bczygan
Well-known member
Guy sold me a Helium tank like you use to blow up balloons for a party with. He had put on a valve, a gauge and a hose. Anyone do this? Safe? What pressure to use?
Helium Tank as Portable Air Tank
- Thread starter bczygan
- Start date
Jim Johnstone
Well-known member
Put up a picture, especially if you can find some stampings on the shoulder. Industrial helium cylinders are usually rated for 2015psi, but yours may not be industrial cylinders.
If it happens to be an industrial cylinder, all the info you need to know will be stamped on the shoulder. Get me a pic of that info and I can tell you what it means.
If it happens to be an industrial cylinder, all the info you need to know will be stamped on the shoulder. Get me a pic of that info and I can tell you what it means.
Outlawmws
Well-known member
It works but the conversion is a pain in the ***. It is also not legal to convert those tanks for use with pressurized air. (So if someone is injured you would be held liable...)
The working pressure of the portable tanks is about 275 psi. what you are willing to risk is up to you...
The working pressure of the portable tanks is about 275 psi. what you are willing to risk is up to you...
Outlawmws
Well-known member
He does not have an industrial cylinder so those pressures are not safe...
Jim Johnstone
Well-known member
Can you put a pic up of what type of helium tank he is talking about?
Outlawmws
Well-known member
That's the one I was thinking. and yeah 120 sounds about right. I just don't like that type of tank for air much, They are SO lightweight, and have that damn blow plug. It would not take much to rust through one of those...
Also those handles are also supposed to act as a guard for the valve to prevent it's being knocked off, and they are just not up to it in a garage environment.
Also those handles are also supposed to act as a guard for the valve to prevent it's being knocked off, and they are just not up to it in a garage environment.
Jim Johnstone
Well-known member
Ahhh I see. I was picturing a small welding style helium tank like you can buy at TSC stores up here. I wouldn't waste my time with one of those things considering how cheaply you can buy an air pig.
tbobbo
Banned
I have seen it done with old a/c 134 freon bottles, looks similar to that......................but I would not touch it! Even the cheap tire tanks are heavier built than that, if that tells you anything.
Come to think of it, I think the guy built one out of a freon tank as well. Yeah... I remember now.. a green DuPont tank.
RangerDaleXp
Well-known member
I have not use those, but I did convert a couple of propane takes to use as air tanks. You need to wash them out though or the air smells like propane that comes out of them all the time.
G_P
Well-known member
I have a couple of the freon tanks I picked up when they installed some new coolers at a supermarket.
I removed the **** plastic valve that was on them and drilled/tapped the fitting in the tank to 1/4" pipe thread.
They have been in use for over 10 years with zero issues being pumped up to 120 or so PSI. I would not trust them on a dual stage compressor pushing 175psi though.
Propane tanks work great too but they are heavy as hell and getting the propane odorant out of them is a PITA
I removed the **** plastic valve that was on them and drilled/tapped the fitting in the tank to 1/4" pipe thread.
They have been in use for over 10 years with zero issues being pumped up to 120 or so PSI. I would not trust them on a dual stage compressor pushing 175psi though.
Propane tanks work great too but they are heavy as hell and getting the propane odorant out of them is a PITA
I have a friend who was a career chemist working in a lab that gave me an air tank made from a helium tank a long time ago.
It resembled a 1/3 size propane tank but very light.
He was very meticulous so I didn't have any doubts about it's safety BUT it may very well have been something special for the lab setting.
I didn't use it much and now I really regret throwing it out because I have a need now and a converted propane tank is anything but portable to me. And he is retired so boo hoo. I wouldn't trust an import air tank without a safety standard listing .
It resembled a 1/3 size propane tank but very light.
He was very meticulous so I didn't have any doubts about it's safety BUT it may very well have been something special for the lab setting.
I didn't use it much and now I really regret throwing it out because I have a need now and a converted propane tank is anything but portable to me. And he is retired so boo hoo. I wouldn't trust an import air tank without a safety standard listing .
Outlawmws
Well-known member
helium tanks have a built in pop off in the tank so if they do over pressure it pops & bleeds off.
the . yes the metal is thin, and that would be a concern when it starts to rust . I am pretty sure they are thicker than the 1lp propane cylinders are , based on having cut both open and ( my memory)
the . yes the metal is thin, and that would be a concern when it starts to rust . I am pretty sure they are thicker than the 1lp propane cylinders are , based on having cut both open and ( my memory)
rust in the eye
Well-known member
Why all the hand wringing? Don't these carry higher(than 125 or so) pressure when filled w helium?
