Vacuum Vessel Design

[Phil182]

I was wondering about design calculations for vacuum tanks loaded on trucks and their associated vacuum line accessories. At uni, I only ever worked on pressure vessels, and all calculations were based on a higher internal pressure than their surrounding atmosphere. Will these equations be the same for vacuum? Is there any standards in Australia on this type of design? Any thoughts?

 

[Berndt]

Hi Phil,

Vacuum vessels can fail by buckling. This mode of failure is typically not addressed using standard hoop stress calcs etc.

Try have a look at ASME VIII, Div 1, UG-28 through UG-30. Unfortunately this is the only code I could point you to.

 

[BigInch]

Use absolute pressures everywhere with any flow equations.

"The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward X-CEO BP
"Being GREEN isn't easy." Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com

 

[kacarrol]

I will have to second Kriegfix on this one. Vacuum calcs are a different beast than standard hoop stress calcs. If you google "imploding tanks" you will find a few instances where steam outs of vessels have went wrong. I've included one below.

What ever pressure vessel code you use in Australia will likely have a section about vacuum, or it may be called vessels under external pressure.

Good luck,
K

 

[JohnGP]

AS1210 is the Australian Standard for pressure vessels - it also includes vacuum vessel design, but also allows design to ASME VIII Div1. It also has requirements for transportable vessels.

I haven't had any involvement with transportable vessels, so it would be wise to check local or federal regulations in that respect, for any other requirements.

Cheers,
John