Copper and Aluminum Fittings 1

[EECougar]

Does anyone know of an article that explains exactly why aluminum and copper fittings should not be connected together and why bronze should be used to connect aluminum to copper?

 

[dpc]

From copper trade assoc, so probably a little biased, but provides some background info:

http://www.copper.org/publications/pub_list/pdf/a6107.pdf

"The more the universe seems comprehensible, the more it also seems pointless." -- Steven Weinberg

 

[waross]

Copper salts will cause corrosion of aluminum. Aluminum has little effect on copper.
When copper drops are used to connect transformer secondaries to overhead aluminum conductors the copper must always be below the aluminum. If the copper is laid on top of the aluminum conductor the life expectancy of the joint is greatly reduced.
The rain water reacts with the copper to form small amounts of copper salts. If the copper is below the aluminum, the rain carries the salts away from the aluminum.
These connections are typically uninsulated.
If a copper/aluminum connection is insulated and moisture finds its way inside the insulation, the joint can be expected to fail.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Laplacian]

I've seen bronze connections react with aluminum pads in the vicinity of cooling towers. I used these transition pads to make the connection and have not had any issues over the last several years.

http://www.hubbellpowersystems.com/powertest/catalog_sections/Ecat/SF-11.pdf