How to reduce thickness in Compress?

[Civilpetro]

I have a pressure vessel that has an internal pressure of 900psi and temp of 970F. I run the calcs and compress gave me a thickness of 4" for the vessel and 6" for the heads. I just want to make sure that I can not reduce the thickness anymore. I know for full vacuum chambers I can reduce the thickness by using stiffeners.

 

[TGS4]

You could change materials. That's about it.

 

[vesselfab]

What kind of heads are you using that are so much thicker than the shell?

 

[Civilpetro]

TSG4,

I can't change my material. It is specified by the customer. Thanks for the input.

 

[Civilpetro]

Vesselfab,

I tried using F&D head at first then ellipsoidal. Both of them came out to about 6" thick. A tapered head will possibly be the ending to this vessel.


CivilPetro

 

[vesselfab]

that's odd

generally a 2:1 ellipsoidal is just a little thinner than the shell, all things being equal.

 

[TGS4]

How about you share some details: OD, pressure, material. You'll probably get more help that way.

 

[Civilpetro]

OD = 78" Int P = 900 psi Mat'l = SA240 347 T = 970 F

 

[TJOrlowski]

Design Code? Joint designs? What type of radiography? How are you attaching the heads to the cylinder?

I don't use COMPRESS but I did some very quick numbers using ASME VIII, D1 and came up with required thicknesses less than what you gave.

-TJ Orlowski

 

[vesselfab]

maybe you can go to hemi heads to reduce thickness

 

[Civilpetro]

At first I used no RT. Then I used Full UW-11a Type 1 for the circumferencial and longitudinal seams. I came up with 3" for both of them. I think that's the thinnest I can make it. Thanks for the input.