Análise de falhas baseado em engenharia da confiabilidade em trocador de calor do processo de ureia em planta petroquímica

Abstract

During more than 30 years of operation the high-pressure heat exchanger of the fourth stage of the carbonic gas compressor has shown leaking in the tubes during normal operation due to corrosive process in tube bundle, whose failure causes shutdown of the production process of urea generating great financial loss and high maintenance costs. The objective of this study was to combine analytical techniques of reliability engineering: Life Data Analysis; Simulation via Reliability Block Diagrams and; Analyzing repairable systems with Crow-AMSAA model for the evaluation of a process improved in the heat exchanger by replacement of bundles of stainless steel by carbon steel tubes. As a result it was confirmed that the improvement of the material of the beams improved the performance of the heat exchanger, however, the maintenance policy used in the modified system was contributing by increasing the concentration of failures.