Why no carbon fiber tanks?

[Bob DBF]

Fair enough! No paint cover is perfect!

Galvanized is closer to perfect.

 

[Celt]

http://www.carbondive.com

 

[211ratsbud]

I see a lot of carbondive tanks in action.. of all sizes some don't need weight added some do. Rated at safety factor like 3 to 1 with out the carbon wrapping.

 

[Misfit12]

Galvonic coupling is a thing I've learned about. It still seems like there has to be damage to the outside of the tank for especially salt water to get in, and then it actually has to corrode bad enough to fail.

 

[MikeHoncho]

There is some mis information here. Carbon fiber wrapped tanks are very robust. We have been using them in the fire service for over 30 years with increasingly higher pressures. Typical modern bottles are 4650psi and take an absolute beating. A downside is required hydro every 3 years instead of five. in 27+ years I have only seen bottles taken out of service from damage due to bottles sliding across pavement having significant abrasion damage to the wrap and significant thermal damage to the wrap. A real truth is their buoyancy. A firefighter will float in full gear with scba on even after their bunker gear is fully saturated. Now I guess an argument could be that a Scuba carbon wrap version tank isn’t built to the same NFPA SCBA bottle.

 

[OMyMyOHellYes]

I see a lot of carbondive tanks in action.. of all sizes some don't need weight added some do. Rated at safety factor like 3 to 1 with out the carbon wrapping.

In the US? Are they DOT approved?

 

[Misfit12]

There is some mis information here. Carbon fiber wrapped tanks are very robust. We have been using them in the fire service for over 30 years with increasingly higher pressures. Typical modern bottles are 4650psi and take an absolute beating. A downside is required hydro every 3 years instead of five. in 27+ years I have only seen bottles taken out of service from damage due to bottles sliding across pavement having significant abrasion damage to the wrap and significant thermal damage to the wrap. A real truth is their buoyancy. A firefighter will float in full gear with scba on even after their bunker gear is fully saturated. Now I guess an argument could be that a Scuba carbon wrap version tank isn’t built to the same NFPA SCBA bottle.

Seems you are referring more to SCBA than SCUBA. What about using them for diving?

 

[beldridg]

In the US? Are they DOT approved?

Yes, I have two of them for rebreather bailout tanks. They are not DOT approved. Because they are bailout tanks, I don't need to get them filled very often. Here is my writeup on them:

Carbon Fiber Twins (or, maximizing bailout gas efficiency)

(NB: experienced technical rebreather divers might find this post “boring” while beginning technical divers might find it interesting and provide you something possibly new to think abo…

wreckedinmyrevo.com

- brett

 

[MikeHoncho]

Seems you are referring more to SCBA than SCUBA. What about using them for diving?

Make no mistake I am but the technology is there. The fire service rates bottles by minutes (which is about useless) a typical bottle is a 30 minute bottle with about 45 cubic feet at 4600psi. You can get 60 minute bottles but all of them are about 3 times the cost of steel and require hydros at 3 years. You are starting to see compressed gas tube trailers and intermodal shaving larger tanks that are carbon wrapped. These have around 6000 psi.

 

[Misfit12]

Make no mistake I am but the technology is there. The fire service rates bottles by minutes (which is about useless) a typical bottle is a 30 minute bottle with about 45 cubic feet at 4600psi. You can get 60 minute bottles but all of them are about 3 times the cost of steel and require hydros at 3 years. You are starting to see compressed gas tube trailers and intermodal shaving larger tanks that are carbon wrapped. These have around 6000 psi.

How do you get a 6000 psi fill? Most scuba shops i know of can fill to the high 3000's at best. Do fire departments just have different compressors?