1.A helical-coil spring is to be wound using wire made from a proprietary ferrous alloy for which , , , , , and . It is desired to use the spring in a cyclic loading situation where the axial load on the spring during each cycle ranges from 450-N tension to 450-N compression. The spring deflection at maximum load must be 50 mm. A spring with 18 active coils is being proposed for the application.
a. Compute the existing safety factor for this spring based on an infinite-life design criterion. Comment on the results.
b. If the spring is wound so that when it is unloaded the space between coils is the same as the wire diameter, would you expect buckling to be a problem? (Support your answer with appropriate calculations.)
c. Approximately what maximum operating frequency should be specified for this mechanism?
