Galvanised fittings and NaOH?

[julianf]

Im well aware of how damaging NaOH is to galvanising, but what im wondering is -

If i have some galvanised malleable iron fittings spare, and i want to use them for bio stuff, could i do something like soak them in NaOH for a while, and then use them?

Or is the galvanising likly to be so thick that the threads will not be usable afterwards?

Its just stuff like 1" pipework etc.  Basically, i want to buy some galvanised for our rayburn, but im sure to change my mind somewhere in the install, and have bits left over...


(ps i want to use galvanised on the rayburn, so as i dont have to bother painting the outside - im not concerned about the inside : )

[Soft top]

When you use galv pipe or fittings do not connect it direct to copper pipe. If you do there will be a electrolytic action which will cause corrosion then leaks.
 

[julianf]

Hmm...

Would i do better not using the galvanised then?  It was only so as i did not have to paint the outsides of the pipes anyhow.

[Soft top]

 
you can use galv and copper together as long as there is no direct metal to metal contact between them.
 i.e. use a plastic fitting inbetween them. Something like this...... http://www.philmac.co.uk/products/details/?type=2&sub=35

[julianf]

I was going to have iron from the rayburn to the thermal store, but the store itself has (or will have) a load of copper inside it.

If i need to electrically isolate various bits, it just seems like more hassle than its worth - i may as well just use black iron, and get out the hammerite again!


Thanks for your help.