The message
from "Franz Heymann" contains these words:

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.

However, on freezing, i think that all the dissolved gas is freed -
certainly, I have had cans explode in the freezer - not just split.

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?

To be fair, most of those instances would be when the taps are left
closed. It's a sensible precaution to take, but not infallible. It just
depends on where the ice forms a solid and unmovable plug.

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
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