📌 Pulp & Paper Pump Impeller - Pitting corrosion in submerged brackish water

Industry: Pulp & Paper · Severity: Critical · Mechanism: Pitting corrosion · Risk: 97/100

🧾 Summary

A pump impeller used in a pulp & paper application shows pitting corrosion risk after exposure to submerged brackish water. The design review focuses on material pairing, geometry, coating coverage, inspection access, and realistic validation testing.

⚠️ Design Risk

Likely weak points include local electrolyte retention, incompatible material pairing, coating discontinuities, trapped debris, and missing acceptance criteria for corrosion validation.

🛠️ Recommended Controls

Recommended controls: drainage path redesign, sacrificial element review, and electrical isolation. Add drawing notes, supplier evidence requirements, and a validation plan that reflects the expected service environment.

🎓 Learning Notes

Learners should identify the corrosion mechanism, estimate severity, and decide whether prevention should come from material change, coating change, geometry change, sealing, isolation, or inspection planning.