PD 5500 Vacuum

[Clareok]

Hello,

Were having a problem in getting a vessel to pass full vacuum. The vessel shell is out of 3mm and we can only fit one stiffening ring due to nozzle placement..

We cannot get the moment of inertia sufficiently with one ring. Is there another way around this?

J

 

[SnTMan]

Clareok, you can:
1) Lower vacuum pressure
2) Lower vacuum temperature
3) Change shell material
4) Increase shell thickness
5) Decrease shell diameter
6) Decrease shell length / add lines of support

Option 4) is usually the least expensive at the design stage, option 6), can you bridge a nozzle or put rings inside?

Regards,

Mike

 

[gr2vessels]

If you have a manhole, you might consider internal stiffening rings as per UG-29.
Cheers,
gr2vessels

 

[gr2vessels]

Oops,
I forgot your design is per PD5500, I couldn't check it now, but I'm sure the principle of internal rings applies to PD500 too.