Spun composit cylinders?

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deerhunter1911a1

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howdy all, i have been thinking, and i know a lot of paintballers use composite cylinders, and a lot of fire departments are going to spun composite cylinders they pump up to a massive and whopping 5000psi. does anyone know if these cylinders are available or being used for scuba? if they are small, light, and can take that much pressure, is price the only thing holding them back from popular use? thanks guys and gals!
 
howdy all, i have been thinking, and i know a lot of paintballers use composite cylinders, and a lot of fire departments are going to spun composite cylinders they pump up to a massive and whopping 5000psi. does anyone know if these cylinders are available or being used for scuba? if they are small, light, and can take that much pressure, is price the only thing holding them back from popular use? thanks guys and gals!


I asked that same question the other day @ a local FD(that's where I get my air) & we thought it might wind up being too + bouyant???...
 
Are they really that much smaller and lighter? I looked at a comparison chart not to long ago and I didn't think the weight/size difference was significant but the list did not contain prices so it is hard to compare. I have heard some suggest that the new tanks might not hold up that well to the banging and beating that normal cylinders do. It will be interesting to see what those in the know have to say about the issue.
 
Along with the durability and weight issues how many places can fill a tank to 5000 PSI?
 
Luxfer has a hoop wrapped composite cylinder called the S106W. It is essentially their S080 with a composite wrap and a 4350 psi service pressure boosting the capacity to 105.2 cu ft. It is .1" larger in diameter and about 2.5 lbs heavier than an AL 80.

The bad news is that hoop wrapped tanks have a 15 year life span and if you damage the outer coating and expose or damage the composite wrap, the tank is basically toast. Composite wraps work ok for SCBA cylinders for fire departments but they are less than ideal for scuba tanks.

Weightwise, the 33.8 lb S106W compares very well to the larger and heavier 41 lb S100, but is .8 lbs heavier than a much smaller in over all size PST or Worthington 100 cu st steel tanks that will be much more durable and last longer than 15 years.

If you want to be the only kid on the block to own one, go for it - and good luck finding a 4350 psi fill. If you want a practical lightweight 100 cu ft tank, go with a 3442 psi Worthington X7-100 steel tank.
 
Light is not a huge advantage in a sport whose participants strap lead weights to themselves. 5000 psi would be nice though.
 
Light is not a huge advantage in a sport whose participants strap lead weights to themselves. 5000 psi would be nice though.

That might be true but getting much better buoyancy characteristics (difference of 5.6 pounds) in a more compact package (2.1 inches shorter) and a well tested technology is much more worthwhile.

There is also the issue of determining whether regulators will handle the increased pressure differential between 3442 and 4350 PSI.
 
Composite cylinders are used often in aviation for oxygen and nitrogen but they have many limitations. True composite cylinders are very light in weight. They are not all that durable either.

N
 
...so let me see, lets buy this expensive composite cylinder, rated @ 106 cu. ft. @ 4350 psi, fill it to the typical / available 3000 psi , and we end up with 73 cu. ft. ??? !!!!

...somehow I fail to see the point in having this tank.....
 

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