EXTENDE

EDDY CURRENT MODULE

ET simulation tools allow to predict the electromagnetic field induced in the component, to compute the normalized impedance diagram of an ET sensor, and to simulate the defect response.

SENSORS

The range of ET sensors available in CIVA library includes:

• Axial coil, encircling coil, surface riding or sectorial coil, in tubular configurations
• Surface riding coil on planar configurations
• Air-core or ferrite-core sensors having cylindrical core, C-shape or E-shape cap

ACQUISITION

The simulated inspection can involve several sensors that can operate in differential or absolute mode, with separate or common Transmit/Receive functions.
This is possible to manage several channels and several frequencies in one shot.

WORKPIECE

CIVA allows to model the inspection in components of different geometries:

• Tube
• Homogeneous planar workpiece
• Multilayer planar workpiece
• Riveted structure and bore

Material properties are defined by one conductivity and one permeability.
It is possible to simulate ferromagnetic tubes control, with the Remote Field Eddy Current method (RFEC).

FLAW

One flaw can be defined in the workpiece.
Various types of defects are available:

• Transversal or longitudinal notch in cylinders
• Inner and outer grooves in cylinders
• Flat Bottomed Hole in any component
• Parallelepipedic crack, in planar or riveted workpiece
• Semi-elliptical slot in planar geometries

RESULTS

Field and Impedance in free-flaw 2D configuration

CIVA ET proposes a fast analytical field computation tool in 2D homogeneous configurations. This allows to visualize with color-shaded charts eddy current distribution.
Combined with an impedance diagram calculation for a set of different frequencies, this tool allow to select the optimum operation frequency, considering both impedance and skin depth values.
In cylindrical geometries, you can plot the field for axial coils (encircling or internal).

3D Defect response

The simulation of defect response in planar workpieces can be realized for one or several sensors with or without ferrite core. The plate can be defined with one or several materials.
The computation of defect response in tubes, possibly ferromagnetic (RFEC), can be realized with surface riding probes, axial coils (internal, external, centered of off-centered) or sectorial coils.
The modelling can also allow to study lift-off or probe orientation variations.

ANALYSIS TOOLS

In the CIVA post-processor, you can visualize impedance variations with C-scan views or in the impedance plane.
This environment allows to quickly and simply access to the most interesting quantities: Amplitude, Phase, Lissajous curve, X and Y channels.
Other built-in processing tools are available in order to help the analysis of the ET signal: Calibration, Balancing, Filtering, Frequency mixing.