(49f) TLE Steam Side Corrosion Boiler Feed Water & TLEs : Avoiding Failures

This paper shows on the one hand an analysis of sudden failures occurring at the bottom section of the TLEs, caused by corrosion at the steam side and an overview of the proposed corrective actions. On the other hand best practices during operations and shutdown are presented to avoid such damages.

Several TLEs showed sudden failures of the tubes at the bottom section of the TLE caused by corrosion at the steam side. Heavy corrosion deposits, excessive magnetite layers and strongly diminished wall thickness were the results of a disturbed protective magnetite layer. A detailed investigation and root cause analysis, supported by the TLE-provider, resulted in a possible failure mechanism and a number of improvement proposals for the monitoring of the Boiler Feed Water quality and the required corrective measures to restore the normal operating conditions for the damaged TLE.

The analysis and investigations by the TLE-provider resulted in a number of best practices during operations and shutdown.