fir-tree blade fastening 枞树形叶片固定

axial fir-tree blade root 轴向枞树形叶根

annular fir-tree blade root 周向枞树形叶根 ; 周向装入的枞树形叶根

inverted fir-tree blade root 外包式枞树形叶根

fir-tree blade root 枞树形叶根

fir tree blade 锯齿叶片

annular fir tree blade root 周向的枞树形叶根

axial fir tree blade root 轴向装入枞树形叶根

fir-tree straddle root blade 外包枞树形叶根叶片