13 May AUSTRALASIAN HRSG USERS GROUP (AHUG) 2013
HRSG AND WATER/STEAM CYCLE PRESERVATION AT TCC
Presentations by Anita Zunker, PEI, with Contact Energy
1. Outlines the process of development of a preservation strategy for the Taranaki Combined Cycle (TCC) Power Plant for Contact Energy
2. Identifies the key components to developing a successful preservation strategy
P91 – 304H DISSIMILAR METAL WELD INSPECTION FINDINGS
The P91 – 304H HP Steam dissimilar metal weld (DMW) – 300NB 31.75mm thick – had been identified for some time as the highest risk weld on the Contact Energy TCC site.
The unit was commissioned in 1999, inspected 3 times since commissioning. Due to lack of findings from these inspections, the inspection period had been relaxed and was scheduled for approximately 2 years time. After discussions at conferences (AHUG conference 2012, Alstom notification re HP OTC DMW welds), it was identified that this weld was the oldest and thickest of its type in service. It was identified that it was overdue to fail. As a results of these discussions, the next planned inspection of this DMW was bought forward to the next opportunity. This presentation discusses the findings.