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Anodizing an immersion heater jacket

I have a .25" dia. PTC heater inside a 2.5" long, .315" diameter aluminum tube (wall .025") This small assembly is inside a .50" diameter stainless pipe. As hand lotion flows in this .50" pipe it passes by and around the heater assembly and is heated. The heating process is not continuous. Most of the time the device sits at room temp but the aluminum tube (heater) is always immersed in hand lotion. For short periods of time the heater will heat to no more than 300F as the lotion is demanded by dispenser. This is a consumer product and demand is limited perhaps 2 or 3 oz may dispense a day so the heat up condition is very limited. My question is: Will level II or III anodization be sufficient to prevent corrosion of the tube. Lotion is generally made up of water and mineral oil. Even a small amount of black oxide coming off the tube into the white lotion would be a disaster during the life use of this product - which is about 2~3 years.

Al Gebhard
New Sensations - Denver, CO 80209
2000

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From this distance, no problem foreseen. Aluminum produces white corrosion products, not black. But conjecture is no substitute for testing before submitting an item to production. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1999