Interbed heat Exchanger tubes in Ammonia Synthesis Converter. 1

[SUNIL GOPAL SALIAN]

I have observed an longitudinal cracks in the interbed heat exchanger tubes of a Ammonia Synthesis converter. Several number of tubes were visually found with longitudinal and branch type cracks .I will be sharing the pictures which have taken during my project.
Please anyone be able to explain what could be the exact reason for this phenomenon.Has anybody came across this type of damage.

THIS IS THE LINK FOR THE PHOTO.

 

Please anyone be able to explain what could be the exact reason for this phenomenon.

Failure analysis is not done well by crowd sourcing on the www. That will require the services of a qualified metallurgical failure analyst, with input from plant maintenance and process engineering. The cost is minor when compared to another failure.
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Based on the photograph I suspect stress corrosion cracking, but that is just the mechanism, not the cause.
However I can warrant there is not a single 'exact' reason for this failure.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[georgeverghese]

Where are these longitudinal cracks appearing - at the bottom set of tubes on a horizontally oriented HX? Some of the questions one may ask are:
What is on the tubeside of this HX where these cracks are - feed gas or reactor exit gas?
How is the feedgas purified from CO, H2S before this HX ?
Is there any chance CO2 absorber solvent mist could have carried over into this HX ?