Plumbing – Earth clamp material for copper pipe

groundingplumbing

I have a copper water pipe i want to connect to earth. I bought some pipe earth clamps but I’m suspicious that maybe the material they’re made from is not suitable and will result in galvanic corrosion. The clamps are:
Strap: Stainless steel
Clamp body: Phosphour Bronze with zinc plating

Both the clamp body and strap will be in contact with the pipe. From what i can tell, copper doesn’t like to be in contact with stainless steel or zinc.
Is this correct? What material should the clamps be made from?

Best Answer

Are you considering passing a constant current through the clamp in a wet environment?

BTW, these have been the standard "go to" clamp for this purpose for more years than I know of, and I have not seen one where galvanic corrosion has made a hole in the copper pipe.

In the UK, all copper pipes have to be bonded including gas pipe supply as well. The clamps are as you describe, with an aluminum label about 2" by 1" with an embossed warning that it is for earth bonding - can't remember the actual text but probably easy to find : google...

Fit it, making sure the copper is clean, free from paint etc otherwise the paint is an insulator.