A 10 MW power plant in Denmark experienced a critical drivetrain alignment issue during the installation of a new generator. The root cause was a gradually sinking foundation, which had caused the gearbox position to shift approximately 7 mm relative to the generator.

Accurate alignment between gearbox and generator is essential for reliable operation. Even small deviations can generate vibration, increase component wear, reduce efficiency, and potentially lead to costly downtime. As the misalignment could not be detected visually, Siemens Energy required a precise method to identify and correct the problem.

The Solution

CNC Onsite was mobilized to perform a complete assessment of the foundation using advanced 3D laser scanning technology. The measurements confirmed the alignment issue and identified the exact foundation areas requiring correction.

Using CNC Onsite’s newly developed gantry milling machine, technicians precision-machined four selected foundation areas directly on site. The process achieved a flatness tolerance of 0.1 mm, restoring the correct positioning of the generator and gearbox without the need for extensive foundation reconstruction.

The combination of high-precision measurement, on-site machining, and technical expertise enabled a fast and accurate repair solution.

The Results

Following the machining process, the connecting flanges between the gearbox and generator were successfully restored and realigned, allowing the power plant to resume operation.

Key outcomes included:

• Gearbox and generator alignment fully restored
• Foundation machined to an accuracy of 0.1 mm flatness
• Misalignment of approximately 7 mm corrected
• Project completed in just three days saving costly months of downtime for the power plant, SK Energy
• Power generation quickly returned to the grid
• Extended operational reliability of the drivetrain system

Perspectives

Siemens Energy

“The tolerance is lower than it was when we first installed the power plant 30 years ago. The technicians used their technical skills to hit the nail on the head. No two foundations are the same and you need teamwork for this job. My colleagues in Germany who selected the areas to mill were equally impressed.”

– Peter Bang, Service Manager, Siemens Energy

Long-Term Value

As power plants and industrial drivetrains age, foundation settlement can create alignment issues that threaten operational reliability and increase maintenance costs.

This project demonstrates how precision measurement combined with on-site machining can restore critical equipment alignment without major civil works. By correcting the foundation directly on site, operators can significantly reduce downtime, avoid costly component replacements, and extend the service life of existing assets.

For power generation facilities and heavy industries, this approach provides a fast, accurate, and cost-effective alternative to traditional foundation repair methods while ensuring optimal drivetrain performance.