Tank buoyancy numbers

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They both passed the hydro in 2010 and I've only filled them a little over so they would be at about 2475 when cooled. According to the guy I picked them up from the hydro tester expected both tanks to fail, based upon his previous experiences. These two tanks are essentially the same as a steel 72, only shorter. I have a '62 Sportsways steel 72 with a 1/2" valve that initially failed the hydro test (same tester) but after he bled the system it passed. I'm beginning to wonder if I should get a new hydro tester.

You should definitely use a new hydro tester. The statement that he expected them to fail due to his experience points towards an incompetent technician.

BTW, you are legally entitled to get copies of the hydro records (they are basically public property per DOT). I did it once because a hydro facility failed all three galvanized cylinders I took for testing. To make a long story short, he bought me three replacement steel 72. He had to contact a couple of dive shops to find steel 72. I insisted I did not want new steel tanks, I wanted direct replacements.

A few years later I still reported him to the regional DOT inspector. My report turn out wasn't the only one. He still ha sa license, but he has been warned.

Galvanized cylinders need to go through the proper pre-test procedure. If the hydro facility does not agree to the proper procedure, take your cylinder and money to someone else.
 
You should definitely use a new hydro tester. The statement that he expected them to fail due to his experience points towards an incompetent technician.

BTW, you are legally entitled to get copies of the hydro records (they are basically public property per DOT). I did it once because a hydro facility failed all three galvanized cylinders I took for testing. To make a long story short, he bought me three replacement steel 72. He had to contact a couple of dive shops to find steel 72. I insisted I did not want new steel tanks, I wanted direct replacements.

A few years later I still reported him to the regional DOT inspector. My report turn out wasn't the only one. He still ha sa license, but he has been warned.

Galvanized cylinders need to go through the proper pre-test procedure. If the hydro facility does not agree to the proper procedure, take your cylinder and money to someone else.

What, exactly, is the pre-test procedure? guruboy also mentioned it. Am I the only one who doesn't know about it?

I have a copy of the paper that says the tank was condemned but there isn't much information on it besides the serial number of the tank. It says it failed due to "Excessive permanent expansion." Was I supposed to get a detailed report? This is my first failed hydro test.
 

That's great info! Now I need to determine if the tanks were pre-tested. And, if not, my perfectly good galvanized tank may have been condemned. Has anyone ran into the argument that a particular tank was not manufactured by PST? It appears that it shouldn't make any difference who made the tank, but I just want to be prepared. My tanks have "VOIT" stamped on them so I don't know who actually made them. Is that info on the tank somewhere, along with the serial number perhaps? My Sportsways tank has a "VH" stamped on it and the brother of the one that failed has "HM 14495" as the serial number. Several spaces past the ICC number is the letter "A." A few more spaces and it is stamped "VOIT."

Is there any chance that DOT will investigate to see if it was pre-tested? They wanted to keep the tank saying that the DOT requires either the condemned tank or a copy of a report. Since the tanks was stamped "CONDEMNED" I didn't see any point in keeping it. Now I'm thinking I should have it re-tested by another facility that knows to do the pre-test.
 
Just so you know, they are NOT required to perform the pre-test procedure. It was recommended by PST for their galvanized tanks to prevent false positive failures.

However, it is not a required procedure. So even if they didn't perform it, they did nothing wrong.

Did they stamped CONDEMNED over the DOT specification stamps? If so, there is no way for you to keep using that tank.
 
Just so you know, they are NOT required to perform the pre-test procedure. It was recommended by PST for their galvanized tanks to prevent false positive failures.

However, it is not a required procedure. So even if they didn't perform it, they did nothing wrong.

Did they stamped CONDEMNED over the DOT specification stamps? If so, there is no way for you to keep using that tank.

Thanks for clarifying about the pre-test NOT being required.

I did not want the tank back in order to use it, only for the possibility of having it re-tested with the pre-test to find out if it was a case of a false positive.
 
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Thanks for clarifying about the pre-test NOT being required.

I did not want the tank back in order to use it, only for the possibility of having it re-tested with the pre-test to find out if it was a case of a false positive.

I have been putting off replying to this until I talked to someone that actually known’s something about contract laws and regulations. After talking to our legal counsel at work I wrote the following email to a friend:


"All galvanized cylinders should go through the pretest expansion procedure. This applies to all hot dipped galvanized cylinders (special permits and 3AA codes). Many call the pre-test procedure, the "round-out" procedure, but it turns out that that is not accurate.

The galvanizing coating is a bonded zinc layer. The zinc layer is very thin. It is so thin that it is not a structural component, but it still behaves as a by-metallic composite structure. The zinc layer is very thin, but it still affects the rate of elastic expansion return of the overall composite structure.

The pre-test requirements just involve pre-stretching the cylinder by pumping it to 90% of the test pressure. Holding it for about a minute and then releasing the pressure. Then performing the hydro test.

This requirement is not from the DOT. It is from the manufacturer and it doesn't conflict with any DOT regulation or code (this is very important).

Some have argued (in ScubaBoard) that because it is not a DOT requirement the facility is not required to perform it. Well that is not exactly accurate either. The DOT may not enforce it, but you can still take it to a small claims court for violating a manufacturers requirement and ruining your personal property.

