Numerical investigation of superheater tube failure

Industrial superheaters in petrochemical plants possess leakages due to failure in many areas. This paper presents the results of investigations into identifying the failure causes. The investigations were carried out by simulating the heating process of a superheater. The simulation was carried out numerically using ANSYS mechanical commercial software. The simulation results indicated that the superheater tubes were subjected to direct radiation heat transfer as well as flame violence. The leakage spots were formed due to cracks in the material mainly at the joint points between the tubes and the header. It was also realized that the welding at the connection areas of the pipes and the header had weakened the material and formed low thermal resistance spots which could not stand the 510 degrees C temperature and consequently, it had either melted or cracked.