Coolant tank materials

Ok... I have cobbled together an idea in my mind for a pressurized coolant system with relatively easy recovery. Two tanks. One is a pressurized tank for coolant with a pickup near the bottom of the tank. (Also a large drain for flushing). The other is a collection tank for run off from the machine. A large filter assemble keeps chips out of the recovery tank. When the recovery tank starts to get full you close a valve from the filter, open a valve to the pressure vessel, and the pressure equalizes allowing the collected lubricant to flow into the pressure tank. When done just reverse. Close the valve between the tanks and slowly open the one from the filter.

A little crude experimentation has shown that relatively low pressure and volume is needed to work a rig like this.

You do not even need a fill port on the pressure tank when coolant runs low. Just pour it into the recovery tank. Air pressure does the work. My thoughts are that with pure oil based lubricant coolants (can't use a water based on my mill) there is no risk of ignition. No vapor or mist with a liquid stream, and no potential ignition source as part of the coolant system like a pump motor.

My concerns are what materials easily at hand to use for the tanks. Obviously would need to be impervious to oil, and other petroleum distillates and water displacers. Also, not likely to fail catastrophically. I'm thinking aluminum or steel. I would be open to other ideas for materials. I would probably have to make the tanks to size and area available.

I know I am probably re-inventing the wheel here, but it's a fun mental exercise if nothing else.

Reply to
Bob La Londe
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A couple of scrap fire extinguishers?

Mark Rand RTFM

Reply to
Mark Rand

That is not a horrible idea at all. Heck they are cheap enough these days for the small ones that I could just waste a couple. I'll have to study how the heads go on and see if there are any elegant applications there.

Reply to
Bob La Londe

look at "pressure bleeder" for cars, you can buy this already made

Reply to
Bill Noble

How big do you want the tanks? What about propane tanks? Either the

5 gallon ones or the little disposable tanks.

The five gallon propane tanks have valves that screw into a standard pipe thread.

=20 Dan

Reply to

I was think gallon and a half for the pressure tank and about a gallon for the recover tank.

Not a bad idea. They can certainly stand the pressure if you can get all the goo out of them.

And there are plenty of them around with the old style valves cheap enough. However, I have never figured out a way one of us ordinary guys can get the stupid valve out.

A little small, but maybe workable gotta think about it. Initially I'll want the whol thing small enough I can move it between my lathe and my mill. If it works I would build two of them.

If you can get the old valve out.

Reply to
Bob La Londe

Maybe the disposable helium or freon tanks.

Reply to

It can be done. I have made air tanks out of a couple of propane tanks.

But for the size you want, you might be able to find a couple of stainless steel garden sprayers that are used for spraying weed killer.


Reply to

The trick is neutralizing the methyl mercaptan (sulfur compound) stink without having every homeowner within five miles calling the Fire Department screaming "Gas leak! Big One! Get out here!!!"

(Can also be Ethyl Mercaptan or Butyl Mercaptan...)

Hydrogen peroxide and chlorine bleach are supposed to neutralize mercaptans - but not both at the same time... Don't let it spill into the earth, or the stink can persist for months.

Big open end wrench to the square boss on the base of the valve, make your own out of plate with "flare wrench" tangs at the open end to grip all four corners - it's brass, it will round off in a heartbeat if you don't. I saw a factory wrench at one propane dealer (probably from the valve supplier) another one made his own.

And you make a big Chain Wrench out of a chain binder to hold the tank steady to a post. It's standard 3/4" NPT, IIRC.

You can get weld-on tank bungs from McMaster Carr - you'll need a few

3/4" bungs for the bottom of the top tank to fill into the second, and then other 3/4" bungs for the "outlet" and "drain".

And a few smaller ones, 1/4" or 3/8" for the "air fill" and "air vent" for both tanks. If you want to rig a level sight glass, two weld bung fittings, two 90-degree tube X NPT fittings, and some clear polyethylene tube. Then a few chunks of steel angle or tubing welded between the tanks, so the entire weight isn't resting on the nipples and ball valve between the two tanks.

Nah, too thin. They are a bit too disposable, they'll rust through without much of an excuse. Plus, you'll have to weld up the rupture disc on the top, or it will rust through right there.


Reply to
Bruce L. Bergman

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