API 571 Certification (Corrosion & Materials) Practice Test

Boiler water and steam condensate corrosion is most relevant for which material?

1. Stainless Steel

2. Alloy 600

3. Carbon Steel

4. Ductile Iron

The correct answer is: Carbon Steel

Boiler water and steam condensate corrosion are particularly relevant to carbon steel due to its susceptibility to corrosion in high-temperature and high-pressure environments found in boiler systems. Carbon steel can experience various types of corrosion, such as oxygen corrosion and pitting, especially when there are impurities in the water or when the pH of the boiler water is not properly managed. In boiler applications, carbon steel components can be prone to corrosion if not adequately protected or treated, as they can react with aggressive ions and form iron oxides, leading to material degradation over time. This is a common issue in systems where the chemistry of the water is not precisely controlled, making it critical to monitor and maintain water quality to minimize corrosion risk. The other materials mentioned might have different corrosion behavior or capabilities that help them withstand such conditions. For example, stainless steel tends to show better resistance due to the protective oxide layer that forms on its surface, while Alloy 600 has good corrosion resistance but can also be susceptible to stress corrosion cracking, especially in specific environments. Ductile iron generally exhibits good mechanical properties but does not perform as well as carbon steel in high-temperature steam environments. Hence, carbon steel is the material most relevant to corrosion concerns in boiler water and steam condensate applications