Tank size

[BoltSnap]

According to the table above, the 12L/232B can be filled to 250Bar and will hold the same volume of gas as the 10L/300B tanks so no need for the 10L/300B I think. But the 12L/300B is a different story however. I don't know about the weight properties for the 12L/300B vs. 15L/232B but I believe that the 12L/300B still weighs less but not certain. I had a friend who used a double 12L/300B that appeared to me to weigh less than a double 15L setup.

The 12L/300B tanks are the long type not the short type. The short 12L/232B are great tanks for when you want to dive singles and take lead of your belt and the dive profile doesn't warrant a 15L/232B tank. We use them in our dive school as standard tanks for training and they are great.

 

[archer1960]

...

Size is the other non linear factor driving tank weight. The larger the diameter and the longer the straight section of the tank, the higher the hoop stress, and the thicker the walls need to be to resist those stresses. Consequently, fatter and/or longer tanks are disproportionately heavier than thinner, shorter tanks.

That's true for diameter, but not for length. Larger diameter tanks at the same pressure need thicker walls. Longer tanks of the same diameter do not. That's why high-pressure cylinders are pretty much always long and skinny.

 

[Carl T]

Wow, that's a lot of info to take in! my recent purchase (ebay MR52) have Din 300 fitting. I'm happy to ditch the 15 litre 232 A clamp but want a 232 din fitting with A clamp option as 300 bar isn't reliable. If I could get a 232 bar din for the MR52 and a 232 bar din/ A clamp tank valve 12 litre I would be sorted. I definitely prefer the Din fitting for all the known reasons but the Mares site only shows 232 A clamp or 300 din!!
Thanks for every ones response, not in the dark after all.

 

[tbone1004]

300 bar din regulators should be backwards compatible to 200 bar and 232bar valves. The fill whips in europe are generally not backwards compatible due to safety reasons, but the regulators are.

 

[Patoux01]

You seem to be mixing things up a bit. (at least, so it feels)
300b (necessarily DIN) regs fit on 300b, 232b valves and on yoke with an adapter
200b din regs fit only on 200b valves (232, same thing) and on yoke with an adapter
Yoke only exists for 200b (232), and don't exist for more than that.

Therefore, regs are not typically sold as 232b din, but only as 300b (because the 300 fits all).


Most (if not all) 230b DIN tank valve can be changed in a yoke outlet very easily. Many yoke valves are actually just that, DIN with an adapter. (see picture)

Hope this helps clarifying your stuff out.

 

[Carl T]

Thank you!!! yes it does. One further question, I have a 12 litre 232 bar A clamp/din 232 valve. Is it safe to fit my 300 bar Mare MR52 300 bar din reg to it? I can't get reliable 300 bar so always assume 232.

 

[tbone1004]

i think you're using reliable in the wrong context here. Fitting 300bar din regs to 200/232bar din valves is not a safety concern and most companies in the US are only supplying the 200bar din valves because the 300bar din valves are not necessary

 

[Gareth J]

From memory, the 300 bar fitting is 7 threads long (7 complete turns). The 200 (232) bar fittings are 5 threads long (5 complete turns).

A 300 bar first stage (7 thread's) will fit into a 232 bar tank DIN valve. There is no risk!
A 232 bar first stage (5 thread's) will not screw home into a 300 bar DIN tank valve (7 thread's). The reason for this is if a 232 bar second stage was connected to a 300 bar cylinder there is a risk of the first stage failing. By having insufficient threads to screw home, it never seals and the air 'leaks' pass the second stage.

Edited to clarify statement

 

[tbone1004]

there is no risk of it failing. It just won't seat so as soon as you open the valve it will start bleeding out of the small hole in the side of the valve, pretty idiot proof