Spring Inspection Method
Spring Inspection Method
(OP)
I would like to measure the outer diameter of a spring (0.130" ID and 0.030" wire thickness) at free state and measure the outer diameter again when it is compressed at 0.050". Any thoughts as to how to measure the outer diameter of the spring at compressed state? I'm interested to find out diametric expansion of the spring under compression.





RE: Spring Inspection Method
thread1103-227624: Spring Inspection Method
KENAT,
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RE: Spring Inspection Method
RE: Spring Inspection Method
i am unable to find "thread1103-227624: Spring Inspection Method"
will you please elaborate the method discribed
Kedarg6500
RE: Spring Inspection Method
Regards,
Cory
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RE: Spring Inspection Method
I think btrues idea has merit. Fundamentally have some kind of jig that compresses the spring then measure the OD.
Of course, the compressed spring may not maintain good cylindricity which you'll have to allow for.
KENAT,
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RE: Spring Inspection Method
E.g - we had a piston spring for what was effectively a hydraulic cylinder. We mimiced the piston and end cap, and loaded the rod with weights below where it penetrated the end cap. We were also concerend about how much sideways deflection/moment might be created by the spring, tending to push the piston rod off-center, so we used a spherical bushing where the rod passed thru the end cap. This also allowed us to measure the sideways force required to re-center the piston/spring. Results were surprising to us...springs do not always behave as you might think.