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yankeefan21
08-10-2007, 14:56
Do they sell carbon fiber tanks for SCUBA? If so, why are they so hard to find?

medic001918
08-10-2007, 15:22
I've never seen them. And I doubt they're made. Many people use a heavier material such as steel for tanks since they need the weight to offset their bouyancy. A carbon tank would be light, but would always be positive and you'd have to carry extra weight somewhere to compensate for it.

Shane

fire diver
08-10-2007, 16:14
Ditto what medic said. They don't sell them, becuase there's no market for them. Why carry a 4500 psi tank that weighs 5 pounds, but needs 40 pounds of lead to sink it? Plus they have to be hydro'ed every 3 years instead of 5, and have a service life of like 12 years. After that, they are required to be destroyed.

FD

cummings66
08-10-2007, 18:13
http://www.luxfercylinders.com/news/releases/20021022b.shtml

These are composite tanks.

cummings66
08-10-2007, 18:49
I forgot to add, the last two are the tank specifications. The tanks aren't that horrible, lighter weight than the same size steel tank would be for example but about 3 lbs positive empty.

http://www.luxfercylinders.com/products/scuba/specifications/us_imperial.shtml

fire diver
08-10-2007, 18:50
It's five years after that press release, and still I haven't heard of anyone diving them or shops selling them.

FD

fire diver
08-10-2007, 18:54
I forgot to add, the last two are the tank specifications. The tanks aren't that horrible, lighter weight than the same size steel tank would be for example but about 3 lbs positive empty.

http://www.luxfercylinders.com/products/scuba/specifications/us_imperial.shtml

Well, now THAT'S interesting. Much different composition than our fire service tanks. Those listed look quite nice in their characteristics. I wonder what the price is? I wonder if they still fall under the 3 year hydro and condeming rules?

cummings66
08-10-2007, 22:20
I have trouble getting good reliable 3500 psi fills, can you imagine a fill of 4350 psi? You'd never find good fills anywhere. I suspect that is one reason you don't see them, the second is cost. I'd imagine that it's through the roof. First did you notice the valve threads being different, that means a low volume valve and also tank. One way products become cheaper is by mass production. This one is very low and I bet extremely expensive.

I have also by the way run across a place that sells these tanks, or rather they can sell them. I never filed that info away but I suspect a call to luxfer Monday could tell you where to find them.

Interspiro made tanks similar to this as well for what it's worth. I don't know if you could find them in the US but they do exist outside of the US and are very expensive according to my LDS. He's a fanatic of that product name/company and has lots of trivia stored away, pictures and all.

From what he told me a long time ago I gather it was a complete diving system much like the fire SCBA systems by Scott, MSA, Draeger etc. I don't think you could buy one item, it was a matched set and probably for the same reasons the Luxfer tanks aren't common. I bet it cost as much as one of the good SCBA setups do.

At this point it's all useless trivia, I know they exist. If anybody here could say what the price is Joe or Larry could. They sell Luxfer tanks and I'll wager have seen it at DEMA.

fire diver
08-11-2007, 09:24
I have trouble getting good reliable 3500 psi fills, can you imagine a fill of 4350 psi? You'd never find good fills anywhere.

Heh, I can! I fill 95% of the time here at the fire station. I'm the one in charge of the compressor and cascade system anyway. Our cascade is filled to 6000, and the fill station is regulated down to 4500 for our scba.

FD

yankeefan21
08-13-2007, 09:27
I have trouble getting good reliable 3500 psi fills, can you imagine a fill of 4350 psi? You'd never find good fills anywhere.
Our cascade is filled to 6000, and the fill station is regulated down to 4500 for our scba.
Same here. If your local volunteer fire dept is using the newer SCOTT's, they have either a cascade system or a compressor that fills to 5000-6000psi. Filling a tank to 3500 is a simple matter of adjusting the tank pressure - which is cake to do on the fly.

Thanks for the links, cummings. 3lbs positive isn't TERRIBLE - but I guess I wouldn't actually need all that air anyway. I typically start to approach my decompression limits long before running out of air. I just thought it might be nice for diving against stronger currents when you actually suck down some air.

