Help understanding welding tank markings

[sns1938]

I impulse purchased this from a garage sale of sorts. I have a Lincoln WeldPak 100HD (which I was given and need to get running, as it needs a new hose liner for $9 to get running) with gas attachments. The regulator fits this bottle etc.

My questions are:

1) Is this a ''real'' welding bottle or a diving tank which someone set up for welding?
2) What year was it made?
3) Is it in date? When does it need retesting?
4) Did I buy junk?
5) If it is within date, what is the best strategy for filling? Do local welding supply shops vary in price a lot? Do some swap the cylinders and some fill them?

Apologies for no photo of the whole tank, I forgot. It feels alloy and not steel. I believe some of the markings confirm the material and max pressure?

I know it would be too simple, but it does say ''2015'' on it and has a star, but I cannot believe it is only 2 years old and is good for another 10 years. It looks too abused.

Thank you,

 

[Rogue1987]

Are there any more stampings on the tank? I dont believe the 2015 is a hydrotest date, I thought that's a pressure rating. The 03A01+star is your most recent hydrotest. The tank will need to be hydrotested (which shouldn't be prohibitively expensive).

Looks like a normal high pressure cylinder to me. No neck ring saying it was owned by the gas company so it should be a customer owned cylinder.

Gas suppliers can charging hugely diffrent prices for gas, call around for sure. Some places will send your tank to be filled, others will swap it for another tank (be sure to get one without neckband that says it's owned by the gas Co, my praxair ***** about that).

Can't say if ya made a good buy without a price.

Sent from my XT1585 using Tapatalk

 

[crane operator]

Stargold is the praxair name for their shielding gas typically used with a mig welder. I think new tanks run about $200 (depending on size). To fill it will run you around $60-$70, they usually just exchange tanks with you. I exchange at my local oriellys auto parts.
I can't see in your pictures how large your tank is, the size determines the cost new, and the price to exchange/ fill. Prices are for the 4-5' tall tanks (I use that size with my 250amp mig).

 

[Cope]

Prices and practices on tanks vary widely by locale. You have a nice bottle that needs retesting, but my local Praxair doesn't look at them closely, especially if they're clean. I've never had to pay for a retest, and often the bottle they give you is close to needed a test.

 

[sns1938]

Thank you all. That's great info.

I paid $60, and will call around a few welding shops/oriellys to price up hydro test + fill vs exchange. Right now, I'm probably most keen for a test+fill so that I don't get a swap-a-bottle that is going to expire in a couple of years again. If it's getting up too much, then I'll just sell on craigslist and wait for an in-date bottle with some gas in it.

The bottle is only about 2' tall, it's very similar in size to an alloy dive tank.

Thanks all,

 

[Thumper68]

Thank you all. That's great info.

I paid $60, and will call around a few welding shops/oriellys to price up hydro test + fill vs exchange. Right now, I'm probably most keen for a test+fill so that I don't get a swap-a-bottle that is going to expire in a couple of years again. If it's getting up too much, then I'll just sell on craigslist and wait for an in-date bottle with some gas in it.

The bottle is only about 2' tall, it's very similar in size to an alloy dive tank.

Thanks all,

You are better off finding a shop that does exchanges, that size bottle should be a 20 so no more than an hour or so of weld time.

The good part about doing an exchange rather than getting your bottle refilled is that you are in and out in under 10 minutes and back to your project, most shops do not fill on site and even if they did your bottle would just be placed in the que and you would have to wait days to get it back.

I have 1 bottle that size, it is my 2nd back up in case I run out of gas in the middle of something.

Put your general location in and someone should be able to tell you what LWS in your area is good to deal with.

 

[sns1938]

You are better off finding a shop that does exchanges, that size bottle should be a 20 so no more than an hour or so of weld time.

The good part about doing an exchange rather than getting your bottle refilled is that you are in and out in under 10 minutes and back to your project, most shops do not fill on site and even if they did your bottle would just be placed in the que and you would have to wait days to get it back.

