Cutting aluminum tanks safely??

[Fighterpilot]

Getting ready to start cutting. Have a counterrotating saw with two blades, saws-all, and a grinder with cutting blade. It is my understanding one can cut a diesel tank safely. OR, should I have air blowing down the filler vent and remove as many fittings as I can to get the air to flow thru the tank as an additonal safety precaution. Does diesel fumes, in the right concentration have a flash point? Suggestions solicited, please.

 

[Codger2]

Fighterpilot wrote:*Does diesel fumes, in the right concentration have a flash point? Suggestions solicited, please.

* * * ** Several years ago, while fishing at a wilderness fish camp in SE Alaska, a lodge employee was killed when he took a torch to an old rusted diesel tank. When it blew up, he was thrown over a hundred feet & later died in an air ambulance on the way to Seattle.

Now, I know you're not using a torch but please ventilate those old tanks well before causing some sparks from a saws-all.

-- Edited by SeaHorse II on Friday 3rd of February 2012 03:32:25 PM

 

[Larry M]

Use dry ice,*it's the fire triangle; Oxygen+Heat+Fuel=Fire.* By using dry ice (carbon dioxide) you are removing the oxygen so no fire.* Ventilation alone*may may not work.* If there is any sludge in the tank, you can still have*an explosive atmosphere.* I don't remember what the lbs of dry ice/gallons of tank volume are but contact*the fire department or a company that services underground storage tanks.* The use of dry is*an industry accepted method.

 

[chc]

I would be concerned a bit about the baffling in the tank; I believe that Californian tanks have some baffles in them, but I'm not positive about that . Would it be possible to pour in some dishwasher soap; couple of cups or so, then hose things down & get lots of suds. (I'm also assuming that all the fuel has been drained out). Then I think I might cut a hole in the end of the tank w/the suds & let it vent a bit; then press on from there. What the hell.. you already know how to fly if it goes wrong. Kidding... good luck & be careful.

 

[Codger2]

superdiver wrote:*that guy was a patient of mine....* Except i thought it was a gas tank, not diesel???

* * * * My wife & I arrived back at the lodge about an hour after it happened.

******* The lodge owner had gone to Juneau with the injured employee to catch an air ambulance to Seattle. We were told by the lodge management team that the tank was an old diesel tank.

They had so many OB boats that it is entirely possible that it was a "gas" tank.

I believe the poor fellow was from South Carolina & the lodge owner flew back there, with the body, to address the family.

It sure put a real "funk" on the rest of our stay.

 

[Edelweiss]

Yes, using a cutting torch on anything that contained hydrocarbon fuels is deadly if done wrong.* Makes me nervous when I go to a shop and see them welding on a used tank or cutting an old*55 gallon*drum, even though they're using proper precautions.* I would go with the inert gas, dry ice, just to be on the safe side.*

I had an old diesel furnace tank removed from one of my rental properties recently.* After draining it of oil and sludge the contractor put a hydraulic tool in a hole in the tank and peeled it open.**Once it was opened up they cleaned the residue and crushed the tank flat.* They said*they used a saws-all for years, but they were running into tanks which had contained unknown chemicals, so they*switched to the "shears".**It peeled the metal like butter and was quicker than a saw would have been anyway.


-- Edited by Edelweiss on Friday 3rd of February 2012 08:13:13 PM

 

[Fighterpilot]

Tank will be empty. Drain on the lower corner. Now has about 30 gal. but pump out and than drain should get it empty. Will put in a cup of Dawn and hose with high pressure to cause suds as suggested here and on boatdiesel.com. Dry Ice sounds like a good idea so will drop some of that down the filler pipe. Pretty sure the tank has baffles due to its size, but assume there are openings at the corners of the tank so water can move about and hopefully take some suds with it. Can also get some dawn in the high end as there is 1/2 inch plug there. This along with dawn in the low end filler should cover the bottom. Thanks for the advice.

 

[Restitution]

I have two new 100 galon tanks onboard that are in use. I also have two "old" tanks that are not being used. These older tanks need to be cut open and cleaned. (Rusty and gunky). I had planed on taking tanks out, filling with water and using an pnumatic cutting wheel. I hadn't heard of soap nor dry ice. What does the soap do?

 

[Fighterpilot]

As I understand it the soap should be foamed up which will help control any residule diesel fuel or diesel coating in the bottom of the tank.