This is the first part in a series of articles discussing non-rotational loosening of threaded fasteners. One feature of nuts and bolts is that they allow complex assemblies to be built and dismantled, as necessary. Under certain conditions, a nut or a bolt can come loose with obvious undesirable consequences. Self-loosening is when the nut, or bolt, rotates under the action of applied forces.(…)
via Non-rotational loosening of threaded fasteners | Fastener + Fixing Technology.