Plant:

• 8 x 5MW HP-IP turbines at a UK refinery, with 180,000 hours service

Objective:

• Rotor life assessment, prior to re-blading for 140,000 hours further operation

Approach:

• Sampling the cold ends of the three oldest rotors for chemical analysis and post-exposure creep testing to 5000h
• Stress analysis and creep life assessment

Benefits:

• Identified materials that were inferior to design specification
• Established the actual as-built creep properties
• Successful underwriting of 140,000h further operation