Re: [PSUBS-MAILIST] Pressure hull materials

[Ian Roxborough <irox@ix.netcom.com>]

On Fri, 20 Dec 2002 12:07:18 -0500
Michael B Holt <tlohm@juno.com> wrote:

> On Fri, 20 Dec 2002 08:27:31 -0800 (PST) Ray Keefer writes:
> >
> >Certainly the corrugations would act as ribs to keep the sides from
> >caving in. Wouldn't the corrugations pre-dispose the hull to 
> >collasp acordian style?

Well, that sounds like a nice thesis topic for somebodies masters degree.
He talks about the different failure modes of tin cans, but doesn't
really mention acordian style failures.  Although, if you had end
cap surfaces that where greater than the cylinder's surface, I could
imagine the longitudinal force could fold the corrugations in a failure
as you describe.

A little side note on tin cans you get beans and other food in:
The reason they have ribs or corrugations is due to the fact that
to tin some food you need to suck all the air out of the tin first.
The corrugations give the tin extra strenth without making it
heavier or using any framing rings (since while there is a vacuum
inside it is under external pressure).

> Good idea.  I'd not thought of that.   It might be sufficient, then,
> to add internal stiffening rods going the length of the thing.
> 
> The book Ian referenced might help here.  Ian, can you give
> more information on it?   Is it in print?

I posted a mini review of the book in question to the list a
while ago, you can read it here:
  http://www.psubs.org/mlist/archive/0112/msg00271.html

It's probably not everybodies cup of tea, after about page 20
it gets pretty advanced and bleeding edged.  I couldn't really
imagine any psubs trying out any of the latest ideas talked about
in the book (not until they are more proven anyway).  But saying
that, I really enjoy reading about what could be future submarine
pressure hull design and construction techniques.

It's still in print and still costs $55.

Ian.