| MadSci Network: Engineering |
EP You are correct. All machine elements are subject to fatigue, including bolts although with bolts the subject does get a little muddy. As you are aware from your machine design classes, the maximum load that a properly sized and installed bolt will ever be subjected to is that of installation. The magnitude of any stresses due to a cyclic load must kept to a small fraction of the preload. Doing so will make the likelyhood of a fatigue failure very small. If a bolt is properly sized, but improperly installed (ie, the bolt is not tighted to the proper torque level) failure is very likely. I hope this is helpful. Greg
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