How to calculate head plastic buckling pressure during the hydro test

[acbdcl]

I need a formula to calculate the plastic buckling pressure for a torispherical and an ellipsoidal heads.
What is ECCS formula for this plastic buckling pressure ?

 

[JoeTank]

That subject has been addressed in a WRC Bulletin. I suggest you go to their website and track down the bulletin number. What is ECCS?

Steve Braune
Tank Industry Consultants

http://www.tankindustry.com

 

[acbdcl]

Steve

ECCS is European Convention for Constructional Steelwork and published the following document:
- "Buckling of Steel Shells, European Recommendations", 1988.

I need calcute the stress during hidro test for an ASME vessel. The formulas of ASME code (Addenda 2003), for torisherical heads, overestimate stress in this condition.

 

[arto]

Harvey's "Pressure Component Construction" Ch. 2.6.4 has a section on this. Basically, if axis ratio a/b > 1.42, this can be a problem.

It makes quite a memorable sound when it goes, too [as in "what the #$%%#@ was that?"].

We had one once on a "non-code" [as in "it doesn't have to be engineered, it's less than 15psi"] tank with shallow, thin ends ("to save $$&quot. The shop boys were leak testing the pipes, with city pressure in/ a partly open ball valve on the outlet for back pressure. A loud Boinnngggg resounded throughout the shop. The tank knuckle-buckle looked just like the picture in Harvey. Funny how the immutable laws of physics hold true, even when managers hold a meeting & decide they don't apply. "Get out the fender tools, boys!!" ;-)

 

[bogu]

acbdcl

The pressure vessel design book by H Bednar has a formula for calculating the collaps pressure in dished ends.

Bogu