A compression spring needed for a machine operation has to fit within a 1-in. diameter hole. To allow for some clearance, the outside diameter of the spring should not be larger than 0.9 in. To ensure a reasonable coil, use a spring index of 9. The spring will be repeatedly cycled from its free length of 3 in. to a length of 2 in. The solid length of the spring is 1 in. The spring should have squared ends and is to be made of music wire. (a) Determine a suitable wire diameter. (b) Determine a suitable number of coils. (c) Determine the spring rate. (d) Calculate the maximum shear stress the spring will experience during fatigue cycling. (e) Show on a stress vs. time plot how the fatigue cycling on the spring will occur. (f) If the spring is unpeened, what will be the shear endurance limit of the spring material in completely reversed cycling? (g) Can the spring survive a million fatigue cycles? Show by calculation.

A compression spring needed for a machine operation has to fit within a 1-in. diameter hole. To allow for some clearance, the outside diameter of the spring should not be larger than 0.9 in. To ensure a reasonable coil, use a spring index of 9. The spring will be repeatedly cycled from its free length of 3 in. to a length of 2 in. The solid length of the spring is 1 in. The spring should have squared ends and is to be made of music wire. (a) Determine a suitable wire diameter. (b) Determine a suitable number of coils. (c) Determine the spring rate. (d) Calculate the maximum shear stress the spring will experience during fatigue cycling. (e) Show on a stress vs. time plot how the fatigue cycling on the spring will occur. (f) If the spring is unpeened, what will be the shear endurance limit of the spring material in completely reversed cycling? (g) Can the spring survive a million fatigue cycles? Show by calculation.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.2.11P: A small lab scale has a rigid L-shaped frame ABC consisting of a horizontal arm AB (length b = 10...

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