Help me read my steel tank, is it still good?

[DivingDavid]

I finally (after years of wishing) recieved my OW in August of 07 and am getting my stuff together. I pulled down a scuba air tank I've had in the attic for 7 years (okay I'm a bit of a pack rat) hoping it wasn't an aluminum tank. I've always asumed it was and after reading up on old AL tanks I am soooo happy that it's STEEL!! First I checked it with a magnet! Then I (not seeing the 3AL on the tank) pulled out my OW manuel and figured out that it indeed is steel!

Back in '96 I saw this tank sitting on a curb in the trash, grabed it, took it to a dive shop who charged me $25 to tumble, hydro,vis inspect and refill. I guess they assumed I was certified. Anyway about a year later I heard this loud hissing in the garage and have learned that was probably the burst disk doing its thing. So it has layed in my attic in Texas since 2000, valve closed, blown disk, and no pressure.

Now the questions:

I'm all for getting it visually inspected, with rust being a possibility from humidity and changing temperatures. But is there any way to get around paying for another hydro test, or do I have to, to get another date stamp on the neck? I mean the tag from the last one is still on the valve.

The other question is What Do All These Numbers Mean? It doesn't follow the format in my book. I'ts a U S Divers tank with Cayman Island stickers all over it. On sticker says " Bob Soto's Diving LTD Grand Cayman, BWI" with this turtle with a snorkle and mask on. The numbers are:

ICC3AA2250 under that is K6746 under that is USD
under that is 4(O with a small L in it)65+

on the other side is U S DIVERS CO. and under that is 9(O with a small R in it)78

then between them is my 9(small c over a small 19)96 from when I had it tested.

It has a orange handled VOIT brand 'K' valve with D06647 stamped in it
and the tank must be galvanized as it is silver (not painted) and has no rust.

Alright ... so could someone tell me if I can still be happy and how much is it worth?

Thanks ~ David

 

[herman]

The tank is steel -3AA, most likely a 72cf. ICC is the Interstate Commerce Commission, the predecessor of DOT. It's rated pressure is 2250 psi (did the LDS put 3000 in it? that may have been to reason the burst disk did it's thing). The 4xx65+ means it was first hydroed (made) in April of 65. The + means it was rated to be overfilled by 10% during the ORIGINAL hydro date. The 9xx78, 9xx96 means it was hydroed in Sept of 78 and again in 96. The letters/stuff between the dates is the seal (unique ID) of the hydro facility.

If it were mine I would have it quick vised (look inside and see if still looks OK) then a real vis, hydro and use it. Otherwise find a vintage diver to give it to.

 

[divinginn]

even if there is some rust in there it can be tumbled out,open it up look at it to make sure it is not shot and get a new hydro. they are great tanks for shallow dives esp. if you can get some good fills on them.I have two of them.

 

[rob from nova scotia]

even if there is some rust in there it can be tumbled out,open it up look at it to make sure it is not shot and get a new hydro. they are great tanks for shallow dives esp. if you can get some good fills on them.I have two of them.

I would say make a mail box out of it or give it away , cause a 72 as you guessed has less air in it than an 80 so the dive buudy of yours if hes got a 72 wondeful if he has an 80 hes going to pissed at you calling the dive cause your always short on air, also the bc strap will always have to be changed from the 72 from an 80....and the cost will be the same as an 80 fill, so now you have 3 negatives on keeping the 72......enjoy

 

[Hallmac]

There is nothing wrong with having a 72 cf tank, the cost of a Hydro around here is under 30 bucks. I can dive a 72 and still have air while many of the divers in our group have sucked 95's dry. Have it serviced and enjoy.

 

[Jimmer]

I would say make a mail box out of it or give it away , cause a 72 as you guessed has less air in it than an 80 so the dive buudy of yours if hes got a 72 wondeful if he has an 80 hes going to pissed at you calling the dive cause your always short on air, also the bc strap will always have to be changed from the 72 from an 80....and the cost will be the same as an 80 fill, so now you have 3 negatives on keeping the 72......enjoy

An al80 is 77 cubic feet. You're going to have a fit over a difference of 5 cubic feet? Depending who I'm diving with, I can easily outlast a guy with an al80 if his breathing rate is even a little worse than mine.

