Blind Flanged on reactor vessel - Thickness and shape

[Esbirinai]

I need to performe a pressure hydraulic test on a reactor vessel which has a diameter of aprox 3 meters and an opening on the top of about 1,5 m diameter long.The pressure test will be 30 bar.
I was thinking of installing a blind straight flange on the opening but i was told that the flange should be spherical (dished).
Is this true? How do I set the thickness for the flange?

Thank you

 

[unclesyd]

Need a little more information.
Is the opening a nozzle?
Does it have a flange or just a stub end ? If a flange what type?
If not a nozzle, just a hole, how do you propose to test the vessel after the a permeant closure is made?
If this is stub end a dished head will be was to go. Still come back with more information.

 

[SnTMan]

UG-34 for flat heads

 

[Esbirinai]

The opening has a flange that supports the motor with a agitator. That flange has to come off with the motor and with the agitator to perform the hydraulic test.
After blinding that opening there are other inlets on the vessel that will make it possible to pressurize,

ES

 

[waskillywabbit]

Depending on the diameter of this opening, which is unclear to me, it might be cheaper to use some type of head (2:1, F&D, ASME 80:10, pipe cap) as a "blind" for the test than actually using a blind. You really need someone familiar with your local code to provide you with some assistance.

Brian

http://www.mcabeeconstruction.com

Opinions expressed are my own and are not those of the company.

 

[prex]

There is not a requirement for a blind used for hydrotesting purposes to be flat or domed: only practical considerations may orient your choice.
The use of a flat blind with stiffening ribs would be a normal choice, the alternatives being:
-a flat blind without ribs: the thickness in this case would be of the order of 100 mm, likely more than the existing flange thickness, so you could need buying new bolts...
-a domed end (semi elliptical, or a dish per fig.1-6(d)), but this one must be welded to a flange, and the construction of the flange alone could cost more or the same as a full blind with the same thickness.
Of course in all cases, and especially for the ribbed cover, you need to calculate what you do, unless you want to build the cover at least two times...

prex

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