How long does a cylinder last?

[Perplexed]

I've been looking at the various sizes of argon/CO2 cylinders being sold both on and offline, and got to wondering what size would best suit my needs. Is there a rough rule of thumb as to how many cubic feet of shielding gas one might use, say per linear foot of weld? Or is there another way to gauge how big a cylinder would be good? Obviously, the bigger, the less frequently I'd have to fill it - but also, the bigger, the heavier and more bulky it'd get. I plan to mount the cylinder on a cart with my MIG setup, and move it around my shop or down to the garage as needed. So far, I'm considering a 40-cf cylinder for light-to-medium weekend use. Any advice would be appreciated - thanks!

 

[RPW]

IMO it depends on what your welding and the environment you're working in. I get the largest bottles offered by my gas supplier because it's the cheapest per cubic foot of gas to refill.

 

[LD1]

Yep, the larger ones are cheaper per/cu-ft to fill. And at least where I go, the tank lease is the same. Just a flat $90/yr I think. If I empty a bottle before the year is up, only have to pay for contents, which is somewhere around $50 for 320cu-ft of 75%/25% argon/co2.

But to give you a rough Idea, the most common setting on your regulator is about 20 CFH. So a 40cu-ft bottle will only last for 2hrs of weld time.

 

[Perplexed]

Thanks. Is it any cheaper if you own a cylinder, and just take that to swap with a full cylinder or have yours refilled?

When you say "the larger cylinders," which sizes typically would those be? 80 cf or more?

Two hours of use... hm, actually that's still a fair bit for light welding. I wonder if I spent more than a total of 15 or 20 minutes of actual welding with flux core to fabricate my metal-working table. For small projects, a 40-cf cylinder ought to last a fair while, right?

Also, what's the shelf life of an argon/CO2 mix in a typical cylinder in a shop? I realize ambient temperature, as well as the condition of the valve, will play a part in that determination, but can the mix ever go bad over, say, a year or more?

 

[LD1]

It is more money upfront if you buy a cylinder, but you dont have to worry about a lease payment every year.


BUT...and this is different depending on your welding supplier and location, but if you OWN a tank, most places dont refill your tank. They still exchange them. BUT if you happen to not need your tank filled, and the certification expires on the tank, it is YOUR dime that has to get it re-certified. With leasing, you dont have to worry about any of that.

And unless you really dont weld much at all, 2 hours of weld time goes by pretty quickly. I personally wouldnt opt for anything less than an 80cu-ft tank.

And from there, I think they go up to 125, then 240, and then 320. I THINK.

They use the same size tanks for oxygen, but different CU-FT's because they are pressurized a little differently.

 

[jake98]

The guy at Airgas told me they have cylinders that are almost 100 years old.

 

[crazyal]

Thanks. Is it any cheaper if you own a cylinder, and just take that to swap with a full cylinder or have yours refilled?

When you say "the larger cylinders," which sizes typically would those be? 80 cf or more?

Two hours of use... hm, actually that's still a fair bit for light welding. I wonder if I spent more than a total of 15 or 20 minutes of actual welding with flux core to fabricate my metal-working table. For small projects, a 40-cf cylinder ought to last a fair while, right?

Also, what's the shelf life of an argon/CO2 mix in a typical cylinder in a shop? I realize ambient temperature, as well as the condition of the valve, will play a part in that determination, but can the mix ever go bad over, say, a year or more?

I had to call around some but one of the local supply shop sells 80 cf size bottles. Since that was the larges size I could buy and get filled around here that's what I did. It'll last years if I don't use the welder. I favor buying over renting for limited use, why pay $90 a year if you are not using it. Also if you buy a tank from your local dealer it's most likely used and they will just swap it out with another used tank and refill it later. That means they will take care of the hydro testing.

 

[BXpanded]

The welding supply houses here sell tanks up to 160 or 175 cf depending on the shop. There is no "Shelf life" on the gas. The larger tanks are far more economical long term than the smaller. Especially, if you consider the gasoline you have to use to get that little tank filled in the middle of a project. You can lease larger tanks but portability gets to be a problem. They're flat HEAVY! The big ones are really most practical if you have a pickup and delivery service.

 

[5030]

They aren't tanks. They are bottles and last forever or as long as they pass the 10 year hydro test.

Finally, I prefer and do own all my bottles and I have them filled. The have my company name on them and they aren't beat up.

No lease payment...

No ugly beat up bottles.....

 

[BXpanded]

They aren't tanks. They are bottles

Actually, the OP was correct.:thumbsup: They technically aren't tanks or bottles. They're cylinders, if anyone really cares. My guess is that most of the people that have commented on this thread were aware of the correct term.