Re: PVC

[VBra676539@aol.com]

In a message dated 7/1/99 1:29:27 PM, fphillips5@excite.com writes:

<<Hi Vance and group,  Regarding PVC crushing at 400 ft, I wonder what company
draws huge PVC pipes in an extrusion method could just set their tooling for
a 6", 9" 12" wall thickness and run a length of 20 ft or so at a 7 ft inside
diameter.  Then chem weld twin conical or hemispherical end caps at the same
12" thinkness that fit it perfect compression tongue and grove joints and
also chem welded view ports.  Seems as though the crush depth would be good,
hull never rusts, easy to drill thru hull holes with extra PVC backing at
those thru hulls.  

Then just use a very thick clear lexan viewing port(s) attached on the
outside of the PVC hull with a 2 in overlap on the outside and sealed via a
little o-ring groove and some mere location stainless small dia bolts.  The
same end cap design could be used for a short tower with huge oversized PVC
hinges and stainless locks for a nice pilot access hatch also with viewing
ports.  

Internal PVC bulkheads and stringers could also be chem welded as required
to give you a 100% margin over your reqired crush depth.  All equipment,
ballast, motors, air and communications can be in smaller twin isolated
exterior pods that have the diving planes, propellers, etc.  Does this make
any sense.  Have at me men. 
I'm not thinned skinned.  F. Phillips  
>>

I don't know anything about structure on poly materials, but suppose you 
would be right about it. There is a PVC pipe manufacturer here in town who is 
a friend of a friend. I'll try to bubble the question up to him and see what 
he says. Maybe there's an easier way than retooling to make the big stuff you 
are thinking about. I've seen some pretty hefty pipe for water and sewer 
lines, though. Maybe it's already available just waiting for some innovator 
to jump in.

Some of the British 1-atm / 1-passenger workboats (Wrangler, maybe, and 
Mantis?) had spun fiberglas hulls, I think. Seems like they had aluminum 
endcaps in the stern and plexi domes for a bow, but don't quote me. I never 
worked with any of them. Graham Hawkes designed these in the 70s and had some 
success for a while. He's a big believer in synthetics--witness his Deep 
Flight. However, Phil Nuytton is building his vehicles in steel, which may be 
suggestive. Simultaneously (and at the same time) he (Phil) is also 
developing composites for the Exo. Don't know what that means for the 
pocketbook, but surely there is some hard data out there somewhere on these 
materials.

Vance