Fabrication of Offshore Wind Turbine Stator Frames & Rotor Hubs
As global demand for renewable energy surges, wind turbines are scaling to unprecedented sizes—especially in the offshore sector. A tier-1 global energy equipment manufacturer contracted Openex Metal Fabrication to execute the heavy manufacturing of wind turbine generator (WTG) stator frames and heavy rotor hubs.
Due to the immense dynamic loads offshore turbines face over a 25-year lifespan, the client required 100% full-penetration, flaw-free welds alongside ultra-precise 5-axis CNC machining for the massive connecting flanges. Openex’s ability to manage plate rolling, welding, and 200-ton capacity machining under a single roof was critical to meeting the client's aggressive rollout schedule.
| Project Specifications | |
|---|---|
| Industry / Application | Renewable Energy / Offshore Wind Generation |
| Components Fabricated | Generator Stator Frames, Rotor Hubs, Nacelle Bedplates |
| Primary Materials | High-Strength Low-Alloy (HSLA) Steel S355 / S460 |
| Max Component Dimensions | 8.5 Meters Diameter | Weight: 125 Tons |
| Inspection Standards | 100% UT on structural welds, EN-1090 EXC4, ISO 3834-2 |
Execution & Manufacturing Process
Thick Plate CNC Rolling
The stator housings required rolling extreme-thickness S355 and S460 high-strength carbon steel plates perfectly to radius. Using our high-capacity 4-roll CNC plate rolling machines, we maintained absolute dimensional uniformity and circularity prior to tack welding.
Multi-Pass SAW & UT Inspection
Due to offshore fatigue requirements, Submerged Arc Welding (SAW) was heavily utilized. Positioning these 100+ ton sections on massive rotary rollers, our ASME-certified operators executed pristine, deep-penetration welds. A dedicated NDT team immediately verified all joints utilizing 100% Ultrasonic Testing (UT).
Precision Gantry & VTL Machining
After thermal stress relief, the stator structures required exacting parallelism across opposing mounting flanges to prevent internal turbine failure. We utilized massive CNC Vertical Turning Lathes (VTL) to hold extreme tolerances on parts measuring over 8 meters in diameter.
The Result
By keeping every major operation—cutting, heavy rolling, AWS certified welding, thermal stress relief, heavy CNC machining, and marine coating—under the roof of a single massive facility, Openex shaved 4 weeks off the client’s supply chain logistics. All wind turbine generator components successfully passed CE structural evaluations and have been successfully deployed offshore.