|Index & Notes|
Aldermanic Slide Showing YDI and "Putting the Fire Out"
Cathodic protection is so ingrained at the City of Calgary I couldn't even find a written justification for our forty-year-old rule of installing an anode at every repair site. But on the right you can see what happens: anodes can "put the fire out", as the crews said, on a whole main. This main has actually gone 35 years now with no breaks, after five anodes installed in the late 70s. On the left, a picture of YDI, yellow-jacketed Ductile Iron, an oil industry product we adapted to water from 1973 to 1980 when we went PVC. More important than the heavy coating is that it's installed with anodes, you can see a bonding strap in the picture. YDI has one-tenth the break rate of bare DI, but the breaks shoot right up on it when the anodes wear out, until they're replaced. I'll be showing you a dramatic example.
My presentation will be in two parts: first, the cost/benefit oriented, probability-based "True Asset Management" approach I reached in 2012 after 20 years of data-collection and experiment. Then, the rule-of-thumb inference approach I had to use up to that point, except when I had the real story from an inspection.
© Roy Brander, P.Eng 2016