Decommissioning my AL tanks

[John C. Ratliff]

My twin aluminum 50s have seen their last fill. I am in the process of "decommissioning" them. They will be removed from service, along with my two AL 80s that I got as a present from a friend about ten years ago. Why? They have passed their hydros and their visuals/eddie current testing. Why decommission them then? Well, I have read the Federal Register over a year ago, where the DOT was saying that these tanks had a useful life of about 35 years. I don't have that reference in front of me, but these tanks date to 1974 and 1976, respectively. That makes the older of the two 37 years old. It has had a lot of use, and spent several winters unused with pressure in them. So, they will be taken out of circulation (no offers to buy, please). The major impetus for this is the thread on Scubaboard about Rick Allen's accident:

While I don't think these tanks would do this, I don't want even the slightest chance. Here's the rundown on the marking of these 50 cubic foot tanks.

Tank #1
DOT-SP6493-3000 (with a "3AL" stamped above the "SP")
R21316 USD
Hydros: 10/74, 3/80, 3/88, 7/99, 8/04, 10/09

Tank #2
DOT-SP6498-3000
R21389
A
Hydros: 10/76, 3/88, 9/93, 7/99, 8/04, 10/09

I got these tanks from a friend/coworker of my wife's when she lost her husband to a bridge collapse accident. A portion of the bridge collapsed, and the workers were wearing harnesses for fall protection while on a scaffold. But the harness was tied off to the portion of the bridge that fell into the river. I believe two people died, including this diver who's wife my wife knew. I bought these tanks from her, as her husband had owned them and was a diver.

So they have had a long and productive life. Will I miss them? Probably not, as I have two sets for replacements. I put together the PJ jump tanks last fall, and now recently bought a set of USD twin 53s (52.8 cubic feet, according to the 1970 USD catelog). These twin 53s are a bit buoyant, but they will have some weights attached to them to counter that. I've also get two 72 cubic foot single cylinders, so I won't miss the AL 80s that I'm decommissioning.

Here are the two 80 cubic foot tanks I'm also decommissioning:

DOT-E6498-3000 (3AL stamped above the "E")
P130552 USD
Hydros: 10/76, 4/86, 10/03, 8/08

CTC/DOT-E6498-3000
P 269127 USD
Hydros: 6/80, 10/90, 8/95, 3/02, 2/07

Puff, I may do that (keep them for desplay), but they do take up some space. It is a good thought though.

I talked to the LDS about these tanks, and they feel that the best way would be to put "XXXXXXX" through the DOT information stamped at the top of the tank. Before, I have drilled some tanks (US Navy Aluminum tanks that were received by a school for welding practice, and someone wanted to try diving them, and a set of steel PJ jump tanks with damaged threads). Any ideas about which is best?

Finally, my UDS-1 has been down for over a year because of a filler hose fitting which broke. So I'm getting the UDS-1 up and running again. Yes, they are this older aluminum tank, but these have had very slight use over the years, have a different diameter, and if they pass hydro and visual/eddie current testing will be a unique set to dive. So I'm not getting rid of all my aluminum tanks, but the majority with high use are going bye-bye.


John

 

[Akimbo]

…I talked to the LDS about these tanks, and they feel that the best way would be to put "XXXXXXX" through the DOT information stamped at the top of the tank. Before, I have drilled some tanks (US Navy Aluminum tanks that were received by a school for welding practice, and someone wanted to try diving them, and a set of steel PJ jump tanks with damaged threads). Any ideas about which is best?...

Aluminum drills easy and is an absolute assurance that they will not be filled. Alternatively, they make a nice LP volume tank at the end of a shop air line. Get an old/dead valve, cut off below the valve wheel, and tap for ¼ or ½” pipe. Mount to a wall up-side-down and you don’t have to worry about water accumulation. At least you can get some safe use out of your old friends.

 

[Eric Sedletzky]

I decommissioned an aluminum 80 I had from 1987.
It was given to me out of hydro, so I got it hydro'd then VIP'd. They told me then it passed but was on the hit list. When it came up for hydro a second time during my ownership I decided to drain it and drill it. I drilled a 1/4" hole through it and sent it in for scrap.
The polished aluminum tank to the left in my avatar photo is another AL80 that was new but I sold it shortly after the product photo was taken.
I no longer own any aluminum tanks and never will again.

 

[MarineResearch]

I have a Browning 1919a4 (belt fed crew machine gun) that would love to meet your decommissioned tanks.

 

[DaleC]

John, they are pretty short anyways but... cut down short and fitted with a boot over the open bottom they would make good display mounts for a couple of doublehoses. The bottoms would make a nice set of ashtrays too (wait a minute, nobody uses ashtrays anymore). I meant to say, yoghurt covered coffee bean dishes!

 

[Kiwi303]

I have a Browning 1919a4 (belt fed crew machine gun) that would love to meet your decommissioned tanks.

With Full tanks I bet

 

[Brendon]

Cut the bottom off, feed a guitar string down thru the neck, decrease the diameter of the bottom that you cut off by 3", drill hole thru center of circle, insert wire thru drilled hole, clamp it on the old base side in such a way that the metal hanging is inside the tank, tie some hemp string to the clamp let it hang down outside the tank a foot or so... Now you have a very loud unique bell.

 

[MarineResearch]

With Full tanks I bet

Only from a distance and behind some sand bags. I had a project about 20 years ago where we impinged a flame on large propane bullets to evaluate the performance of the pressure relief valves and tank integrity. Don't tell Osama bin Laden, but large propane bullets can make quite a political statement.

 

[znolan]

cut in half lengthwise, add a hinge and a grate... BBQ!

 

[Belmont]

Only from a distance and behind some sand bags. I had a project about 20 years ago where we impinged a flame on large propane bullets to evaluate the performance of the pressure relief valves and tank integrity. Don't tell Osama bin Laden, but large propane bullets can make quite a political statement.

You would need a pretty good phone connection to talk to Osama Ben Laden now.