Steel tank help needed

[jborg]

Every metric tank discussion states it as volume times pressure though, as in “12x232” or “10x300”, so this confusion doesn’t exist in practice. The gas volume is there if you do the multiplication.

 

[Bob DBF]

Every metric tank discussion states it as volume times pressure though, as in “12x232” or “10x300”, so this confusion doesn’t exist in practice. The gas volume is there if you do the multiplication.

And yet here we are.

 

[jborg]

Well, it's not a metric tank or it would have been marked as such, not having an unknown mystery volume and 2250 psi on it. Of course, the default metric tank is the 12L 200/232 bar, so if told nothing else one might assume a "12L" tank is one of those. "12L x 2250 psi" would have been unambiguous, if weird...

 

[kelemvor]

Every metric tank discussion states it as volume times pressure though, as in “12x232” or “10x300”, so this confusion doesn’t exist in practice. The gas volume is there if you do the multiplication.

That isn't true on scubaboard. Just look up any thread where the user posts in metric. " I was on a boat that had 12l aluminieum" is how someone would post it. 12x232 might be correct, but that's now how it's commonly discussed.

 

[Coztick]

I have had the same problem here by a tank monkey that just look at the tank and assume it's a HP100. Fortunately I was waiting for the tank and saw over 3000# on the gauge and had him shut the fill down. Now I make sure the shop knows what they are filling

Often it seems that when lp steel cylinders are discussed, the practice of overfilling them is prevalent in cave country. Apparently 4000 psi is common.
It seems odd that the best trained and most safety conscious of all divers have no issue doing this.
I've also seen claims that burst pressure
Is over 7500 psi. so maybe not as scary as it sounds?
Question for those who do...
Is it common to use the same valve with just a higher burst disc?

 

[jborg]

That isn't true on scubaboard. Just look up any thread where the user posts in metric. " I was on a boat that had 12l aluminieum" is how someone would post it. 12x232 might be correct, but that's now how it's commonly discussed.

I concede that "a twelve" is by default a 12x200 since that's by far the most common tank (steel though, don't think I've ever seen a 12L alu around here) and the 12x300 is unwieldy and super unusual. A reasonable cause of confusion for the OP, since there really isn't a 12x150 in metric world, like the one they got.

 

[Bob DBF]

Often it seems that when lp steel cylinders are discussed, the practice of overfilling them is prevalent in cave country. Apparently 4000 psi is common.
It seems odd that the best trained and most safety conscious of all divers have no issue doing this.

The LP steel they normally overfill is 2400# service pressure, not 2250#. Also they have modified the burst disc for higher pressure, and the tank isn't 50+ years old. I, personally, don't overfill tanks by much, however to be honest, I was more worried a burst disc failure than a tank failure. Loose high pressure air is dangerous.

It is odd, but not my problem.

 

[DawsonDownUnder]

So just to summarise the discussion. Whilst it may technically be a 12L tank... The volume of gas that would get put in here is actually going to be a lot lower ...

 

[runsongas]

@jborg

the aluminum 100cf @ 3300 psi is close to 12 liters water volume. the standard aluminum 80cf is closer to 10.6 liters.

 

[Pressurehead]

So just to summarise the discussion. Whilst it may technically be a 12L tank... The volume of gas that would get put in here is actually going to be a lot lower ...

The steel cylinder you have is OLD , so is the valve. Where in Australia are you? There are specials on NEW cylinders and they come EANitrox ready with new Din/K valves.
I love shiny new things [ have plenty of old stuff, but!] NICE: