Question

The lever below is constructed of AISI 1050 cold-drawn steel. It is assumed that bar "DC" is strong enough and hence not part of the problem. The force "F" fluctuates between 50 and 250 lbf. Calculate the factor of safety against yielding and fatigue for a desired reliability of 99.9%. If finite life is predicted, estimate the number of cycles to failure. Use the Gerber Fatigue Failure Theory.

A 12 in 4-in D in R. C 2 in 1-in D 15 in -in D

Answer 1

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