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Anodize for ice maker evaporator

1998

We are trying to identify a type of anodize that would be suitable for use on an aluminum ice maker evaporator (the part of an ice machine that freezes the ice). A big concern is the corrosion resistance of the material. Typically these evaporators are made using copper plated with tin or electroless nickel. They are subject to extreme thermal cycling (-10F to 80F every 20 minutes), ice machine cleaners (typically a diluted solution of phosphoric acid), a wide variety of tap water quality (pH range from 4 to 11, hard or softenedÖ), and of course the freeze-thaw and possible abrasion caused by the ice. Corrosion resistance equal to that of tin or electroless nickel would be adequate.

The part itself is not submerged in water, but will have either water flowing over it, ice frozen to it, ice being melted from it, or it will be sitting there, in air, while not in use. This evaporator will be fabricated using a roll-bond process on 1100 series aluminum. The part will be roughly 12" x 18" x 0.060" thick. Annual quantity in the 5K to 50K units per year range.

I would appreciate advice on this project!

Thanks for your help!

John Broadbent
equipment - Denver, Colorado

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1998

John:

Of all the aluminum finishes I believe that Hard coat will hold up the best in your environment. We are a metal finishing house that specializes in Hard coat anodizing, we would be willing to run samples for you to test.

Thanks
Regards,
Bob

Bob Bramson
B&M Finishers / Prismatic Stainless Steel

Kenilworth, New Jersey

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The company I work for has experimented with the processes for such a machine. It would be more beneficial to stay with electroless nickel plating if you prefer the part to withstand the corrosion. Run samples and have them expose them to water and temperature over an extended time. Then compare your findings. Electroless is likely the answer. Good luck!

Mike [surname deleted for privacy by Editor]
1999

I am looking for machines and technology to produce evaporators and condensers destined to work in commercial refrigerators. I would appreciate any advice on this problem. Thanks for help.

Peter Labanowicz
- Poland
2000