Can one "warp" a pot/pan/skillet by transferring it
directly from the fire to running cool/warm water
on it? I know it makes grease fly everywhere, but
could it not also warp it?
The short answer: yes
Anytime one differentially quickly heats or cools any item, there are
thermal stresses introduced into the item because heating or cooling, unless
done slowly, tends to be uneven and has certain molecules moving more slowly
than the others nearby. The result of the thermal stresses can do
everything from shattering glass to warping or cracking of metal.
By the way, I have also seen in the past a huge fireball when someone
removed a pot which had a grease residue only, from a flame, and placed the
pot into a tub full of water. Needless to say, this can be very
dangerous.....the better choice is to remove the source of heat, or remove
the pan to an "off" burner and let it cool slowly.
Thanks for using NEWTON!
Generally, the thicker the pan, the more resistant it is to warping. I know
from experience, however, that you certainly can warp a metal sheet
(griddle, cookie sheet, saucepan) by the method you describe.
Richard E. Barrans Jr., Ph.D.
It depends on the degree of warping you expect. Indeed, if you pour cold
water over one side of a hot flat pan, there will be a temperature
difference through the thickness of the pan. This temperature difference
will warp the pan but the warping is rather small and cannot be seen by
naked eyes. You can see this, however, if you use instruments that can
measure slight movements of the pan.
Splashing of oil is an unrelated phenomenon. Grease splashes because the
water poured into a hot (over 100 C =212F) oily pan boils and evaporates
violently. It takes some of the grease with it. This is the splash, which
we particularly notice when cleaning the stove.
Dr. Ali Khounsary
Advanced Photon Source
Argonne National Laboratory
Argonne, IL 60439
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Update: June 2012