CREEP ASSESSMENT OF REFORMER TUBE BY ULTRASONIC ATTENUATION AND MICROSTRUCTURE ANALYSIS

HK40 alloy tubing is commonly used in petroleum reforming facilities for its
high temperature corrosion resistance. Unfortunately, the tubes can experience
failure and rupture during service caused by formation of voids in tube wall by creep
stress generated by the pressure differential, thermal gradient, excess temperature
exposed between the inside and outside diameters of the tube. Routine creep
monitoring and assessment of reformer tube is critical. Hence, it was required to
assess the condition of tubes in avoid and prevent the failure. The degree of
degradation can be assessed by monitoring microstructural changes which can be
correlated with possible ultrasonic attenuation. The objective of the study is to assess
creep damage based on ultrasonic attenuation and microstructural damage