Abstract: Wind turbines and wind turbine blades' maintenance devices and methods for introducing a solidifying substance into the inner cavity of wind turbine blades are provided. The method includes: (i) drilling coaxial apertures in a wind turbine blade opposite walls by a filing means comprising a drilling means, a rod and a core fixed together (ii) pushing out the drilling means through the created apertures so that the apertures in the core part of the filling means are located in the inner cavity of the blade; (iii) supplying a solidifying substance in the liquid or semiliquid form into the inner cavity of the blade; (iv) partially pulling or pushing out the filling means so that only the rod part of the filling means remains within the inner cavity of the blade; (v) cutting away the ends of the rod of the filling means from the outer sides of the wind turbine blade.

Abstract: An offshore wind turbine blade and tower maintenance devices and systems, more particularly, to the system for service tools positioning relative to the offshore wind turbine blade and tower. An arrangement for lowering and raising service tools used for offshore wind turbine blade and tower maintenance, having: a truss system, a rigging and a rigging pulling in and letting out means. The truss system, includes booms, pivotally attached to a supporting means, which are adapted to be leaned against or releasably fixed to a wind turbine tower or wind turbine tower mooring elements; wherein the rigging and a rigging pulling in and letting out means are operably connected with the truss system, so to allow lowering and raising service tools used for offshore wind turbine blade and tower maintenance.