Joe Strout wrote:
Of course, *replacing* the O-ring, or otherwise doing maintenance on
this giant rotating seal, could be a real PITA. Certainly something to
plan for up front.
For maintenance you could start up the stationary part or stop the
moving part. Then you just put in a temporary inner seal and work
on the O-ring to your heart's desire.

Or the connector consists of a tube with an O-ring on both ends, then
you can couple the tube either to the still or to the moving part and
always have one O-ring at rest relative to the tube and the connected
part. Then maintenance ought to be easy too.

You can minimize leaks further by pressurizing the connection
only when needed.

Also, for long term survival I think that the air locks pose the bigger
problem. And accidents of course.

OTOH, earth loses a bit of air too (http://tinyurl.com/nxqqu) but during
the last few billion years it wasn't much of a problem, so, depending on
the size of your station, a few spoonful per day may be tolerable.

Lots of Greetings!
Volker
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