Don't they have the relief "plug" on them?
I don't think the failure mode would be explosive anyway. Correct me if I'm wrong.
Don't they have the relief "plug" on them?
I don't think the failure mode would be explosive anyway. Correct me if I'm wrong.
Outlawmws
Well-known member
Google "compressor tank explosions" then switch to images...
rust in the eye
Well-known member
Yikes!!
Seems rust is the cause for this.
Outlawmws
Well-known member
Not just rust. Fatigue also; but also, inappropriate materials. PVC for you air lines? Not a good idea! Copper, or steel, yes.
PVC when it breaks, it shatters, and you get some really deadly shrapnel with razor sharp edges.
This is why pressure testing is done by filling with water, then adding pressure; if it does fail, the water. being uncompressible, instantly drops the pressure. Air and other gasses compress and store energy just like compressing a spring.
PVC when it breaks, it shatters, and you get some really deadly shrapnel with razor sharp edges.
This is why pressure testing is done by filling with water, then adding pressure; if it does fail, the water. being uncompressible, instantly drops the pressure. Air and other gasses compress and store energy just like compressing a spring.
Naw…just make sure you video it…wanna see if flight is one of the many possibilities that could occur.
Outlawmws
Well-known member
"Hold mah Beer! I'm a gonna trah sumpin!"
nadogail
Well-known member
I would "Proof Test It" at a multiple of my planned operating pressure then operate it at about half of the proof test pressure.
My first compressor was built with an Automotive Air Conditioner compressor and two discarded refrigerant tanks, the motor came from a washing machine.
My first compressor was built with an Automotive Air Conditioner compressor and two discarded refrigerant tanks, the motor came from a washing machine.
LopezBart
Well-known member
If you want to make a portable air tank for use with 150 psi or so, there are lots of grill tanks kicking around. After removing the valve from a cylinder w/o external rust, check for rust inside (unlikely). Fit a cross, schrader valve, $10 air pressure relief valve and an quick release air fitting for attaching a hose.
These tanks are relatively sturdy since they need to withstand 300 psi (over temperature propane pressure climbs quickly). When they develop rust or other signs of wear, find another tank and transfer your fittings. Note that these tanks have a finite life.
You can use bleach to react with the mercaptan (odorizer) in the tank; leave the tank open when treating the tank. I'd treat the drainage as hazmat as chlorinated hydrocarbons can be nasty.
These tanks are relatively sturdy since they need to withstand 300 psi (over temperature propane pressure climbs quickly). When they develop rust or other signs of wear, find another tank and transfer your fittings. Note that these tanks have a finite life.
You can use bleach to react with the mercaptan (odorizer) in the tank; leave the tank open when treating the tank. I'd treat the drainage as hazmat as chlorinated hydrocarbons can be nasty.
Aaron_W
Well-known member
That would be my main concern. They are very light because they are made for a single use and contain an inert gas. Repurposing the tank adds numerous new stresses, multiple refilling cycles, rust, wear and tear all well outside the conditions expected when it was engineered to hold helium, transport to the store and then recycled after use.
The phrase bare minimum comes to mind.
Aaron_W
Well-known member
Just had a look, portable 5 gallon air tanks rated at 125psi can be had for as little as $40 to upwards of $120 for a quality name brand. I'm all for saving money but a pressure vessel is not an area I want to be cutting corners.
Beerhippie
Well-known member
Just throwing some **** into the scrap metal bin here and I notice someone has tossed a very good-condition "hot-dog" jobsite compressor in the bin. I'm sure the piston/cylinder went bad and the tanks are still fine. If I didn't own a nice little pancake comp, I'd make a portable tank from those.
Considering how short the jobsite life on most "oilless" comps is, I'm sure you can find a trashed one with perfectly good tank(s) for free.
If you want the one from our bin, come and get it.
Considering how short the jobsite life on most "oilless" comps is, I'm sure you can find a trashed one with perfectly good tank(s) for free.
If you want the one from our bin, come and get it.
alfadan
Well-known member
OP is from 2012 in case anyone is waiting for a response.