I asked this to our legal counsel (at work) and she agreed that the manufacturers requirement is still holds if a shop agrees to perform a service on that equipment. I am not a lawyer (I am engineer), but my argument to her was that if I take my car to a certified auto-mechanic to perform a required service. The manufacturer of my car very specifically provides a required procedure on how to perform that service. The mechanic decides to do it his own way for whatever reason and he ruins my car. He is liable for the damage he caused by not following the manufacturers required procedure.

That should be the end of the story, but as always, very few things are that easy. According to our legal counsel (again I am not a lawyer) the judge in a small claims court may have a lot of latitude to decide. She agreed that I have a strong case, but normally nothing is that simple... "



I have personally have had tree cylinders replaced by a hydro tester that erroneously condemned them. It never went as far as even needing to threaten with small claims court or even reporting to DOT. I just politely requested the test data and when I saw it I notice several discrepancies… It didn’t take much before he realized that he screwed up.



If anyone else has actual relevant legal knowledge please share with us.
 
Depending on your venue, lesser judges (who are not required to be lawyers, and are not technically even full judges) are usually elected in small towns or appointed, a popularity contest and nothing more. They are also in many areas known to be "proconsumer" and will rule against the big guy simply to stay popular. So, small claims courts in the US are not quite a stellar example. In fact in the US, the American Bar Association came out with a stunning condemnation of the NY state traffic courts, which are similarly staffed all over NY. And very often found to be corrupt or inept--with no one caring to address that issue.

On auto mechanics? Uh, yes, but no. In fact the state courts and federal ones have ruled on that long ago. If the manufacturer says "Bubba didn't follow the right procedure, and he made the car run backwards" then the manufacturer actually STILL HAS TO HONOR THE WARRANTY unless they can show express proof that Bubba screwed it up. It isn't enough to say "Bubba might have" or "Bubba must have", they actually must show specifically what Bubba did, and how that was the actual cause of the problem.

And since there are at least two lawyers in every court suit...That means if you ask one lawyer for an opinion, there is a solid 50% chance they are going to be wrong. Right?

And that's ignoring the way that various courts contradict each other, overrule each other...all that fun stuff.

A professional shop "should" follow all applicable procedures, including the manufacturer and the regulator. But AFAIK there's no mandate that they have to follow the manufacturer's policies. That's just good old common sense, and that's something damned hard to find these days.
 
I have been putting off replying to this until I talked to someone that actually known’s something about contract laws and regulations. After talking to our legal counsel at work I wrote the following email to a friend:


"All galvanized cylinders should go through the pretest expansion procedure. This applies to all hot dipped galvanized cylinders (special permits and 3AA codes). Many call the pre-test procedure, the "round-out" procedure, but it turns out that that is not accurate.

The galvanizing coating is a bonded zinc layer. The zinc layer is very thin. It is so thin that it is not a structural component, but it still behaves as a by-metallic composite structure. The zinc layer is very thin, but it still affects the rate of elastic expansion return of the overall composite structure.

The pre-test requirements just involve pre-stretching the cylinder by pumping it to 90% of the test pressure. Holding it for about a minute and then releasing the pressure. Then performing the hydro test.

This requirement is not from the DOT. It is from the manufacturer and it doesn't conflict with any DOT regulation or code (this is very important).

Some have argued (in ScubaBoard) that because it is not a DOT requirement the facility is not required to perform it. Well that is not exactly accurate either. The DOT may not enforce it, but you can still take it to a small claims court for violating a manufacturers requirement and ruining your personal property.

I asked this to our legal counsel (at work) and she agreed that the manufacturers requirement is still holds if a shop agrees to perform a service on that equipment. I am not a lawyer (I am engineer), but my argument to her was that if I take my car to a certified auto-mechanic to perform a required service. The manufacturer of my car very specifically provides a required procedure on how to perform that service. The mechanic decides to do it his own way for whatever reason and he ruins my car. He is liable for the damage he caused by not following the manufacturers required procedure.

That should be the end of the story, but as always, very few things are that easy. According to our legal counsel (again I am not a lawyer) the judge in a small claims court may have a lot of latitude to decide. She agreed that I have a strong case, but normally nothing is that simple... "



I have personally have had tree cylinders replaced by a hydro tester that erroneously condemned them. It never went as far as even needing to threaten with small claims court or even reporting to DOT. I just politely requested the test data and when I saw it I notice several discrepancies… It didn’t take much before he realized that he screwed up.


If anyone else has actual relevant legal knowledge please share with us.

Thanks Luis!

My personal monetary loss is quite small (I think I paid about $8 for the set of twins including the manifold, bands, backpack, etc) it's just that I no longer have a set of twins. I printed out the information that you posted about the need to do the pre-test and will supply future hydro-testers with that information, and hopefully be able to discuss it with them. In this particular case I am at fault, at least somewhat, because I gave the testing facility my incorrect phone number so the tester was unable to contact me with any questions or concerns. I'll be more careful in the future.

Meanwhile, I may call the tester and ask him about this particular tank. The first time I took tanks to him he showed me the testing station and explained everything to me in detail. I have an ol' Sportsways tank with a 1/2" J-valve which he said initially didn't pass but he bled the system, re-checked everything, and it passed. In this case, if he is ignorant about pre-testing galvanized tanks, bleeding the system and re-testing might not have been adequate. This particular tank had enough rust and spotting that someone who wasn't adept at VIPs might have condemned it but he knew what was OK to pass and what was not and recommended having it tumbled. So, aside from possibly not knowing about the pre-test, he seems completely competent.
 

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