Turbine blades are the most critical, and most stressed, components in a steam turbine. Moving blades (buckets) extract energy from steam, while stationary blades (nozzles) direct and accelerate the steam flow. Both are subject to erosion, corrosion, fatigue, and solid particle damage over the turbine's operating life.
AQ Process Systems sources and exports OEM-compatible replacement blades for impulse and reaction steam turbines across all stage configurations. We source blades manufactured to the original airfoil profiles, root geometries, and metallurgical specifications, ensuring correct aerodynamic performance and mechanical integrity after replacement.
All blades are supplied with material certificates, dimensional inspection reports, and NDE (non-destructive examination) documentation. We support blade replacement during planned overhauls, emergency outages, and turbine upgrade programmes.
| Component | Specification | Description |
|---|---|---|
| Moving Blades (Buckets) | ||
| HP Moving Blades | 12Cr martensitic SS, Stellite tipped | Fir-tree or T-root | High-pressure stage moving blades, precision-forged with integral or brazed shrouds and erosion-resistant tip coatings. |
| IP Moving Blades | 12Cr or 17-4PH SS | Various root forms | Intermediate-pressure stage moving blades with optimised profiles for wet steam conditions. |
| LP Moving Blades | Ti-6Al-4V or 17-4PH SS | Long last-stage blades | Low-pressure last-stage blades, the longest and most stressed blades in the turbine, often titanium for weight and erosion resistance. |
| Shroud Bands / Covers | SS or Stellite | Riveted or integral | Blade tip shrouds providing structural coupling between blades and controlling tip leakage. |
| Lacing Wire | SS or Stellite | Brazed or mechanically attached | Inter-blade lacing wires damping blade vibration and shifting natural frequencies away from operating speed harmonics. |
| Stationary Blades (Nozzles) | ||
| Nozzle Segments | SS 304/316 or 12Cr | Cast or fabricated segments | Stationary nozzle blade segments directing steam onto the moving blades at the correct angle and velocity. |
| Diaphragms | Cast or welded | Inner/outer ring with nozzle blades | Complete diaphragm assemblies, inner ring, outer ring, and nozzle blades, for impulse-type turbines. |
| Nozzle Plates (Control Stage) | Cr-Mo-V steel | Arc-admission segments | First-stage nozzle plates with individual arc segments controlled by governor valves for load regulation. |
| Blade Attachments & Fixings | ||
| Blade Root Blocks | Machined to OEM root geometry | Various types | Precision-machined blade root attachments, fir-tree, T-root, fork, and pin types matched to the rotor groove. |
| Blade Locking Devices | SS or alloy steel | Caulking strips, locking pins | Blade retention hardware, caulking strips, tangential locking pins, and axial locking devices. |
| Erosion Shields | Stellite 6B or satellite strips | Brazed to leading edge | Leading-edge erosion shields protecting LP blades from wet steam droplet impact erosion. |
Parts are manufactured to OEM specifications with full material certification, dimensional inspection, and NDE documentation as required. Provide the turbine manufacturer, frame/model designation, and part number for precise identification.
We supply moving blades (buckets) for HP, IP, and LP stages, stationary blades (nozzle segments), complete diaphragm assemblies, control-stage nozzle plates, shroud bands, lacing wire, erosion shields, and all blade attachment hardware. Blades are manufactured to OEM airfoil profiles and root geometries.
Replacement blades are manufactured using the original blade drawings or by reverse-engineering from sample blades. Critical dimensions include the airfoil profile (pressure and suction side contours), root geometry (fir-tree, T-root), blade length, pitch, stagger angle, and throat opening. All blades are moment-weighed and matched in sets.
HP and IP blades typically use 12% chromium martensitic stainless steel (X20Cr13 or similar) for high-temperature strength. LP last-stage blades may use titanium alloy (Ti-6Al-4V) for weight reduction and erosion resistance, or 17-4PH precipitation-hardened stainless steel. Erosion shields are Stellite 6B brazed to the leading edge.
Yes. We supply OEM-compatible replacement blades for all major steam turbine manufacturers including Siemens (KWU), GE, Mitsubishi (MHI), BHEL, Triveni, Toshiba, Doosan, and others. Parts are identified by the turbine model, stage number, and blade drawing or part number.
Standard blade sets for common turbine models are available in 8-16 weeks. Custom or reverse-engineered blades may require 16-24 weeks including pattern development, forging, machining, and quality documentation. Emergency supply can be arranged for critical outage situations.
Share your turbine make, model, and part numbers, we respond within 24 hours.