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guys
the safety issues are paramount
in the design of a 1 ATM sub, redundant everything. A wet subs issues are a
lot easier to deal with, all else fails get out. The hull of a 1 atm sub is
about the only thing that can not be made redundant. a one test to 1.5 times
working pressure is a good start that does nothing to tell use about the effects
of pressure cycles or minor damage. Remember that comet aircraft, or another of
the many that have had fuselage failures.
abs specs are a pain and
expensive to comply with as said before they come from a history of failure.
With that said, there are some areas that money can be saved. gas piping for
example, using swagelok valves rated for the working pressures and hydroed
after installation stops the need for certified valves. total redundant systems
that share nothing are the way to go.
ports are not a place to save
money, while have them built and tested to pvho standards is expensive there are
no backups so bite the bullet a spend the money. if we design view ports to
aircraft standards a k-250 window would be 6.7 inches thick and come with certs
that would track back to the individual chemicals in the acrylic. those of you
who are using off the shelf acrylic sheets should at a minimum test
one port to failure.
Rick m
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