I have 1 bottle that size, it is my 2nd back up in case I run out of gas in the middle of something.

Put your general location in and someone should be able to tell you what LWS in your area is good to deal with.

Oh wow, I didn't realize it'd last so little time. Although, if I can swap it for $20, then I'd be very happy.

Usually, if you swap a bottle (for say $20), and your exchange bottle is out of certification, do they charge you a certification fee on top of the $20?

If I can have a full bottle which is in date, for less than $100 total, then I'm happy enough.

(It does sound like I should go to a 'night school' type place to re-learn how to weld, as I've done less than 10hrs total on MIG and that was all 20 years ago ... I tried recently and I completely ****. If I do a short course, I'd probably cover the course costs with the amount of their gas I use).

Thanks again all,

 

[sns1938]

Oh wow, I didn't realize it'd last so little time. Although, if I can swap it for $20, then I'd be very happy.

Usually, if you swap a bottle (for say $20), and your exchange bottle is out of certification, do they charge you a certification fee on top of the $20?

If I can have a full bottle which is in date, for less than $100 total, then I'm happy enough.

(It does sound like I should go to a 'night school' type place to re-learn how to weld, as I've done less than 10hrs total on MIG and that was all 20 years ago ... I tried recently and I completely ****. If I do a short course, I'd probably cover the course costs with the amount of their gas I use).

Thanks again all,

Just realized you mean 20 cu.ft bottle size, not $20 exchange cost.

Will confirm local exchange price (for an out of date bottle), and if over $40, will just list on Craigslist for someone who is willing to invest more to sort it out, or who has contacts to get it certified/filled cheaper).

Thanks,

(PS am going to the workshop where the bottle is stored today or Sunday, so will take some better photographs then).

 

[MoonRise]

Pretty much covered the points, but I'll chime in anyway.

DOT-3AA2015 is a DOT-rated 3AA high pressure gas cylinder, rated for 2015 psi fill pressure.

Unless there is a more recent date stamp somewhere on the cylinder (they are not always lined up or even in order, the recert facility often stamps the recert date wherever they want), the 03A01+* mark indicates it was last tested and certified for use in March of 2001, the "A" is the cert company ID mark and the + indicates it is acceptable to 'overfill' the cylinder by 10% and the * indicates the cylinder can be retested every 10 years.

The 1686244 is the cylinder serial number.

Your cylinder is (was) filled with C25 (75% argon and 25% CO2, a standard shielding gas for short-circuit transfer mode GMAW) and came from Praxair (a pretty big gas/cylinder company).

Pictures #2, 6, and 7 show the label indicating that the cylinder is 88 ft3 in volume. So, that cylinder is a volume of 80 ft3 when filled 'normally' to 2015 psi, but with the 10% overfill it actually had/has 88 ft3 of compressed gas in it (10% more than 80 is 88 ).

You will not be refilling (exchanging most likely) that cylinder for $20.

That 80 ft3 cylinder when full would usually give you approximately 4 hours of welding time (80 ft3 volume divided by 20 ft3/hr typical shielding gas flow rate = 4 hours of welding time). When filled to 88 ft3 volume, you get approximately 10% more welding time, so 4.4 hours of welding time. Ignoring any leaks and pre-flow and post-flow times.

Oh, that cylinder is steel. 3AA cylinders are steel. Try to stick a magnet to it, it will stick.

An 80 ft3 cylinder is about 7" diameter and about 32 inches tall and weighs about 50 lbs.

https://www.mathesongas.com/industrialgas/pdfs/Industrial-Cylinder-Dimensions.pdf

 

[sns1938]

Pretty much covered the points, but I'll chime in anyway.

DOT-3AA2015 is a DOT-rated 3AA high pressure gas cylinder, rated for 2015 psi fill pressure.

