Question; We have a number of pressure vessels onsite. These are are compressed air tanks and we would like to test them for cracks, damage, sludge and non visible rust etc.
None of the vessels have cladding and all are made of mild steel. There are some indoor and some outside so the ambient temperature is normal daytime temperatures. The compressed air inside various a bit but is close to ambient. What can we do with thermography?
Answer; Thermography is not the best NDT technique to employ for what you are trying to look at. There is little or no temperature difference, so there will be little or no heat flow. You will therefore be able to detect little or nothing. You might be able to detect a buildup of sludge in the tank, and I would not consider this too difficult. Cracks really need another NDT method, sure you might have some luck in some circumstances, but in your conditions, I think it is unlikely. Rust may be detectable, but I think that it is likely that it will be visible anyway. My best advice, stick to looking for the sludge, leave everything else for other methodologies.