Calculation of ellipsoidal head's diameter

[Adrianos81]

Hii every body,

hope that anyone can help me how to calculate the diameter of raw material if i want to make an 2:1 ellipsoidal head. Is there maybe a certain formula for that case?

Thanks.

Best rgrds,
Adrian

 

[vesselfab]

are you speaking about a blank to press or spin a head?

each manufacturer has slightly different requirements

 

[hakkik]

take a look at this

http://www.kartalbombe.com.tr/KBSPDF/asme.pdf

the value you look for is Dp

 

[Adrianos81]

vesselfab: thank you for your quick response. In this case, i mean: before we press the plate into form of ellipsoidal head, we need to calculate the required diameter to meet the fabrication spec of ellipsoidal head. could you give some information according to your experience? thanks.

hakkik: thank you for your reference, will try this formula

 

[chaulklate]

Calculate surface area of a 2:1 head using A = 1.084D^2. This does not include any straight flange.

 

[boilerone]

Hello vesselfab,

I have two formulas from my 'boiler manufacturing text book' and both are practically used in shops:

For standard 2:1 elliptical head,

Formula 1: D = 1.223*d1+2*h*K0+2*delta
Formula 2: D = sqrt(1.38*(d1+S)^2+4*(d1+S)*(h+delta))

D, required diameter of the raw material before pressing
d1, ID of the head
h, height of the straight part
K0, elongation factor of manufacturing by pressing, typically K0=0.75
delta, reserved for machining
S, thickness of the head

I have also the more complicated formulas for non-standard head if you need them.

 

[vesselfab]

thanks...but I don't need it.

so we have three (3) formulas so far

as i said...each manufacturer is slightly different in blank diameter