Which exchanger component is expected to have a higher corrosion rate?

The gasket surface of a carbon steel channel that has a brass tubesheet is expected to have a higher corrosion rate due to the corrosive environment it may experience. In heat exchangers, the interface where the gasket sits is particularly vulnerable to corrosion because it can be subject to leakage, moisture accumulation, and stagnant fluid conditions which promote corrosion processes.

Additionally, the presence of dissimilar metals, such as brass and carbon steel, can lead to galvanic corrosion, especially if the fluid in contact with these metals is conducive to such reactions. The brass tubesheet, in contact with a carbon steel component, creates a situation where the carbon steel may corrode more rapidly due to the electrochemical potential differences between the two metals.

The material properties also play a significant role. Carbon steel is generally more susceptible to corrosion than stainless steel, which has better corrosion resistance in many environments. Therefore, areas that are not adequately protected or where water or harmful chemicals are trapped, such as the gasket surface of the carbon steel channel, can lead to accelerated corrosion.

In summary, the combination of material properties, environmental conditions, and the presence of dissimilar metals at the gasket surface contributes to a higher expected corrosion rate in this scenario.