"Intrepid" wrote in message
...


Hi all,

In the maintenance shop at the plant where I work, the machinist has
a device mounted beside the milling machine that directs a blast of
cold air onto the toolbit\workpiece. At the opposite end of this
gadget, you can feel low pressure warm air coming out.

The label on the device is long gone, and he didn't know much about
it, other than it works and is fantastically cleaner than using oil
for cooling\lubing.

Does anyone here know anything about these devices? Like where a
person could get one, how much they cost, what their limitations are,
etc.?

There was no power source attached to it, so it doesn't use
electricity. I couldn't see any kind of oil resevoir on it either.

I've just never heard of such a thing before, and it's got me curious
as hell :=)


Intrepid

They are called vortex tubes. I made one from a Popular Science article back
in the 60's. The cold end gets so cold that frost will build up on the brass
tube, and the hot end can get hot enough that you don't want to touch it.

Do a google search on "vortex tube" and you should get lots of information.
I know there are plans to make your own as well as commercially produced
ones.

Here is one link that gives a good overview.

http://www.visi.com/~darus/hilsch/

Lane