Why are 300 bar tanks not available in North America?

[crunchiespg]

What's the reason that 300 bar tanks like this one. Faber 12 Ltr 300 Bar Cylinder | Simply Scuba UK are not available in North America?
Seems like a no brainer. More air for same size tank no?

 

[BRT]

One reason is that it is hard enough to get good fills in 3500 psi cylinders.

 

[gr8jab]

It's hard to get a good plate of spaghetti here, but that doesn't mean they don't sell noodles.

I can hear it now, "Half of those stupid Americans can't run a vacuum cleaner, let alone a SCUBA compressor. Why bother to sell them our tanks anyway?"

Sorry - I'm not trying to be rude, just funny.

But seriously, is it easier to get 4300psi fills in other places around the world? Are we so different that they wouldn't bother to sell that tank here? Maybe so. Of this, I'm ignorant. It seems a little silly upon initial consideration.

 

[NAM001]

I cant imagine anyone wanting a 300 bar tank. I have lifted a 300 bar tank about the size of a al30 and it weighs a ton.

 

[MikkelBC]

I am under the impression (but don't know for sure) that the yoke connector, which is common in the US, is not rated for 300 bar. That might affect the availability of the tanks.

Even though the tanks are heavier for the same internal uncompressed volume, their displacement is also smaller, so the total weight you end up carrying, including lead, could very well be smaller.

 

[NAM001]

That affects buoyancy . i picked up a doubles rig that was probably a pair of tanks equal to a pair of al30's and it was i think a good 70# or better. Probably heavire than a doubles set of 104's. look at huron specs at the i think hieser 300 bar tank and look at the weight. 87#. and if you scale it down toa 3000 psi tank then the capacity would be about 120. NOw look at the pst e7 120 38#...... 2.5 times teh weight for 50% more air. And look at that buoyancy. -45 to -60#.

Heiser 190

4400

190

8.03

31.3

87

-46.86

-62.3

PST E7-120

3442 PSI

120

7.25

28.25

38

0

-10.5

I am under the impression (but don't know for sure) that the yoke connector, which is common in the US, is not rated for 300 bar. That might affect the availability of the tanks.

Even though the tanks are heavier for the same internal uncompressed volume, their displacement is also smaller, so the total weight you end up carrying, including lead, could very well be smaller.

 

[Yoyodyne-88]

It's an interesting observation that some tanks we use in the USA are the same as Europeans use, but they are rated for higher pressure in Europe.

 

[Storker]

But seriously, is it easier to get 4300psi fills in other places around the world?

In this part of the world, 300 bar fills are about as easy to get as 200 or 232 bar fills, due to the widespread use of 300 bar tanks.

I cant imagine anyone wanting a 300 bar tank.

I have several 10L 300 bar tanks in my attic. I prefer those over my 15L 200 bar, because they weigh about the same, has the same nominal capacity (not accounting for the 5-10% capacity loss due to compressibility effects) and are more negative due to the smaller volume. That means I need to carry less weight, and my rig is actually lighter.

I have lifted a 300 bar tank about the size of a al30 and it weighs a ton.

Dang. What kind of tank was that? Both 10L and 12L 300 bar steel singles are quite popular around here, in fact the 10L 300 bar has become the current standard rec tank that the shops sell to newbies. A 15L 300 bar, though, is a b*tch to lift and handle (I have one of those as well), so if you want - or need - that much air, you'll probably be better off with a set of small doubles.

I am under the impression (but don't know for sure) that the yoke connector, which is common in the US, is not rated for 300 bar.

If you want 300 bar, you need a DIN connector.

 

[Scared Silly]

It's an interesting observation that some tanks we use in the USA are the same as Europeans use, but they are rated for higher pressure in Europe.

No they are not. That is a myth they have the same form factor but are made of different alloys.

 

[NAM001]

I have heard that statement before and said it also. some replies i have got are. And they all make sence.

US has a 4:1 safety factor and non US uses 2 and 3 to 1. a 3000 (steel)psi tank in the us is a 4000# tank in other nations. US biggest user of AL tanks???
(steel tanks are the norm outside of the us.) perhaps why shops cant fill non dot tanks to stamped pressure. (safety factor)
the valve is a much lighter valve and a lower presure valve. 2.5# over seas and 1.5 in the us. how ever that figures in. (perhaps the weakest link in the air path)
the tanks made for over seas are made with a different alloy than the us tanks. Hmmmm.

It's an interesting observation that some tanks we use in the USA are the same as Europeans use, but they are rated for higher pressure in Europe.