Div. 3 - monobloc

[henderrj]

I'm taking a first look at division 3, and I came across the term "monobloc", but I can't seem to find an actual definition for it. I would assume they mean that the shell is machined from a single block of steel. Does anyone have experience with mono bloc, or could you point me in the right direction? Thanks in advance!

 

[AWDMIKE]

I'm only somewhat familiar with Division 3 but here's what I can find.

My understanding of the term monobloc is that it is a solid vessel wall which has been fabricating by a forging. I believe though that the term is reserved for any "solid wall" which is not layered. Apparently it's not that easy, as while looking through Division 3 (KD-801) there are times when you consider wrapped-welded-layered vessels as monobloc vessels (though I believe these are for calculative purposes only).

For hydroprocessing reactors it is somewhat common to use forgings as entire "courses" of the reactor. This component arrives at the reactor fabricator as a large cylinder (and not a flat plate). The adjacent courses are all often made from flat plate rolled into cylindrical shapes.

Would you be able to provide more on what it is you are looking for? I'm sure there are numerous papers, code cases, interpretations, code references, etc. that can be of help to you.