# Corrosion difference



## 422 plumber (Jul 31, 2008)

Look at these two pics. These nipples are probably 15 years old. The end that is gunked up was screwed into a brass ball valve, the better ends were screwed into galvanized 90.


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## 422 plumber (Jul 31, 2008)

The job was in Chicago, which gets Lake Michigan water, which is naturally soft. These were feeding a drinking fountain, set between two ovens/production lines that bake paint onto cans. The oven are set about 290 degrees. There was a thermometer by the fountain, it was 114 degrees. I was doing some serious sweating.


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## Protech (Sep 22, 2008)

Standard galvanic electrolysis


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## 422 plumber (Jul 31, 2008)

Yes,
I was posting this to show anyone who says that a brass nipple is a good dielectric jumper. My personal opinion is that stainless should be used between galvanized and brass. However, this was probably 15 years old, so it probably wouldn't have started leaking in about 50 more years.


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