----- Original Message -----
Sent: Wednesday, June 20, 2007
03:25
Subject: Re: [PSUBS-MAILIST] concrete
encasement for thruster
Hi Brian,
Interesting Idea. One problem that will need to be addressed
is the fact that concrete shrinks as it cures. Not a great deal, but it does
shrink non the less.This would make it difficult to maintain a tight bond at
the seal mating surface.
Best Regards,
Jim Kocourek
----- Original Message -----
Sent: Tuesday, June 19, 2007 11:15
PM
Subject: [PSUBS-MAILIST] concrete
encasement for thruster
Has anybody
considered encasing a thruster motor in re-enforced concrete as a way
of isolating the motor from the seawater and pressure? If you could
first seal all of the openings where you don't want cement with silicone or
equivalent and then route your electrical wires thru an epoxy potted section
I think it could work. The motor shaft would have to be a good
ceramic seal.
Since the cement would be in
contact with the motor housing you would probably get good heat transfer to
the cold seawater also. After the cement has cured coat it with
an epoxy.
If you had a malfunction, like a leak,
or some other problem you could cut open the cement with a carbide blade,
take the motor out, and then just pour a new concrete encasement
very cheaply.
Brian Cox