Oxy-acetylene safety demonstration - GIF

[ToolTalkBot]

Oxy-acetylene safety demonstration.




Previously:

Acetylene-filled balloons explode - GIF
Cutting thick concrete slab with oxyacetylene torch - GIF
Oxy-acetylene gas bottle crash explosion - video
Oxyacetylene pipe beveler - GIF

[Frank S]

Somehow, I fail to see this as a safety demonstration. At best it was a demonstration of how a mixture of volatile gas and oxygen will explode when ignited. There is no explanation of the type or mix ratio of which gas was used. Obviously OXY/ACT, can be explosive. but the same can be said for just about any combustible gas when mixed with oxygen.

[BuffaloJohn]

Somehow, I fail to see this as a safety demonstration. At best it was a demonstration of how a mixture of volatile gas and oxygen will explode when ignited. There is no explanation of the type or mix ratio of which gas was used. Obviously OXY/ACT, can be explosive. but the same can be said for just about any combustible gas when mixed with oxygen.

Agreed - explainations really are needed because without them, it is just playing.

I saw an experiment MIT did for the USAF which measured the velocities of various gases used in a potato cannon (yeah, this is the stuff DOGE should be looking at) and this is what was concluded:

"To measure the potato’s acceleration, they filmed proceedings with a high-speed camera at 2000 frames per second. They then plotted the position of the potato in the barrel against time and calculated the exit velocity when it left the muzzle. They repeated the experiment five times for each propellant.

The results point to a clear winner. Propane, ethanol, methanol and butane all produce muzzle velocities of between 28 and 48 metres per second. But acetylene is in a class of its own, producing a muzzle velocity of 138 metres per second. That’s over 300 mph."

[bruce.desertrat]

Somehow, I fail to see this as a safety demonstration. At best it was a demonstration of how a mixture of volatile gas and oxygen will explode when ignited. There is no explanation of the type or mix ratio of which gas was used. Obviously OXY/ACT, can be explosive. but the same can be said for just about any combustible gas when mixed with oxygen.

My welding shop teacher in High School did a demonstration like this, only smaller scale (baloons) First he filled on up with Oxy, it wnt 'pop' , then just acetylene, it went 'foomp' quietly with little black threads everywhere, then with a mix . "Listen close, so you can tell the difference" he said. 'BAAANG' and we all jumped back involuntarily. May not have been scientific, but it did impress upon a buncha 15-year-olds not to **** around with that.

[bruce.desertrat]

Agreed - explainations really are needed because without them, it is just playing.

I saw an experiment MIT did for the USAF which measured the velocities of various gases used in a potato cannon (yeah, this is the stuff DOGE should be looking at) and this is what was concluded:
[/B]

This reminds me of William Proxmire who used to make his 'Golden Fleece Awards' by cherry picking something and then proclaiming it 'wasteful spending'

I doubt very much that the actual AF proposal was 'determine the best fuel mixture to propel a potato' . Rather it was a proposal to determine optimal gas mixtures for a gas-fired cannon or other something else powered by igniting gas mixtures, and MIT had a high-speed video camera, and potato gun lying around to use for the study. It's a known system that was easy to to perform accurate experiments with.

It's like infamous 'shrimp treadmill' being flagged as wasteful government spending, when the treadmill portion of the money was about $1000 (after the prototype to prove it worked was built from scrap) out of a much larger grant for studying commercially valuable seafood species. (the treadmill portion was designed to quantitatively measure shrimp reaction to varying water quality )

[Floradawg]

Whether or not the shrimp study was a silly waste of government funds, there are countless examples of really stupid ways of wasted funds. It's really just another example of the idea that if you're spending someone else's money, it doesn't really matter how much you spend or whether it's money well spent.

[BuffaloJohn]

I doubt very much that the actual AF proposal was 'determine the best fuel mixture to propel a potato' . Rather it was a proposal to determine optimal gas mixtures for a gas-fired cannon or other something else powered by igniting gas mixtures, and MIT had a high-speed video camera, and potato gun lying around to use for the study. It's a known system that was easy to to perform accurate experiments with.

Here is one citation:
[1305.0966] Studying the Internal Ballistics of a Combustion Driven Potato Cannon using High-speed Video

It's published here in the European Journal of Physics
https://iopscience.iop.org/article/1...-0807/34/4/915

Here is the MIT article:
https://www.technologyreview.com/201...le-velocities/

There is NO information regarding any alternate motive.

The only takeaway that I had in mind when mentioning the article was the relative velocity of acetylene versus some other gases when ignited - which is useful when explaining the danger of some gases.