- Coal-fired, 4 x 550MW power station, located in the UK
Problem:
- Routine inspection revealed external cracking, typical of thermal fatigue, at the rotor inlet and internal cracking on the 200mm thick casing
Approach:
- Thermal stress analysis and fracture mechanics assessment
Benefits:
- Transient thermal stress distributions defined
- Coincidence of defects with high-stress locations confirmed
- Crack arrest predicted in the casing
- Insufficient life predicted for the rotor under current operational conditions
- A slower start-up procedure developed to reduce crack growth rates to a tolerable level