How often do you grab a wrench and tighten a bolt or “over tighten” a bolt with little or no thought about what the intended job of the bolt you are tightening is? I know most of us are guilty! We are under the assumption if tight is good then tighter is better! So we grab a wrench and pull that bolt down nice and tight, completely unaware of the fact we may have overstressed the bolt and it is now only capable of holding a portion of its designed load! All bolts have a design load or said another way they are manufactured with a maximum stress load in their design.
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Nuts and Bolts June 2013