RE: [PSUBS-MAILIST] Condensation Reduction Means

I forgot one important reason for installing syntactic foam and then a polyurea coating on the inside of a metal sub. Reducing condensation by a large degree. After seeing how much trouble Karl Stanley has with condensation, I wanted to design in a way to deal with it.

If the moist air can't find a cold surface to condense on then we win.

Szybowski

From: brenthartwig@hotmail.com
To: personal_submersibles@psubs.org
Subject: [PSUBS-MAILIST] KL-250's Syntactic Foam Data
Date: Fri, 10 Jul 2009 00:28:58 -0700

Hi Brian,

I'm installing syntactic foam for a number of reasons. I'll list them in the order I find most important at the moment.

1. Extra Collision protection

2. None Compressible, None Molding Insulation from cold and heat

3. A large amount of hydrostatic load protection

4. Echo reduction

5. Smoothing out the interior for easy cleaning

6. Practice working with Syntactic Foam

========================================================

Syntactic foam is the only foam I know of that will not crush with the hydrostatic pressure I intend to expose it to during wet exit training with this sub. Also mold and mildew love fiberglass and cork insulation. Have you ever had to clean up beer, or that lovely fluid people discharge when they get car sick, out of your vehicle? All Ill need is a garden hose and a shop vac.

I have though of using several layers of the foil bubble rap insulation you see in the hardware store for raping around hot water tanks and what not. Since it will simply compress the bubbles when pressure is applied, and not break them. But you would still have water on both sides of that material that would take some time to dry.

Since I'm replacing the weakest parts of the original K-250 sub design, such as the blown dome and the forward viewport assembly. I plan to upgrade the subs operational depth to 500 fsw. So I guess that would make it a KL-500. ;}

The polyurea coatings are many times used in sealing concrete in large aquariums and ponds. They say if you let them cure long enough they will not harm the fish and other aquatic life. How longs that is, I would expect would depend on a number of factors, such as chemical formula, thickness, location, heat, airflow, etc. I do know that the fast cure coatings like Rhino and Turboliner seem to off gas very quickly. They use these coatings on the inside of Hummers, Jeeps, boats, kitchens, and what not. If you can't smell it any more when you close the hatch I would say your good to go. But it might take a few weeks with some coatings.

Perhaps this is a good place to use the canary in the coal mine method. As for me I prefer to use mosquitos. ;}'

Regards,
Szybowski

From: ojaivalleybeefarm@dslextreme.com
To: personal_submersibles@psubs.org
Subject: RE: [PSUBS-MAILIST] Polyurea Coatings for Submarines
Date: Thu, 9 Jul 2009 20:53:21 -0700

Brent,

Are you insulating the inside of your sub against the cold? If so why the syntactic foam instead of another type? That isocyanurate tends to out gas in think, might want to be carful of that in a closed environment.

Brian

-----Original Message-----
From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org]On Behalf Of Brent Hartwig
Sent: Wednesday, July 08, 2009 9:14 PM
To: PSUBSorg
Subject: [PSUBS-MAILIST] Polyurea Coatings for Submarines

I have two local friends, that spray polyurea coatings commercially. One sprays in on there steel dock weldments and other items. The brand they use is TurboLiner. At the moment I plan to have them spray the interior of my sub after all the syntactic foam is cured.

http://www.turboliner.com/turbo_liner_vs_others.html

"Polyurea is a type elastomer that is derived from the reaction product of an isocyanate component and a synthetic resin blend component through step-growth polymerization.

Practical uses

Truck bed liners
Polyurea truck bed liners form a durable, water and air-tight, permanent liner for the exterior of pick up trucks, dump trucks and steel containers. These durable, easy to clean and abrasion resistant liners protect utility trucks from their harsh duty environments. They also protect against rust and corrosion from damaging trucks and containers. Polyurea liners can also be applied in varied thickness to meet any specific application demand. Sprayed on truck bed liners are available in many colors and can be wrapped over the top edge of the truck bed to provide added protection from impact and abrasion.

Pipe and pipeline coatings and linings
Polyurea coatings and linings are increasingly being used to protect steel pipes from corrosion. Polyurea has demonstrated its ability to last longer than paint and maintenance services and costs are reduced. Polyurea is a great protective coating system for pipes that are insulated with polyurethane foam. Polyureas are also being used to line the inside of water and sewer pipes for infrastructure rehabilitation work.

Bridge coating
Polyurea's ability to outlast paint and fight off corrosion is a major reason these systems are being specified for bridge deck and structure coating by State DOT's around the nation. The most common applications of polyurea coatings on bridges are over steel and concrete.

Joint fill / caulk
Polyurea is being successfully used as a multi-purpose joint fill, caulking and sealant material. It can provide a flexible, durable, weather-tight and traffic resistant seal for all types of building joints, such as expansion joints and control joints in masonry floors, perimeter joints, panels and doors, water reservoirs, etc. It has excellent crack-bridging properties with high elongation and tensile strength. The fast cure time and insensitivity to moisture allows for a quicker installation with a wider application window. Proper surface preparation and substrate condition is always necessary.

Holding tanks

Tank coatings
Polyurea coatings protect steel tanks from corrosion, chemicals, and other natural weather and jobsite elements. With proper surface preparation, substrate condition, formulation choice, primers, and installation procedures, polyurea goes on fast and stays on long. Polyureas are great for extending the life of older tanks and can offer limited structural characteristics as well. These systems can be applied during primary construction or in a retrofit environment. With their fast cure times they are ideal for retrofit since down time is significantly minimized compared to some competing materials.

Tank linings
Polyurea linings are resistant to many chemicals and industrial liquids. With their fast application advantages and ability to adhere to properly prepared substrates, polyureas are ideal for new storage tank primary lining and rehabilitation projects.

Waste water treatment linings
Fast cure, chemical and abrasion resistant, concrete primary and secondary containment linings.

Aquarium lining
Aquariums have also found benefits with polyurea. The ability to form to properly prepared custom shaped walls and themed ornaments make this system desirable. A spray applied, water resistant liner, available in a variety of colors with rapid return to service installation is why facility owners are turning to polyurea.

Landscape & water containment
Landscape designers and contractors have found similar benefits with polyurea. Polyurea is often used to contain water for ponds and pool decorations to form a primary containment liner. Use of geotextile material is common when applying polyurea over dirt. Proper surface condition is vital when applying over concrete and most other substrates.

Marine
Above the water line and below, polyurea can be very effective in protecting steel, aluminum, and fiberglass in a variety of water sport and commercial marine applications. From sound attenuation for fishing canoes, to fish hold liners, to hull protection and bilge liners, polyureas are used in many abrasion, chemical and corrosion resistant marine applications. "

http://en.wikipedia.org/wiki/Polyurea

Sounds like a good product for coating concrete submarines as well.

Another brand of polyurea coatings is http://www.xtremeliners.com/

There is also some interesting polyurea data here in this PDF.

http://www.kta.com/knowledge/PACE2005/Polyurea%20Coatings%20CLO.pdf

Regards,
Szybowski