What does oxygen in a boiler drum typically cause?

Oxygen in a boiler drum is known to cause pitting, which is a localized form of corrosion that leads to the formation of small holes or pits in the metal surface. When dissolved oxygen enters the boiler system, it reacts with the iron in the steel and forms iron oxide, which can lead to these small pits. Pitting is particularly dangerous because it can penetrate the material more significantly than general corrosion, often going unnoticed until significant damage has occurred.

The presence of oxygen is problematic because it accelerates the corrosion process, especially in the high-temperature and high-pressure environments typical within a boiler drum. Maintaining good water treatment practices to remove dissolved oxygen is crucial for extending the life of boiler components and ensuring safe and efficient operation.

While corrosion is a broader term that encompasses various forms of degradation caused by oxygen and other factors, pitting specifically refers to the localized effects that oxygen can create, making it the correct focus for this question. Other forms like scaling and overheating are related to different chemical or thermal processes and are not primarily caused by the presence of oxygen in the water.