When I need to predict the service life of compression coil springs, I usually use the JIS B2704’s “Torsion stress-fatigue strength diagram”, but is there a calculation formula that gives more specific values? There seems to be a method of predicting the service life from the Goodman diagram, S-N curve, etc., too, but I did not know how to obtain a specific numerical value.
Also, is the S-N curve diagram of spring materials such as piano wire available?
Thank you for writing to us, Aki!
Unfortunately, there is no formula for calculating the number of individual usages of compression coil springs. Since the lifespan varies to some extent, it seems that specific and detailed numerical values cannot be obtained.
In addition, JIS B2704 publishes the “Torsion stress-fatigue strength diagram”, but does not publish the S-N curve diagram for each spring material.
For reference, we will send you the document about the materials’ lifespans by email!
