| 摘要 |
A composite turbine blade 4 is attached to a hub 8 by threaded fasteners 6, 18, 20. An elongate oval access opening, recess or window 24 is formed in the blade, to allow access for tightening a nut 6 from outside of the blade. The opening may have rounded ends to avoid stress concentrations, and the nut 6 may act on a bearing element 30. The nut may comprise a multi jack-bolt tensioner (nut tensioner figures 2-5). The opening may be wider towards the outside of the blade, to improve access for a spanner or wrench, whilst maximising blade strength. Where the blade root narrows rapidly from the connection, the openings could be open ended (figure 4). The connection between the blade root and hub may be non-planar, e.g. part conical or part spherical (figure 4). |
