Manufacturing Materials for SCUBA

[Dr. Vinny]

High tech manufacturers have been using Carbon materials for strength and durability for sometime now. Our EMT folk have engaged with a gas cylinder, SCBA, but I find the recreation industry appears to have ignored this material.

Now it's alleged that the manufacturing environment is going be booming. Is there any plan to certify a "SCUBA" tank made from these materials or are our Chinese friends going to maintain control of this product.

 

[flyboy08]

I fly in mostly composite made aircraft these days! I would like a carbon fiber tank that weighs in filled at a few pounds! These alum and steel tanks are so 1980ish!

 

[redacted]

For most applications, why would divers want to remove 20 lb or more of aluminum or steel just to add it back to their rig with lead?

 

[Damselfish]

They're sometimes used in firefighting and other applications that don't require sinking the tank because the lighter weight is actually helpful. (If you took advantage of the higher pressures that are possible, you'll have a smaller tank that is not quite as buoyant, but try finding a dive shop that could actually fill it to capacity.) I think durability in the typical dive environment is also an issue.

 

[crookshanky]

High tech manufacturers have been using Carbon materials for strength and durability for sometime now. Our EMT folk have engaged with a gas cylinder, SCBA, but I find the recreation industry appears to have ignored this material.

Now it's alleged that the manufacturing environment is going be booming. Is there any plan to certify a "SCUBA" tank made from these materials or are our Chinese friends going to maintain control of this product.

Cost, service life, durability, and station fill pressure limitations seem to be the reasons why they have not become popular. It would be great to have that extra gas in the same size envelope. Luxfor's specs show their hoop-wrap is very similar in buoyancy characteristics to their Al80's (with 50% more capacity).

For most applications, why would divers want to remove 20 lb or more of aluminum or steel just to add it back to their rig with lead?

It would be great for applications such as sidemount. I would rather have the weight in a pouch right next to my body then on the cylinders (especially when having to remove and maneuver them during the dive).

 

[redacted]

It would be great for applications such as sidemount. I would rather have the weight in a pouch right next to my body then on the cylinders (especially when having to remove and maneuver them during the dive).

how would you go about gettng in and out of the water with a pair of 20 lb buoyant balloons and 40 lb of lead?

 

[Rred]

Rashly assuming you could use an FRP tank at twice the pressure of a metal tank, that would allow it to have half the volume, which should make for less weight overall. But it all comes back to money. No shops are going to buy 10,000 psi compressors. (That's what the NASA composite tanks used decades ago.) And the DOT has only certified FRP tanks for limited use, more frequent inspection, and shorter lifetimes. So it all comes back to money. FRP tanks may make sense to some users, but who wants to pay what they are going to sell for? And what it will cost to service and fill them, especially if they are a higher psi rating?

And of course, everyone in the "tank" business already has metal-working machinery, they'd need to invest in all new systems to make FRP tanks.

I don't see how a profit can be made from them, so who will market them? Except to a few niche markets, like NASA.

 

[Trailboss123]

For most applications, why would divers want to remove 20 lb or more of aluminum or steel just to add it back to their rig with lead?

The amount of lead that anyone requires to dive properly is dependent on a number of factors (in addition to the type and size of tank that one uses.) The "physical" weight of a tank does not equal "buoyancy" weight. Attached is some valuable info on tank buoyancy characteristics. Also, in case anyone is really interested or curious, every 10 lbs in body fat will cost you an additional 1lb in lead to compensate- don't get me started on bone density-- LOL

 

[redacted]

The amount of lead that anyone requires to dive properly is dependent on a number of factors (in addition to the type and size of tank that one uses.) The "physical" weight of a tank does not equal "buoyancy" weight. Attached is some valuable info on tank buoyancy characteristics. Also, in case anyone is really interested or curious, every 10 lbs in body fat will cost you an additional 1lb in lead to compensate- don't get me started on bone density-- LOL

Yet some rought estimates are possible. How much lead do you figure it would take to offset the buoyancy of 11 to 15 liters of air?

 

[tbone1004]

High tech manufacturers have been using Carbon materials for strength and durability for sometime now. Our EMT folk have engaged with a gas cylinder, SCBA, but I find the recreation industry appears to have ignored this material.

Now it's alleged that the manufacturing environment is going be booming. Is there any plan to certify a "SCUBA" tank made from these materials or are our Chinese friends going to maintain control of this product.

there are far more serious concerns with these tanks in marine use than the cost of compressors and storage systems which goes up about 4 fold when you get to those kinds of pressures. As one who has done design work on composite cylinders, the biggest concern is any damage in the resin can cause water ingress into the layers themselves and cause damage that will not be shown in hydro so long term use is not going to be good