Corrosion Failure Investigation-Case Study

The presentation of Wayne D. Niemeyer ( 2nd case starting from 17:00)  has demonstrated the importance of understanding of process and production chemistry for the corrosion root cause analysis(RCA). This principle is prompted by ASTM G161  Standard Guide for Corrosion-Related Failure Analysis

The most important observation from this case is to determine the chemistry of fluid not only  from  normal production, but also from upset stage. This could be a challenge in certain plant/process due to cost-saving practice by minimising “unnecessary” monitoring. RCA may run into the dead end without weekly lubricant sample been analysed. The final conclusion was leaking of high alkaline closed loop cooling water into lubricant stream causing rapid corrosion of aluminium surface. This conclusion is drawn by  results from both Scanning Microscopy with the weekly production fluid analysis

Lesson Learnt:

1. Laboratory analysis without understanding of the process for corrosion RCA often leads to inconclusive results;
2. Normal process condition, as well as upset condition should be carefully investigated for corrosion related RCA.

Reference

1. ASTM G161 Standard Guide for Corrosion-Related Failure Analysis
2. Wayne Niemeyer, Case Studies of Corrosion Failures