Spring Stresses

Allowable Working Stresses for Springs.—The safe working stress for any particular
spring depends to a large extent on the following items:
1) Type of spring — whether compression, extension, torsion, etc.;
2) Size of spring — small or large, long or short;
3) Spring material;
4) Size of spring material;
5) Type of service — light, average, or severe;
6) Stress range — low, average, or high;
7) Loading — static, dynamic, or shock;
8) Operating temperature;
9) Design of spring — spring index, sharp bends, hooks.