Nitrogen Tank Weight

[John Spiegel]

Hello,
I bought a nitro tank secondhand. I believe it's a 10# nitrogen tank. I weighed it at 15# with regulator. I was wondering what the empty weight of a nitro tank was to calculate how much nitrogen I have left, but couldn't find anything online. Thought I'd ask here.

 

[Whisky River]

There should be a number stamped into the metal near the neck of the tank that lists the weight of the tank empty. This is usually referred to as the Tare Weight and is sometimes written as TW123 or T123, but sometimes it’s just the number.

 

[hotbeer]

Empty weight is going to vary. Try to find the best match to it on the internet and then find what it's dry weight is. Add the weight of your regulator and hose if you are weighing it with those on.

 

[whoaru99]

And, bear in mind nitrogen will be high pressure gas (unlike CO2 that will be some liquid) so there won't be as big difference in weight between empty and full for a cylinder that size.

 

[John Spiegel]

I am

There should be a number stamped into the metal near the neck of the tank that lists the weight of the tank empty. This is usually referred to as the Tare Weight and is sometimes written as TW123 or T123, but sometimes it’s just the number.

aware of tare weight, but wasn't able to decipher which number on the tank was the weight, as the numbers on the side are not what I'm used to with CO2 tanks.

 

[day_trippr]

And, bear in mind nitrogen will be high pressure gas (unlike CO2 that will be some liquid) so there won't be as big difference in weight between empty and full for a cylinder that size.

Dumb statement retracted ("There will still be a 10 pound difference between an "empty" cylinder and a full N2 fill...")
Brain was set to CO2 mode.

I have a "10 pound" steel cylinder for beer gas but it really should be called "40 cubic foot" cylinder as it's always been filled to a specific pressure, not by weight. I've had it forever and if there's a tare stamp it's hidden under the label that cost me a ton of aggravation when I removed it once. Not doing that again...

Cheers!

 

[camonick]

Pictures?

 

[John Spiegel]

Pictures?

 

[camonick]

That appears to be a steel tank last filled with some kind of CO2/N mixture. Those types of gases are typically filled by volume rather than weight. Most of those stamps are hydro test dates, which are expired by quite a few years. What does the regulator say? That’s the best way to determine the amount of remaining gas in a cylinder like that. The pressure steadily decreases as you use up the gas unlike liquid CO2 which maintains a constant pressure until the liquid has all boiled up and only gas remains.

 

[whoaru99]

There will still be a 10 pound difference between an "empty" cylinder and a full N2 fill...

Cheers!

Maybe, if it's a big enough cylinder but the OP said it weighs 15lb with regulator.

So, subtract some weight for the regulator and it doesn't seem to be a very large cylinder.

 

[whoaru99]

@John Spiegel

What is the physical size of the cylinder, diameter and height?

 

[John Spiegel]

@John Spiegel

What is the physical size of the cylinder, diameter and height?

4 in. Diameter x 24 in height.

That appears to be a steel tank last filled with some kind of CO2/N mixture. Those types of gases are typically filled by volume rather than weight. Most of those stamps are hydro test dates, which are expired by quite a few years. What does the regulator say? That’s the best way to determine the amount of remaining gas in a cylinder like that. The pressure steadily decreases as you use up the gas unlike liquid CO2 which maintains a constant pressure until the liquid has all boiled up and only gas remains.

That's good to know. The regulator said it was running low, but I didn't realize there was a difference between the way CO2 and beer gas regulators measured pressure. I also don't super trust the regulator. I've had to replace a part on it already, which is why I was hoping to verify by weight. Might just be worth refilling if it's anywhere near accurate.

 

[whoaru99]

Those dimensions align with being ~20cu ft cylinder. The difference between empty and full weight would be roughly 1.5 pounds (re. Nitrogen).

 

[beren]

With CO2 you can tell how much you have based on weight. The pressure is useless because most of its liquid. With nitrogen and beer gas there’s no liquid so the pressure actually tells you how much is less and the weight is useless.

 

[Bobby_M]

I'm going from memory here but I believe my 19cuft tanks of 75/25 mix are 1.75 pounds heavier when full than empty.

 

[odie]

that's not gonna last very long

 

[day_trippr]

Actually, my 40cf beer gas cylinder will go for a couple of years before needing a fill.
All it does it push my chocolate stout year 'round, I don't use it for conditioning nor transfers...

Cheers!

 

[beren]

Yeah, use pure co2 to get your beer to the desired carb level then hook to beer gas.

 

[John Spiegel]

Yeah, use pure co2 to get your beer to the desired carb level then hook to beer gas.

I thought the purpose of the gas was to infuse the beer with the nitrogen. Nitrogen and CO2 have impart different mouthfeels on the beer. If you carbonate then push with beer gas, you're not actually infusing the nitrogen.

 

[day_trippr]

There is no "infusion" with N2 as it does not readily dissolve in beer. It's strictly used as a propellant in our application. In other related applications, pubs/bars with long-line dispensing systems use tuned N2/CO2 mixes to propel the beer through crazy long beer lines without adding to the carbonation level...

Cheers!