# Spring selection

1. Oct 22, 2009

### joeTTU

For Intro to Design I am working a problem where I need to find the volume of a spring. The instructor hinted that you CANNOT use volume of a cylinder and subtract inner diameter. Please help. Thanks

2. Oct 22, 2009

### stewartcs

What information is given in your problem statement?

CS

3. Oct 22, 2009

### joeTTU

NVM got it the formula for vol is =(pi*d^2)/(4)*pi*D*Nt

Nt=# of turns

4. Oct 22, 2009

### stewartcs

Correct!

CS

5. Oct 22, 2009

### joeTTU

Let me ask you this though any insight in what you consider design goals for springs with static loading?

6. Oct 22, 2009

### stewartcs

Well off of the top of my head I would say the spring constant, material (e.g. will it be used in a corrosive environment), and dimensions. Probably some more that I can't think of right now!

CS

7. Oct 23, 2009

### FredGarvin

On top of what Stewartcs mentioned, free height vs. solid height vs. working height are very important. Also, in static springs, stress relaxation is always a concern.