RE: [PSUBS-MAILIST] New comer w/ROV Question

["Karl S. Luttrell" <SDECO@prodigy.net>]

Re:  ROV shaft seals

A double "O" ring with hydraulic fluid in between them makes a very durable
and leak friendly seal.  Mounted on nesting fittings, the integrity of the
seal is easy to verify by the spacing of the two fittings maintained by the
hydraulic oil in between the "O" rings. Has the benefit of double seal, and
if outer ring leaks, inner isolates guts of ROV.  If inner leaks, only a
little electronics friendly oil gets into the guts, outer ring keeps water
out.  Easy to check and service. Remember to micropolish shafts in seal
region.

Karl

-----Original Message-----
From: owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org]On Behalf Of Stan Muller
Sent: Thursday, July 19, 2001 8:02 PM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] New comer w/ROV Question


Jonathan, Pat, and anyone else interested;
   When I was fooling around with my ROV design, one of my major
problems that I encountered was to achieve a  pressure tight fitting on
the motor shafts. When the packing was tight enough to seal, it put too
much drag on the little motors.
   I overcame the problem by mounting a magnet on the motor shaft, then
a solid copper end cap and a free spinning propeller mounted on a solid
axle with a magnet on the prop. It worked, I had a free turning prop,
and no through shaft to seal.
   After feeling proud of myself for my original design, I found out
that pumps have been built like this for years.
For what it's worth, Stan in Mo.