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They have a nice cut-away drawing, with
materials. The coupling wall is vinyl-ester... no eddy
currents!
I did a quick and dirty test today to verify the
drag from eddy currents on a metal wall:
Took two very strong magnets, as one would use in a
coupler, separated them using a couple non-magnetic spacers. Dropped a long
aluminum flat bar between the magnets, and it was amazing how the eddy
currents slowed the falling bar, nearly at the moment of release. There's no way
a metal wall will work with a motor running more than a few 10's of
RPMs.
Mark
----- Original Message -----
Sent: Tuesday, July 31, 2007 4:20
PM
Subject: RE: [PSUBS-MAILIST] Magnetic
coupler
Prior
to this discussion, had been considering replacing several brine pumps at work
with magnetically coupled pumps to eliminate shaft seals (additional benefit
of composite impeller and housing would not react with acid fluid).
Cutting to the quick, some interesting facts concerning the magnetic
coupling:
1.
Able
to handle powers up to 100 HP.
2.
Working
pressures to 200 psi
While
this is a pump, it is easy to see how this technology would easily be
extensible to thrusters (and greater depth [200 psi = ~452 ft.] as the
pressure on components would be compressive, not tensile). The issue
would be the design of bi-directional thrust bearings that are water
lubricated and cooled. The shaft and bearings within the pump were
manufactured from sintered SiC and use the pumped fluid for lubrication.
For those of you that would like further information, see http://www.fybroc.com/html/mag.htm
R/Jay
Respectfully,
Jay
K. Jeffries
Andros
Is., Bahamas
A
skimmer afloat is but a submarine, so poorly built it will not
plunge.
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