Manufacturable Extension Spring

[mprice]

Hi,
I want to design a spring that is manufacturable.
I need to know acceptable values for number of active coils and initial tension for extension springs.
I am using 0.63mm dia spring steel.
I have got 8.5 active coils and an initial tension of 1.337N which is 8.5% of the max spring force.
Does anyone know how/where I can find out more info. on this subject.
Thanks

 

[israelkk]

Any machine design book such as from Shigley or the Machinery's handbook.

However, if spring designing is not your main work and you need to design a spring very rarely or/and your design is for critical use (fatigue, limited space, aerospace or military use etc.) I would recommend seeking the help of a proffesional.

 

[mprice]

Thanks israelkk for you quick response. I only occasionally need to design springs but I like to ensure that what I have designed is at least possible, before I get involved with profesionals.
I haven't got the books you mentioned- I should buy one of them.

 

[mloew]

mprice,

You may want to visit the Extension Springs pages at

http://www.efunda.com

(Engineering Fundamentals). Many online calculators and resources came up with a simple Google search using the keywords spring design.



Best regards,

Matthew Ian Loew
"Luck is the residue of design."
Branch Rickey

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