Source page: SB-LWS-2025-11 Rev. A - Pitch Bearing Bolt Re-torque · Original file: original.pdf, p. 1 · Provenance: ✓ quote verified (native text)
Text
Litware Wind Systems - Service bulletin
FICTIONAL - NOT FOR OPERATIONAL USE
SB-LWS-2025-11 Rev. A - Pitch bearing bolt re-torque
Service bulletin issued by Litware Wind Systems on 2025-10-06.
Loose pitch bearing bolts were found on two LT-32 turbines at another site after three years of operation. A one-time re-torque of all bolts restores the preload.
1. Stop the turbine, lock the rotor and isolate the pitch system.
2. Use a hydraulic torque wrench calibrated within the last 12 months (accuracy +/- 3 %).
3. Re-torque 100 % of the pitch bearing bolts to 1,450 Nm in the cross pattern of the bolt map, blade by blade.
4. Mark each bolt with a paint line after re-torque.
5. Record every bolt that turns more than 60 degrees before reaching the torque and report it to Litware Wind Systems.
Record the turbine, blade, torque wrench serial number and the bolts that turned on the re-torque form and return it to Litware Wind Systems within 60 days.
Table t01
| Row | Field | Value |
|---|---|---|
| 2 | Bulletin number | SB-LWS-2025-11 |
| 3 | Revision | A |
| 4 | Issue date | 2025-10-06 |
| 5 | Category | Mandatory |
| 6 | Applies to | LT-32 turbines, all variants (M30 10.9 pitch bearing bolts, 72 per blade bearing, 216 per turbine) |
| 7 | Compliance | At the next 12-month service |