Patent ID: 9651021
Date: 2017-05-16
CPC Classifications: B23P,B66D,F03D,F05B,Y02E,Y02P,Y10T

Claim:
1. A method for removing a rotor blade from atop a tower of a wind turbine, the method comprising: positioning the rotor blade being removed in a substantially six o'clock position; installing at least one up-tower pulley at an up-tower location of the wind turbine; attaching a pulley cable from a first ground winch over the up-tower pulley to the rotor blade; attaching a guide line from a second ground winch to an up-tower location of the wind turbine; securing a guide pulley to the guide line, wherein the guide pulley is configured to move along the guide line; securing a guide cable from the rotor blade to the guide line over the guide pulley and back to the rotor blade so as to control an orientation of the rotor blade relative to the tower as the rotor blade is being lowered; allowing the guide pulley and the guide cable to move along the guide line until the guide pulley and the guide cable reach an end of the guide line; rotating the rotor blade to a generally horizontal position when the guide pulley and the guide wire are located at the end of the guide line by lowering the blade root of the rotor blade via the pulley cable and the first ground winch; and, lowering the rotor blade in the generally horizontal position by coordinated winch operation to a location on or adjacent to a support surface of the wind turbine.