Thanks interesting, in my working life for many years, i worked in fabrication, and repairing in the food manufacturing industry, we would use 316 SS all the time (by law inspectors would check) and several times not often had nut and bolts lock up solid i'm talking about when you first screw the nut on by hand maybe only a few threads in, it would lock up you then had to cut the bolt off and start again, and as luck would have it usually in the most awkward places to get to, as said not often but can happen!