Just picked up a Steel 72

[kawasakign]

I just got a used Steel 72 for a good price and it included a brand new hydro and vip. I have a few questions about it. Its an older thank and stamped rating with 2250. Does anyone have any specifications for this tank? Only steel 72s I can find say a service rating of 3000.
So am I right in saying it holds 72 ft^3 of air at 2250? or at 3000psi?
Its a 6.9inch ish diamter and 24inch ish height tank.

 

[Lead_carrier]

I just got a used Steel 72 for a good price and it included a brand new hydro and vip. I have a few questions about it. Its an older thank and stamped rating with 2250. Does anyone have any specifications for this tank? Only steel 72s I can find say a service rating of 3000.
So am I right in saying it holds 72 ft^3 of air at 2250? or at 3000psi?
Its a 6.9inch ish diamter and 24inch ish height tank.

If it is stamped 2250, then you get 72 cf at 2250.

 

[spectrum]

If it is stamped 2250, then you get 72 cf at 2250.

Actually if it is a 72 and stamped 2250 you will only have 72 CF of air if it had the + renewed at hydro time. In that case it would be filled to 2475 the hit the advertised capacity of 72 CF.

 

[DA Aquamaster]

At the 2250 psi service pressure you get 64.7 cu ft. At 2475 psi (10% overfill) you get 71.2 cu ft.

Bouyancy wise, they are about 1 lb negative when empty and about 5.5 lbs negative when full. That said, teel 72's were made by several companies and there is some variation between them.

 

[texdiveguy]

I to have one, and it makes a super stage bottom gas bottle or O2 deco bottle!!

 

[kawasakign]

I to have one, and it makes a super stage bottom gas bottle or O2 deco bottle!!

Actually that is exactly what I thought might be a good use for this one. I figure it will be a good steel tank for single tank dives in the quarry (as that will be where my primary dives will be for now). Then when I get more into tech it can be a good tank for deco. But first I have to learn how to use my double 95s I just got before I even think about deco. (Got those because it was too good a deal to pass up and figure what the hell, they can sit in the closet until I get the training to use them).

 

[Hoosier]

I to have one, and it makes a super stage bottom gas bottle or O2 deco bottle!!

You don't think you are overweighted. In my case, the heavy double is already overweighted with an AL plate, so I am not sure if it is a right move....

 

[DA Aquamaster]

I agree...a steel 72 is a bit heavy for deco or stage bottle use when you are already negatively challenged with steel doubles.

Plus an AL 80 actually works a lot better for travel gas or for a large deco bottle as they tend to become bouyant at the base as they empty so they streamline very well when properly rigged.

 

[texdiveguy]

You don't think you are overweighted. In my case, the heavy double is already overweighted with an AL plate, so I am not sure if it is a right move....

Absolutaly not..... a st 72 is a nice balance for a stage bottle....I use Al 80s and Al 50's as well for deco bottles. I find that the divers whom question the use of steel 72's for use as stage bottles or O2 deco bottles just have for the most part never used one themselves....not saying you my not have used one and just found it not to your liking....but 9 out of 10 are talking from what they have 'heard',,,,that happens alot particularly on these boards--lol. There is not an issue when rigged with an Al 80 and a St 72 at the same time. I also don't use the smaller Al 40 alot of divers use....just my personal pick. St 72s are seen quit often in o/w diving on wrecks....in rough waters they offer an advantage on 10-20ft. deco stops. In the water they swim very well and I have had no trouble with trim.

 

[texdiveguy]

I agree...a steel 72 is a bit heavy for deco or stage bottle use when you are already negatively challenged with steel doubles.

Plus an AL 80 actually works a lot better for travel gas or for a large deco bottle as they tend to become bouyant at the base as they empty so they streamline very well when properly rigged.

I disagree on the statement they are to heavy,,,that is just not true. I agree that Al 80's
make fine deco bottles and that they do store well. But for me the st. 72 is just right for a bottom gas stage and is a great companion on shallow O2 decoing. But I also don't carry a broken bladed steak knife as a cutting tool and I do wear a redundant wing while diving doubles in a wet suit....we each must pick and select gear to do the job for us.