Belleville Spring Constant Calculation

[tazengr]

I am trying to calculate the spring constant for a Belleville Washer type spring. The dwg says that the spring force is 33 lbs. when fully collapsed. However the difference between free height and collapsed height is .0065 in. This gives a spring constant of >5000 lbs/in.
Which seems rather high.
I know the material and dimensions of the spring. Is there another way of calculating the spring constant.

Furthermore I would like to calculate the effective spring constant when nine of these springs are stacked opposite one another. On wikipedia it has a formula that I used and I ended up dividing the spring constant by 9.

Is this correct?

Thanks.

 

[israelkk]

Yes, dividing by 9 is correct if they stacked opposite one another. The rate is usually very high. If it is a standard catalog item can you give the maker and the catalog number?

http://israelkk.googlepages.com/home

 

[unclesyd]

About the middle of the page, Engineering Springs.

http://www.fandisc.com/Index.html