To directly compare the threat from wear fatigue to bending fatigue in a bevel gear design, how should the contact safety factor SH be compared to the bending safety factor SF?
Explanation
Because contact stress (pitting) is related to the square root of the transmitted load, while bending stress is linearly related to the load, their safety factors are not directly comparable. To make a valid comparison of which failure mode is more critical, the contact safety factor SH must be squared (or the square root taken, depending on the definition) to be on the same basis as the bending safety factor SF.
Other questions
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