Corrosion Under Insulation using QWHE sensors
The ability to routinely observe and monitor Corrosion Under Insulation is of great importance to assist the industry in keeping ageing assets operational and safe and ensure the maximum extraction from diminishing production capability. The ability to inspect without the need for plant shutdown provides increased throughput and therefore revenue.
The AHS core magneto-imaging technology is applicable to any situation that requires real time, low skill/intervention defect detection and identification. This is a flexible core technology for a variety of application specific NDE implementations such as screening for weld defects, fissures, cracks, corrosion and sub-surface defects.
The operational advantage is that the system is inherently non-contact, and capable of generating multi-dimensional images which gives contextual information on the nature of a CUI defect such as size, geometry and depth. It can be used as a triage tool to alert the presence of defects within a specific size range, through to determination of the detailed nature of a particular defect. The direct operational impact will be a significant reduction in the false positive detections, and hence an increase in the bulk screening rate of fixed installations, without removal of insulating materials.
The QWHE-CUI technique works on a completely different principle to traditional pulsed eddy current and is capable of imaging corrosion without the need for calibration as a first pass triage technique.
This new technique provides a highly linear relationship between signal voltage, wall thickness loss and the inverse square of insulation thickness. As such technique provides a much simpler and intuitive process for the determination and evaluation of wall thickness loss mapping.