I'm sure the lady concerned didn't find this incident amusing, but it made me laugh.
The woman, in her 70s, had popped the oven on before leaving with the intention of preheating it so she could get straight to cooking when she returned.
What she didn’t realize however was that she had also turned on the stovetop, upon which she had left a mostly full can of antibacterial Glen20 spray.
While she was out, the highly flammable can got so heated that it blasted up with such force that it not only went through the ceiling, but straight out the roof.
“It shot straight up like a rocket,” said Jake Whalan, director of DYAD Constructions, which was called in to address the aftermath.
There's more at the link, including photographs.
I wasn't surprised to read that the can exploded. What did surprise me was its vertical launch at high velocity, leaving a neat round hole in the ceiling and then bursting out through the roof. Nobody knows where it ended up. I'd have expected the can to explode in every direction, breaking the pressure vessel inside it, but it seems it was better or more strongly designed than that. (It made a heck of a mess of the stovetop, too!)
I'm glad nobody was at home when it went off. That must have been a very loud noise indeed...
Peter
12 comments:
If she had a steel roof, it would have made for an interesting ricochet.
Generally the ends of a cylindrical pressure vessel are the weak points.
The bottom of a can is often its weakest part, especially with the metal weakened with heat.
Beer bottles usually fail at either the bottom or the neck. A crown cap is actually stronger than the bottle...
Steel pressurized spray cans have one of two designs. Either a seamless body with a roll crimped on top and bottom, or a rolled body with a crimped seam and a roll crimped top and bottom. The bottom is concave to better resist the force of the pressure inside the can.
Once heated, occasionally the side will split, but usually the bottom seam is the failure point due to geometry and stress. The top, being much smaller, doesn't fail. So you end up with the equivalent of a small steam boiler explosion. All that high pressure liquid flashes into vapor and, yes, the thrust is directed like a rocket. Also, like SpaceX saw back in April, the surface under the rocket is subjected to all the fury of the launch. I am glad to hear no one was harmed.
Thanks to my mom, I had a can of oven cleaner do that under the counter due to rust on the bottom rim. No heat needed. Popped a nice cracked hole pattern in the countertop and caused us to have to evac due to the nasty smell for a day. Love my mom.... love my mom.
Then there are those vertical garage door springs. Had one of those go blasting into the neighbor's yard through my roof. At 1 in the morning.
Pressure and tension are nothing to laugh at.
Add heat into a pressurized vessel and you, too, can create your own smallsat launcher...
Someone should tell Elon Musk about the new, fortuitously-discovered rocket engine
Some years back the wife decided to make caramels and put a can of condensed milk in a pot on the range to heat up by boiling it. She then decided to take a brief nap which lasted somewhat longer than she planned. Sometime later I wandered into the kitchen and noted that the pot had boiled dry. Without thinking it out I then tried moving the pot from the burner at which time the can exploded coated everything in the room with its contents, myself included. Luckily I was missed by any shrapnel though the noise certainly aroused the entire household. I jokingly accused my wife of using IED in an attempt to assassinate me, which she denied. The incident still comes up periodically usually by one of the kids.
Find the "Mythbusters" episodes dealing with water heater explosions. It is impressive what pressure can do.
Wow... THAT is an odd one, to put it mildly.
Back when I was a office machine service tech in south GA, I had a can of spray solvent go off where it blasted through the Maxima station wagon's roof leaving a 2.5 inch hole. I managed to get the car pulled over before I succumbed to the gas but managed to open the door to fall out of the car. Temps were in the upper 90's that day.
A lot of pressurized cans have a small rubber button in the bottom head of the can. If the contents heat up and expand the rubber plug pops out and releases the pressure before it explodes.
In thst case it would have acted like a rocket nozzle. It likely heated up enough to increase the pressure. Pressurized contents escaping will expand as it drops to atmospheric pressure.
Exile1981
Back from basic training and tech school I showed my dad how we heated Kiwi shoe polish to liquify it. He obviously liked the idea because he later put a can on top of the stove burner, an electric that of course has questionable heat control, and exploded the can. Shoe polish EVERYWERE. Amazing how much there is in that can when liquified and thinned in flight. Mother was not pleased, but I thought it was funny as hell. A smoker, he later died of lung cancer. Miss him.
SpaceX had their SN1 prototype fail during a cryotest and it sent 80 or so tons of ship flying, then as it landed the top tank ruptured and sent about half of the ship flying several hundred feet.
bad things can happen when pressure tanks rupture, that's why high pressure tanks are supposed to be chained in place when they are being used, to make it less likely that they will go elsewhere unexpectedly.
David Lang
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