System for craneless blade mounting and dismounting at wind turbines

System (1) for craneless blade (6) mounting and dismounting at wind turbines (2), wherein the system (1) at least comprises a blade tip beam (9) to be fixed at the blade (6) and a displaceable arranged blade supporting structure (15) to be connected with and to guide and secure the blade tip beam (9) while the supporting structure (15) is displaced in a substantially horizontal direction;

• where the blade tip beam (9) at least comprises a longitudinal beam (10) with a first end (11) and a second end (12) and where the blade tip beam (9) further at least comprises a first clamping device (13), where the beam (10) is adapted to be arranged substantially parallel to the lengthwise direction of a blade (6) with the first end (11) of the blade tip beam (9) extending in the same direction as the tip end of the blade (8), where the blade tip beam (9) further comprises a second clamping device (14) placed substantially perpendicular to the longitudinal beam and substantially parallel with and in the same direction as the first clamping device (13), and where each of the clamping devices (13, 14) is adapted to be clamped at least partially around the blade (6) in the crosswise direction of the blade (6);
• wherein the blade supporting structure (15) comprises a tiltable hopper device (28) adapted to receive and support said first end (11) of the blade tip beam (9) with a variable angle of the blade tip beam (9) during displacement of the blade supporting structure (15);
• wherein the blade tip beam (9) further comprises locking means capable of securing the blade tip beam (9) to the tiltable hopper device (28) of the blade supporting structure to the blade tip beam;
• wherein the system (1) further comprises equipment for hoisting and/or lowering the blade (6) by means of at least a first winch (16) placed on the ground and at least a first wire (17) for connection between the first winch (16) and the blade (6);
• wherein the first wire (17) is connected with the blade (6) at a root end (7) of the blade (6) or in a position between the root end (7) and the centre of gravity of the blade, for the blade (6) to hang substantially vertical;
• and
• wherein the connection between the first winch (16) and the blade (6) is effected via a hub (5) of the wind turbine (2) arranged at a nacelle (4) of the wind turbine (2).