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What Coke Contains

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Re: What Coke Contains

#2
>>The top of the can is then added. This is carefully engineered: it is made from aluminum, but it has to be thicker and stronger to withstand the pressure of the carbon dioxide gas.Eh? The pressure is greater at the top of the can?

Re: What Coke Contains

#5

>>The top of the can is then added. This is carefully engineered: it is made from aluminum, but it has to be thicker and stronger to withstand the pressure of the carbon dioxide gas. Eh? The pressure is greater at the top of the can?

Good point, though I suspect it is down to the ring pull being the weakest part by design of being able to open it along the indented outline of the tab. Though it could also be so possibly from the aspect of the carbon dioxide want to rise to the top and that extra force would only incure more pressure towards the top (assuming the can is upright). There again thats a bit of a wild guess, but the only plausable explanation I can find as to why that would be so. Or it could be wrong in some way and mixed the ring pull tab area as the weakest link and worded it to impley the whole top.

Though I do know with most certainty that if placed in a freezer and left then it will expand at the top and the bottom and mostly rupture a bit around the ring pull tab in the process.

Re: What Coke Contains

#6

>>The top of the can is then added. This is carefully engineered: it is made from aluminum, but it has to be thicker and stronger to withstand the pressure of the carbon dioxide gas. Eh? The pressure is greater at the top of the can?

I would guess this has more to do with the need to stack the cans than pressure internal to the can because of carbon dioxide. But it is just a guess.

Re: What Coke Contains

#8

>>The top of the can is then added. This is carefully engineered: it is made from aluminum, but it has to be thicker and stronger to withstand the pressure of the carbon dioxide gas. Eh? The pressure is greater at the top of the can?

Pressure is the same on both ends, and the bottom of the can is already thicker than the sides of it. The top of the can is thicker than the sides, but thinner than the bottom, because you need to be able to open the can easily. So in order to make it thinner than the bottom but at least as strong, you use a different alloy.

Re: What Coke Contains

#9
Ok, bit of a bragging moment here: my grandpa, with two other gentlemen, created the process for machining seamless cans that is described here. Before them, cans had a lead seam in them. They discovered that you could draw down the aluminum and stretch it to form cans in one piece. He also invented the process for creating the bottom of soda cans, and his friend invented the modern tab on the top of soda cans.
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