductively coupled to a primary coil 18 and are fed with a quadrature signal via line 19.
GB3827768A 1968-08-09 1968-08-09 Eddy current testing Expired GB1242747A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB3827768A GB1242747A (en) 1968-08-09 1968-08-09 Eddy current testing

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3827768A GB1242747A (en) 1968-08-09 1968-08-09 Eddy current testing

Publications (1)

Publication Number Publication Date
GB1242747A true GB1242747A (en) 1971-08-11

Family

ID=10402404

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3827768A Expired GB1242747A (en) 1968-08-09 1968-08-09 Eddy current testing

Country Status (1)

Country Link
GB (1) GB1242747A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4109201A (en) * 1976-01-22 1978-08-22 Commissariat A L'energie Atomique Measuring bridge for an inspection or checking device by means of eddy currents
GB2187558A (en) * 1986-03-04 1987-09-09 Atomic Energy Authority Uk Determining the magnetic flux density within a specimen during magnetic particle inspection techniques
CN112485326A (en) * 2020-12-09 2021-03-12 中国石油大学(华东) Dual-mode detection system utilizing planar spiral coil capacitance effect

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4109201A (en) * 1976-01-22 1978-08-22 Commissariat A L'energie Atomique Measuring bridge for an inspection or checking device by means of eddy currents
GB2187558A (en) * 1986-03-04 1987-09-09 Atomic Energy Authority Uk Determining the magnetic flux density within a specimen during magnetic particle inspection techniques
GB2187558B (en) * 1986-03-04 1990-07-04 Atomic Energy Authority Uk A method and apparatus for determining the magnetic flux density within a specimen in magnetic particle inspection techniques
CN112485326A (en) * 2020-12-09 2021-03-12 中国石油大学(华东) Dual-mode detection system utilizing planar spiral coil capacitance effect
CN112485326B (en) * 2020-12-09 2024-01-26 中国石油大学(华东) Dual-mode detection system utilizing planar spiral coil capacitance effect

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