Re: How do you implode a 55 gallon drum?

How do you implode a 55 gallon drum?

I am an Earth Science teacher and have obtained 4 55-gallon drums to implode in front of my class. I put a little water in the bottom, put 4 hot plates under the barrel, capped it after it had steamed for about an hour, and quickly squirted cold water on the outside. It did not work.

It sounds like you got your water to a good boil before beginning, so that's not the problem. Other possible problems with your demo:

1. Did you remove the barrel from the heat? Hot plates (unlike gas burners as in the Indiana U demo) retain heat for a long time; think of them as electric-stove burners (and if you've ever cooked on an electric stove, you know that turning the burner off won't keep your food from burning). If you're still heating the bottom, cooling the sides won't do much.

2. The seal was inadequate. You need a really air-tight seal (the Indiana U people slathered their bung with vacuum grease) because you need a fairly large pressure differential for this to work. Large enough that a weak bung seal will fail before the barrel does. Also, some stock 55-gallon drums have bungs with small, deliberate leaks to prevent overpressures. (After all, 55-gallon drums are used to store volatile liquids, and a sealed drum might explode!)

   If you can find one large enough, I recommend using a good-quality, new rubber stopper to close the barrel. This should provide an adequate seal without vacuum grease.

3. A little bit of cold water squirted on the barrel probably won't remove enough heat for this to work. Try using a 5- or 10- or 20-gallon bucket of ice water. While the people at Indiana U used what looks like a good quantity of liquid nitrogen in combination with a water spritz, a sufficient quantity of ice-cold water should eliminate the need for more exotic coolants.

I am in the 55-gallon drum reconditioning business. Part of the process is drying the drum. We accomplish that by heating the drum in a horizontal position with a live natural gas flame the length of the drum for 20 seconds while the drum is rotating. If the bungs are tightened before the drum cools for about five minutes, then the drum will implode. Since this cost me money I train my employees by imploding a one-gallon empty plastic milk jug. For all new employees I put about 1/4 cup of tap water in the empty milk jug and microwave it for two minutes. Screw the cap on immediately. The milk jug will implode in about two minutes. If you must implode a good drum, then get a light gauge drum. Your local drum reconditioner will know the difference.

Best regards,
R. Mitchell
Mitchell Container Services, Inc.