Dive tank permanent expiration?

[mdeboard]

I have old tanks that were originally stamped 7/90. My dive instructor told me that in the U.S. they won't hydro a tank older than 1991, and that therefore my tanks are useless. Seems odd to me. If a tank can pass hydro why would it otherwise "expire"? Can anyone confirm this?

 

[chrpai]

Your instructor is either ignorant or corrupt. You'll have to decide which.

Read this thread for a list of places to go to for a hydro:

http://www.scubaboard.com/forums/fl...rostatic-re-testers-orlando-do-plus-test.html

 

[rongoodman]

Are they aluminum or steel? Some older aluminum tanks were made of the 6351 alloy which is subject to stress cracking, leading shops to avoid older aluminum tanks entirely. There should be no problem at all with older steel tanks.

 

[chrpai]

1991 isn't the accepted cutoff date for a 6351-T6 alloy tank.

Thanks that could be suspect are:

ll DOT-3AL tanks manufactured under one of the following exemptions or special permits: 6498, 7042, 8107, 8364, 8422
All composite cylinders manufactured under one of the following exemptions: 7235, 8023, 8115
All Walter Kidde DOT-3AL scuba tanks.
All Cliff Impact DOT-3AL scuba tanks made before July 1990.
All Luxfer 80.8 cu. ft. scuba tanks (S80.8) made before May 1987.
All Luxfer 72 and 100 cu. ft. scuba tanks (S72, S100) made before August 1987.
All Luxfer 80 cu. ft. scuba tanks (S80) made before January 1988.
All Luxfer 50 and 92 cu. ft. scuba tanks (S50, S92) made before April 1988.
All Luxfer 30 and 63 cu. ft scuba tanks (S30, S63) made before May 1988.
All Luxfer 40 cu. ft. scuba tanks (S40) made before June 1988.
All other scuba tanks made in the US before February 1990 (except Catalina).
All scuba tanks not made in the US.

 

[Sevenrider860]

I have old tanks that were originally stamped 7/90. My dive instructor told me that in the U.S. they won't hydro a tank older than 1991, and that therefore my tanks are useless. Seems odd to me. If a tank can pass hydro why would it otherwise "expire"? Can anyone confirm this?

Your dive instructor is ignorant of the facts.

 

[chrpai]

Your dive instructor is ignorant of the facts.

Or worse.

 

[Bob DBF]

I have old tanks that were originally stamped 7/90. My dive instructor told me that in the U.S. they won't hydro a tank older than 1991, and that therefore my tanks are useless. Seems odd to me. If a tank can pass hydro why would it otherwise "expire"? Can anyone confirm this?

Find a different shop, you are in FLA. I take my tanks directly to a hydro facility rather than to a dive shop that then takes them to the hydro facility. It's faster and cheaper.

Any shop can refuse to fill any tank, but if there is no good reason for their decision, go somewhere else.

In addition, the 6351 tanks can be used but need a eddy current test in addition to hydro and viz, at that point most shops still won't fill them so I dumped mine due to the hassle.



Bob
-----------------------------
I may be old, but I’m not dead yet.

 

[elmer fudd]

The only tanks that have an expiration date are those made of carbon fiber. They're generally not used by divers however. You would typically see carbon fiber tanks being used by fire fighters, paintballers and airgunners. Their buoyancy characteristics make them unsuited to diving. They have a fixed 15 year lifespan.

 

[ttriton]

I know on or AL tanks for fire department, they now have to ultrasound test them and then hydro test; if they are made before a certain date. I think its before 94. I'd check with a fire service place, that's usually where the dive shops bring them anyway.

 

[abyss_scuba]

Please lets not be so harsh. Remember tank will explode - and they do explode - when they are being filled. You the customer are not standing next to the tank, a shop employee is. They have the right to be as cautious as they want to be for THEIR safety. Up here in NY I know of one shop that also adheres to the 1990 rule. Again that is his choice and since his wife helps out in the shop and his children are always at the shop how do you think he would feel if his family were injured or killed for the price of a tank fill? Shop around but if no one wants to fill the tank then for all intents and purposes it is an expired tank. I love this sport but will not ask anyone to put themselves in harms way, not a student not a shop employee not anyone.