I have inherited a small compressed gas cylinder used for Carbon Dioxide to pressurize a beer-keg in a (defunct) refrigerator. Is it possible (or even LEGAL) to have it refilled with oxygen, for a small brazing-torch application?
Thanks,
Flash
To have it filled with oxygen, you would have to have the valve replaced. And they might not like it anyway because most CO2 cylinders are rated at a lower pressure than oxygen cylinders.
However I have had good luck in trading in or trading up cylinders. That is take it to a welding supply and ask what various sizes of oxygen bottles would cost if you traded in your cylinder. You might ask at several outfits.
Dan
Probably NOT. The CO2 tanks are not designed for the pressures that O2 tanks are.
Jim Chandler
your asking if it can be refilled by someone else? Well theres no reason it cannot be filled with oxygen IF you do not exceed the pressure that cylinder was rated at. Here in the UK all cylinders have
I regularly refill smaller cyls from bigger ones as Ive a need to have some portable gear . I also refill small propane cyls from big ones. you need to have the right connection high pressure hoses to do any of this. Transferring liquid propane under pressure needs some careful planning .
Oxygen has special fittings and sealings. Oxygen is very reactive, CO2 isn't. So it certainly is a stupid idea to fill a CO2 bottle with oxygen at any pressure.
Nick
I agree, its a stupid idea IF you dont know what your doing.
If you do know what your doing and you follow the guidelines in my previous post you should be ok.
But as allways the buck stops with you if it all goes wrong. If yove no one to teach you and youve not done it before, dont do it. Like anything else theres a learnig curve with any technology.
If you dont do your research first your likely to screw up.
Sorry, didn't read in your post about replacing the sealant in the bottle's valve. Or checking wether it is resistant to pure oxygen. Anyhow, a stupid endeavor with a high chance of a *very* steep and short learning curve. :-)
Nick
Depending on your local customs in the gas business, it may be possible to trade it in on another type of cylinder. I traded a small oxygen cylinder in on a larger argon bottle and was given $75 credit toward the new bottle. The gas vendors won't cross fill a bottle, though.
For the sake of brevity.
No!
Get an oxygen bottle.
Different fittings, different requirements for cleanliness. If you can find a company that would fill it, please set a video camera on a tripod up the street, so we can see it on the news. :-)
Use the CO2 bottle for shielding gas for a MIG welder. Works for steel, and is a cheap fill.
Cheers Trevor Jones
Your O2 regulator is expecting a particular type of valve (CGA-540) on its tank... The CO2 tank has a different type of valve (CGA-320)... You could probably replace the valve on the tank or create an adapter to go from the tank's valve to what the O2 regulator is expecting... The CO2 tank has a rated working pressure of 1800 psi... The O2 tanks are rated at 2015 psi usually... You might have difficulty getting a gas supplier to put O2 in the tank even if you change the valve... The most economical method would be for you to buy a large O2 tank and have them refill that and then you transfer that gas yourself to the smaller tank as needed... Some of the online dive shops sell the adapters that you might need for creating this sort of setup...
Hell, if you know what you're doing, you can put O2 in a typical 20# BBQ LPG tank... You have to be a bit more careful on the pressure though... The penalty for not getting it right can be a bit severe... But don't worry, Darwin will be there to protect you...
"Grumman-581" wrote: But don't worry, Darwin will be there to protect you... ^^^^^^^^^^^^^^^ No, Darwin protects your surviors.
CO2 cylinders are in demand because of the paintball craze. Every time I go to my gas supplier he is has a lot of CO2 cylinders coming in and ready to go out.
John
I do a lot of things that some people consider unsafe. But you won't catch me putting pure oxygen in a tank that contained hydrocarbons. I can't think of a way to clean the tank so I would think it was safe.
Dan
Yup, not a safe thing to do at all.
High pressure oxygen and a combustable material will definitely ignite.
John
Thanks for all the helpful info, folks. On the advice provided, I did take it to the local welding suplier, and they took it in an even swap for a same-size O2 tank,. charging me $12.87 for the oxygen.. As the tank I took in was outdated on the test, they did charge me $20 bucks for the retest. Fair, I am sure.
