Propane tank volume

Does anyone know the EXACT cubic capacity of air at ambient atmospheric
pressure for a 20# propane tank? That is, a tank that has the valve opened,
then left open until all the contents have gone out, and still has that
empty space. I need to figure out the underwater lifting capacity of one of
these tanks. And yes, I know I should shut the valve.
Steve
Reply to
Steve B
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Since you want the lifting capacity, measure that directly, not round-about with volume, tank weight, & math. Jim was on the right track, if facetiously: water in a trash can & immerse the propane tank. Measure the force required to hold it under. Bathroom scale should be good enough.
KISS!
Bob
Reply to
Bob Engelhardt
Once you get your volume, don't forget you'll get a bit more upthrust if it is in seawater.
Reply to
newshound
Less bouyancy if the tank is made of metal.
Christopher A. Young Learn more about Jesus
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Once you get your volume, don't forget you'll get a bit more upthrust if it is in seawater.
Reply to
Stormin Mormon
Stormin Mormon submitted this idea :
Please explain just a little. What has metal got to do with change in bouancy in sea water?
Reply to
John G
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Reply to
john
New-Never Used- Propane gas cylinders steel 20 pounds capacity With 10 percent valve for overfill protection, Poly safety plug. Quality construction and a durable polyurethane finish. Specifications: Size 6-1/2 inch x 12-3/8 inch x 18-1/16 inch . LP-Gas capacity (approximate gallons) 5, water capacity 47.7 pounds, tare weight 18.5 pounds, cylinder volume 1,323 cubic inches, collar height 4 inch , footing diameter outside 7-13/16 inch . Manufactured in accordance with DOT-4BA-240.
Reply to
john
If the tank is made of metal, it will tend to sink. Thus countering some of the air bouyancy.
Christopher A. Young Learn more about Jesus
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Stormin Mormon submitted this idea :
Please explain just a little. What has metal got to do with change in bouancy in sea water?
Reply to
Stormin Mormon
47.7 pounds capacity (bouyancy) - 18.5 pounds of steel weight, = 29.2 pounds lift. Of course, there are some other factors, but they are minor.
Christopher A. Young Learn more about Jesus
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"john" wrote in message
water capacity 47.7 pounds, tare weight 18.5 pounds,
Reply to
Stormin Mormon
In water the steel weights less. You have to figure the volume of the steel and then add the weight of water for that volume.
John
Reply to
john
Steel's density is 7.85, roughly 8, so the buoyancy is the weight of water the tank can hold minus ~7/8 of the empty weight.
jsw
Reply to
Jim Wilkins
That's about what I would have said.
Christopher A. Young Learn more about Jesus
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Storm> 47.7 pounds capacity (bouyancy) - 18.5 pounds of steel weight, = 29.2
In water the steel weights less. You have to figure the volume of the steel and then add the weight of water for that volume.
John
Reply to
Stormin Mormon

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