Unless there is a more recent date stamp somewhere on the cylinder (they are not always lined up or even in order, the recert facility often stamps the recert date wherever they want), the 03A01+* mark indicates it was last tested and certified for use in March of 2001, the "A" is the cert company ID mark and the + indicates it is acceptable to 'overfill' the cylinder by 10% and the * indicates the cylinder can be retested every 10 years.

The 1686244 is the cylinder serial number.

Your cylinder is (was) filled with C25 (75% argon and 25% CO2, a standard shielding gas for short-circuit transfer mode GMAW) and came from Praxair (a pretty big gas/cylinder company).

Pictures #2, 6, and 7 show the label indicating that the cylinder is 88 ft3 in volume. So, that cylinder is a volume of 80 ft3 when filled 'normally' to 2015 psi, but with the 10% overfill it actually had/has 88 ft3 of compressed gas in it (10% more than 80 is 88 ).

You will not be refilling (exchanging most likely) that cylinder for $20.

That 80 ft3 cylinder when full would usually give you approximately 4 hours of welding time (80 ft3 volume divided by 20 ft3/hr typical shielding gas flow rate = 4 hours of welding time). When filled to 88 ft3 volume, you get approximately 10% more welding time, so 4.4 hours of welding time. Ignoring any leaks and pre-flow and post-flow times.

Oh, that cylinder is steel. 3AA cylinders are steel. Try to stick a magnet to it, it will stick.

An 80 ft3 cylinder is about 7" diameter and about 32 inches tall and weighs about 50 lbs.

https://www.mathesongas.com/industrialgas/pdfs/Industrial-Cylinder-Dimensions.pdf

Thank you, that's brilliant. 4 hours sounds more useful to me. I've found a praxair location not too far from my house, and am emailing now to ascertain cert+fill vs swap costs.

I thought alloy for the cylinder because it was so lightweight. It still has some pressure in it, if I weigh the tank, would I be able to determine how much gas is left, or is the margin of error on empty tank weight so much that you can't tell if it's 2% to 22% full at the end?

I'll look again at the markings for a re-cert. Would a re-cert have the same format as the 03A01+*? (And given it ran out in Mar 2011, it could be something like 06A12+* if it was re-done in June 2012 at the same place, for example?

 

[tarbellb]

Moonrise is correct with the 4+/- hrs weld time for a 88c/ft bottle.

 

[MoonRise]

Thank you, that's brilliant. 4 hours sounds more useful to me. I've found a praxair location not too far from my house, and am emailing now to ascertain cert+fill vs swap costs.

I thought alloy for the cylinder because it was so lightweight. It still has some pressure in it, if I weigh the tank, would I be able to determine how much gas is left, or is the margin of error on empty tank weight so much that you can't tell if it's 2% to 22% full at the end?

I'll look again at the markings for a re-cert. Would a re-cert have the same format as the 03A01+*? (And given it ran out in Mar 2011, it could be something like 06A12+* if it was re-done in June 2012 at the same place, for example?

Without having the tare weight of your exact cylinder (weight of cylinder when it is empty), you have no way to weigh a full or partially full cylinder and know how much gas is in it.

To find out how much gas is still in the cylinder, just put the pressure gauge on it.

So much easier than trying to figure out the tare weight of the cylinder, then going and weighing a partially filled cylinder, and then (the easy part) subtracting the tare weight from the actual weight of the partially filled cylinder and finding the weight of the gas product in that cylinder.

(a 'full' 2000 psi nominally 80 ft3 cylinder filled with pure argon would have about 9 lbs of argon in it. 1000 psi in that same cylinder would have about 4 lbs of argon in it. Etc.)

Yes, the cylinder recert stamp will be the same format as 03x01, where the "x" is the recert company ID code.

 

[sns1938]

No other markings, apart from this:



Connected the gauges. Now these have me confused. The left seems to indicate that lots of gas was leaving the bottle, but I could hear none. The right didn't move, indicating to me that the bottle has almost no pressure.



Thanks,

Some other images

 

[sns1938]

Just checking another bottle. So this one was certified Nov 08, and is good for 10 years from then? Thanks,