Luxfer 14cuft 2015 psi Cylinder - hard to find - new hydro $125 shipped

[-JD-]

We're chasing our tails. I'll contact PCI and ask them to follow up with Luxfer. They have  extensive contacts within the industry. A straightforward question to answer. Do you have s picture of the serial number?

I was typing an info request to Luxfer on their contract form as you posted this ...

Hello,

I have a S14 cylinder (Marked: DOT-3AL2015 KK09007LUXFER10A87)

Can you tell me if this cylinder was made from 6351 or 6061 Alloy?

When did the S14 series cylinders transition to 6061, as I'd like to find a replacement 6061 version to avoid the SLC risk?

The available support documents that I can currently find are mute or non-determinative on the alloy(s) for this series cylinder. Can you provide, or link me to, published documentation on the alloy for the S14 series?

Thank you so much for your assistance!

I'll report back as well if/when I hear something from them.


Update 1: from Luxfer "Thank you for your inquiry on our website. We no longer supply these tanks and sold that sector of the business in the US to Thunderbird. Please contact them in regards to your inquiry". They provided contact info, and I have sent an email to Thunderbird.

Update 2: from Thunderbird "That particular cylinder was not made at this plant in Graham, NC. We have no records on that size cylinder, so I’m not sure when Luxfer had changed the aluminum alloy in that one. Attached is the information that I have on cylinders that were produced by Luxfer in the 80’s when the alloy was changed. I also have information on how to do an Eddy Current check for those older cylinders." They attached a scan of a hardcopy of Dates when Luxfer changed its aluminum alloy from 6351 to 6061 - Luxfer Gas Cylinders and the CFR page.

Commentary: So probably a dead-end on the "general consumer" access to info. Hopefully those with insider access will have better results.

Update 3: Trying again with Luxfer ...

Thank you for the referral to Thunderbird. Alas, they are unable to provide assistance, as they evidently were never provided the appropriate records. [See quoted below].

I am concerned as this is a serious potential safety issue.

Luxfer still publishes the information for most of the cylinder variants:
ex: Sustained-load cracking (SLC) in ruptured scuba cylinder made from 6351 aluminum alloy - Luxfer Gas Cylinders
Dates when Luxfer changed its aluminum alloy from 6351 to 6061 - Luxfer Gas Cylinders

Would you be so kind as to inquire internally and see if Luxfer has the appropriate information? Specific information on the S14 alloy(s)/changeover date would be very helpful!

Thank you for your continued assistance.

Update 4: from Luxfer "I apologize for the misdirection; I thought Thunderbird did have the records. I have copied our Customer Service team who can raise this issue with our quality and get you the answers needed. Customer Service – Can you please help with the below? Thank you!"

Commentary: Amazingly prompt and friendly support on a close to 40 year old product!

 

[Scared Silly]

Been there done that. I have direct contact at luxfer that I am reaching out to.

 

[OMyMyOHellYes]

I wonder if these were ever intended to be purely used as scuba tanks? The 2015 PSI service pressure seems to suggest they may have been intended for something like oxygen use?

I have one of these bottles, made in 1992, but I've never tried to dive it. It is very light and with a larger external dimensional volume closer to an AL19 than an AL13, I would expect it would be positively buoyant at all intended pressures. (I should fill my dunk tank this coming week and just drop it in to verify the degree of positive buoyancy).

I also worry about having it filled at any scuba fill station unless I'm standing right there to make sure it's only filled to 2,000 PSI. I bought it because I thought it kinda cool - and it looks like it just got pulled from the original Luxfer factory box, but I don't know its utility for diving, unless I O2 cleaned it and kept it handy as a DCS first-aid O2 bottle. One of the things I remember picking up on when I acquired it was that they were no longer produced and IIRC were represented as sought after by certain segments, but I've not been able to figure out what the segment or purpose is.

 

[Scared Silly]

I wonder if these were ever intended to be purely used as scuba tanks? The 2015 PSI service pressure seems to suggest they may have been intended for something like oxygen use?

Good question. The later ones are marked S14 which the 'S' is typical for their scuba cylinders. Also they are all painted yellow which again is typical of scuba cylinders.

 

[davehicks]

I wonder if these were ever intended to be purely used as scuba tanks? The 2015 PSI service pressure seems to suggest they may have been intended for something like oxygen use?

I have one of these bottles, made in 1992, but I've never tried to dive it. It is very light and with a larger external dimensional volume closer to an AL19 than an AL13, I would expect it would be positively buoyant at all intended pressures. (I should fill my dunk tank this coming week and just drop it in to verify the degree of positive buoyancy).

I also worry about having it filled at any scuba fill station unless I'm standing right there to make sure it's only filled to 2,000 PSI. I bought it because I thought it kinda cool - and it looks like it just got pulled from the original Luxfer factory box, but I don't know its utility for diving, unless I O2 cleaned it and kept it handy as a DCS first-aid O2 bottle. One of the things I remember picking up on when I acquired it was that they were no longer produced and IIRC were represented as sought after by certain segments, but I've not been able to figure out what the segment or purpose is.

