Papers by Keyword: Coxing Box

Abstract: The paper presents and compares the results on the reliability and remaining life assessment of a reactor (coxing box) from a petrochemical plant. The reactor shell is made of 16Mo5 (W1.5423) steel, with a thickness of 25 mm, plated with 3 mm thick X6CrAl13 (W1.4002) stainless steel. The assessment was made in two steps. For preliminary remnant life assessment, specifications of section VII of the ASME code was used followed by iRiS‑Thermo expert system. Further, experimental creep and metallographic replica analysis were performed. Results comparison of the two methods applied revealed a reduction of the preliminary estimated remaining live obtained using metallographic replica analysis. Based on the results obtained, the possibility to extend the service duration of the coxing box in the safety condition, using current process parameters, with of 20.000 hours was highlighted.

Abstract: The paper presents an application according the reliability and remining life assessment of the reactor (coxing box) from a petrochemical plant, after failure in welding joint of plated shell from W1.5423 (16Mo5) steel with 25 mm thickness, plated with W1.4002 stainless steel with 3 mm thickness. The reactor failure it has associated with initial flaws from welding process, which have accelerated remaining life exhaustion. The assessment made in two steps. It has used VII section of ASME code specifications and iRiS-Thermo expert system for preliminary remaining life assessment. Concomitantly, it was performed the experimental creep and thermal fatigue testing. The program results have defined creep and thermal fatigue exhaustion and its remaining life at common creep-fatigue action, in condition of safety exploitation. It was emphasized the possibility of use an extra 40,000 hours of rehabilitated reactor in the safety condition of normal parameters.