"Phil L" wrote in message
. ..
Kay wrote:
:::::
::: Hmmm...now I think I see where everyone's going wrong!...the
pipe
::: and tap will both be (all but) drained, having turned off it's
::: water supply and left the tap open...what little there is in
::: there *cannot* expand sufficiently to burst a pipe.
:::
:: But wasn't it you who said
:::
::: The pipe contains 15 mm of water, encased in a 1 mm copper
:::::: sheath, the tap contains 25mm of water encased in a 10mm
brass
:::::: sheath, which is going to freeze first?
::
:: ?

Yes I did say that and in the case of the pipe being horizontal,
there is a
possibility, even with the water turned off, that the pipe and tap
could
still contain water, (not under any pressure) and with the tap fully
open,
it still cannot burst a copper pipe if it froze - it takes the
easiest
route.

Anyway - I have (accidentally) frozen cans of lager in the deep
freeze many
times and they haven't bursted the can

Have you ever thought of the fact that there is probably a small space
ibn the can, containing gas into which the lager might expand?
Have you ever thought of the consequences of the fact that the
solubility of gases in water incfesaes as the temperature decreases?
Have you considered that the shape of the bottom of a lager can is
such as to allow it to be deformed under pressure in such a way as to
increase the internal volume?

- the beer is already under pressure,

Which, of course, decreases as the temperature drops.

the material is about a tenth of the thickness of copper pipe and
they have
been in there for days without bursting, I think people
underestimate the
strength of water pipes

No. water pipes are known to burst on occasion.

....if the tap is open, the water/slush/ice will
escape through there before getting through the metalwork.

So according to you all those burst water pipes are just in people's
imaginations?

Franz