Cylinder Issues
Snapping cylinder rod
A snapping cylinder rod is a severe event caused by sudden or uneven load conditions. It often occurs without warning and can lead to immediate loss of pitch function. The consequence is typically unplanned downtime and increased safety exposure during recovery.
Understanding the Problem
Why can a cylinder rod snap?
Snapping is typically linked to how peak loads are introduced and distributed in the pitch system. During demanding operation, rapid load changes can concentrate tensile forces in the rod and its interfaces. If these load patterns are not controlled as intended, the risk of sudden failure increases.
Typical symptoms
Sudden loss of pitch movement
The affected blade no longer responds to pitch commands.
Immediate turbine stop
The event typically triggers a rapid shutdown due to loss of control.
Mechanical damage at the cylinder interface
Damage is often visible at or near the rod connection point.
Asymmetric blade position
One blade may remain in an abnormal position compared to the others.
Secondary damage in surrounding components
Loads may transfer into adjacent interfaces during the event.
Increased safety exposure during inspection and recovery
Uncontrolled blade position can complicate safe access.
Solution
Pretension kit
A pretension kit is used to establish controlled and defined load conditions in the cylinder assembly.
By introducing proper pretension, dynamic load peaks are reduced, and forces are distributed more evenly through the system.
This supports more stable operation during rapid pitch movements and load changes.
The approach is selected to reduce the risk of sudden rod failure while supporting safety, component lifetime and long‑term operational robustness.
