Jay,
On my design I have this large soft ballast tank that happens to be
made out of ferro-cement, it's basically a large volume for getting me as
far out of the water as possible for surface operations. It has a interior
displacement of 4800 lbs. Thats a volume of around 74 cu ft and then
considering the wieght in water of the ferro skin of approximatly 600 lbs.
This ballast structure is going to be lifting the equivilent of a K-350 out
of the water, exept my cylindar will have a bit different dimensions.
These figures are a bit sketchy because in the calculations I rounded off
some parts of the sturucture to make it less complicated to to figure out
and I'm not entirely confident in the wieght calculation of the
ferro-cement structure. The wieght of ferro sturcture could vary anywhere
from 8 lbs/ sq ft to 12 lbs/ sq ft so I won't really know that until I
get it in the water. Anyway I want to be able to "pull the plug" on the air
in the ferro ballast and not have to wait around for a hundred years to go
under, that's why I'm looking for large valves for that function. Those
valves will not see any pressure so bronze may allow for a larger opening.
Or maybe a mushroom valve.
Brian
> -----Original Message-----
> From: owner-personal_submersibles@psubs.org
> [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Jay K.
> Jeffries
> Sent: Saturday, January 03, 2009 8:55 PM
> To: personal_submersibles@psubs.org
> Subject: RE: [PSUBS-MAILIST] Soft ballast venting valve
>
> Brain,
> Depending on the pressure service you may find bronze valves on PSUBS.
> Some builders use all stainless steel for possible greater dependability.
> What is your designed service depth and your design safety factor...the
> one times the other gives you the MINIMUM rating for the valve (and
> associated piping and fittings). Depending on how the bronze and SS is
> used there may be corrosion issues, good paint and zincs may solve some of
> those issues if they develop. Using all SS while costlier simplifies
> design and maintenance issues.
> R/Jay
>
> Respectfully,
> Jay K. Jeffries
> Andros Is., Bahamas
>
> As scarce as the truth is, the supply has always been in excess of the
> demand.
> -Josh Billings
>
>
>
>
> _____________________________________________
> From: owner-personal_submersibles@psubs.org
> [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Brian Cox
> Sent: Saturday, January 03, 2009 11:43 PM
> To: personal_submersibles@psubs.org
> Subject: RE: [PSUBS-MAILIST] Soft ballast venting valve
>
>
> Jay,
> Would bronze valves be a good choice? Why don't we see any
> bronze valves on pubs ? How do bronze and stainless get along together?
>
> I know, I ask alot of questions.
>
>
>
> Brian
>
> -----Original Message-----
> From: owner-personal_submersibles@psubs.org
> [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Jay K.
> Jeffries
> Sent: Saturday, January 03, 2009 6:58 PM
> To: personal_submersibles@psubs.org
> Subject: RE: [PSUBS-MAILIST] Soft ballast venting valve
>
> Brian,
> Stick with the bronze valves as your suggested modified farm valves
> will only be trouble.
> R/Jay
>
> Respectfully,
> Jay K. Jeffries
> Andros Is., Bahamas
>
> As scarce as the truth is, the supply has always been in excess of
> the demand.
> -Josh Billings
>
>
>
>
> _____________________________________________
> From: owner-personal_submersibles@psubs.org
> [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Brian Cox
> Sent: Saturday, January 03, 2009 9:49 PM
> To: personal_submersibles@psubs.org
> Subject: RE: [PSUBS-MAILIST] Soft ballast venting valve
>
>
> Thanks Jay,
> Lined SS valves ? These butterfly valves that
> we use here on the farm are usally a cast iron body with a metal disk (
> the "butterfly") in the middle for the shut off device. There is rubber
> around the disk as well as rubber around the perimeter of the mating
> opening of the cast iron valve body. It would be easy enough to replace
> the metal disk with stainless and maybe I could epoxy the cast body. or
> possibly find a bronze one.
>
> Brian
>
>
> -----Original Message-----
> From: owner-personal_submersibles@psubs.org
> [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Jay K.
> Jeffries
> Sent: Saturday, January 03, 2009 5:49 PM
> To: personal_submersibles@psubs.org
> Subject: RE: [PSUBS-MAILIST] Soft ballast venting
> valve
>
> Brian,
> Ball valves typical get tight from not operating the valve
> on at least a scheduled basis. Care has to be given that sand and/or
> calcite deposits occur in the valve which can damage the sealing surfaces
> or scratch the ball. Butterfly valves may be an option as they have a
> limited capability to throttle flow where ball valves tend to be all or
> nothing (100% flow or 0%). Butterfly valves can also be affected by sand
> and calcite deposits. Butterfly valves are available in SS but are very
> pricey when found. Another option to contain costs is to use SS lined
> valves vs. a complete body of SS.
> R/Jay
>
> Respectfully,
> Jay K. Jeffries
> Andros Is., Bahamas
>
> As scarce as the truth is, the supply has always been in
> excess of the demand.
> -Josh Billings
>
>
>
>
> _____________________________________________
> From: owner-personal_submersibles@psubs.org
> [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Brian Cox
> Sent: Saturday, January 03, 2009 8:39 PM
> To: Personal_Submersibles@Psubs. Org
> Subject: [PSUBS-MAILIST] Soft ballast venting valve
>
>
> Happy New Year All,
> Does anybody have a suggestion for a ballast venting valve
> for a soft tank ( my ferro structure ) that is around 1 1/2" diameter or
> maybe 2" , I will most likely use a stainless ball valve but I'm worried
> that eventually it is going to sieze up on me. It seems like those ball
> valves get awfully hard to turn after a while. The butterfly valves that
> I've seen ( for farm irrigation ) seem to turn easier , but I haven't seen
> them in stainless.
> Thanks
> Brian, Ventura, CA
>
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