Hi,

This might not be the right forum since it is more an engineering/galvanic corrosion question, but is it OK to thread a copper fitting (1" CxM) into a cast iron fitting? I'm worried about corrosion (copper threads = lots of surface area with cast iron threads & a galvanic cell is created).

Is it common to have cast iron fittings in a water system which is open to the atmosphere? I was under the impression that cast iron will rust and corrode if it is exposed to oxygenated water.

Any experts out there? Thanks in advance.

Hi Kronos..

Yeah, the joining of copper to cast iron in the presence of oxygenated water definitely leads to a galvanic corrosion.

Depending on the water, i.e. hard water or soft water, you can see hardly any reaction up to an actual deposition of minerals and other charged particles at the junction between the metals.

Is this application in question regarding a waste water or potable water system(s)?

Let us know more...

Mark