Engineering Expert On Plumbing Corrosion Part 2

Engineering expert Frank Baumann, PE, is a registered corrosion engineer, certified water treatment operator and certified water quality analyst. Here he writes on the internal corrosion of plumbing.

Some of the initiating factors include manufacturing defects such as internal surface imperfections, poor workmanship in the installation of the pipe (flux runs, excessive heating, stagnation-formed films in copper pipe, overthreading in steel pipe, faulty joints, direct contact of dissimilar metals [galvanic corrosion], etc.) and wrong (too small) pipe sizes, resulting in excess water velocity thus causing erosion corrosion.

So does the water play any role in this? Of course it does. For corrosion to occur, the corrosion curent must flow from the anode to the cathode. This requires a conductive medium – the water. All waters (with the exception of pure distilled water) are capable of carrying the corrosion current. And some waters are indeed more aggressive than others. Frequently, the water is implicated only inasmuch as it sustains the corrosion reaction – but the water is not the primary cause for the corrosion to occur.