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Heating calculation of dry off oven after water spray

What is the formulas for knowing the heat temp and time for drying my aluminum profiles after they came out from water spray stage

Yoni Malki
Student - Ashdod, Israel
November 25, 2009

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I know of no simple formulas that will tell you the right time/temp combination. While you can use some heat and mass transfer equations to estimate how fast a film will dry under a given set of circumstances, the big question is going to be how the part drains and if there are any areas where pooling might occur. A lot of this depends on part geometry, how it's hung, the presence of drain holes, etc. The use of such things as air knives to blow off excess water can drastically affect drying time. Airflow configuration/flowrate can also have a significant impact.

A simple thing to try would be to bake a test part in a small oven of some type and see how long it takes to "dry" to an acceptable level. That should give you an upper boundary since a forced air convection oven would have higher heat and mass transfer rates.

Christian Restifo
- Pittsburgh, Pennsylvania
December 1, 2009