PST LP 95 Failed first hydro-Rare?

[aquaoren]

The Faber US LP tanks and EU HP tanks are different tanks, period. Different metal, different weights, different volumes.

With European HP, do you mean 200 or 300 BAR?

 

[jonnythan]

I mean that the tanks people point to to say "this is the same as the US tank, and over there they let you fill it to xxx psi!" are actually *not* identical to the US tanks.

 

[DepthCharge]

HI Guys, My 5 year old PST LP 95 just failed it's first hydro at my LDS. It wasn't from rust, they said it failed to return to specs after testing. The shop said the tank had probably been over-pressurized. I bought this tank from a guy on Ebay in the Fla Keys a little over a year ago (I notice he is still selling used PSTs). I never over-pressured it and I usually stored it with about several hundred pounds in it.
My question, with all the threads on how people are regularly are over-filling these tanks, are there other tanks like mine that are failing there first hydro?

I routinely filled my PST 95's to 3500-4000psi when I was diving OC. They passed with a + rating X 2. I myself wouldn't use a LDS to hydro tanks. Take them to a gas supplier. They'll do it for about 1/2 the price....and have interest in selling you new tanks:54:

 

[Hoosier]

I feel good!!

p.s. I am lot Leaking

Oops! It was my mistake.... Leadking, not Leaking!!!!

 

[roakey]

All PST hot dipped galvanized SCUBA cylinders must be hydro tested following a strict, special protocol specified in PST’s D100 bulletin. Not following the protocol can result in false failures, which sounds like what happened in this case. One of the hazards of eBay is that you did not get the original PST documentation that ships with every cylinder. Since the hydro facility was not made aware of the contents of the D100 bulletin before the test, unfortunately you have no recourse at this point. Not following the instructions spelled out in D100 invalidates the cylinder’s warranty*.

Here’s the current D100 bulletin:

http://www.underctek.com/open/boards/bulletinD100.pdf

Here’s a scanned in 1997 version of the same bulletin I received when I got my PST 104s:

http://www.underctek.com/open/boards/bulletinD100.jpg

Note the requirement that before the actual test, the cylinder must be pressurized to 85% to 90% of test pressure (interesting, the 1997 bulleting says 80% - 90%), the pressure must be released, the burette zeroed and then the actual test may take place.

Hope this helps next time.

Roak

*Not that the warranty is good anymore if in fact PST is out of business, but hopefully this will keep your existing PST cylinders from being failed by the hydro facility...

 

[drbill]

My first PST HP120 failed its second hydro and badly. It did not return to spec either. I never used it on boat dives and never overfilled it, however one of the LDS'es here may have hot filled it frequently. I have a second PST HP120 that passed hydro last year... bought it used from my dive buddy/instructor Karen. Don't fill it at the that LDS.

 

[wreckchick]

I dare say that any given steel tank has a very strong likelihood of failure if the 90% test run isn't done. Yes, overfilling and hot-filling can stress the tanks, but not following test protocol will fail them far more often than a 10 year old tank that was occasionally hot filled to rated pressure.

R

 

[pescador775]

Hot filling, humbug. If presented a choice of filling a tank at 150F or -10F I would take the "hot fill" every time. Cold steel is not nearly as stretchy as warm steel. IMO, failures of PST tanks are most likely due to quality control problems at PST or their suppliers, or due to neglect or indifference by the hydro tester.

 

[drbill]

My PST HP120 failed on its second hydro- same reason. Even a local fill station manager suggested it was due to their hot fills.

 

[captain]

I dare say that any given steel tank has a very strong likelihood of failure if the 90% test run isn't done. Yes, overfilling and hot-filling can stress the tanks, but not following test protocol will fail them far more often than a 10 year old tank that was occasionally hot filled to rated pressure.

R

Anyone bringing in a hot dipped galvanized steel tank for hydro should also bring a copy of the test procedure and be absolutely sure the tester will follow it.