I have Six of these 14cf 2000psi bottles and I use them for 100% O2 on my CCR units. I've been using them for about 10-12 years, adding a more as I could pick them up over time. They are ideal bottles for CCR oxygen use. They are both lightweight and you can get a complete fill at only 2000psi. Most providers won't fill oxygen over 2400, so you avoid that problem. Even better, at a remote location where you are just trans-filling the tanks from a big industrial O2 tank, you can get a complete (or nearly) fill without a booster. With a standard 3000psi 19 or 13, you end up with a very short fill at just 2000-2400 from a transfill.

I put a big label on them near the valve indicating "100% O2 - 2,000psi Max". On dive trips or local shops, I've never had a problem getting them filled correctly, and I always make a point of communicating the 2000psi requirement to the fill operator.

At home I use a booster to fill my O2 bottles from a pair of LP95s I fill with 100%.

 

[Pavao]

, but I don't know its utility for diving,

Very popular as a suit inflation bottle with the WKPP divers.

 

[Zef]

Attached is a report of an analysis/evaluation that the DOT contracted back in 1997 after failure of a Luxfer 3AL2015 cylinder.

The report confirms the speculation, in this discussion thread, that these cylinders were made from 6351 alloy and that the 3AL2015 cylinders were (are), at least sometimes, used with O2.

While the report indicates the failure of this particular cylinder was due to mechanical damage to the side of the cylinder as opposed to an issue in the neck/shoulder of the cylinder where sustained load cracking typicly occurs, my personal opinion is that this should not be construed as indicating that these cylinders are not subject to SLC failure. And the analysis of the neck region of the tank along with the performance of a metallurgical analysis discussing the density distribution of the elements of the alloy indicates that there is indeed concern for SLC type failure of the AL2015 cylinders.


Further, my opinion is that the OP is pressing real hard to convince folks that this cylinder type is not a problem in order to push selling the cylinder. The reality is that even if there was some obscure reference that these cylinders were not subject to SLC, it would be difficult for a buyer to find a shop willing to fill the cylinder given that it is made from 6351 aluminum alloy and the fact that the cylinder is 39 years old. An increasing number of shops seem to be setting the bar for filling aluminum cylinders at around the 20-year mark of the cylinder's life.

For those that might be willing to purchase a 6351 alloy cylinder of this vintage for filling with their personally owned compressor, I would point that the risk is not worth the benefit. A brand new Thunderbird AL-19 cylinder can be purchased for $160US, and a brand new Thunderbird AL-13 cylinder can be purchased for $149US.

Unless there is something magical about a cylinder being 14CUFT, then I think the risk of not being able to have this cylinder commercially filled, and the possibility of a SLC related failure far outweighs any benefit purchasing this cylinder has to offer.

-Z

 

[rjack321]

I wonder if these were ever intended to be purely used as scuba tanks? The 2015 PSI service pressure seems to suggest they may have been intended for something like oxygen use?

I have one of these bottles, made in 1992, but I've never tried to dive it. It is very light and with a larger external dimensional volume closer to an AL19 than an AL13, I would expect it would be positively buoyant at all intended pressures. (I should fill my dunk tank this coming week and just drop it in to verify the degree of positive buoyancy).

I also worry about having it filled at any scuba fill station unless I'm standing right there to make sure it's only filled to 2,000 PSI. I bought it because I thought it kinda cool - and it looks like it just got pulled from the original Luxfer factory box, but I don't know its utility for diving, unless I O2 cleaned it and kept it handy as a DCS first-aid O2 bottle. One of the things I remember picking up on when I acquired it was that they were no longer produced and IIRC were represented as sought after by certain segments, but I've not been able to figure out what the segment or purpose is.

They were intended and used as suit gas bottles back when boosters were rare and folks were transfilling argon for suit gas. They were often painted yellow, black or white, threaded in NPS 3/4" and supplied with scuba valves by scuba distributors.

I've never seen one with an O2 valve in it. Nor painted in any variety of green. Also CGA870 valves are 3/4" UNF which is way smaller than NPS threading.

 

[jborg]

They are both lightweight and you can get a complete fill at only 2000psi. Most providers won't fill oxygen over 2400, so you avoid that problem. Even better, at a remote location where you are just trans-filling the tanks from a big industrial O2 tank, you can get a complete (or nearly) fill without a booster. With a standard 3000psi 19 or 13, you end up with a very short fill at just 2000-2400 from a transfill.

I mean, you can fill any tank to 2000 psi and call it full? That AL19 is essentially an AL14 at 2000 psi, just slightly less positively buoyant?

 

[rjack321]

I mean, you can fill any tank to 2000 psi and call it full? That AL19 is essentially an AL14 at 2000 psi, just slightly less positively buoyant?

Correct, the walls are thicker and hence the al19 a slightly heavier tank but otherwise the specs are so close that standing side by side they are hard to tell apart.