CASES

Case from CNC Onsite

Result: Generator and gearbox re-aligned

In January 2025, CNC Onsite responded to a urgent job at a 10 MW power plant in Denmark.

Challenge: The gearbox and the new generator were not aligned.

Caused by a sinking foundation, the gearbox was positioned seven millimeter lower.

CNC Onsite used its its 3D laser-scanner to analyse the structure. After one day, the newly- developed gantry precision machine successfully milled four areas on the foundation, achieving a 0.1 mm flatness.

CNC Onsite needed the skills of its technicians who were able to mill selected areas and offer advice.

The resulting connecting flanges between the gearbox and the generator were restored and aligned. Energy for the grid could soon resume.

The customer, Siemens Energy, had been contracted to set up the new generator, expressed satisfaction:

“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.

The complete drivetrain consisting of a gearbox and generator must be perfectly aligned. Any deviation can result in vibrations lowering the capacity to produce energy.

Thousands of consumers and several industries in mid-Denmark depend on the electricity and heating from this power plant.

The cause of the problem: The foundation for the gearbox and generator was sinking. The 30-year-old generator was replaced and this was when Siemens Energy’s astute technicians assumed that the generator was positioned higher than the gearbox. This cannot be detected with the naked eye cannot. This was confirmed by the 3D laser trackers.

The job took three days to complete, potentially saving many months of downtime for the power plant, SK Energy. The gantry machine machined the foundation to level the position of the generator which was located higher than the gearbox.