Rotor Discs, Shafts & Balance Components
- GT13E2 rotor assemblies require precision-machined discs, shafts, and retaining hardware for safe high-speed operation.
- ZURN Power supplies compressor and turbine rotor components manufactured to tight tolerances.
- Each part is checked for material integrity, dimensional accuracy, and dynamic balance compatibility.
Manufacturing Precision & Materials
- Rotor discs and shafts are forged from high-strength alloy steels and nickel-based superalloys.
- CNC machining, grinding, and heat treatment processes follow OEM material and geometry standards.
- Full material traceability and NDT reports are provided on request.
Repair, Balancing & Reassembly
- We offer rotor inspection, rebalancing, and component replacement services.
- Damaged discs and shafts can be evaluated for repair or replacement recommendations.
- Reassembled rotor components are checked for runout and balance before release.
Request a Quote
- Submit rotor component drawings, part numbers, or photos for technical review.
- Our engineers will advise on repairability, lead time, and cost-effective alternatives.
- Email sales@zurnpower.com for GT13E2 rotor component pricing.
GT13E2 Turbine Rotor Assembly
The GT13E2 turbine rotor consists of 5 stages of turbine blades mounted on individual discs, connected by curvic couplings and bolted to form the rotor stack. The rotor operates at 3,000 RPM (50 Hz) or 3,600 RPM (60 Hz), with inlet gas temperatures exceeding 1,100 C. Rotor integrity is the single most critical factor in turbine safety and availability.
| Parameter | Specification |
|---|---|
| Rated speed | 3,000 RPM (50 Hz) / 3,600 RPM (60 Hz) |
| Turbine stages | 5 (Stage 1 = HP, Stage 5 = LP) |
| Blade count per stage | ~96-128 (varies by stage) |
| Max gas inlet temperature | 1,100-1,140 C (depending on variant) |
| Disc material | Inconel 718 (Stages 1-3), CrMoV steel (Stages 4-5) |
| Blade attachment | Fir-tree dovetail (4-6 lobes) |
| Rotor weight | ~25 metric tons (complete turbine rotor) |
Turbine Disc Materials & Life Management
Rotor discs are the most safety-critical components in the gas turbine. The GT13E2 uses different materials depending on stage operating temperature:
| Stage | Disc Material | Max Temp | Life Limit |
|---|---|---|---|
| Stage 1 (HP) | Inconel 718 (forged) | 650 C | 100,000 hours / 2,000 starts |
| Stage 2 | Inconel 718 (forged) | 600 C | 150,000 hours / 3,000 starts |
| Stage 3 | Inconel 718 (forged) | 550 C | 200,000 hours / 5,000 starts |
| Stage 4 | CrMoV steel (forged) | 450 C | 300,000 hours / 10,000 starts |
| Stage 5 (LP) | CrMoV steel (forged) | 400 C | 300,000 hours / 10,000 starts |
Disc life is managed through a combination of creep tracking, low-cycle fatigue (LCF) monitoring, and periodic NDT inspection. ZURN Power supplies replacement discs with full material pedigrees, including melt origin, forging records, heat treatment curves, and mechanical property test results.
Common Rotor Failure Modes
- Disc bore cracking (LCF): Low-cycle fatigue cracks initiate at the disc bore or rim bolt holes due to start-stop cycles. Ultrasonic inspection at every major overhaul (24,000 hours). Critical safety item - cracked discs require immediate replacement.
- Blade root cracking: Fir-tree dovetail roots develop fretting fatigue cracks at lobe contact surfaces. Caused by inadequate lubrication, vibration, or improper assembly. Eddy current + fluorescent penetrant inspection at each blade removal.
- Creep elongation: HP stage blades gradually elongate under centrifugal load and temperature. Measure blade length at each inspection; discard blades exceeding 0.5% growth.
- Bolt hole elongation: Curvic coupling bolts and holes experience fretting and plastic deformation. Monitor bolt torque and hole geometry at rotor disassembly.
- Thermal distortion: Uneven cooling causes disc warpage. Run-out measurement at rotor assembly; maximum TIR (Total Indicator Reading) 0.05 mm.
Rotor Repair & Refurbishment Capabilities
ZURN Power provides comprehensive rotor repair services either on-site or at our manufacturing facility. Our capabilities include:
- Disc refurbishment: Bolt hole reaming and sleeving, curvic coupling re-machining, bore ultrasonic inspection and machining
- Blade replacement: Full stage blade replacement with moment-weight sorted sets; rotor balancing to ISO 1940 Grade 2.5
- Rotor stacking: Precision re-stacking with run-out optimization; curvic coupling optimization for minimum stack eccentricity
- On-site services: Rotor extraction, inspection, and blade replacement at customer site using portable tooling
- Balance validation: High-speed balance in our balance bunker (up to 4,500 RPM); vibration acceptance per API 616
For rotor inquiries, provide the GT13E2 serial number, operating hours, start count, and last major overhaul date. Our engineering team will recommend inspection scope and spare parts based on remaining life calculations.
Quality Assurance & Safety
Rotor components are manufactured under ISO 9001:2015 and AS9100D. Additional safety controls for critical rotating parts:
- Material pedigree: Full traceability from melt to finished disc (AMS 5662 for Inconel 718)
- Ultrasonic inspection: 100% volumetric UT on all disc forgings per ASTM E2375
- Surface NDT: Fluorescent penetrant + eddy current on all machined surfaces
- Mechanical testing: Tensile, creep, and LCF testing on material coupons from each heat lot
- Dimensional verification: CMM inspection of bolt hole patterns, curvic teeth, and bore geometry
- Balance certification: Final balance report with residual unbalance values per plane