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Name: Frank
Status: other
Age: 50s
Location: N/A
Country: N/A
Date: 1999-2001

I have noticed that a frozen water pipe is often not split open due to freezing. However when you apply a certain level of heat, to thaw the pipe, and it does not have to be excessive heat, the pipe will often split before the thawing process is complete.

If you apply very low level of heat, over a long period of time, the pipe will often survive the thawing.

Is this because ice , being in a "Solid State", now acts like most other materials and expands, just before the actual conversion back to its liquid state, or is there some other reason?


If the frozen pipe was already stressed near the breaking point, perhaps the localized heat vaporized some of the meltwater and caused the pipe to finally yield to the pent up stress.



While water contracts when ice is melted, i.e. water at 0 C. is less dense than ice that reduction in volume only exists up to about 4 C. after which water expands upon further heating. So if you melt a section of frozen pipe capped by two plugs of ice and the water temperature exceeds 4 C. and the ice plugs are immovable something has to give, and what gives is the pipe.

Vince Calder

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