Worthington HP 100s failed first hydro

[halocline]

The "rounding procedure" prepares a hot dipped galvanized cylinder to respond to the actual test. It's not exactly doing it twice but it's a reasonable analogy. Failing to include the rounding step has resulted in unjustified condemnations.

Pete

I know about the rounding procedure as outline in the PST document that's been floating around and is available on the vdh site. This is something different and not manufacturer-driven. Have you ever heard a hydro tester, several of whom have posted on this forum, ever mention anything about doing hydros on all steel tanks twice?

 

[halocline]

OP here--thanks everyone for your responses. Quite an education for me. The situation has not been resolved yet, but here's where we are: the tanks have been condemned, and are still at the testing facility. My LDS, which is not the testing facility, works often with the testers and knows a lot more about it than I do, and is satisfied that the test was done properly. They are currently in discussions with the manufacturer which is reviewing the data and may want to see the tanks. My LDS is advocating on my behalf with the manufacturer and has told me that they will stand behind the tanks no matter what.

I may report that one day in one of the endless threads about buying from your LDS vs. online.

I would not assume that your LDS knows anything of consequence about hydro testing and certainly they cannot assure that the test was done correctly. The dive shops around here use a hydro facility that is horrible. But, if they are in fact standing behind your purchase and will replace the tanks when (oops I mean if) it becomes clear that they were condemned inappropriately, that's excellent customer service.

 

[Leadking]

OP here--thanks everyone for your responses. Quite an education for me. The situation has not been resolved yet, but here's where we are: the tanks have been condemned, and are still at the testing facility. My LDS, which is not the testing facility, works often with the testers and knows a lot more about it than I do, and is satisfied that the test was done properly. They are currently in discussions with the manufacturer which is reviewing the data and may want to see the tanks. My LDS is advocating on my behalf with the manufacturer and has told me that they will stand behind the tanks no matter what.

I may report that one day in one of the endless threads about buying from your LDS vs. online.

I sold thousands of these when I owned Sea Pearls. Hearing of a Worthington scuba cylinder failing a hydro is a first for me. They are a first class, stand-up company. I am sure they are even more interested in this than this group.

 

[Puffer Fish]

I would not assume that your LDS knows anything of consequence about hydro testing and certainly they cannot assure that the test was done correctly. The dive shops around here use a hydro facility that is horrible. But, if they are in fact standing behind your purchase and will replace the tanks when (oops I mean if) it becomes clear that they were condemned inappropriately, that's excellent customer service.

Matt, Perhaps it is just my paranoia creeping in, but I would have expected the tanks to be returned, with a report. And I have seen terrible hydro facilities also, that shops defended because it sold more tanks.

I don't know, but the pat on the head, with a "now don't you worry" comments is not the same as actually doing anything.

Everything may be very fine, but at this point the reason for the failure is not even clear. Nor is anyone replacing the tanks.

 

[rjack321]

Yes and no look at 180.205. If it has been X'ed out and condemned it is over for that tank. But the round out or system check can be performed to 90% of test pressure prior to the retest. There are also provisions for a second retest in case of equipment malfunctions. I'm just saying that on a cylinder that is in for it's first hydro test after manufactur it is odd that it would fail and a person may want to consider a second test at the appropriate increased pressure to verify before stamping out the DOT spec. Not that it is imposible for a "new" tank to fail but unlikely.

True, if they have a system failure or consider the round out a "test" they can retest with the 10% increase in pressure. But presumably they wouldn't go condemning tanks for either known errors on their part or pre-pressurization which is something between recommended and required.

XS Scuba/Sea Pearls has a hydro test procedure in the back of their dealer manual. I have tried to find it online with no luck.
Basically they outline the procedures for hydrostatic testing of their hot dipped galvanized cylinders. The key point is that hot dipped galvanized cylinders MUST go through a system check or "round out" prior to the actual test.
"Follwing this procedure wil ensure accurate results and reduce the unnecessary rejections."
I am thinking that the op's tanks did not go through that procedure and that is the reason his cylinders where condemned.
My suggestion is that if you are going to take your tanks to the hydro test facility yourself ask them if they know about this procedure before leaving them there or the odds are you may pick up condemned tanks.

Close. The prestretch "round-out" is not required for galvanized tanks per se. Its required of exemption series tanks, the 3442psi tanks by PST, Worthington and Faber. And 3500psi tanks from PST.

