Selection of indicators for assessment of overall, computed, and remaining service lives of production equipment

Abstract

Vessels and apparatus employed in the chemical and petrochemical industry (containers, heat exchangers, towers, scrubbers, reactors, tanks, and pipelines) do not contain redundant components; safety factors assigned during design for cases of wear, degradation of material properties, and other unforeseen situations therefore ensure their safe-operating lives. A reduction in safety factors will make it possible to judge how closely structural components and production equipment as a whole approach the limiting state. The standard safety factor serves as a reference point indicating just how closely the actual safety factor comes to the limiting state, and in the author’s opinion, can be adopted as the limiting allowable safety factor ensuring the safe operation of production equipment. Reserve-strength investigations conducted by the Angarsk Petrochemical Company over a number of years have demonstrated the versatility of dimensionless values of design, actual, and standard safety factors, and the possibility of their use as indicators for evaluation of overall, computed, (allowable) and remaining service life. Evaluation of the overall, computed (allowable), and remaining service lives is acceptable for design, fabrication, and appraisal of industrial safety as a technico-economic indicator serving to define safe-service lives assigned to production equipment.