Sherwood Genesis HP120 fails hydro after only 10 years

[drbill]

I took my Sherwood Genesis HP120 in for hydro last month and when I went to pick it up, it had failed hydro. Since the initial test was dated 6-93, it had only been in service 10 years (although it got a lot of use in that period).

I have heard that the Sherwood Genesis HP100's required a special hydro test procedure. Does anyone know if this is true of the HP120's as well? Not ready to shell out $300+ for a new tank if I don't have to.

Thanks.

Dr. Bill

 

[esmiami]

http://www.pstscuba.com/tech.htm

 

[CincyBengalsFan]

drbill once bubbled...
I took my Sherwood Genesis HP120 in for hydro last month and when I went to pick it up, it had failed hydro. Since the initial test was dated 6-93, it had only been in service 10 years (although it got a lot of use in that period).

I have heard that the Sherwood Genesis HP100's required a special hydro test procedure. Does anyone know if this is true of the HP120's as well? Not ready to shell out $300+ for a new tank if I don't have to.

Thanks.

Dr. Bill

Sherwood has never been the manufacturer of tanks. They are probably Asahi's with Sherwood stickers on them.

The companies that have hydro'ed my tanks tell me that you should never use a tank for more than 10 yrs. without question. Even if the passes Hydro 6 times over 30 yrs.

That's ashame about your tank. Did it ever rust up where you could have developed pits?

 

[Waterlover]

CincyBengalsFan once bubbled...


Sherwood has never been the manufacturer of tanks. They are probably Asahi's with Sherwood stickers on them.

The companies that have hydro'ed my tanks tell me that you should never use a tank for more than 10 yrs. without question. Even if the passes Hydro 6 times over 30 yrs.


Dr. Bill,
Check out the link esmiami posted. Your tank was manufactured by PST. They do have a high failure rate if the test is not done correctly. As far as not using tanks more than 10 years old that is pure BS from someone trying to sell more tanks. I have O2 tanks that were made in the 40's that still get regular use. Get it retested if the shop didn't damage the markings when they say it failed. Good Luck

 

[Bob3]

... you should never use a tank for more than 10 yrs.

Got the name of the outfit that told you that?
I'd like to make sure to avoid bandits that try to pile it that high/or deep, as the case may be.
I have a 1955 USD bottle that has always returned to original volume after testing, & I mean 100% original volume. That's better than a lot of brand spanking new bottles.

Maybe they were talking about Alumnibombs.

 

[DA Aquamaster]

I have seen welding tanks as early as 1909 that have lived hard lives and still pass a hydro with flying colors. The thing about not trusritng a tank over 10 years old is pure BS, at least in regard to steel tanks.

Unless your tank has been overfilled extensively or excessively over the last 10 years or has rusted to the point of pitting inside, it should not have a problem passing a properly conducted hydro test.

 

[oxyhacker]

What exactly did tell you they failed it for? The HPs have had a history of rust probs, but if it was anything else, odds are very good you were screwed by a hydro shop that didn't know the proper procedure for the HP tanks. It is very specific.

The bummer is, once a tank has been failed, its failed. According to the DOT regs, God himself cannot recertify it. You can have it rehydroed if you like, as evidence if you were, say, going to sue the first hydro shop, but even if it passed it would still be condemned.

If you want to make a stink, though, print out the PST test procedures and go to the hydro shop and ask to see their log for your tank's hydro. If they tested it at 5900 instead of 5250, or didn't do the pre-test partial pressurization, then they blew it, and owe you a tank.

This should be a warning to anyone with steel tanks - be sure the shop knows what they are doing! With the HPs, since they are so fussy about test procedures, its worth taking a copy of the PST guidelines with you when you take the tank in.

Oh hey, what did you do with the tank? You can always give it to someone who has their own compressor - like me. Seriously, I'm interested.

 

[Compressor]

Oxyhackers point very true.

I also agree. Tanks service life is not limited to 10 years. I have a tank or two close to 40 years old. Also many others over 10 years old.

 

[drbill]

I checked with the test facility. They "rounded out" my tank prior to testing to 4700 psi, then took it to full test psi of 5250.

My other steel tank (HP100) has passed four hydros and is still good (most recent two years ago at the same test facility).

Expansion was 15.8% which seems very high for steel. No indication from the facility of rust or pitting.

I checked with PST since Asahi didn't start making HP tanks for Sherwood until later. They state no manufacturing problems during that era (despite several reported failures of HP100's of that vintage). PST reps stated "The issue that Sherwood had with the product in the early 90's, was with the external paint they asked us to use. It did not adhere very well and had no bearing on hydro-static testing." If so why were tanks failing as reported by others?

This experience with a PST tank does have me questioning the wisdom of buying one of the new E-series or a standard HP made by them (Yes, I know they have a good rep).

Dr. Bill

 

[Bob3]

questioning the wisdom of buying one of the new E-series or a standard HP

I take it you don't have any problems getting a good fill out there then, eh?
I have a set of the little AGA twins, run 4400 psi. I can't recall the last time I was able to get a fill (full) unless I did it myself.