Want to buy my own tank, but I know very little...need advice!

[uncfnp]

I too have been searching for new tanks. After researching and taking into consideration the advice I have received from SB, I have decided to rent a few different sizes of tanks and make sure i'm comfortable with what I buy and not wind up with something that is not practical for me. With that said, the next tanks I'm renting are gonna be hp steel 100's. On paper, they seem to be what i'm looking for. I run across this info, maybe it will help you out some.

Steel Tanks - Steel has a higher density rate than aluminum, which allows the tank to be negatively buoyant when your dive is completed. Steel tanks are available either in high pressure (HP) or low pressure (LP). High pressure tanks are smaller and contain a higher volume of air, and also require a regulator set up for DIN. A HP 100 is slightly smaller than an AL 80. LP tanks are much easier to fill, but are also quite large for the volume of air that they hold.

The difference between Pressure & Volume - It should be noted that the pressure of a tank is not a measure of the size or volume of a tank. For example, most aluminum tanks, from the smallest 6 cuft pony bottle to an 80 cuft tank, have a fill pressure of 3000 psi. For a 6 cuft bottle, this means at 3000 psi the tank contains 6 cuft of air. For an 80 cuft bottle this means at 3000 psi the tank contains 80 cuft of air. Tanks come in a variety of combinations of volumes and fill pressures but the cubic foot (cuft) volume is the measure of how much air a tank holds.

Valves - A K-valve, which comes on all aluminum tanks and low pressure steel tanks, do nothing other than release or stop the flow of air from the cylinder.

DIN valve - These valves are used on all high pressure tanks - 3300 PSI and above. Regulators used on HP tanks require that your regulator be converted to DIN.

While DIN are consider preferable by some. I dive with HP tanks with yoke and have had no issues. I do crack my tank slowly.

 

[diver 85]

Not always. I've got a 130 cf HP steel tank with a roughly 3400 PSI rated fill pressure and I only use yoke regulators.

Richard.

Same here-----dive HP120s all the time with(any of) my yoke 1st stages..........

 

[Peter69_56]

I would recommend anyone buying new cylinders get them with a DIN with yoke insert. In this way it makes the cylinder easier to sell later as the market then includes Tech divers (who generally prefer DIN), also allows the diver to progress to Tech and have DIN cylinders. In OZ anyway I don't believe it makes a difference if the cylinder is HP or LP, we don't talk about cylinders in this way other than 300 BAR (4350 PSI) and the others 232 BAR (3360 PSI) and below. Its sort of 300 BAR or normal. Most cylinders seem to come now with DIN and an insert so they are universal.

 

[lowviz]

The standard yoke adapter won't fit around a 300 bar DIN valve. Stick with the lower rating so that you have the option of using an insert....

 

[Peter69_56]

The standard yoke adapter won't fit around a 300 bar DIN valve. Stick with the lower rating so that you have the option of using an insert....

I don't think the 300 BAR valves come with an insert do they? So on that basis if you have K reg then 232 BAR DIN is the only one to buy with K valve insert (which in OZ is the standard valve with Faber or aluminium cylinders excluding 300 BAR cylinders).

Here I think if you buy 300 BAR its for a specific duty and usually Tech. Most buy the 232 BAR.

 

[tomfcrist]

I've used 232bar din manifolds on my doubles for as long as I can remember. Even with wreck fills, I have never needed a 300bar manifold. The good thing about 300 bar is that only one type of din regulator can be used with it(300bar) but with a 232 bar manifold, any din reg will work just fine....it's really a matter of preference. I have also used yoke regs on hp tanks and although I never had an issue with it, I understand the physics behind din, and prefer to go that route.

 

[lowviz]

I don't think the 300 BAR valves come with an insert do they? ...//...

No, they do not. Most divers wanting to convert to yoke only find this out after the purchase. -only reason I posted.

...//... Most buy the 232 BAR.

So do I, for both tech and rec. Never heard of a 2xx BAR valve failing (at the threads) due to an HP fill.

Just bought a new 300 BAR Thermo manifold, I would have preferred a 232 but (in a rush) not to be. It is laser burned "AIR ONLY U14", my LDS laughs every time they fill it with whatever mix I need. -and yes, they O2 cleaned the manifold...

---------- Post added July 13th, 2013 at 08:36 PM ----------

...//... The good thing about 300 bar is that only one type of din regulator can be used with it(300bar) but with a 232 bar manifold, any din reg will work just fine ...//...

Yeah, there is a good point here. Buy a 300 BAR primary reg and all 232 BAR valves. -will never have a problem.