is my liquid oxygen tank leaking?

[minority]

ok so I go to work today and turn my oxygen tank on and notice its completely out, I havent been to work in about a week and when I left I had at least 1/4 of my tank and made sure it was completely closed. I noticed early on when I got the tank it sounded like it was leaking but they said it was normal. When I work in the cold sometimes the top frosts over but the company said that was normal as well. Im calling nexair tomorrow and telling them if they dont do something there about to lose a customer. I would like your opinions on liquid tanks as well I think im about to switch back to my small tanks.

[2wheeler]

sounds fishy to me...

[JDNACEglass]

liquid tanks vent when you dont use them, and a week for 1/4 tank to vent off when not being used seems about right. liquid is far more economical, even if 1/4 of your tank vents unless u are paying alot for one, i was getting mine for 119 delivered, i moved and the tacked an extra 50 for delivery on, and if i only got 3/4 of a tank, still much cheaper than k tanks without the hassle. sometimes they will deliver one that vents from delivery, and if you open the vent valve and get the psi down to around 150, and then it keeps rising when you close the valve, might be a bad tank, they always bring me a new one when i tell them about it, it seems to me its probably chepaer for them to eat the cost of a tank than go and test each tank to make sure they are working properly. thats the only downside with them really, they vent when you dont use them, and it seems every tank is different in how fast they vent off

[2wheeler]

Maybe I'm wrong, but wouldn't your tank still have 230-350psi when you showed back up at the shop if it all vented out? I've got two tanks and I try to completely drain them before refilling. I usually rock about 80psi off the tank, but I'll chill on the lathe with my national and make parts until the oxygen goes down slowly. Took an hour the other day to go from 40psi down to 30psi.

[minority]

I have a nortel red max and talked to mr nortel himself and he told me to keep the psi around 8-10 so thats what I do, it just seems funny to me because Ive never had an issue with returning to my tank and seeing it lost oxygen, there again im usually at my shop every day or two. Im paying $200 for this monster plus $40 a month to rent it so i feel like i got screwed out of $50

[somewhere]

First question I have is how did you measure what was left in the tank?

[minority]

its the little ball in the cylinder on the top middle of the tank

[2wheeler]

Oh man... you were prob empty already.

[JDNACEglass]

i never trust the gauge on the tank, i always rock the tank to just feel the weight to judge how much is in there

[somewhere]

The only way to really know what's in the dewar is to have it sitting on a scale.


The contents gauge on liquid oxygen tanks are never accurate.

[minority]

I see what your saying about it never being accurate but I mean it seemed like a pretty big chunk, 1/4 was being generous it was a little less than half the tank and now its bone dry, no way Im paying $250 for that.

[somewhere]

You let a liquid oxygen tank sit for a week I can't see how you can blame anyone. Dewar tanks need attention if not being used. The oxygen is constantly turning from a liquid to a gas. The head pressure builds and it vents off. The longer it sits the more you lose.

It is very possible that as it was building pressure and venting it froze the vent open and you lost a substantial amount of oxygen.

Either way my welding shop wouldn't dream of refunding me money for a tank I left unattended unused for a week. If I was there and it was faulty they would happily replace the tank but there is no way you can prove the tank was faulty.

Bottom line is you don't know how much was in the tank when you left. You can speculate but you have no way of knowing for sure. How long did you have the tank before leaving it for a week?

[minority]

I could see how that makes since, I was using it for a little over a month with no problems. I called nexair and they said its not there problem because they delivered a full tank. Either way im done with liquid if its like that, Im going back to my small tanks.

[somewhere]

I don't know how much you work but if you can get a solid month out of a liquid tank I can't see how going to high pressure cylinders will be any better. Either way I'm sure you can do the math.

I would be delighted to get a month out of a dewar.

[hashmasta-kut]

i usually get a month working some every day, anywhere from 4-10 hours.

[minority]

well this is my fist time buying a full liquid tank so I didnt know too much about it. I used to buy the small 4 ft bottles for $20 and even those guys would last me a week or two. I actually went to nexair last week and they told me the really thick 6 ft tanks are only 57 cents more, so thats twice the amount of oxygen for 57 cents and those will easily last me a month. They told me the reason its like that is because the small tanks are so rare and the big thick ones are so common they can price them the same, didnt know if anyone knew that but Ive been blowing glass for over a year and just found that out. with that being said liquid oxygen can daralick my balls.

[Shattered Dreams]

what tank will last you a month? I want one.
a k tank lasts me 2-3 days if im working, at 25 each.
how can that compare to liquid?
I think its like 16 k tanks per dewar.

[minority]

those guys in the back will last me a month, $20 a month to rent and $20.57 to fill it up. I work 5 days a week 5 hours a day, better than paying $200 for liquid and $40 for rent...I just dont get the whole liquid thing, doesnt seem cheaper to me.

[Shattered Dreams]

hard to tell size from the pic, is it something other than a k or t tank?

I thought the largest they made is like 330cf, and a k is 250?

if you have a larger torch you can work faster, but you use a lot more gases.
liquid gives you more oxygen for the cost, just need to put it to use and not let it go to waste.

[The Goat]

If a 320cf or less tank last a week. Liquid is a bad choice for you. I can burn through a 330 In a day on my redmax if I'm doing iso. How you get any size to last like that is a puzzle to me. The oxy bottle of plenty. Lol