Hello fellow airguners wanted to but together a small video on air tanks, filling and safety.
Thanks again !
Thanks again !
Air Tank Explosions and Safety In Filling
- Thread starter Shooting Targets
- Start date
Cool video. For anyone interested, that may keep full tanks in their hot car, here is some math.
According to this
www.scottsfortcollinsauto.com
A car reaches around 138F peak when 90F outside. Using those delta's you can calculate the new pressure from a tank filled to 4500 psi at 90F sitting in your car that raises the tank temperature to 138F as...
138 *5/9+273.15 = 349.8 Kelvin
4500 / ( 90 * 5/9*273.15) = 6.498
6.498 * 349.8 = 4871 psi
To bring that final number down to 4500 psi peak you would want to keep your tank fills below 4160 PSI.
138 *5/9+273.15 = 349.8 Kelvin
4160 / ( 90 * 5/9*273.15) = 6.498
6.498 * 349.8 = 4503 psi
According to this
How Hot Do Cars Get in the Summer? - Scott's Auto
As things start to heat up in Northern Colorado, you may notice that the interior of your car feels extremely hot after being parked out in the sun for a while. Your only thought when you get inside is to roll down the windows and crank up the AC to cool things off as fast […]
www.scottsfortcollinsauto.com A car reaches around 138F peak when 90F outside. Using those delta's you can calculate the new pressure from a tank filled to 4500 psi at 90F sitting in your car that raises the tank temperature to 138F as...
138 *5/9+273.15 = 349.8 Kelvin
4500 / ( 90 * 5/9*273.15) = 6.498
6.498 * 349.8 = 4871 psi
To bring that final number down to 4500 psi peak you would want to keep your tank fills below 4160 PSI.
138 *5/9+273.15 = 349.8 Kelvin
4160 / ( 90 * 5/9*273.15) = 6.498
6.498 * 349.8 = 4503 psi
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Yea, going to trust you on this... either way makes sense not to leave the items in a car... Thanks for watching...Cool video. For anyone interested, that may keep full tanks in their hot car, here is some math.
According to this
How Hot Do Cars Get in the Summer? - Scott's Auto
As things start to heat up in Northern Colorado, you may notice that the interior of your car feels extremely hot after being parked out in the sun for a while. Your only thought when you get inside is to roll down the windows and crank up the AC to cool things off as fast […]
A car reaches around 138F peak when 90F outside. Using those delta's you can calculate the new pressure from a tank filled to 4500 psi at 90F sitting in your car that raises the tank temperature to 138F as...
138 *5/9+273.15 = 349.8 Kelvin
4500 / ( 90 * 5/9*273.15) = 6.498
6.498 * 349.8 = 4871 psi
To bring that final number down to 4500 psi peak you would want to keep your tank fills below 4160 PSI.
138 *5/9+273.15 = 349.8 Kelvin
4160 / ( 90 * 5/9*273.15) = 6.498
6.498 * 349.8 = 4503 psi
Upvote 0
The math checks out.
Using 305.4K rising to 332.04K, 4500psi goes to 4893psi.
This is within the margins of safety on the tank hydro test but very little margin to spare.
Fortunately I fill my tank to 4300max to avoid overtaxing my compressor. The added temperature tolerance is a bonus.
Using 305.4K rising to 332.04K, 4500psi goes to 4893psi.
This is within the margins of safety on the tank hydro test but very little margin to spare.
Fortunately I fill my tank to 4300max to avoid overtaxing my compressor. The added temperature tolerance is a bonus.
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I’m pretty sure these bottles are worn into burning buildings, I better warn my firefighter brother!
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Those tanks are tested above double pressure when hydro testing. An extra 300psi is fine by me. My large scba tank does not have a burst disk but my smaller one does and its set at 6,000psi. Im sure the tanks can handle it just fine. Id be more worried if filled and thrown in a fire! Safety is fine, no hurt in being cautious either.
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Very Good Point..so many things to take into consideration... Thanks for noting that one is pretty obvious.
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The sub zero temperatures is way more concerning to me than the heat. Cold Temps make the resin matrix very brittle plus the aluminum liner will contract possibly causing it to tear because it does to not have the support of the carbon fiber layers. Carbon fiber has a very low cte or coefficient of expansion as compared to aluminum. I've tested to failure composites from -75f all the way up to 550f. Carbon fiber does not have a problem with work hardening but aluminum does. Being made for fire fighting I'll assume that the resin system they have to use is up for the high temperatures. By the way, carbon fiber starts out as a acrilic yard and in the process to turn it into carbon fiber sees 1800f.
Forgot to mention, UV rays will start to break down some resin systems so try and keep the tanks out of direct sunlight if possible.
Forgot to mention, UV rays will start to break down some resin systems so try and keep the tanks out of direct sunlight if possible.
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I’d hope these SCBA tanks are not rated to fail and rupture anywhere close to the recommended max fill rating.
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SCBAs by design do not fail catastrophically, we use them to fill PCPs.
Rescue personnel and firefighters wear them on their backs!
So by design they do not go 
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Are there any repositories of failure data?SCBAs by design do not fail catastrophically, we use them to fill PCPs.
I would imagine the failures typically are just slow leaks, rather than Hollywood-style "explosion as the hero walks away from a burning building" events.
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I believe you imagined correctly… a non issue for how we in the PCP world use SCBAs. Something else down the line would fail first. I don’t believe there are “any” HPA compressors you could use at home capable of rupturing, let alone blowing up an SCBA.
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I have had a Carbon fiber tank fail, The bands let loose and it lets air out very slow, No boom.
I think safety wise just don't shoot your tank,
Do not fill a gallon (plastic) milk jug with gasoline and put two candles in front and two in the rear and shoot it with a 30-06 stupid is as stupid does,
Mike
I think safety wise just don't shoot your tank,
Do not fill a gallon (plastic) milk jug with gasoline and put two candles in front and two in the rear and shoot it with a 30-06 stupid is as stupid does,
Mike
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I think I remember someone taking a scba tank up to 15000 psi before it failed catastrophically. It did go boom but at that pressure....... As I already wrote in the sub thread carbon fiber is way stronger in tension than in compression. I believe for safety, things are designed for 3x the required strength needed.
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Additionally, they had to seal and remove the burst disk. Otherwise the disk would blow out at a much lower pressure than it took to destroy the tank by over pressurizing it.
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