wu :: forums (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi)
riddles >> microsoft >> Beer cans
(Message started by: jojo on Nov 1st, 2003, 2:06am)

Title: Beer cans
Post by jojo on Nov 1st, 2003, 2:06am
Why are beer cans tapered on the ends?

Title: Re: Beer cans
Post by Sir Col on Nov 1st, 2003, 4:29am
I guess that part of the reason is, [hide]so that they will stack[/hide]?

Title: Re: Beer cans
Post by towr on Nov 1st, 2003, 10:01am
Added strength perhaps..
Maybe esthetics.
It makes the can look bigger for the same volume..

Title: Re: Beer cans
Post by maryl on Nov 8th, 2003, 2:58pm
Could be it has something to do with the machinery they use to make them.

Title: Re: Beer cans
Post by James Fingas on Nov 17th, 2003, 1:34pm
Sir Col:

Quote:
so that they will stack?

Yes, but soup cans stack too, and they're only tapered at the bottom.

towr:

Quote:
Added strength perhaps..
Maybe esthetics.

Don't see why it would add strength, and aesthetics (although possibly true) is not a satisfying answer...

Maryl:

Quote:
Could be it has something to do with the machinery they use to make them.

The machinery is designed to make them tapered at both ends. But I'll bet you it's harder to make pop cans tapered than it would be otherwise.

It could be due to materials cost: the aluminum for the top of a can is significantly more expensive than the plate steel for the sides. Of course you need some aluminum to put the spout and tab on.

Title: Re: Beer cans
Post by visitor on Nov 17th, 2003, 2:24pm
Having worked at one time in a Pepsi bottling plant, I'm pretty sure the reason is strength (although I don't know the physics of it). The difference between pop and vegetables (which are canned in straight sided cans) is the pressure inside. Hopefully it won't be too great at the moment you pop the top, but shake the cans up inside a hot semi for a few hours and the pressure gets pretty high. That's also why they have concave bottoms, and how it happens that you sometimes get a can with the bottom bulging out; think of the pressure it takes to do that.
Pop is canned cold (to avoid a lot of foaming and carbonation loss. But then it must be warmed or moisture will condense on the cans and ruin the cardboard cartons. When the production line sometimes gets shut down for a while and cans stay in the warmer too long, they start exploding at any little jostle when the line starts up. I've seen cans explode in a guy's hand as he was taking hot cans off the line. (no injuries fortunately, but you do get soaked).
I assume sharp, square corners could not handle the pressure as well.

Title: Re: Beer cans
Post by towr on Nov 17th, 2003, 2:33pm

on 11/17/03 at 13:34:37, James Fingas wrote:
towr:
Don't see why it would add strength,
The rounder a body the better it withstands inside (or outside) pressure..
A sphere, however, isn't practical. To stack them, and place them on a table without having them role off, they need to be relatively flat at top and bottom. So tapering the ends of the cylinder-like can gives the best overall result..

Title: Re: Beer cans
Post by hemorraged on Sep 10th, 2004, 10:12am
i don't drink beer, but the reason the cans are tapered at both ends is
so that they can make the cans look bigger but put less drink in them.

we live in a capatalist world, eh?

Title: Re: Beer cans
Post by John_Gaughan on Sep 10th, 2004, 1:33pm

on 09/10/04 at 10:12:46, hemorraged wrote:
i don't drink beer, but the reason the cans are tapered at both ends is
so that they can make the cans look bigger but put less drink in them.

That explains why they are sold by liquid volume, not can size ;-)

As was explained previously, the reason is that tapered cans resist the pressure inside (and out) better. Different shapes deal with pressure differently. Rounded structures, such as spheres and tapered cans, hold liquid pressure better. Triangles are great for resisting shearing in buildings and construction equipment.

This is also why submarines are shaped somewhat like bullets. That round shape resists water pressure very well.

Title: Re: Beer cans
Post by cherry12345 on Dec 3rd, 2007, 4:45pm
because having them tapered allows company to save cost from raw material (aluminum..whatever they are using).  

Title: Re: Beer cans
Post by webtasarim on Oct 6th, 2013, 4:42pm
eay to drink ?

Title: Re: Beer cans
Post by mejohnreeves on Oct 25th, 2013, 7:17am
I think it increase the strength of can. I suggest (irrelevant link removed) in the concern of this thread.



Powered by YaBB 1 Gold - SP 1.4!
Forum software copyright © 2000-2004 Yet another Bulletin Board