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Aluminum in the Plumbing Industry

I manufacture a product which currently has its manifold built out of a solid block of Delrin. Delrin is calcium proof and have never had problems with calcium or lime build up in our manifolds.

The price of Delrin is skyrocketing... I am considering building the manifolds out of Aluminum. My concern is that aluminum will break down over time from household water which contains calcium and lime.

My question is this...

Will aluminum survive 10 years of constant contact with household water and the intermittent pumping of water within an Aluminum manifold?

If not, is there a coating with would allow more then sufficient protection in the above mentioned environment?

Richard W Nielsen
- Oceanside, California, USA
2005

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2005

Hi Richard,

Not knowing the size etc.etc of your Delrin manifold, the first thing that comes to mind is why isn't he, ie. you, using common household plastics.

PVC has temperature limitations
ABS is somewhat better on heat and very strong
CPVC costs quite a bit but is better than PVC temperature-wise.

But why Delrin? Why not Terylene (Polyethylene terphalate)?

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

If thick enough, aluminum will survive. Many years ago, aluminum pipes were the most popular way to feed toilet tanks in Mexico (we now use reinforced plastic hoses). Aluminum used to fail because it suffered during valve instalation or repair, not due to chemical attack. They were at least 1mm thick as I recall. Also, I still have an old cofee maker with some aluminum parts in it. I don't know if this will make me forget about things but it still brews fine. In both cases build up of lime and calcium is expected.

Guillermo Marrufo
Monterrey, NL, Mexico
2005