Anyway, you gave me a good place to start my research so thanks!

cummings66
08-13-2007, 11:47
Glad to be of service, I knew the tank types you wanted are available. I've never seen them, but they can be had.

ScubaBoy
10-14-2007, 18:42
I don't understand how a tank can be made of carbon fiber. While carbon fiber has many properties to make things lighter and stronger, I don't understand what process you could use to make a carbon fiber tank that would hold as much pressure as alu or steel.

fire diver
10-14-2007, 19:43
The carbon fiber is wrapped around a thinner aluminum tank.

RoadRacer1978
10-14-2007, 19:51
Found a 106 online for sale. As you all imagined the price is crazy high.
$459.99

http://www.divetrainers.com/Tanks-Luxfer_ALUM_106_LIMITED_White_Aluminum_Tank.html

BobbyWombat
10-14-2007, 21:44
Really only useful if you have a long way to carry it on land, I think. Doesn't really make a difference in the water.

danielh03
10-17-2007, 02:44
The thing with carbon fiber tanks is they usually wont pass a hydro after 10-12 years. I had a ton of info on them when I did fire fighting, maybe I can find it again.

fire diver
10-17-2007, 08:17
It's not that they WON'T pass hydro, it's that they can no longer be hyrdo'ed. They have a 12 or 15 life span. After that, they are required to be destroyed. They also have to be hydro'ed every 3 years IIRC.

FD

Bring the Payne
10-17-2007, 12:17
This might be a dumb question but what psi do fire fighters usually fill to their tanks to? I ask because wouldnt being in/around/near fire cause the pressure to build up a lot in the tanks? Got to thinking about that yesterday and Im a little curious as to the setup you guys use?

fire diver
10-17-2007, 12:26
depends entirely on the system in use. Our old system was 2216 PSI in AL bottles. Our new system is 4500 in carbon fiber composite tanks.

As for the heat, the tanks may warm up a couple hundred degrees, but not enough to worry about. They don't get anywhere near test pressure.

Actually, I've never seen my own tank go above the fill rating. If you are in that hot of an environment, you are breathing from your reg and lowering the pressure.

Bring the Payne
10-17-2007, 12:28
depends entirely on the system in use. Our old system was 2216 PSI in AL bottles. Our new system is 4500 in carbon fiber composite tanks.

As for the heat, the tanks may warm up a couple hundred degrees, but not enough to worry about. They don't get anywhere near test pressure.

Actually, I've never seen my own tank go above the fill rating. If you are in that hot of an environment, you are breathing from your reg and lowering the pressure.

Hmm that's interesting. I guess the heat doesn't affect the pressure as much as I thought....or at all really.

cummings66
10-17-2007, 13:28
Found a 106 online for sale. As you all imagined the price is crazy high.
$459.99

http://www.divetrainers.com/Tanks-Luxfer_ALUM_106_LIMITED_White_Aluminum_Tank.html

Except this is an Al tank and not the composite version. It's got to be much higher in price me thinks.

danielh03
10-17-2007, 15:22
depends entirely on the system in use. Our old system was 2216 PSI in AL bottles. Our new system is 4500 in carbon fiber composite tanks.

As for the heat, the tanks may warm up a couple hundred degrees, but not enough to worry about. They don't get anywhere near test pressure.

Actually, I've never seen my own tank go above the fill rating. If you are in that hot of an environment, you are breathing from your reg and lowering the pressure.

You were correct on the tanks not being hydrod after 12 years. I had misread my info on them! We didn't have ours long before I went to rescue and we very rarely use SCBA so we have the old steel tanks. Really sucks after your used carbon! Sorry about the mix up lol

Bring the Payne
10-17-2007, 16:26
If the carbon tanks are that much lighter I would think it would be worth spending 500 on a new tank every 12 years.

Jipps
10-22-2007, 18:28
i think the carbon is a good idea, but its expensive and i doubt u can get many dive shops to fill them, at my place our banks only go up to 4000. My boss would shoot me if i filled them any higher....mainly because that would mean i would have to change settings on the compressor.