There are galvanized 3AA tanks by Worthington for instance, 2400+psi which don't need the prestretch. Also 3AA painted "hp" tanks by Faber 3180+psi which don't require this extra step. Its the 5250psi test pressure of the exemption series tanks which require the "round out".

For everyone else watching this thread - ASK the hydro testing facility if they will do the recommended "90% of test pressure round out" Look at their face when they respond, if you detect any BS leave with your tanks intact and find a different hydro shop. If they say "of course these tanks require it" then leave your tanks for testing with confidence.

PS the round out is actually more of a DOT loophole than anything else. Any pressurization of the cylinder <90% of test pressure doesn't count as a hydro. So the manufacturer recommends "prestretching" the exemption tanks to 85-90% of test pressure then conducting the test. It avoids exceeding the allowable 10% test expansion by basically "prestretching" the tank immediately before the actual test.

 

[halocline]

Close. The prestretch "round-out" is not required for galvanized tanks per se. Its required of exemption series tanks, the 3442psi tanks by PST, Worthington and Faber. And 3500psi tanks from PST.

AFAIK the PST recommended round out procedure is not required by anyone; in fact, most hydro testers probably never heard of it. It has nothing to do with DOT regulations, and any DOT tester can ignore it if he wants to. It's just something recommended by one of the manufacturers.

As usual, chaos, paranoia, and hearsay rules in the scuba cylinder world.

 

[rjack321]

AFAIK the PST recommended round out procedure is not required by anyone; in fact, most hydro testers probably never heard of it. It has nothing to do with DOT regulations, and any DOT tester can ignore it if he wants to. It's just something recommended by one of the manufacturers.

As usual, chaos, paranoia, and hearsay rules in the scuba cylinder world.

Its "required" by PST and Worthington to get their exemption cylinders to pass. Hydro testers who do at least a few scuba tanks have typically figured this out by now since PST issued their first "round-out" memo over 20 years ago now (1987-ish). http://www.hydro-test.com/files/PST E9791 Bulletin.pdf

Worthington had to continue the "recommended" practice to get their tanks to reliably pass too. Both exemption cylinders use a lower test pressure (3/2s working) than a 3AA cylinder (5/3rds working) which is also a source of errors, typically not so many since PST and Worthington both stamp "TP 5250" for "test pressure 5250psi" right on the cylinder crowns.

 

[halocline]

Its "required" by PST and Worthington to get their exemption cylinders to pass.

It's only required if the DOT says it is. Anything else is optional. The manufacturer cannot tell the DOT inspectors how to test their tanks, although in a perfect world there would be some cooperation. As far as test pressure goes, if a hydro tester can't figure that one out on special permit tanks, that's pretty bad.

I've heard a hydro tester say that the PST procedure was "cheating" by PST, I've heard one tell me that the DOT requires re-hydro after tumbling, and I've had one stamp the words "no plus" on my LP72s because he did not have the REE number to give them the plus rating.

Like I said, chaos and paranoia.

 

[rjack321]

It's only required if the DOT says it is. Anything else is optional. The manufacturer cannot tell the DOT inspectors how to test their tanks, although in a perfect world there would be some cooperation. As far as test pressure goes, if a hydro tester can't figure that one out on special permit tanks, that's pretty bad.

I've heard a hydro tester say that the PST procedure was "cheating" by PST, I've heard one tell me that the DOT requires re-hydro after tumbling, and I've had one stamp the words "no plus" on my LP72s because he did not have the REE number to give them the plus rating.

Like I said, chaos and paranoia.

No just stupidity. I have quite a few exemption cylinders, PSTs and Worthingtons and I still ask out pre-test round outs every time I bring them in for hydro. DOT may not "require" the round out, but exemption cylinders will rarely pass if the round out is skipped or if a 3AA pressure ratio is used to test them. Yes, some people view the round out as "cheating" the system. Those people are obviously the ones you want to avoid taking cylinders to.

Its going to be tough to get Worthington to replace the OPs tanks if the round out proceedure wasn't done. As far as the manufacturer is concerned its a "required" step to properly hydro test their cylinders.

 

[Akimbo]

I was just looking something up on the XS-Scuba site and noticed this link on Hydro Retest Procedures.

Technical Service Bulletin

Sorry if it was already posted but didn’t find it on a quick scan.