PSI - Issue 3

J.L. González et al. / Procedia Structural Integrity 3 (2017) 48–56 Author name / Structural Integrity Procedia 00 (2017) 000–000

55

8

s y h E t F  s

(18)

Substituting values:

8" 1"

29000

ksi

8  

27.6



38

ksi

8 ≤ 27 . 6

Therefore the stringers are strong enough. 5. Performance of the rehabilitated ring.

The recommended rehabilitation of the creep damaged ring of the stripper section of the FFC catalyser regenerator was accepted and installed, and the internal refractory lining was repaired, so the plant was started back in approximately 20 days after the shut down due to the detection of the overheating. Since then the FCC plant has operated without incidents. In July 19th, 2013 the authors visited the plant and made a visual inspection of the rehabilitated section, finding it in good condition, as can be seen in Figure 5. The last report of the reactor condition was received by December, 2015, with similar results, that is, no visible deformations, nor leaks or cracks.

Fig. 5. External view of the FCC catalyst regenerator reactor showing a good condition of the rehabilitated section (indicated with the red rectangle). Summary and conclusions 1. The shell of the striper section of a FCC reactor in an oil refinery that was severely overheated due to the fall of the internal refractory lining, as a consequence the affected section was plastically deformed and the material strength was reduced, both to unacceptable values. Since it was not possible to shut down the FCC plant immediately after the overheating was detected, the plant operator asked for an operating window up to a point