Summary
Every gas turbine rotor eventually reaches the service limits its original equipment manufacturer published for it. For GE A, B, C, and E class machines, those limits are 200,000 factored operating hours and 5,000 factored starts; for F-class rotors, 144,000 factored hours, per TIL-1576 and GER-3620. Reaching a limit does not mean the rotor is worn out; it means a conservative, fleet-wide boundary has been crossed, leaving the owner with a capital replacement decision and no unit-specific evidence to support it. Structural Integrity’s Rotor Life Extension (RLE) program offers an economical alternative to replacement: extend the useful service life of the rotor you already own, on evidence drawn from that rotor’s actual condition and operating history.
RLE works because SIA couples three things most providers offer only in isolation — OEM-equivalent shop services, advanced inspection, and client-focused engineering. SIA’s partnership with Sulzer Turbo Services brings proven turbine shop, repair, and component replacement manufacturing equivalent to OEM work, performed alongside SIA’s own advanced nondestructive examination and turbine and generator engineering. Decades of rotor design and fleet management experience—hundreds of rotors analyzed across every major manufacturer—feed a probabilistic rotor evaluation that combines inspection findings, physics-based analytical life assessment, and real variation in material, production, operation, and inspection, rather than a single deterministic number.
The program is structured in three tiers so scope matches risk tolerance and capital plan. Tier 1 is pre-evaluation and engineering assessment: a review of operating data and history characterizing risk component by component, followed by a component-specific degradation assessment run against fleet bounds or tailored to the unit. Tier 2 moves the rotor into the shop for complete unstacking, dimensional evaluation, and cleaning, then comprehensive conventional and advanced NDE for condition and service damage assessment, with standardized repair or component replacement, re-stacking, balancing, and shop reporting under one roof. Tier 3 delivers the life evaluation — inspection and metallurgical findings folded into component-specific probabilistic risk curves, with operating and re-inspection recommendations for the extension period and its HGPI and MI intervals.
What distinguishes the outcome from an OEM recommendation is the conversation around it. SIA frames safety risk, unplanned outage risk, and planned-outage inspection findings against the owner’s own risk thresholds, so decisions about disk rim and dovetail post indications, transient vibration, or component modification are made transparently rather than defaulting to forced replacement. Findings are supported by SIA’s full-service Metallurgical Laboratory for sample characterization, failure evaluation, and compressor inlet hygiene assessment, and carried into PlantTrack™ and SIIQ™ for fleet asset management and real-time condition tracking across the power generation fleet. Contact SIA to scope a gas turbine rotor life extension evaluation.