Tank Question..

[Superlyte27]

Just read the stampings on the neck of the tank. If it says "2400" then they are the "LP 104's", and they will be tested at 5/3. If the tanks say "3442", then they are the new E-8's. However, I think PST was still calling those tanks LP 104's in 2001.

LOL, i know the difference between HP and LP tanks. I was getting clarification on that question of "was any LP tanks affected".

[Sludge]

LOL, i know the difference between HP and LP tanks.

But many divers don't know the difference between E-Series and HP. And KarsticGator never mentioned anything about HP.

[EEL]

LOL, i know the difference between HP and LP tanks. I was getting clarification on that question of "was any LP tanks affected".

I had a several old 72s (2250PSI) that were condemned because the hydro facility did not perform the pre-strech/round out procedure as required by PST. This is very much an issue with low pressure steels too. Make sure the facility where you get your tanks hydroed is familiar with the pressed steel protocol listed above.
I will also highly recommend Advanced Hydrotest. Dave really knows his stuff, and will treat your tanks like they were his own.....

Dive Safe,

Mark

[KarsticGator]

LOL, i know the difference between HP and LP tanks. I was getting clarification on that question of "was any LP tanks affected".

I wasn't being condescending, I was trying to answer you question. Ill rephrase... the hydro testing for the older PST tanks (the ones stamped 2400) are NOT effected. You only need to be concerned about the new PST tanks (stamped 3442).

And they can call them E-8 130's, but they are always PST LP 104's to me.

[JS1scuba]

Joel, I just had two X7-100s fail on their first hydro with initial test dates of August 2005 and September 2005. I am not aware of them ever being overfilled - at least more than the usual 200 psi over until they cool - even in North FL. They have also not seen a great number of cycles as they have not been my go to tanks. Worthington has a procedure that is essentially identical the PST procedure but it only indireclty references the need to re-zero the burette, thus my concern is that both tanks failed due to a failure to properly perform the round out proceduce prior to the test.

My understanding of the need for this procedure with heat treated special permit tanks is that they are no longer perfectly round in cross section following the heat treatment process. Consequently when brought up to pressure, the tank does round out and increases its internal volume - but is not doing so do to excessive permanent expansion. That expansion due to normal rounding of the tank, if not properly zeroed out is what causes tanks to 'fail' a hydro test if the round out process is not properly done.

I have not gotten the test report back from the shop yet but when I get it, what do you recommend?

Worthington cylinders have had inconsistent manufacturing of the scuba series since they got into it. I've seen 1st hydro failures on them. Divers need to appreciate that a cylinder of any type is NOT GUARANTEED to pass a hydro test. That's precisely why a test is done every 5 years. Hydrotest facilities are very careful with what they do. They understand how to test cylinders. Either the cylinder passes or it does not. I know that part sucks but its how it is.

My recommendation is that the cylinder be taken out of service if it failed a hydro test. If you want to make issue of it then contact the manufacturer. Send them the cylinders and have them inspect the cylinder. They can internally run another hydro test and while they cannot put that cylinder back into service it may be something that will help them with future cylinders.

It's not what you want to hear but the bottom line is this. When a cylinder fails hydro test it's done.

Cheers
JDS

[BobK]

This makes sense to me. I would hope they have not destroyed your tanks before you can get a second test done, assuming they did not use the process where the zero was set at 85-90% of WP.

Once they fail, they can't be passed. Unfortunate, but these tanks are done.

Joel beat me to it...

[JS1scuba]

I don't have any firsthand knowledge of a single hydro failure of a 2400 PST cylinder, even ones that have been pumped to 3600 for 35 years. But I know some people whose logic says, "If we can take 2400 tanks to 3600, let's take 3442 tanks to 4400." I believe this is overfilling them, and when you test them at 5200psi some are going to fail.

Around 2004 when PST and Faber went to making 3442 psi exempt series cylinders they both went out and made an 80 cuft cylinder rated at 2640 psi to compete with the aluminum 80. This was a thin wall cylinder that was light and had all the similarities to an alum tank but not the weight or size. It fell under the E series exemption getting a 3/halfs hydro as well ........ the manufacturer made it really clear that this cylinder should not be overfilled. We had some of them. When you filled them they would get very hot very fast, they would float when empty. BUT they were inexpensive as an aluminum cylinder.

I think a few hundred were made by Faber and not much more by PST. I have not seen them in years. I think I still have one or two on my rental rack.

Cheers
JDS

[DA Aquamaster]

Divers need to appreciate that a cylinder of any type is NOT GUARANTEED to pass a hydro test. That's precisely why a test is done every 5 years.

That's something nice to say but it is oddly not how steel tanks are sold - pick pretty much any website, sales brochure etc. Now, it may be true the tank is not guarenteed to pass, but the expectation is certainly created. Certainly, no one told me to expect to throw them away after 5 years when I bought them.

But if it is indeed true that XS and Worthington are ok with properly used tanks failing at 5 years, and that neither Worthington nor XS scuba will stand behind their product, then it is equally true that I am not likely to ever buy another 3442 psi tank again, and assuming I can find anything else, I am not inclined to buy any tank from XS Scuba or Worthington.

The other factor here is that over 25 years of diving, I have owned well over 30 tanks many of them for several hydro test cycles and the only tanks I have ever had fail have been these two XS Scuba/Worthington X7-100s. Makes me wonder how the other two X7-100s I own will fare when they come due for hydro.

[den]

I have 4 120lp org hydro date of 1995 and last hydro of 2010. The tanks are 3aa alloy steel.
The pressure has been as high as 3200 psi. On a few fills. If they fail next year i will be upset, but
when i started scuba diving the cost was just part of scuba diving. If they fail next year i will
let you guys know if they fail /pass.

[Sludge]

Makes me wonder how the other two X7-100s I own will fare when they come due for hydro.

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