Abstract: A wind turbine is provided, including a hub, rotor blades, wherein each rotor blade is rotatably supported at or in the hub by a pitch bearing, a pitch control device for changing a pitch angle of the rotor blades, and a measurement system for capturing a sensor signal in or at the pitch bearing and for changing the pitch angle by the pitch control device as a function of the sensor signal to prevent failure of the pitch bearing due to a lack of lubrication, wherein the sensor signal represents a change in vibration, noise and/or temperature in or at the pitch bearing. Due to the fact that the pitch angle can be changed as a function of the sensor signal, lubrication of the pitch bearing is ensured throughout the lifetime of the pitch bearing. Unnecessary pitch movements can be prevented.

Abstract: A method of controlling a pitching system of a rotating rotor blade of a wind turbine includes: controlling the pitching system such that unintended pitching due to gravity is reduced.

Abstract: Provided is a wind turbine rotor blade pitch bearing for mounting a rotor blade to a hub, including a carrier with an annular arrangement of bearing pad seats; a plurality of bearing pads, wherein a bearing pad is arranged in each bearing pad seat of the carrier; and a gripping assembly for gripping the carrier, which gripping assembly including a sliding part arranged to lie against an annular arrangement of bearing pads and further includes an access window dimensioned to expose a bearing pad when opened. A wind turbine with a number of such pitch bearings; and a method of performing a service routine on a wind turbine rotor blade pitch bearing is further provided.

Abstract: A wind turbine is provided, including a hub, rotor blades, wherein each rotor blade is rotatably supported at or in the hub by a pitch bearing, a pitch control device for changing a pitch angle of the rotor blades, and a measurement system for capturing a sensor signal in or at the pitch bearing and for changing the pitch angle by the pitch control device as a function of the sensor signal to prevent failure of the pitch bearing due to a lack of lubrication, wherein the sensor signal represents a change in vibration, noise and/or temperature in or at the pitch bearing. Due to the fact that the pitch angle can be changed as a function of the sensor signal, lubrication of the pitch bearing is ensured throughout the lifetime of the pitch bearing. Unnecessary pitch movements can be prevented.

Abstract: Provided is a bearing arrangement for a wind turbine, including a first portion, a second portion, and a sound wave sensor which is configured to detect a thickness of the second portion, wherein one of the first portion and the second portion is movable relative to the other of the first portion and the second portion. In contrast to known bearing arrangements for wind turbines, the thickness of the second portion which for example is exposed to wear may be actively detected. Thus, the information of the thickness is available at any time. Thus, a demand of an exchange of the second portion can be precisely predicted and determined.

Abstract: A method of monitoring a blade pitch bearing of a rotor blade of a wind turbine is provided, the method including: pitching the rotor blade; measuring an amount of a vibration of the blade pitch bearing during the pitching; estimating a condition of the blade pitch bearing based on the measured amount of vibration. Also disclosed is an arrangement for monitoring a blade pitch bearing, a rotor blade bearing and a wind turbine.

Abstract: Provided is a wind turbine including a hub and several blades rotatably attached to the hub by means of blade bearings including an inner ring coupled with the respective blade and an outer ring coupled with the hub, or vice versa, and rolling elements provided between the rings, wherein the outer ring or the inner ring has a cross section with a circumferentially varying thickness.

Abstract: Provided is a wind turbine rotor blade pitch bearing for mounting a rotor blade to a hub, including a carrier with an annular arrangement of bearing pad seats; a plurality of bearing pads, wherein a bearing pad is arranged in each bearing pad seat of the carrier; and a gripping assembly for gripping the carrier, which gripping assembly including a sliding part arranged to lie against an annular arrangement of bearing pads and further includes an access window dimensioned to expose a bearing pad when opened. A wind turbine with a number of such pitch bearings; and a method of performing a service routine on a wind turbine rotor blade pitch bearing is further provided.

Abstract: A spherical body inspection apparatus including a support arrangement realized to support a spherical body during an inspection procedure; a probe arrangement comprising a plurality of ultrasonic testing probes arranged about the spherical body such that the ultrasonic testing probes target a common test point at the surface of the spherical body; and a displacer for effecting at least one relative rotational displacement between the spherical body and the probe arrangement. Also described is a method of inspecting a spherical body.

