1. You are asked, as a consultant, to determine a procedure for finding a “best estimate” for the design stress to be used in designing the helical-coil springs for a new off-the-road vehicle. The only known information is:
( 1. ) The spring material is a ductile high-strength ferrous alloy with known ultimate strength, , and known yield strength, .
( 2.) Spring deflection during field operation is estimated to range from a maximum of to a minimum of .
( 3.) Very long life is desired. Based on the known information, write a concise step-by-step procedure for determining a “best estimate” value for the design stress.
