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What brass or bronze for water couplings?

enginesrus

Mechanical
Aug 30, 2003
1,012
What ID number for either material to use? May need to make a fitting for small water supply PE pipe.

I'm very familiar with 660 Bronze bearing material and know that would not be a good choice. Any advice is appreciated.
 
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It needs to be lead free. You may have a tough time sourcing bronze that is. This will likely steer you towards brass.
 
CuZn40 ( C28000) and CuZn39Pb2 (C37700) are common materials, cast by gravity casting(permanent mold casting) or precision casting.
 
I just plan of getting a Hex or round pin of said material about 1 foot long. So brass is the better choice?
 
Is the fitting in contact with regular drinking water or salt water?
If it’s drinking water, brass is usually the better choice since it has good antibacterial properties and is more cost-effective. I’d recommend C36000 (Free-Cutting Brass) for that.
But if it’s for saltwater or acidic environments, bronze would be best due to its superior corrosion resistance.
 
I recently re-piped my house. For all brass fittings I chose "lead-free" components that would be in contact with drinking water. The data sheets showed the brass alloy used by the various manufacturers was C69300.
 
C69300 is a wrought alloy, the cast version is C87850.
Watch out as some of the 'lead free' alloys have very high Zn and are susceptible to other corrosion issues.
There are alloys designed to resist de-zincification, and they usually have small additions of As, Bi, Se and such.
These are fine in water service.
The lead in alloys is really only an issue in hot water service, and you should not be consuming hot water anyway.
 

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