Abstract: A test rig to test a radial bearing including a first raceway, a second raceway and a plurality of rolling elements which are arranged between the first raceway and the second raceway. The test rig includes a section of the first raceway, a section of the second raceway and one or several of the plurality of rolling elements, wherein the section of the first raceway is arranged opposite to the section of the second raceway, the rolling elements are arranged between the section of the first raceway and the section of the second raceway, and the rolling elements are in contact with the sections of the first raceway and second raceway, and a means for applying load on the section of the first raceway and means for moving the section of the first raceway and the section of the second raceway relative to the one or several rolling elements.

Abstract: A blade pitch arrangement of a wind turbine is provided having a number of blade shafts extending radially outward from a hub and a rotor blade mounted around each blade shaft, which blade pitch arrangement includes a toothed ring arranged at the root end of each rotor blade; and a pitch drive unit for each rotor blade, having a driver body and a pinion realized to engage with the toothed ring of a rotor blade; wherein a pitch drive unit is arranged relative to its corresponding rotor blade such that the pinion is positioned closest to the hub, and the driver body extends in a direction radially outward from the hub. A wind turbine is also described.

Abstract: Provided is a method for corrosion protection in bolt holes of a wind turbine, whereby a sleeve made of a corrosion resistant metallic material is inserted into the bolt hole, in particular covering the whole length of the bolt hole wall, and at least partly expanded using an expander tool to be fixed in the bolt hole.

Abstract: Provided is a bearing arrangement for a wind turbine, including a first portion, a second portion, and a sound wave sensor which is configured to detect a thickness of the second portion, wherein one of the first portion and the second portion is movable relative to the other of the first portion and the second portion. In contrast to known bearing arrangements for wind turbines, the thickness of the second portion which for example is exposed to wear may be actively detected. Thus, the information of the thickness is available at any time. Thus, a demand of an exchange of the second portion can be precisely predicted and determined.

Abstract: A method of monitoring a blade pitch bearing of a rotor blade of a wind turbine is provided, the method including: pitching the rotor blade; measuring an amount of a vibration of the blade pitch bearing during the pitching; estimating a condition of the blade pitch bearing based on the measured amount of vibration. Also disclosed is an arrangement for monitoring a blade pitch bearing, a rotor blade bearing and a wind turbine.

Abstract: Provided is a wind turbine including a hub and several blades rotatably attached to the hub by means of blade bearings including an inner ring coupled with the respective blade and an outer ring coupled with the hub, or vice versa, and rolling elements provided between the rings, wherein the outer ring or the inner ring has a cross section with a circumferentially varying thickness.

Abstract: A spherical body inspection apparatus including a support arrangement realized to support a spherical body during an inspection procedure; a probe arrangement comprising a plurality of UT probes arranged about the spherical body such that the UT probes target a common test point at the surface of the spherical body; and a displacer for effecting at least one relative rotational displacement between the spherical body and the probe arrangement. Also described is a method of inspecting a spherical body.

Abstract: Provided is a wind turbine including a rotor with a hub and several rotor blades arranged at the hub with the rotor blades being rotatable around an axis relative to the hub by a pitch bearing arrangement, whereby each rotor blade extends into the hub with a blade section, with the pitch bearing arrangement including a first and a second rolling bearing being spaced apart from each other in the direction of the axis and arranged between the blade sections and the hub.

Abstract: A test rig to test a radial bearing including a first raceway, a second raceway and a plurality of rolling elements which are arranged between the first raceway and the second raceway. The test rig includes a section of the first raceway, a section of the second raceway and one or several of the plurality of rolling elements, wherein the section of the first raceway is arranged opposite to the section of the second raceway, the rolling elements are arranged between the section of the first raceway and the section of the second raceway, and the rolling elements are in contact with the sections of the first raceway and second raceway, and a means for applying load on the section of the first raceway and means for moving the section of the first raceway and the section of the second raceway relative to the one or several rolling elements.

Abstract: A blade pitch arrangement of a wind turbine is provided having a number of blade shafts extending radially outward from a hub and a rotor blade mounted around each blade shaft, which blade pitch arrangement includes a toothed ring arranged at the root end of each rotor blade; and a pitch drive unit for each rotor blade, having a driver body and a pinion realized to engage with the toothed ring of a rotor blade; wherein a pitch drive unit is arranged relative to its corresponding rotor blade such that the pinion is positioned closest to the hub, and the driver body extends in a direction radially outward from the hub. A wind turbine is also described.

Abstract: A wind turbine blade bearing is disclosed. The bearing includes a first ring being connectable to a wind turbine rotor blade; a second ring being connectable to a hub; and a number of elements for transferring forces between the first ring and the second ring. The second ring includes a number of shear pins for additionally connecting the second ring to the hub.