Overfilling steel tanks

[dvrgaryc]

Okay, I'm not really sure if this is the right place to post this, but I'm hoping to get a straight answer from SOMEONE on this board. I'm getting a little tired of the so-called "experts" that try to tell me it's okay to overpressurize their tanks. Now I know there will be some people out there who say they have been doing this for years and never had a problem, but are THEY the ones standing at the control valves filling the tanks? Let's see if I can remember their logic;
"Steel tanks never blow up, only aluminum tanks do that."
"It's okay to pump up a 2400 psi tank to 3300 psi."
"I've got double burst discs in the valve, crank it up."
And my personal favorite:
"These are the same steel tanks they pump to 5000 psi in Europe." (psst, little hint dudes, this ain't Europe)
What I'm wondering about is just where this paritcular bit of information started. If a tank manufacturer in Europe makes tanks for the European and American market, how come the American tanks get a 2400 psi rating but the European ones get a 5000 psi rating? Or does the same manufacturer make two completely different tanks for two different markets?

 

[MaxBottomtime]

Tanks in the US are regulated by the Dept. of Transportation. They are the same tanks as in Europe. As with most things where the government get involved, they decide what is best for us. BTW, I overfill my steel tanks every time. They are pressure tested to 167% of the rated pressure for the hydro tests. 20% overfills aren't going to harm them.

 

[Curt Bowen]

Okay, I'm not really sure if this is the right place to post this, but I'm hoping to get a straight answer from SOMEONE on this board. I'm getting a little tired of the so-called "experts" that try to tell me it's okay to overpressurize their tanks. Now I know there will be some people out there who say they have been doing this for years and never had a problem, but are THEY the ones standing at the control valves filling the tanks? Let's see if I can remember their logic;
"Steel tanks never blow up, only aluminum tanks do that."
"It's okay to pump up a 2400 psi tank to 3300 psi."
"I've got double burst discs in the valve, crank it up."
And my personal favorite:
"These are the same steel tanks they pump to 5000 psi in Europe." (psst, little hint dudes, this ain't Europe)
What I'm wondering about is just where this paritcular bit of information started. If a tank manufacturer in Europe makes tanks for the European and American market, how come the American tanks get a 2400 psi rating but the European ones get a 5000 psi rating? Or does the same manufacturer make two completely different tanks for two different markets?

Gary

Do not over fill the tanks. If they want to overfill their cylinders they will find another shop that will.

The cylinders are the same, but USA DOT has set a U.S. standard that you as a dive shop should adhear to.

I myself, over fill my steel 121's to 3100-3200, normally because they cool back down to 2700-2800 but I do it myself, with my compressor.

 

[Northeastwrecks]

but are THEY the ones standing at the control valves filling the tanks? Let's see if I can remember their logic

Funny you should ask it that way. In fact, yes, I am the one standing at the control filling the tanks.

If you choose not to overfill, that's your business and I certainly wouldn't say that you are wrong. I wouldn't frequent your shop, and would tell my buddies to stay away, but that's another issue.

As for why the same tanks have different ratings in the US versus Europe, I suppose that could be attributed to incompetant government 'crats who aren't qualified for a job on the night shift at a 7-11 and who would be pushing shopping carts up main street if they weren't given de facto lifetime employment at our expense (and to our great detriment), but that is also another issue.

 

[Kaos]

My LDS has overfilled my 104 and 98 steel LowPres (2400) in the 2800-3000 range for the last 10 years. They have passed two hydros so far, and given me countless hours of extra fun bottom time.

 

[dvrgaryc]

As for why the same tanks have different ratings in the US versus Europe, I suppose that could be attributed to incompetant government 'crats who aren't qualified for a job on the night shift at a 7-11 and who would be pushing shopping carts up main street if they weren't given de facto lifetime employment at our expense (and to our great detriment), but that is also another issue.

Yeah, I kinda figured that

 

[dvrgaryc]

My LDS has overfilled my 104 and 98 stell LowPres (2400) in the 2800-3000 range for the last 10 years. They have passed two hydros so far, and given me countless hours of extra fun bottom time.

I've got no problem with filling a LP steel tank to 2900-3000 psi and letting it cool off, it's the guys that come in and demand their tanks be filled to 3500 psi that I have a problem with.

 

[murphdivers286]

It is your safety. Do nothing to compromise your safety for anyone.

 

[Paul Evans]

For us lucky divers in the UK we get our tanks filled to

232 Bar for............. funnily enough for 232 tanks

300 Bar for............. funnily enough for 300 tanks

and the Al tanks are rated to 232 as well

I think :06: in Europe 200 Bar is normal, In the Maldives recently 230 bar was the order of the day!

So, being a metric type person can anybody explain how much of a difference it makes on your side of the pond......

Why, if they are the same tanks, are yours filled to such low pressure.............Yes I know about the goverment screwing up, Same here on a lot of things, But this seems total Bo@@@k's

There has to be a reason :06:

 

[Northeastwrecks]

I've got no problem with filling a LP steel tank to 2900-3000 psi and letting it cool off, it's the guys that come in and demand their tanks be filled to 3500 psi that I have a problem with.

Sure. What I do with my own tanks is my business. I don't expect other people to do it. Which is why I learned to mix my own gas.