Eddy Current Testing - Level I

1.0  Introduction to Eddy Current Testing

• 1.1 Historical and developmental process
• 1.2 Basic physics and controlling principles

2.0  Electromagnetic Theory

• 2.1.1 Generation of eddy currents by means of an AC field
• 2.1.2 Effect of fields created by eddy currents (impedance changes)
• 2.1.3 Effect of change of impedance on instrumentation
• 2.1.4 Properties of eddy current

3.0  Types of Eddy Current Sensing Elements

• 3.1 Probes
• 3.1.1 Types of arrangements (Probe coils, Encircling coils , Inside coils)
• 3.1.2 Modes of operation ( Absolute, Differential, Hybrids )
• 3 1.3 Theory of operation
• 3.1.4 Hall Effect sensors
• 3.1.5Applications ( Measurement of material properties , Flaw detection , Geometrical features)
• 3.1.6 Advantages
• 3.1.7 Limitation
• 3.1.8Factors affecting choice of sensing elements

(Type of part, Type of discontinuities, Speed of testing, Amount of testing, Probable location of discontinuity)

4.0  Selection of Inspection Parameters

(Frequency, Current / voltage, Channel gain, Display sensitivity selections, Standardization, Filtering, Thresholds)

5.0  Readout Mechanisms

• 6.0  Practical Training
• 6.1 Filter effects on reference standards.
• 6.2 Lift – off effects.
• 6.3 Frequency effects.
• 6.4 Rotational & forward speed effects.
• 6.5 Generate a Z-Curve with conductivity standards.