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Feeding Current to Anodize Tanks

September 12, 2009

We are installing a 27' Type-2 anodize tank. Our hard anodize tank and Chromic tank have anodes at each end. It is fed from the same source. Is this called strapping when you feed bus-bar at both ends?
On an 8' tank or 11'tank I have had the feed coming in on one end of the bus-bar and it works fine at that length. On a 27' tank you might lose some needed power plus it might not be an even flow.
I think feeding at both ends is the best.

Would appreciate some input.....Thanks John

John Merritt
Manager - Gardena, California, U.S.A.

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I've never used or heard the term "strapping" in that context, but I suppose it could be used locally.It can't hurt (electrically speaking) to bus from both ends. But as long as the anode and cathode bars are big enough (1 square inch of copper per thousand amps), and as long as the contact blocks are reliable, it's not necessary.

Sometimes it's a matter of what is bought from whom. If you buy an anodizing line with anode and cathode bars but less installation from an OEM, they are likely to keep their costs low by sizing anode and cathode rods small, such that the tank requires bussing from both ends. If you buy it with installation included, they are liable to generously size the anode and cathode bars so they only have to bus it from one end.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 21, 2009