Question

Explain 6 ways in which superheater tubes may be exposed to corrosion.

Answer 1

Superheater tubes may be exposed to corrosion through chemical corrosion, oxygen corrosion, galvanic corrosion, crevice corrosion, corrosion under insulation, and erosion-corrosion.

Step-by-step explanation:

Superheater tubes can be exposed to corrosion in several ways:

1. Chemical corrosion: Exposure to corrosive chemicals in the working fluid or environment, such as acids or alkalis, can corrode the tubes.
2. Oxygen corrosion: Presence of oxygen in the working fluid can cause corrosion on the inner surface of the tubes.
3. Galvanic corrosion: When dissimilar metals are in contact, such as in welding or joints, a galvanic cell can form and accelerate corrosion.
4. Crevice corrosion: Tight spaces or gaps in the tubes can trap moisture or chemicals, leading to localized corrosion.
5. Corrosion under insulation: If insulation around the tubes becomes wet or contains corrosive substances, it can cause corrosion on the outer surface of the tubes.
6. Erosion-corrosion: High fluid velocities or abrasive particles in the working fluid can cause both mechanical erosion and corrosion of the tubes.

These are some of the common ways in which superheater tubes may be exposed to corrosion.