FITNESS FOR SERVICE ANALYSIS

Petro Chemical

Petro Chemical

Background​

• Separator nozzle N1 was suffering from crevice corrosion due to moisture ingress via the weep hole in the reinforcement pad.
• Preliminary code calculations were not fully conclusive as to the fitness for service of this item and therefore a Level 3 assessment using a linear elastic Finite Element Analysis (FEA) model was built.

Outcomes​

• The maximum stress utilisation was evaluated to be 91.8% and is based on the
  current estimated remaining wall thickness (RWT) of 9.6mm with no future corrosion
  allowance (FCA) included.
•  The nozzle was verified against the loads provided by operator and found to be fit for
  service in the current state.
• The fracture mechanics assessment revealed on the FAD that the equipment was
  safe.