How to decide nominal thickness
How to decide nominal thickness
(OP)
Dear All.
Can anybody reply me to know and calculate nominal thickness. I used pressure vessel plate 516 gr.70 minimum thickness is 28..how should be nominal thickness?
Thank in advance
Can anybody reply me to know and calculate nominal thickness. I used pressure vessel plate 516 gr.70 minimum thickness is 28..how should be nominal thickness?
Thank in advance





RE: How to decide nominal thickness
RE: How to decide nominal thickness
Cheers,
gr2vessels
RE: How to decide nominal thickness
RE: How to decide nominal thickness
RE: How to decide nominal thickness
Mill under-tolerance for plate is no more then 6%. So add that to your minimum thickness and see what is the next available thickness from the supplier.
RE: How to decide nominal thickness
If your customer needs 28mm and 400°F, and the next standard size is 1-1/4" [31.7], use it or 1-1/2" [38]. Then declare the Design Temp to be 600°F, as 516-70 does not have a strenght derate until >600°F. Now the customer has enough Corrosion Allowance - C.A. - to run for decades w/o needing a thickness-mandated repair, and he can increase his operating temperature without having to pay for an Alteration to increase tne MAWT. Most customers want to increase thoughput after a decade or so of running, so they typically need to increase the Max. Allowable Working Temp.
The inspection, verification of Code calc's, and certification for an Alteration costs about $2,000, without any 'work' being performed on the vessel.
RE: How to decide nominal thickness
As on that thread, I again strongly suggest the original poster get significant additional professional help before committing any people inside his proposed vessels underwater.
RE: How to decide nominal thickness