Hello all, Im an novice here and have a basic understanding of mechanical engineering and related concepts. My question is related to bolt fatigue.
Reference the attached document regarding AN-4 bolt fatigue life related to preload, im wondering how can you quantify this into the real world? for example an AN-4 bolt with no preload at 625 lbs load has 10^6 life (safe life) but how do you define a condition where this bolt would receive 800 or 900 lbs load? the life is no longer 10^6 but is it now 10^3 or 10^2 cycles? and the second part of my question is how does this relate to the real world? Could a bolt receive 625 lbs load for one million times before it would fatigue crack? is this 40 years of flying? 100 years ?
Reference the attached document regarding AN-4 bolt fatigue life related to preload, im wondering how can you quantify this into the real world? for example an AN-4 bolt with no preload at 625 lbs load has 10^6 life (safe life) but how do you define a condition where this bolt would receive 800 or 900 lbs load? the life is no longer 10^6 but is it now 10^3 or 10^2 cycles? and the second part of my question is how does this relate to the real world? Could a bolt receive 625 lbs load for one million times before it would fatigue crack? is this 40 years of flying? 100 years ?