Concentration cell corrosion tuberculation

The three major forms of concentration cell corrosion are crevice corrosion, tuberculation, and underdeposit attack. Each form of corrosion is common in cooling systems. Many corrosion-related problems in the cooling water environment are caused by these three forms of wastage. The next three chapters—Chap. 2, Crevice Corrosion, Chap. 3, Tuberculation, and Chap. 4, Underdeposit Corrosion — will discuss cooling water system corrosion problems. 

Tuberculation Tuberculation concentration-cell corrosion may be found in all types of boilers, especially HW heating boilers and LP/HP steam-heating boilers. 

Localized, concentration-cell corrosion (differential aeration corrosion), occurring as Tuberculation corrosion Crevice corrosion Under-deposit corrosion Pitting corrosion All forms of localized, concentration-cell corrosion are indirect attack type corrosion mechanisms. They result in severe metal wastage and can also induce other corrosion mechanisms, e.g. Stress corrosion Corrosion fatigue... 

Sulfates are causative agents (along with oxygen, hydrogen, etc.) of the various types of concentration cell corrosion that result in pits, crevice attack, or tuberculation. 

Crevice corrosion, under-deposit corrosion, and tuberculation are all forms of concentration cell corrosion, and all involve oxygen to a greater or lesser extent. 

Concentration cell corrosion (crevice corrosion, under-deposit corrosion, tuberculation, pitting corrosion)... 

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