Eddy Current Testing (ET)
Eddy Current Testing (ET) is used mainly for inspection of aerospace structures and coated components, for the detection of both surface and near surface discontinuities. ET can be used for the inspection of tubes, forgings and welds.
In this method a current is induced when a magnetic field cuts through a metal. An “Eddy Current” is generated when the magnetic field cuts through a metal sample that is not connected to a circuit. This Eddy Current produces a flow pattern which is disturbed by the existence of any discontinuities from the surface up to a shallow depth of penetration in the component that is inspected.
The Eddy Current method can be only applied to electrically conductive materials, does not require direct contact with the component that is inspected, and produces results of high sensitivity and repeatability.
Course Content
- History of ET
- Electromagnetism Theory
- Terms and Definition
- Principles of Eddy Currents
- Analysis of Signals
- Sensitivity of ET
- Equipment and Inspection Methods
- Advantages/Disadvantages
- Preparation for Testing
- Carrying out the Test
- Post Test Procedures
- Safety Precautions
- Test Procedures
- Detectability of Defects
- Interpretation and Reporting
- Standards and Specifications
- Basic production of weld and wrought products
- Extensive practical element
Responsibilities of an Eddy Current Testing Level 2 NDT professional:
- 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
