Spring test

[azizur447]

Anybody know how to perform the following test of the spring as mention in ASME Section III Division 1 NB-3594.9.

The permanent set of the spring (defined as the difference between the free height and height measured a minimum of 10 min after the spring has been compressed solid three additional times after presetting at room temperature) shall not exceed 0.5% of the free height.

I think this test has been carried only after the heat treatment.

 

[azizur447]

How do carried out the test of permanent set of a spring

 

[EdStainless]

Yes, after all treatment and stress relief.
You fully compress the spring once, then measure its height.
Them compress three more times and check again.
Most spring guys do something like this withe every lot along with verifying the dimensions and spring constant.

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