Home - Education Resources - NDT Course Material - EC Testing
 

-
Eddy Current Testing

Introduction
Basic Principles
History of ET
Present State of ET

The Physics
Properties of Electricity
Current Flow & Ohm's Law
Induction & Inductance
Self Inductance
Mutual Inductance
Circuits & Phase
Impedance
Depth & Current Density
Phase Lag

Instrumentation
Eddy Current Instruments
Resonant Circuits
Bridges
Impedance Plane
Display - Analog Meter

Probes (Coils)
Probes - Mode of Operation
Probes - Configuration
Probes - Shielding
Coil Design
Impedance Matching

Procedures Issues
Reference Standards
Signal Filtering

Applications
Surface Breaking Cracks
SBC using Sliding Probes
Tube Inspection
Conductivity
Heat Treat Verification
Thickness of Thin Mat'ls
Thickness of Coatings

Advanced Techniques
Scanning
Multi-Frequency Tech.
Swept Frequency Tech.
Pulsed ET Tech.
Background Pulsed ET

Remote Field Tech.

Quizzes

Formulae& Tables
EC Standards & Methods
EC Material Properties
-

EC Standards and Methods

STANDARDS

British Standards (BS) and American Standards (ASTM) relating to magnetic flux leakage and eddy current methods of testing are given below. National standards are currently being harmonized across the whole of Europe, and British Standards are no exception. Harmonized standards will eventually be identified by the initials BS EN; for example, BS 5411 has been revised and is now known as BS EN 2360. Harmonization is unlikely to be completed before 2001. The year of updating a British Standard is given in brackets. ASTM standards are published annually and updated when necessary.

FLUX LEAKAGE METHODS (INCLUDING MAGNETIC PARTICLE INSPECTION)

British Standards (BS)

BS 6072:1981 (1986) Magnetic particle flaw detection
BS 4489:1984 Black light measurement
BS 5044:1973 (1987) Contrast aid paints
BS 5138:1974 (1988) Forged and stamped crankshafts
BS 3683 (part 2):1985 Glossary
BS 4069:1982 Inks and powders

American Society for Testing and Materials (ASTM)

ASTM E 709 Magnetic particle inspection practice
ASTM E 125 Indications in ferrous castings
ASTM E 1316 Definition of terms
ASTM E 570 Flux leakage examination of ferromagnetic steel tubular products

EDDY CURRENT METHODS

British Standards (BS)

BS 3683 (part 5):1965 (1989) Eddy current flaw detection glossary
BS 3889 (part 2A): 1986 (1991) Automatic eddy current testing of wrought steel tubes
BS 3889 (part 213): 1966 (1987) Eddy current testing of nonferrous tubes
BS 5411 (part 3):1984 Eddy current methods for measurement of coating thickness of nonconductive coatings on nonmagnetic base material. Withdrawn: now known as BS EN 2360 (1995).

American Society for Testing and Materials (ASTM)

ASTM A 450/A450M General requirements for carbon, ferritic alloys and austenitic alloy steel tubes
ASTM B 244 Method for measurement of thickness of anodic coatings of aluminum and other nonconductive coatings on nonmagnetic base materials with eddy current instruments
ASTM B 659 Recommended practice for measurement of thickness of metallic coatings on nonmetallic substrates
ASTM E 215 Standardizing equipment for electromagnetic testing of seamless aluminum alloy tube
ASTM E 243 Electromagnetic (eddy current) testing of seamless copper and copper alloy tubes
ASTM E 309 Eddy current examination of steel tubular products using magnetic saturation
ASTM E 376 Measuring coating thickness by magnetic field or eddy current (electromagnetic) test methods
ASTM E 426 Electromagnetic (eddy current) testing of seamless and welded tubular products austenitic stainless steel and similar alloys
ASTM E 566 Electromagnetic (eddy current) sorting of ferrous metals
ASTM E 571 Electromagnetic (eddy current) examination of nickel and nickel alloy tubular products
ASTM E 690 In-situ electromagnetic (eddy current) examination of nonmagnetic heat-exchanger tubes
ASTM E 703 Electromagnetic (eddy current) sorting of nonferrous metals
ASTM E 1004 Electromagnetic (eddy current) measurements of electrical conductivity
ASTM E 1033 Electromagnetic (eddy current) examination of type F continuously welded (CW) ferromagnetic pipe and tubing above the Curie temperature
ASTM E 1316 Definition of terms relating to electromagnetic testing
ASTM G 46 Recommended practice for examination and evaluation of pitting corrosion