They also waxed me $5.00 for the "haz-mat fee" - which might be for anything: taxes? transportation? Who knows?
Anyway, thanks to all who replied.
Now, how about a small companion acetylene cylinder. I trust that Good Saint Potluck will be with me again as flea-market season picks up speed.
Flash
Sounds like a more than fair deal, compared to the prices I have seen around my neck of the woods.
I see plumbers "B" bottle tanks with an air-acet torch on them, going for a little over $100 on a somewhat regular basis. You'll probably find one cheaper than that, if your luck holds.
Be nice to the welding supplier! It sounds like they are willing to work with you on the oddball stuff coming in, and not rape you on the consumables. Worth supporting!
Cheers Trevor Jones
Sounds fair enough - not sure what they consider HazMat either, since there's no real clean-up needed... Might be a fee they charge the delivery truck customers to pay for the most hazardous activity of their day (to their bottom line) - fueling the company truck. ;-)
Some companies don't want to or don't have an easy way to call it a "fuel surcharge" or the customers have a 'contract price' for the supplies. They can't raise their rates to cover that, so they invent something... You came in Will Call, so no HazMat used in the sale.
Don't make a mismatch - if that O2 cylinder is a 20 Cubic Foot, it won't last much longer than a small "MC" Acetylene. And you can't do much more than decorative welding or silver-brazing, this is the size used in "Porta-Torch" sets that AC Repairmen select for ease in hand carry, hauling up on roofs or in crawl-spaces.
Totally Forget About Cutting with MC/20CF cylinders, even with the smallest tips. Hit the cut valve and the O2 tank is flat in seconds. The smallest practical size cylinders for home shop use that can actually accomplish something is the "B" Acetylene and 50CF O2.
During your flea-market runs accumulate two (or three) sets of bottles so you have full spares on hand, because Murphy's Law says your last cylinder always runs out at noon on Saturday, right after the welding supply closes for a three-day weekend. Oxygen never goes bad, and Acetylene is OK to store for years. (First in, first out.)
If you end up with the small bottles the Welding Supply will trade - I traded two MC's straight across for one B. I probably lost a bit on the deal if it was based on "market prices" but quite all right considering what I paid for them. ;-)
Even with a B/50CF you have to take it easy on cutting and welding tip size selection, you Can Not draw more than 1/7 of the Acetylene cylinder volume per hour or you start drawing out the Acetone carrier, and this is very bad.
If you need to cut or weld big stuff, you need to lease a set of big bottles for the duration of the project. Or you can spend a lot and buy cylinder manifolds to draw from several small cylinders at once. DO NOT try to cobble up a manifold system yourself, there are too many ways for this to go very, fatally wrong - as in "KA-BOOM!!"
-->--
This is an exceedingly bad idea. CO2 cylinders are different from all other cylinders. They are not pressurized anywhere near as high as are normal high pressure cylinders, which contain gases like oxygen, helium, argon or nitrogen to name a few. You will also notice you can't thread your oxygen regulator onto the CO2 cylinder. That's because the cylinder valve port is made to the CGA standard for CO2, which is different than the one for oxygen.
If you swapped valves, then someone filling it might think it were safe to fill it to the normal (~2000 psi) pressure for oxygen, and given that a CO2 cylinder isn't made to hold anything like that kind of pressure, it could fail catastrophically. This is why I think it is a really bad idea.
You should either sell the CO2 cylinder - there is excellent demand for those from home brewers and guys who MIG weld with CO2 - or swap it at your welding supply when you're buying an owner oxygen cylinder.
GWE
My experience has been that a oxygen cly can be converted to CO2, but not the other way around. I was able to trade two small cylinders (argon/co2 and oxygen) straight across for a 130 cu ft argon cylinder. I had to pay for the gas and they didn't pay me for my gas. I was still satisfied. You may be able to trade for what you want.
John
I have one 20# LPG tank that I could probably put O2 in with a bit of a cleanout with Simply Green... It's never held LPG... I only use it as a portable air tank that is filled from an oil-less compressor... Of course, I don't really have a reason to do it... If I want to put O2 in a small tank, I'll grab a spare SCUBA tank like a steel-72...
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.