Portable device for thermal nondestructive testing of hidden corrosion in metallic shells by using a LED heat source

Thermal nondestructive testing (NDT) is a promising technique for detecting hidden corrosion in metallic shells, such as above-ground tanks, pipes, containers, etc., due to its high productivity and illustrativeness. However, the use of powerful halogen lamps in practical applications is questionable because of reflected radiation and safety requirements. In this paper, a portable thermal NDT device using a LED heater is described. Such heaters operate at wavelengths which are beyond of the spectral band of contemporary infrared imagers. Also, they can use a battery as a power supply thus meeting in-field requirements, for example, in the petrochemical industry. Depending on defect size and material loss, the developed portable thermal NDT device can detect corrosion in steel shells with thickness up to 8 mm