Anyone Ever Built an Air Tank?

[justinp61]

I've found a 80 gallon tank locally. All I have to do now is fab up the mount for the compressor and motor and plumb it all up. The new motor should be here Monday, so hopefully I'll have it running next week. I know full well the dangers of air tanks, a neighbor of mine lost one of his legs from the knee down from a failure. Unfortunately he just happend to be walking by when it failed, yes it was a factory made tank. I'd never seen anyone build their own tank, that's why I asked here. The ends were something I was not sure of, hence the original post. There are people on here with far more experience than I have, or will ever have. There was no intention on my part to cobble something out of scrap. I am very capable of building it and doing a good job at it. I have a street/strip 69 Dart that runs low 7.20s at 95 mph in the 1/8 mile that I did all of the fab work on, so I trust my work. If I was not confident in my skills i would never even consider tackling such a job. Thanks to all of you that offered useful information .

[kcstott]

Justin
Well said. And I'm not here to tell anyone what they should do either. Just pass along my experience and hope I help someone out.
If I had a nickel for every time someone told me I can't do something or I should leave it to a "professional" I'd have enough money to pay someone else to do it.
Things that I've done that most would not attempt or should not attempt.
(Keep in mind I'm talking about the general public, not people that post here)
rebuilt my first truck engine at 18 rebuilt my motorcycle engine at 20, i was already reloading ammo for a few guns at the time too. Rebuilt the diff in my jeep at 25, Learned how and did anodizing in my garage for four years for real paying customers, Rebuilt a few rifles i.e. stocks and barrels including setting the head space. And just in general fixed what was broke improved what needed improving Fabed, welded, and machined anything i needed all with little help from anyone.
I'm not boasting what I'm saying is if you are skilled and fully understand all the intricacies involved with a project then by all means have at it.
But do the research first and find out if there is something you're missing.
you'll be a better person for it and keep all your fingers too.
Kerry

[lanceman73]

Listen, I've made my own 30 gal. tanks out of 3 11 gal. tanks. I agree that the chinese products are inferrior. To buy a tank though, is almost unaffordable. I was quoted $1500.00 per tank for what I made for about $300.
Thanks,
Lance

[Anti-GMAW]

As far as I'm concerned the ASME cert. tags on most compreors are for liability purposes. I'd trust some of the farmer welds my dad makes before some of those chinese tanks. At work some pressure vesseles don't even require ultra sound or X-ray testing and they hold as much as 2,500psi. However, They are engineared with about as much overkill as a WW2 Tiger tank. I think the highest any of ou'r vessels get to is usualy around 4,500psi.


Here's a small one:


http://i162.photobucket.com/albums/t...Picture063.jpg

[justinp61]

anti-GMAW, I think the tank in you're photo would hold enough air for me. It would wear my compressor out filling it though.

[Synchroman]

Buy a tank. You'll live longer!

I certainly agree. Furthermore, when you do buy your tank, make sure that it is marked with an "ASME" tag. I have an 80 gallon vertical air compressor with an ASME tank and I wouldn't want to be anywhere near it if it ever blows. An ASME certification is worth more than mere talk. It signifies that the tank was built and tested to a known specificaton and that it is safe for the use intended.

My tank is abut 15 years old and it was made in USA.

Assuming an operating pressure of 150 psi, that's going to amount to a lot of pressure on each square foot.

It's more than merely being able to fabricate and weld the tank. It's the material you would use and the necessary hydrostatic testing after it's "done".

Uh-uh. That's not a job I'd tackle. There are certified tanks available from places like MCS and Grainger. That would be my course of action.

Gutless in Sacramento.

[grnxrymnky]

check out ebay item number 130220533358

now that's an air tank

[kcstott]

check out ebay item number 130220533358

now that's an air tank

I installed a tank like that at my old day job. But the guy selling is a wee bit off on his math. It's about 500 gallons not 900.

[superredd]

Has anyone used propane cylinders as a cheap alternative to buying airtanks? for example you could get a 100lb propane cylinder and rig it for an extra air resevoir on your trailer or in your shop or something?? i've always thought of this and was told there was a safety factor of 3 or something built into the tanks.. not quite sure but a full cylinder yeilds 100 psi abouts last time i checked. What do you guys think?

[platypus20]

An 80 gallon air tank holds 80 gallon at zero psig , at 150 psi that 80 gallon tank in really holding the equivent of 896 gallons of air at atomospheric pressure, because of the density of the compressed air. If you use the formula to figure density, this explains why a 220 cuft gas cylinder, is small enough to carry, as a cubic foot of air is the air volume in 3' x 3' x 3' box at atomospheric pressure. As the pressure goes up the stored air is actually engergy, trying to uncompress itself.

cylinder or tank pressure + 14.7 / 14.7 = density factor

using the 80 gal tank at 150psi

150psi +14.7 = 164.7 / 14.7 = 11.2 density factor
80 gal x 11.2 = 896 gallons




example a 220 cuft oxygen cylinder at 2200 psi

2200 + 14.7 = 2214.7 / 14.7 = 150.6 density factor

220 cuft / 150.6 = 1.4 cuft the actual capacity of the cylinder at atomospheric pressure.

Jack