Alloy 706 vs. Demin. Water

[EffHeat]

Can anyone help me with the performance or longevity of Alloy 706 (90Cu/10Ni) tubing running no more than 190deg. demineralized water?

 

[GarySCWSVI]

The demin water will be very agressive on that alloy. It will likely be degraded by the Cu and the Ni be taken into the water. The alloy will be corroded by the water.

Gary Schreiber, CWS VI
The Purolite Co.

 

[bimr]

There are some great articles on the NIDI website

http://www.nidi.org

that cover this matter.

 

[EffHeat]

bimr, I could not find anything on that site for demineralized water. Only desalizied and distilled. Thank you.

 

[bimr]

Distilled water is essentially the same thing as demineralized water.

Here is another source for you:

http://www.chicagotube.com/stockbook/boiler/selection_guide.html

Don't understand GarySCWSVI's comments. Perhaps he can elaborate.

 

[bimr]

You can also contact Olin Fineweld Tube:

For more information about Olin Fineweld Tube, contact fwt@olinbrass.com or call (573) 885-6546.

 

[cub3bead]

There is one key difference between distilled and demineralized water and that is the dissolved oxygen content. However, once the distilled water is stored in a tank open to the atmosphere that difference goes away. But the DO content makes a very big difference in the corrosivity of the water.