TRACK: Sustainability/Reliability
Above ground storage tanks are used to store various fluids and chemicals across many industries. The structural integrity of these tanks must be regularly assured, but these inspection operations are hazardous due to the chemicals themselves as well as the requirement to operate within confined spaces. The accepted practice for inspection of these tanks, in particular the tank bottoms, requires removing the tank from service, emptying the tank, and interior entry for direct inspection of the structure. An inspection from outside the tank would have significant cost and time benefits and well as a large reduction in the risks faced by the inspection personnel. Segmented Magnetostrictive Transducer guided wave probes are being developed for this purpose. The inspection process is for a probe is sequentially coupled to the chime (skirt) at multiple locations around the tank bottom. Data is acquired using full matrix capture (FMC) principles and the acquired waveforms are analyzed using the total focusing method (TFM) to image the tank bottom condition. This paper presents the detection capability of this new method in the area near the tank shell and throughout the tank bottom are discussed. Results shown are from data taken on both purpose-built mockups and from field trials.