Oxygen tank storage during summer travels

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TrueCourse

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TrueCourse
For those using portable oxygen tanks during the summer months when the surface/airport ramp temps get very hot, do you keep the tank/cylinder in the closed up aircraft all the time when traveling or do you remove them and store them in a cooler location? I’ve read some guidance on removing them for safety reasons, but how different is leaving the tank in the cabin versus a built in system that always remains in the airplane? Other than direct sunlight where the exposed tank temp may got hotter than a hidden tank, is there another reason? I prefer to lean towards being conservative and removing it, but would this be overkill?
 
Not a issue with temps it might see in a car or plane. Besides, there is a physical pressure burst disk that will pop long before the burst pressure. That’s why you want to get your cylinder visually inspected annually in addition to the 5 year hydro.
 
You can determine if it’s a hazard pretty easily. Find the MAWP for the tank, this will be the maximum pressure that the tank is rated to withstand and should be written on it somewhere. Next, find the current temperature and pressure in the tank. Then, go to this website: https://webbook.nist.gov/chemistry/fluid/

Now, select oxygen as the species and choose the units you plan to work in. Select isothermal properties. Next, press the continue button and enter the temperature. Put “P low” a bit lower than the pressure you measured, and “P high” a bit higher. Set the pressure increment pretty low, maybe around 0.1. Press for data. Find the volume that corresponds with your measured pressure. Remember that value. Now go back to the first screen and choose isothermal properties again, and set the highest temperature you think it might get to inside your plane. Repeat the same steps for this new temperature but set “P high” to the MAWP of the tank. Leave “P low” as your original measured pressure. Now with the data it gives you you should find the point with the same volume as before. That will correspond with the pressure at the higher temperature. That should be lower than the MAWP. The amount of extra pressure it can handle will probably be very large.

After writing all that, it’s maybe not as easy as it feels to me. But that should at least give you an idea of how we design pressure vessels. There should be a pretty big margin of safety. I wouldn’t be too worried.
 
It’s fine in the airplane. Otherwise installed O2 bottles would have to be removed too! From the ideal gas law, pressure goes up (very) roughly by 10%-15% from 70 deg to 140 deg.
 
The bottles are filled nowhere near to their failure pressure, so you have a lot of leeway.
 
Mine is sorta-perma installed in the rear of my plane. Piper has no instructions to remove it in hot weather.

It lives nowhere near the failure zone according to several that I have talked to in the industry.
 
Do O2 tanks have over-pressure burst discs? I know scuba tanks do, and if they're heated so that the pressure rises above some limit the disc will rupture and vent the tank.
 
They do have a rupture disk. Set for 3,000 psi….I doubt that kind of desert temperature will burst it.
Half Fast said:
Do O2 tanks have over-pressure burst discs? I know scuba tanks do, and if they're heated so that the pressure rises above some limit the disc will rupture and vent the tank.
Click to expand...
 
Checkout_my_Six said:
They do have a rupture disk. Set for 3,000 psi….I doubt that kind of desert temperature will burst it.
Click to expand...


Then I guess I don't see any concern here. It's very unlikely that a tank would get hot enough to be a problem, and even if it did the only risk would be losing a tankful of O2.
 
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As long as there is no spark.

Also, if your tank ever vents out in the plane, you need to air it out well. The oxygen can soak into fabrics and increase flammability.
 
Hoping you are being sarcastic. The vented o2 will simply disperse into the atmosphere.
 
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