Thermography is the simplest of all thermal inspection techniques and involves using an infrared camera to look for abnormally hot or cold areas on a component operating under normal conditions.
For example, areas of corrosion thinning on plant carrying hot gas or liquid will show up as unusually hot areas on am infrared thermal image. Most modern thermal cameras are able to detect temperature differences of less than 0.25°C and enable thermal images to be recorded on video or computer disk for future analysis.
Thermography is a useful technique for the detection of corrosion/erosion damage in plant operating at elevated temperatures. In addition, it can be used to check for fouling or internal plugging of piping systems and to check the quality of refractory linings. It can also be used for leak detection, composition changes, disbonds in laminates and others.
Infrared Thermography Inspection is a remote technique that can be applied to most areas of plant, but which is particularly suited to plant operating at elevated temperatures. However, it is a surface technique and it cannot be used to look through thick layers of lagging for defects in the underlying structure.