Down-tower was yesterday. Up-tower is today | Significant savings potential when overhauling bearing seats

If bearings required to drive the mechanical pump in a wind main gearbox need to be replaced, this is typically feasible to do on the turbine tower. The situation changes when the bearing seat is damaged. This occurs if the outer ring of the rolling bearing, normally fixed in the gearbox bore, has rotated.

Normally, repairs up-tower are not possible. The gearbox must be replaced, which is a labor-intensive and costly undertaking for operators - often 50 to 100 times higher than parts and installation costs.

But that was yesterday. Effective immediately, there is a practical, cost-effective up-tower repair solution for a wide range of NGC gearboxes. Using specialized tooling, repairs to damage on the tower can be performed in situ. To compensate for the loss of fit accuracy caused by impressing, a bearing insert is placed between the housing and the ring. The tolerance between the housing bore and the insert is chosen so that the insert fits tightly while simultaneously providing the required bore accommodation for a new bearing.

This solution has already proven itself in the field: bearing seats in the gearbox housing could be reworked, and the bearing inserts were put in place successfully. The concept is flexible enough to be applied to all NGC wind main gearbox types and additional components.