Further comments from Roy Bash

Richard:



There is no definition in section 2 of the committee’s draft for “cathodic voltage” or “instant-off potential”.



Actually there is no such thing as a cathodic or anodic voltage because there is no such thing as a positive or negative voltage. When there is a voltage between two objects, one of them will be positive and the other one will be negative, but the voltage has no polarity. The polarity of the pipeline is designated with the P/S potential measurement because it is the anode (negative electrode) in the P/S potential measurement, but that does not mean it is a negative voltage.



In the natural corrosion process the anode is always the negative electrode of the corrosion cell (battery cell).

Magnesium is negative to steel and that is the reason it can be used as an anode to cathodically protect steel.



I realize that you already understood this, but the committee does not understand it. Please read the committee’s second definition of “cathodic polarization” in Section 2 of their draft. They obviously believe that forcing the pipeline (cathode) more negative renders it more active (anodic) rather than more passive (cathodic).



Oh well, I guess it could worse, maybe.



L.A. (Roy) Bash

Global Cathodic Protection, Inc.