Corrosion may develop and grow on steel pipes under layers of insulation cladding. Inspection the through these protective is paramount importance. Pulsed eddy current (PEC) a primary non-destructive testing (NDT) technique candidate for this type inspection as it requires no contact with material. To overcome variability in PEC signals due to variations cladding thickness, large measurement se...

High-voltage transmission lines are the main facilities for power transmission, and they mainly composed of aluminum conductor steel-reinforced (ACSR). Over long-term outdoor use, overhead will encounter lightning strikes, chemical pollutant corrosion, deicing, wind vibration, other external forces. This often results in a series potential failures, such as breakage, strands. In order to ensure...

The pulsed eddy current responses to varying material thickness and conductivity are modeled using an electrical circuit ideal transformer non-linear model. The Levenberg-Marquardt algorithm is used to curve fit the experimental signal to the model. The resulting synthetic signal is examined for its ability to preserve experimental signal features such as lift-off point of intersection (LOI), a...

Eddy current testing can be used to interrogate steels but it is hampered by the lift-off distance of sensor. Previously, point intersection (LOI) feature has been found for pulsed eddy (PEC) testing. In this paper, a invariant inductance (LII) proposed multi-frequency (MEC) testing, which merely targets ferromagnetic steels. That is, at certain working frequency, measured signal nearly immune ...

PEC inspection is a multifrequency technique for eddy currents that measures the variation in electromagnetic field caused by induced electrical metal, correlating obtained signal with desired property variation. The speed of execution test and ease interpreting signals are advantageous characteristics this technique, which allows evaluation thickness loss boiler tubes thus increases operationa...

We present recent work on a dual probe system containing electromagnetic acoustic transducers (EMATs) generating and detecting surface ultrasonic waves, and a pulsed eddy current (PEC) probe. This system is able to detect and size surface and near-surface defects in electrically conducting samples by looking at changes in the detected signal for each probe. By combining the information from eac...

For the forecasting of the fatigue life of metallic constructions it is important to understand the mechanism that leads to the failure. Neither, the continuum mechanics nor the micromechanics provide sufficient answers. However, a basic understanding of structural changes on different scaling levels is given by the physical Mesomechanics derived for a medium with local structure. For ferromagn...

Abstract The problem of corrosion in the industrial oil and gas pipes has been one major contributors catastrophic structural failures. Among various types corrosion, under insulation (CUI) known to cause serious problems. Pulsed eddy current (PEC) non-destructive testing shown its effectiveness detecting hidden CUI. Most PEC systems have developed by using an inductive coil as their sensing de...

Pulsed eddy current (PEC) technique provides a means to inspect structures without surface contact. It is particularly useful when the structure's rough or inaccessible, such as insulated pipes in pipeline. Probe parameters of PEC system, especially sensing and excitation coil diameters, can significantly affect system's performance. Thus, detailed analysis these paramount developing system. Cu...