Pipe Length Affecting Design Thickness
Pipe Length Affecting Design Thickness
(OP)
Hi all,
I am looking into designing a stabilizer tower for a process application using ASME VIII Div 1 (first time doing so) and have a curiosity question regarding the correlation between design thickness for a shell and the length of said shell.
Some info:
Design pressure is 200PSI@400F, 24" OD, Sa-333-gr6, .118" CA, 50' tall, Full radiography, tower is split into a top and bottom section at 120" from bottom.
My concern is when I run the bottom shell (~120") versus the top shell (~480") the design thickness for the shells differ (.2755" versus .3322") and the only thing I can accredit this to is the length of the top shell.
So i'm assuming that Compress is taking into account the length of the top shell, but if I were to do this calculation by hand I would end up with a min. thickness much less than what Compress is requiring.
I guess my ultimate question is at what point does Compress start to increase the required thickness of the shell?
Is there somewhere in code that requires the length of the shell at some point to be taken into consideration?
Am I potentially just missing something in general?
Any info is appreciated, if I have forgotten to mention a factor that requires more information please let me know and I can provide more info.
Any feedback is welcome.
Thank you!
I am looking into designing a stabilizer tower for a process application using ASME VIII Div 1 (first time doing so) and have a curiosity question regarding the correlation between design thickness for a shell and the length of said shell.
Some info:
Design pressure is 200PSI@400F, 24" OD, Sa-333-gr6, .118" CA, 50' tall, Full radiography, tower is split into a top and bottom section at 120" from bottom.
My concern is when I run the bottom shell (~120") versus the top shell (~480") the design thickness for the shells differ (.2755" versus .3322") and the only thing I can accredit this to is the length of the top shell.
So i'm assuming that Compress is taking into account the length of the top shell, but if I were to do this calculation by hand I would end up with a min. thickness much less than what Compress is requiring.
I guess my ultimate question is at what point does Compress start to increase the required thickness of the shell?
Is there somewhere in code that requires the length of the shell at some point to be taken into consideration?
Am I potentially just missing something in general?
Any info is appreciated, if I have forgotten to mention a factor that requires more information please let me know and I can provide more info.
Any feedback is welcome.
Thank you!
RE: Pipe Length Affecting Design Thickness
- Length of the shell is a factor in external pressure calculations. SO if you have full vacuum, it would affect the thickness.
- Also, if you set the liquid level of the vessel to be the top of the tower, the corresponding weight would translate to a pressure that is highest at the bottom. This extra pressure would require a thicker shell.
RE: Pipe Length Affecting Design Thickness
RE: Pipe Length Affecting Design Thickness
RE: Pipe Length Affecting Design Thickness
RE: Pipe Length Affecting Design Thickness
Thanks for the input!