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Vance, That’s just great stuff and I hope I’ll be
able to get a copy of your book Downunder. When are you planning on finishing
it. I am trying to find books on sub info and design. I have Stachiws which is great and Busby’s
Manned submersibles. Anyone have any other recommendations on other books that
have detailed tech info such as snorkel sealing etc. I am collating all the good info I get off
p-subs into a document so it is easy to find in the future. Big problem is I
came onto the site late in the piece. Anyone else have collections of technical
pearls? Thks, Hugh From: owner- See below, as best I can
answer: Hi Vance, I would love to have more practical
oilfield experiences on the dome sealing or installation practices from
you. What type of grease, Vacuum grease; high density, low
oxygen stuff, thick as glue. What fit / clearances were they on
diameter. All this
information is available in Stachiw, and should be referred to for planning,
construction and fit-up. What type of domes 90 – 120 degree or 180
degree. Perry
and Hyco both used outer dimensions for their ports, and tailored the conical
mating surface to whatever it turned out to be for that size. Perry had
36" ports on most of the boats, Hyco used 1 meter (40"). The dome
angles ran 113 degrees or so from Perry, and I don't remember exactly what on
Aquarius and Leo (both of which I piloted). Something greater than 113, I
expect. You could work it out easily enough. For Aquarius, a 24"
radius, 40" OD for the window...the chord height would be, um...well, I
don't remember. I'd say 120 degrees or so for the inclusive frame angle, at a
guess. Where were the O’rings placed? The early ports (both flat truncates
and dome segments) used o-rings in the seating area. Long term testing showed
this to provide unwanted stress on the acrylic, under test circumstances, so
later versions used the outer diameter corner for an o-ring from Perry and
neoprene gastkets under the retaining ring for Hyco. There are any number of
pictures in the books about viewport design. We never had a problem with them,
but if you look at the early stuff, you'll see o-rings halfway down the window material,
but in later boats, it's mostly hidden under the retaining rings. What material were they using for the
gasket/dome face etc.
For normal duty, neoprene o-rings or gaskets work just fine. There are issues
in very cold water where the neoprene fails to regain its shape in a timely
manner, and red surgical rubber was used for that application. As for
reinforcement frames in the hull, Perry used regular hull material, whatever
that was, sandblasted and painted, then fine sanded for smoothness (hatch seats
and what not were monel clad, just for your trivia answer of the day). Hyco
used stainless steel forgings, which cost more initially, of course, but
were for the most part trouble free. How were the vacuum tests done. (Ie I cant
imagine people sitting inside with soapy water in a vacuum. ). Vacuum tests were simple. Just put a
vac gauge in the system, pump the hull down to whatever it would take, and then
close everything off and watch the gauge. If it leaked, we'd assume initially
that whatever we had been working on was leaking, and redo it. Otherwise, it
might be a LONG night looking for some other weepy o-ring penetrator.
Typically, this never happened. Maintenance was such that rust, any rust at
all, was corrected in a timely manner, and the subs were overhauled on a
routine basis so that the critical o-ring surfaces were renewed before any
problems arose. This sort of information is like
gold. How can we get hold of operations manuals
for some of these things? I don't know where you'd find that stuff these days. All of us have
bits and pieces, of course. I've got an ops manual for Pisces class boats, and
for the JSLs, oddly enough, but not for the Perry's, which is what I operated
for the most part. I can't for the life of me tell you why that is so, but
there you go. I'm writing a book about the period, and have a bunch of the boys
digging through their junk drawers, so maybe something will come from that. Listening hard to your experiences,
Thks, Hugh From: owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org]
On Behalf Of vbra676539@aol.com Quite useful. We always used a vacuum test to verify hull integrity
after working on penetrations or hull seals on one of the oil field boats.
Also, it's the best way to install one of the big dome segment viewports!
Grease the mating surface, have two or three people stand the thing in place,
lean on it while the vacuum takes hold, and then install at your leisure (while
running the pump continuously, of course). Hi Jens. That's right. A "
perfect" vacuum is not possible, and that method would have limited use as
an indicator of hull strength. It is fairly inexpensive though, and would ,
like you said, be useful in checking for leaks. Frank D. Gas prices getting you down? Search AOL
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