Design of a handheld system for detection of Corrosion Under Insulation using Quantum Well Hall Effect Sensors

Corrosion Under Insulation (CUI) is a form of damage that can be difficult to detect. The insulation used can both hide the damaged pipes and create a large standoff distance between the flaw and any measuring device. Magnetic Flux Leakage (MFL) systems utilising Quantum Well Hall Effect (QWHE) sensors have been demonstrated as an effective method for imaging CUI. As pipes, in situ, cannot be easily removed for measurements, the system being designed here is intended to operate as a handheld system, capable of measuring pipes of arbitrary geometries. The handheld system is built around a microcontroller, signal measurement board, and coil. The coil is used for generating a magnetic field which is applied to a sample. The return field is then detected by the QWHE sensors and measured by a microcontroller. This magnetic signal is then processed in real time and displayed on a screen as line data. The line data corresponds to the relative amplitude of magnetic permeability in the sample being scanned, which will sharply drop when an area of corrosion is encountered. A rendering of the system is shown below in Figure 1.