Steam turbine repairs

GE’s rotor straightening solution includes an engineering root cause analysis, assessment and computer modeling, and recommendations based on the condition of the rotor.

How we repair your rotor:

• Shaft end thermal straightening
• Rotor machining
• High-speed balance

Combining outstanding rotor weld experience with world-class technical knowledge, Global Repair Solutions (GRS) has the technical experience to return damaged rotors back into service with both long- and short-term solutions.

Key Benefits

• Use your existing rotor: Significant lead time and potential cost savings when compared to rotor replacement.
• Proprietary technology: Restores your rotor back to design intent.
• Repair only what needs to be fixed: Flexible repair options that can pinpoint partial section, component, and spot welding.
• FineLine* rotor dovetail repair replaces forging with forging + welds, located in a lower stress location for improved service life of repair.

As part of the repair process, the damaged exit side of the steam path and sidewalls is machined so that it is returned to the transition point of the partition, typically about one-third of the depth. The removed steam path side is then replaced with new partial partitions and sidewalls.

Key benefits:

• Steam path repair process eliminates about 95% of the manual hand grinding and restores the steam path to its original geometry.
• Our repair process can lower the overall repair cost by up to 20%.
• Custom-machined partial partitions to restore steam path areas back to original condition.
• Patent pending GE proprietary technology.
• Higher recoverable losses compared to standard weld repair.

GE conducted a study to look at several dishing repair methods and the effect they have on long term dishing. Using ANSYS and GE proprietary modeling techniques, the study was performed on typical third-stage HP and IP diaphragms from medium-sized turbines. The results show that GE’s Power Services solution can offer a more than 50% reduction in creep over time vs. a bridge repair, and better results were observed in comparison to pure heat straightening.

Key Benefits

• Helps remove existing dishing and restores original axial alignment
• Reduces cycle time up to 45%
• Reduces future dishing through enhanced features
• Addresses TIL-1589 (D11)
• Includes a medium cost repair option
• Provides GE proprietary technology (patent pending)