Page 355 - Challenges in Corrosion Costs Causes Consequences and Control(2015)
P. 355

CORROSION DAMAGE, DEFECTS, AND FAILURES                         333
























            Figure 5.4 Tape-wrapped air valve. (David Raymond, City of Ottawa, Public Works &
            Services.)


              The use of wax taping and magnesium anode resulted in very little corrosion,
            requiring the normal maintenance and inspection of the chamber for valve integrity.
              Corrosion of bolts in areas other than valves was observed as shown in Figures 5.5
            and 5.6. The economies of cathodic protection compared with the replacement of the
            water main are illustrated in Table 5.6.



























            Figure 5.5 Four-inch T-bolt from 8-in valve. (David Raymond, City of Ottawa, Public Works
            & Services.)
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