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: re: bombed out pot bottoms and other bangers.

updated sat 15 jul 00


iandol on thu 13 jul 00

Dear Pierre Brayford=20

I agree that residual free water from inefficient drying is the cause of =
most solid clay explosions.

Regarding the cobble forms which do not have a pinprick hole for =
expanding air to escape. This is nature at work again. The air contained =
in an enclosed volume expands when it is heated. I believe, though =
someone may correct me, the equation is PV=3DRT and that the volume =
increases by a fraction of 1/273 for each incremental rise of 1 deg =
Kelvin. So the volume wishes to more than double. But in a contained =
space this cannot happen, so the pressure increases by the same factor. =
Now what was the modulus of rupture for dry clay?

I think it should be possible to calculate MOR if details were given =
about the size and thickness of the objects which explode.

Ivor. Inquisitive about this one.