Yep! Plexiglas is a trade name for
Acrylic.
Some one wrote that you should get a copy of
PVHO. It's a good idea if you can get a look at it. In there, you'll
find the answers to most of your questions.
The one thing that PVHO didn't answer for me was
how to deal with thermal expansion of the acrylic lens. It's a great set
of standards to design with if your viewport is in a pressure chamber in a
building, but a sub viewport can be exposed to 130 degrees F in or better in the
hot sun and 30 degrees F in cold water. Mine has already seen that
extreme. If I followed the PVHO exactly, my external O-ring seal would now
be stuffed in the annulus between the lens and the viewport housing after
my deep water test in cold water.
Dan H.
|