Weight of Pressure Vessel F&D Head: 1

[farhan007]

What is the shortest, easy and quick procedure to calculate the weight of the Torispherical Dished Head? How can I set a formula for my own use to calculate this kind a heads? Waiting for your positive replies.

 

[TomBarsh]

There is no mystery here (unlike for semiellipsoidal heads): the geometry is well-defined and is mathmetically tractable (unlike for those semiellipsoidal heads where you run into elliptic integrals, which are difficult to solve. Then again, I just got out of bed and maybe those SE heads aren't as bad as I am thinking at the moment...nope, they are that bad, just looked at my spreadsheets).

Anyway, F&D is simply another term for a torispherical head, which is comprised of the knuckle and the spherically dished top. You can derive an exact expression for the arc length of material along a cross section, then use Pappus’ theorem to find the volume, then use volume x density to find the weight. This is probably a good exercise is geometric layout (finding the angle of intersection, the centroid, etc) for a young engineer.

Then again, I found this thread in eng-tips by using Google

http://www.eng-tips.com/viewthread.cfm?qid=27356,

a discussion about head weights. Although the expression given for weight of the torispherical head is approximate only and will not be as accurate as the one you will derive. Or you might try Google to locate more information. But I guarantee that deriving the formula on your own will have its own rewards.

 

[hakkik]

Another way and i think much easier one.

Almost every head manufacturer has formula for estimating "disc diameter"(which eventually became head after forming process). Calculate disc diameter then find it's weight. Plain, simple algebra

Antonius:

http://www.cms-server.nl/upload_fil/2/Abstract from Technical brochure Antonius.pdf

KBS:

http://www.kartalbombe.com/KBSPDF/torisferik.pdf

 

[N2010]

I was having the same issue with weights of F&D heads until I used the links posted above by Hakkik. Thanks

Wrote a excel and verified cals by Solidworks2010.
Here is the but.....
I assign the material in SW2010 as 316L(SG:8.0) which worked out the same as the excel, but if you are using material such as C22(SG:8.69) which has a density which is nearly 10% heavier then 316l grade on a large vessel need to consider the difference in density.

Any Suggestions??

Niall