PSI - Issue 3

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

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just before failure and after that, a rehabilitation recommendation to put the reactor back in service as soon as possible. 2. The estimation of the creep rupture time was 730:14 h, which gave an operation window of 30 days, which was slightly surpassed by the operator. After that the plant was shut down and the reactor was inspected to verify that indeed the stripper section had gone into the creep regime deformation, causing severe strength reduction, metallurgical damage and shell distortion, but without catastrophic failure, so the damaged ring was suitable for rehabilitation. 3. The proposed rehabilitation method consisted on the installation of an external reinforcement consisting of an orthogonally stiffened set of four circumferential rings and twelve longitudinal (vertical) stringers. The ability of the reinforced ring was verified by calculation of the minimum required thickness as for section UG-27 of the ASME Secc. VIII Division 1 and the buckling strength calculated as for the API BULL 2U. 4. Since the rehabilitation described here, the FCC catalyst regenerator reactor has operated continuously without any incidents or failures. Acknowledgements The authors acknowledge “Pemex Refinación” for the opportunity to perform the work described in this paper. References Bulletin API 2U Third Edition, 2004: Bulletin on Stability Design of Cylindrical Shells. American Petroleum Institute, Washington, D.C. 20005. Code ASME Section VIII Division 1 2001: Rules for Construction of Pressure Vessels. The American Society of Mechanical Engineers, New York, NY 10016-5990. Standard API 579/ASME FFS-1, 2007: Fitness for Service. American Petroleum Institute, Washington, D.C. 20005. Standard API 510 Ninth Edition, 2008: Pressure Vessel Inspection Code: In-Service Inspection, Rating, Repair, and Alteration. American Petroleum Institute, Washington, D.C. 20005.