Eddy Current Testing
What is Eddy Current Testing?
Eddy Current Testing is one of the popular and most frequently used Electromagnetic Testing technique. Eddy current testing is a nondestructive test that create an alternating Magnetic field using a wide variety of probes. Any discontinuities hindering the flow of Eddy current will be studied and reported. Amplitude and Phase of the Eddy current are interpreted to analyze the size, shape, location, and severity of the discontinuity. Eddy current is widely used in various sectors like Automobile, Aerospace, oil and gas, ship building etc.
What are the responsibilities of an individual who is certified to Eddy Current Level 2?
An individual certified to Eddy Current Level 2 has demonstrated competence to perform NDT according to Penetrant Testing procedures. Within the scope of the competence defined on the certificate, Level 2 personnel may be authorised by the employer to:
- Select the Eddy Current technique for the test method to be used;
- Define the limitations of application of the testing method;
- Translate NDT codes, standards, specifications and procedures into NDT instructions adapted to the actual working conditions;
- Set up and verify equipment settings;
- Perform and supervise tests;
- Interpret and evaluate results according to applicable standards, codes, specifications or procedures;
- Prepare Eddy Current written instructions
- Carry out and supervise all tasks at or below level 2;
- Provide guidance for personnel at or below level 2, and
- Report the results of Eddy Current test
TRAINING
80 hrs of ECT Level II training covers the following:
Eddy Current Testing Level II training topical outline
General Theory
- Brief history of testing
- Basic principles of testing
- Generation of eddy currents by means of an ac field
- Effect of fields created by eddy currents
- Effect of change of impedance on instrumentation
- Terminology and units
- Principles of magnetisation.
- Magnetisation
- Electromagnetism theory
- Flux leakage theory and principle
- Readout mechanism
- Types of eddy current sensing elements
- Types of flux leakage sensing elements
- Review of electromagnetic theory
- Factors that affect coil impedance
- Factors that affect flux leakage fields
- Signal-to-noise ratio
- Selection of test frequency
- Selection of method of magnetisation for flux
- Leakage testing
- Coupling
- Field strength and its selection
- Field orientation for flux leakage testing
- Instrument design consideration
- Safety as applicable to eddy current testing and electrical safety
Specific Theory
Application of the method to the specific requirements of the company, in particular making reference to those codes, specifications and procedures used by the company, including the relevant control checks.