During the summer of 2008, a power plant performed a routine maintenance outage and discovered two cracks in the bore of their HP/IP rotor. The customer worked with the OEM to investigate the cracks in the rotor. The OEM recommended the following: perform a bottle-bore procedure, perform mechanical integrity calculations, and manufacture a new rotor in parallel. The duration of this repair would take over 24 months to complete. Alstom was contacted by the customer to supply repair recommendations. After an inspection of the unit and the boresonic data, Alstom proposed manufacturing a new replacement with a shorter lead-time. The process would involve join welding two stock forgings and adding some additional weld build up. The customer selected Alstom’s proposal, which could provide a replacement rotor in six months. The work scope included: join welding two rotor forgings together, shaft weld build up, extensive machining, and in parallel the manufacturing and installation 17 rows of turbine blades. This paper will discuss and document the case of the condemned HP/IP rotor.

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