 

[scubadale]

Now the questions:

I'm all for getting it visually inspected, with rust being a possibility from humidity and changing temperatures. But is there any way to get around paying for another hydro test, or do I have to, to get another date stamp on the neck? I mean the tag from the last one is still on the valve.

Alright ... so could someone tell me if I can still be happy and how much is it worth?

Thanks ~ David

Your question in regards to what the numbers mean has been answered.

As for the above two: Yes you will have to get a new hydro. DOT requirements every 5 years. So even if you could convince someone to fill the tank based on the tag still being on the valve, the tag would be gone after one use and then you would need a hydro.

As for how much is it worth you will have to determine that. You potentially have a good steel tank with a capacity of 72cu.

If your around Palestine I would be happy to give it a glance and let you know if its worth pursuing or not. PM me if needed.

 

[Jim Lapenta]

That is one of the least intelligent suggestions I've heard. A steel 72 is one of the finest tanks there is. I have 4 of them. 2 from 55& 56 respectively. The others are from 73 and are doubled up. I have no problems using my 72 on dives with others in al80's(which by the way around here after they are 15 years old are considered done and most places will no longer hydro them). The size of the tank really only comes into play when divers SAC rates are so close that the extra 4 or 5 cu ft is going to make a big deal. Most times it does not.

I'll put me and one of my 72's up against anybody with an al80 any time on a similar profile and if it's less than 50 ft be guaranteed at least an hour or more of bottom time. I normally get around 2 hours out of one doing checkout dives with students where the max depth is 30 ft or less.

Your SAC rate determines how long you can get out of a tank. And a steel 72 with a good disc pumped to 2800 or so which we routinely do will give you 81.4 cu ft as opposed to the al80 which at 3000 incidentally is only 77 cuft. In fact my doubles are routinely filled to 3000 for most outings with no ill effects. I also see many new divers who think getting an hour out of an al80 on a 40 ft reef is doing good:no. It's not. When doing reef dives in the keys with a 40 ft max depth I usually come back after an hour with 1600-2000 psi depending on current, how much I work at it, if I'm taking pics and using little air, while I see others( mostly what I call underwater tourists) barely make it back with the 500 the op wants. I've even used the same tank for both dives.

But maybe you should get rid of it as we all know how hard it is to take up the extra inch in a tank strap.

Along with the increased capacity is the better buoyancy characteristics of the steel tank and the longer lifespan. I'd spring for the vis and if needed a tumble and new hydro. For maybe, what, 30-50 bucks you've got a tank that with proper care will most likely outlive you.

If you don't want to do it send me your addy and I'll pay shipping for you to send it to me where it'll get a good home a ALOT of use.

 

[spectrum]

I would say make a mail box out of it or give it away , cause a 72 as you guessed has less air in it than an 80 so the dive buudy of yours if hes got a 72 wondeful if he has an 80 hes going to pissed at you calling the dive cause your always short on air, also the bc strap will always have to be changed from the 72 from an 80....and the cost will be the same as an 80 fill, so now you have 3 negatives on keeping the 72......enjoy

Who says he's always going to be short on air? 72 CF is more than enough for my typical 1 hour shore dive. I happen to have only one 72 but my steel Hp 80's almost always come home with well over 1000 PSI. A fill is a dive and resetting my cam-bands is pretty trivial.

Maybe you have no use for the cylinder but plenty of folks can make very good use of it.

Pete

 

[DivingDavid]

You all have been great! I've done some digging around on the net while waiting on responses and you have pretty much confirmed what I found. I can surmise that the K6746 # is the serial # or similar. Thanks Herman

I would think that so few hydro stamps mean that it has hardly been used, compared to how many stamps it would have if regularly used. 78 + 5 years would mean it would have last legaly been filled in 83, aside from my fill in 96. That seems good!

And as my air consumption was lower than most everyone in my scuba class, except the instructors, I should do just fine on 72. I've done alot of snorkeling.

I think the expense getting it checked and fixed up is well worth it.

Thanks~David