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What are the most common failure modes observed in air cooled fin fan heat exchangers in hydrocarbon service?

Tube leaks and ruptures as we see the most of the times in finfan coolers.
Those leaks mainly originates from internal corrosion, under-deposit corrosion, erosion-corrosion at high velocity areas, flow-induced vibration, thermal fatigue, dead-leg condensation attack, sulfidation in hydrocarbon service.

arcpro,
What are the conditions which could lead to internal corrosion, and are there are repair methodology once tube leaks /ruptures are identified?

Another cause which can fail the fin fan heat exchangers is the Corrosion Under Fin.
A very common but underestimated problem. Moisture, salts, hydrocarbons, and atmospheric contaminants get trapped between aluminum fins, steel tube surfaces.
This creates hidden corrosion cells, especially severe in coastal plants, humid climates, marine atmospheres, sulfur-rich environments. It is dangerous as the fins hide the wall loss until leakage occurs.

Internal corrosion in air cooled fin fan heat exchanger tubes usually develops when the process fluid becomes chemically aggressive, contaminated, stagnant, or operates in conditions favoring corrosion mechanisms. In hydrocarbon service, the problem is often a combination of water presence + corrosive species + temperature + flow effects.
Tube plugging is the most common method to get over with the ruptured tubes.
Sleeving is another, recommended when you are loosing a lot many tubes.
Tubes with greater damages are considered for replacement.

sys1 wrote: 22 May 2026, 13:38 arcpro,
What are the conditions which could lead to internal corrosion, and are there are repair methodology once tube leaks /ruptures are identified?

Do you have any reference of performing sleeving for finfan tubes upon corrosion?
I understand if damage is uniform and spread at a larger area, sleeving may not be appropriate.