cheap tank

[timinator]

hi everyone,
i am interested in getting a really cheap 80cu ft or larger air tank. i am not using it for diving, but just for a science fair project which requires highly pressurized air in a realatively large amount. price is of prime importance here, and the tank does not have to be diveworthy. just wondering if anyone would know where to pick something like this up for cheap. oh yeah, it does have to be able to hold around 200-300 bar of pressure (around 3000 or 4000 psi i think)

thanks!

btw. i dont know much about scuba diving, so if i said something absurd or something, dont hesitate to tell me

 

[Don Burke]

timinator once bubbled...
hi everyone,
i am interested in getting a really cheap 80cu ft or larger air tank. i am not using it for diving, but just for a science fair project which requires highly pressurized air in a realatively large amount. price is of prime importance here, and the tank does not have to be diveworthy. just wondering if anyone would know where to pick something like this up for cheap. oh yeah, it does have to be able to hold around 200-300 bar of pressure (around 3000 or 4000 psi i think)

thanks!

btw. i dont know much about scuba diving, so if i said something absurd or something, dont hesitate to tell me

Probably the easiest way would be to convince a diver to help you with your project and loan you a tank.

If it were me, I wouldn't let you run off unsupervised with one of my tanks, but I'd help you get the project done.

 

[timinator]

i have an industrial air systems enginner to aid in the actuall design of the project, so hopefully nothing will explode etc (famous last words)

don burke:
isnt there anywhere that divers send retired or beat down tanks when they are, well, whatever happens to tanks when they cant be used by divers anymore but still hold pressure?

thanks!

 

[Don Burke]

timinator once bubbled...
i have an industrial air systems enginner to aid in the actuall design of the project, so hopefully nothing will explode etc (famous last words)

don burke:
isnt there anywhere that divers send retired or beat down tanks when they are, well, whatever happens to tanks when they cant be used by divers anymore but still hold pressure?

thanks!

You can rent an air tank from an industrial gas supply house. It won't be a dive tank, but will have a CGA fitting your engineer will be able to work with. BOC is the outfit I deal with for such things. They are international, so you may have one of their facilities near you.

Taking tanks underwater is about the safest thing we do with them. They are retired when they aren't safe to hold pressure and not before.

I've worked with engineers before. If it was my tank, I'd still be there any time the system was charged.

 

[pasley]

timinator once bubbled...
...isnt there anywhere that divers send retired or beat down tanks when they are, well, whatever happens to tanks when they cant be used by divers anymore but still hold pressure?
thanks!

When they are no longer suitable for diving, they are no longer suitable for to hold air under presure, particularly 3000 psi or higher. That is why they are comdemed. If they were still safe to presureize to 3000 psi, they would still be divable tanks. The tanks that cannot pass inspection are destroyed.

This is not a little bit of pressure that if the tank fails will be like a balloon poping. When these tanks let go, it can kill people and destroy stuff. See below sites for pitures of the damage a tank can do when it fails:
http://www.diveshop-pr.com/pages.dir/engl.dir/tankexplosion.html The car here is quite torn apart, and only part of the bottom of the tank cam apart.

http://www.scubabomb.freeservers.com/ Destroyed the dive shop and took of part of his hand.

Best bet is to rent a tank from an industrial air supplier or get a diver to help with the project and loan you a tank.

Where are you located?

 

[Don Burke]

Maybe that little voice in my head that keeps whispering "paintball" and "potato gun" would shut up if I heard a little more about the project.

Maybe not.

 

[snapperd1]

The paintball option is a good one. You can get air tanks from the paintball shop that will hold the 3000 - 4500 PSI. You may be able to rent one from them. Look in the phone book for a local shop.

Good Luck,

TD

 

[cstreu1026]

Just to give you another idea of what can happen to a cylinder of compressed gas:

http://www.healthyhome.net/nitrousexpress.htm

Of course in my opinion it was more the owner's fault than the manufacturer or vendor's.

 

[CBulla]

Just a thought, and I don't know where you live timinator, but if its near water, check pawn shops. I've found tanks in good condition in those places. Infact, one I dive with regularly was bought for $25.. Had it checked at the shop, new O-ring put in, viola, rockin tank!

 

[timinator]

the project consists of an old 4-hp ride behind lawn mower being converted to a compressed air engine, ie pressure release from tank pushes piston instead of gaseous explosion. but now that you mention paintballs and potato guns.......

anyway, about the paintball tanks, how much air do they hold?

i live in the middle of pennsylvania, in lancaster (not amish.....), so finding a pawn shop with tanks would probably be tough, but its a good idea

those are some wicked explosion pictures! (note to self: have someone else test it the first run)