Method and apparatus for turning a rotor blade bearing on wind turbines without using a mobile crane
The invention relates to a method of servicing wind turbines having a hub containing a slewing ring bearing to which a rotor blade is fastened such that the pitch angle is adjustable. The rotor blade is brought into a position pointing vertically downward, lowered by means of threaded rods and hoisting means and attached suspendingly to the hub. The slewing ring bearing is then turned. The rotor blade is then hoisted again and fastened to the slewing ring bearing.
1. A method of releasing a rotor blade ( 200 ) of a wind turbine, wherein the rotor blade ( 200 ) is mounted during operation of the wind turbine on a hub ( 100 ) of the wind turbine by means of a slewing ring bearing ( 110 ) such that a pitch angle of the turbine blade is adjustable, and a movable slewing bearing part ( 120 ) is joined rotatably to the hub ( 100 ) and fixedly to a flange ( 210 ) of the rotor blade ( 200 ) by a plurality of threaded bolts, said method comprising the following steps:
positioning the rotor blade ( 200 ) in a position pointing at least approximately vertically downward as seen from the hub ( 100 ),
screwing in at least one threaded rod ( 300 , 310 , 320 ) into a tapped hole in the rotor blade flange ( 210 ),
holding the rotor blade, by means of a hoisting means ( 400 ) which is connected to the at least one threaded rod, in a position in which the rotor blade flange ( 210 ) abuts the slewing ring bearing ( 110 , 120 ),
releasing all of the threaded bolts,
lowering the rotor blade ( 200 ) by means of the hoisting means ( 400 ),
fastening at least one adapter ( 500 , 550 ) for holding the rotor blade ( 200 ) to the hub ( 100 ) and to the rotor blade ( 200 ) after the rotor blade ( 200 ) has been lowered, and
disconnecting the at least one adapter ( 500 , 550 ) from the rotor blade ( 200 ) and hub ( 100 ) prior to hoisting the rotor blade ( 200 ).
2. The method according to claim 1 , wherein at least one of the threaded bolts screwed into the tapped hole are unscrewed and removed before the at least one threaded rod ( 300 , 310 , 320 ) is screwed in.
3. The method according to claim 1 , wherein the plurality of threaded rods ( 300 , 310 , 320 ) which are each connected to a respective hoisting means ( 400 ) are each screwed into a respective tapped hole in the rotor blade flange ( 210 ).
4. The method according to claim 1 , wherein the at least one adapter ( 500 , 550 ) is attached to the hub ( 100 ) or to the rotor blade flange ( 210 ) by a second plurality of threaded bolts ( 600 , 650 ).
5. The method according to claim 1 , wherein the at least one adapter ( 500 , 550 ) comprises at least two adapters ( 500 , 550 ) attached to the hub ( 100 ) and to the rotor blade ( 200 ).
6. The method according to claim 1 , wherein a cable ( 700 ) for holding the rotor blade ( 200 ) is attached to the hub ( 100 ) and to the rotor blade ( 200 ) after the rotor blade ( 200 ) has been lowered.
7. The method according to claim 6 , wherein at least one guide rail is also mounted on the hub ( 100 ) and on the rotor blade ( 200 ).
8. The method according to claim 1 , wherein all the threaded rods ( 300 , 310 , 320 ) are unscrewed after fastening the at least one adapter ( 500 , 550 ) so that the rotor blade ( 200 ) is attached suspendingly to the hub ( 100 ).
9. A method of servicing a wind turbine, in which at least one rotor blade ( 200 ) used in operation of the wind turbine is mounted on a hub ( 100 ) of the wind turbine by means of a slewing ring bearing ( 110 ) such that a pitch angle of the rotor blade is adjustable, and a movable slewing bearing part ( 120 ) is joined rotatably to the hub ( 100 ) and fixedly to a flange ( 210 ) of the rotor blade ( 200 ) by a plurality of threaded bolts, said method comprising the following steps:
releasing the plurality of threaded bolts,
lowering the rotor blade ( 200 ) by means of the hoisting means ( 400 ),
turning the movable slewing bearing part ( 120 ) with respect to the rotor blade flange ( 210 ),
fastening the rotor blade ( 200 ) to the slewing ring bearing ( 110 , 120 ),
fastening at least one adapter ( 500 , 550 ) for holding the rotor blade ( 200 ) to the hub ( 100 ) and to the at least one adapter ( 500 , 550 ) after the rotor blade has been lowered,
disconnecting the at least one adapter ( 500 , 550 ) from the rotor blade ( 200 ) and hub ( 100 ) prior to hoisting the rotor blade ( 200 ), and
attaching the rotor blade ( 200 ) suspendingly to the hub ( 100 ).
10. The method according to claim 9 , wherein the rotor blade ( 200 ) is attached suspendingly to the hub ( 100 ) by unscrewing the threaded rods ( 300 , 310 , 320 ) after attaching the at least one adapter ( 500 , 550 ).
11. The method according to claim 9 , wherein the movable slewing bearing part ( 120 ) is turned by at least 100°.
12. The method according to claim 9 , wherein the step of attaching the rotor blade ( 200 ) comprises the following steps:
screwing at least one threaded rod ( 300 , 310 , 320 ) which is connected to a hoisting means ( 400 ) into a tapped hole in the rotor blade flange ( 210 ),
hoisting the rotor blade ( 200 ) by means of the at least one hoisting means ( 400 ),
fastening the rotor blade ( 200 ) to the movable slewing bearing part ( 120 ) by screwing in a plurality of threaded bolts.