Aluminum tanks

[DA Aquamaster]

Hey Mr. Know it all - it was indeed a fatality, and while I was over-exaggerating saying the fill op was cut in half, she was indeed killed, and several others severely injured. Here is the thread on it: http://www.scubaboard.com/forums/accidents-incidents/65766-accident-cave-excursions.html

Now I could care less if you fill one, but I certainly wouldn't, nor would I ask one of my fill operators to do it.

I remember this thread and this accident very well. It was a little more than 3 years ago, not 8 years ago and we are talking about different accidents.

I hate to burst your bubble but the accident you are referring to was caused by filling and more importantly by dropping a possibly improperly cleaned O2 cylinder that was, ironically enough, made from 6061-T6 aluminum alloy.

From the thread you cited:

"Luxfer just updated their news release. The major point seems to be that the tank is a 6061 alloy. Luxfer news link


August 23, 2004 — Investigators continue to believe that the July 27, 2004 incident in Luraville, Florida was caused when an operator was about to fill oxygen into a scuba cylinder that was not designed for oxygen use and, most probably the valve and/or cylinder had not been purged of all organic matter. Ignition from the fall caused the organic matter in the cylinder to burn, which caused the resulting fire and explosion.

Investigators have determined that the cylinder was made of aluminum alloy 6061. Investigators have ruled out the cylinder as a cause of the explosion."

For two very obvious reasons, sustained load cracks were not even on the radar screen for this accident other than as rampant and incorrect speculation before the facts were even determinined.

I'd suggest next time to quote a previous thread or purport to have an informed opinon that you actually read the entire thread and maybe even do some independent research to ensure you are in fact informed.

It's the repetition of incorrect information by well meaning but less than rigorous with the facts people like yourself that continue to propogate urban legends like the "6351-T6 tanks are dangerous" myth.

Your statement that you would not require your fill staff to fill 6351-T6 tanks suggests you have fill staff and adds support to the argument that many dive shop employees, fill station managers, dive shop owners, etc, are badly misinformed about the abscence of risk associated with 6351 tanks properly inspected under current safety inspection protocols and the realities of 6351-T6 tank safety since those protocols were adopted.

 

[DA Aquamaster]

Ummmmmm..... reconsider the profit margin for a LDS on 2 hydros over 5 years vs. the sale of a new tank. The profit margin is far greater on the hydros than the sale. Did someone say "flawed thinking?" Perhaps just maybe the LDS IS thinking safety first to take a lower margin of profit?



Did someone say earlier that "Implying [] is irresponsible and prefers profit over safety is slanderous"? Ummmmmm....

I'm sorry, but neither one of your arguments makes any sense. They either take my comments out of context or have serious logical flaws in how the rebuttle is constructed. It makes it appear to be more of an attack on credibility than a solid logical argument.

 

[magicwanz]

I'm sorry, but neither one of your arguments makes any sense. They either take my comments out of context or have serious logical flaws in how the rebuttle is constructed. It makes it appear to be more of an attack on credibility than a solid logical argument.

What's so hard to understand about a business (in this case a LDS) choosing not to maximize a profit margin??? In other words, there is another agenda called safety. Sorry but it just doesn't get more logical than that.

 

[DA Aquamaster]

My statement was in reference to Luxfer and and nothing to do with the LDS perspective of the profits of selling new tanks versus hydro tests, etc.

But you do bring up a good question, why would a Local Dive Shop pass on the extra profit of hydro test, VIP and fill on an old tank and in the process annoy a customer by forcing them to bear the additional expense of buying a new tank all over a safety issue that does not in fact exist? Maybe many shops just are not aware of the facts surrounding 6351-T6 tanks and the effectiveness of the current test protocols.

Your suggestion of a safety agenda also brings up the possibility of a double standard with regard to safety agendas. You would want to ask yourself if a given shop that refuses to fill 6351-T6 tanks due to safety concerns also fills AL 80's to 4000 psi and/or fills low pressure steel tanks to 3550-3900 psi? If so, I suspect some other motivation than an overriding concern for safety is at work and that the shop's arguments about the safety of 6351-T6 tanks, or at least the logic underlying their safety concerns may be flawed. After all, filling a 6351-T6 tank is not illegal and does not violate any industry standard, while overfilling either an AL or steel tank clearly violates both and would leave the shop at risk of not being covered by their insurance carrier in the event of an accident.

It would be a question that would have to be asked on a case by case basis.

 

[magicwanz]

My statement was in reference to Luxfer and and nothing to do with the LDS perspective of the profits of selling new tanks versus hydro tests, etc.

Your suggestion of a safety agenda also brings up the possibility of a double standard with regard to safety agendas. You would want to ask yourself if a given shop that refuses to fill 6351-T6 tanks due to safety concerns also fills AL 80's to 4000 psi and/or fills low pressure steel tanks to 3550-3900 psi? If so, I suspect some other motivation than an overriding concern for safety is at work and that the shop's arguments about the safety of 6351-T6 tanks, or at least the logic underlying their safety concerns may be flawed.

It would be a question that would have to be asked on a case by case basis.

Yea I agree, thats a good point. The LDS where my loyalties are certainly would never fill an AL cylinder (rated to 3000) to 4000, highest pressure I've ever seen coming from the same was about 3200.
However if "given shop that refuses to fill 6351-T6 tanks due to safety concerns also fills AL 80's to 4000 psi and/or fills low pressure steel tanks to 3550-3900 psi" I would also wonder where the logic is. Point well taken DA.

 

[WD8CDH]

Hi DA Aquamaster,

The reason that I am asking is I have a set of triple tanks (UDS-1 System) that now require the eddy current testing. Unfortunatly, they do not have the normal SCUBA thread and I have yet to find a shop that has the proper 1.250-12-UNF-2B neck thread probe. If I end up having to ship them somewhere for eddy current testing, I would prefer to only ship them once every five years and do the DOT required annual Visual only locally in between the 5 year eddy current tests and hydros.

Ron

As far as I know the every year eddy current inspection will remain a scuba industry standard just like the VIP.

The annual VIP for scuba tanks is also just a scuba industry standard - a visual inspection is only required by law when the cylinder is requalified (hydro test and visual inspection) every 5 years.

 

[Scared Silly]

DOT required annual Visual only locally in between the 5 year eddy current tests and hydros.

The annual visual is a scuba industry standard. DOT requires a hydrostatic test every five years as part of this test a visual inspection takes place (and for 6351 cylinders the eddy current test).

As for finding the fitting need for your cylinders if your local shops do not have the fitting needed and do not want to spend the $300 for it I would call the mfg (Visual Eddy and Visual Plus) to see who has bought one in your greater area.

 

[WD8CDH]

I don't mind an annual visual, I just don't want to have to send away for a visual PLUS every year.