A method of lubricating a main bearing of a wind turbine, the method comprising providing the main bearing. The main bearing comprises a main bearing housing having one or more pre-existing lubrication ports, an outer race, an inner race radially disposed inwardly from the outer race, and a first row of roller bearings and a second row of roller bearings. The first and second rows of roller bearings are radially disposed between the inner race and the outer race. The first row of roller bearings is axially disposed on the upwind side of the second row of roller bearings. The method includes forming one or more alternate lubrication ports in the main bearing housing. The alternate lubrication ports are configured to deliver a lubricant between the first row of roller bearings and the second row of roller bearings. The method includes supplying the lubricant to the alternate lubrication ports.

CLEAN A wind turbine (100) with a rotor bearing (1) is proposed, wherein drainage chambers (7) on both sides of the rotor bearing (1) are connected to each other via a plurality of channels (5) traversing an outer ring (2) of the rotor bearing (1), which are distributed over the circumference of the outer ring (2) and that an axis (A) of the rotor bearing (1) is arranged at an angle in the range of 2 to 100 to the horizontal line (H) for promoting a flow of leakage oil through the channels (5).

Methods and devices for replacing used bearing grease in a main bearing of a wind turbine. Methods for purging used bearing grease from a main bearing of a wind turbine in an up-tower arrangement without removing the main bearing cover. Methods for purging used bearing grease from a main bearing of a wind turbine in an up-tower arrangement while rotating the main shaft and main bearing.

A wind turbine planet gear shaft has a shaft body with an outer surface, a segment of the outer surface being a slide bearing surface configured to form a radial slide bearing with an inner opening of a planet gear. The slide bearing surface has a first portion configured as a non-load-bearing zone and a second portion configured as a load-bearing zone and exactly one axially elongate oil pocket in the slide bearing surface, that oil pocket being located in the non-load-bearing zone. An oil supply channel in the shaft body has a first end in communication with the oil pocket, and first and second oil return channels in the slide bearing surface each have a first end at a longitudinal end of the oil pocket and a second end open to ambient air.

A method of lubricating a main bearing of a wind turbine, the method comprising providing the main bearing. The main bearing comprises a main bearing housing having one or more pre-existing lubrication ports, an outer race, an inner race radially disposed inwardly from the outer race, and a first row of roller bearings and a second row of roller bearings. The first and second rows of roller bearings are radially disposed between the inner race and the outer race. The first row of roller bearings is axially disposed on the upwind side of the second row of roller bearings. The method includes forming one or more alternate lubrication ports in the main bearing housing. The alternate lubrication ports are configured to deliver a lubricant between the first row of roller bearings and the second row of roller bearings. The method includes supplying the lubricant to the alternate lubrication ports.

Disclosed is a method and a device for independently pitching of a wind turbine. The method includes: driving a first gear using a pitch motor, such that a second gear meshed with the first gear drives a bearing inner ring to rotate to drive a paddle of a wind turbine connected to an outer side of the bearing inner ring, the bearing inner ring being connected to a root of the paddle of the wind turbine; inflating and pressurizing, using an air pump, an airbag to discharge a lubricating fluid from an interior of the airbag through discharge holes and connecting tubes; and the lubricating fluid flowing into an annular flow chamber through connecting holes, and flowing, through seepage holes, into a rotational gap between a bearing outer ring and the bearing inner ring.

Disclosed is a method and a device for independently pitching of a wind turbine. The method includes: driving a first gear using a pitch motor, such that a second gear meshed with the first gear drives a bearing inner ring to rotate to drive a paddle of a wind turbine connected to an outer side of the bearing inner ring, the bearing inner ring being connected to a root of the paddle of the wind turbine; inflating and pressurizing, using an air pump, an airbag to discharge a lubricating fluid from an interior of the airbag through discharge holes and connecting tubes; and the lubricating fluid flowing into an annular flow chamber through connecting holes, and flowing, through seepage holes, into a rotational gap between a bearing outer ring and the bearing inner ring.

A yaw-bearing grease tray for a wind turbine. The yaw-bearing grease tray includes an arcuate flat band portion with an inner arcuate sidewall, an outer arcuate sidewall, a first end wall and a second end wall which are perpendicular and disposed on the arcuate flat band portion. The yaw-bearing grease tray includes a ledge formed on the first end wall to be substantially parallel to the arcuate flat band portion and a step formed at the second end wall to be substantially parallel to the arcuate flat band portion. A plurality of magnets are disposed on the arcuate flat band portion to magnetically couple with yaw-bearing bolts and yaw-bearing nuts. In one example, the yaw-bearing grease tray is translucent. In another example, a field replaceable absorbent material is sized to fit within the arcuate flat band portion.

A method of monitoring the condition of a fluid-film bearing arranged to support the generator of a direct-drive wind turbine is provided. The method allows providing a hydrophone configured to convert acoustic noise to an output signal; immersing the hydrophone in the lubricating fluid of the fluid-film bearing; providing access to the hydrophone output signal at the exterior of the fluid-film bearing; and evaluating the hydrophone output signal to determine the condition of the fluid-film bearing. Disclosed embodiments further include a condition monitoring arrangement of a fluid-film bearing; and a direct-drive wind turbine comprising a fluid-film bearing and the condition monitoring arrangement.

A lubrication unit for a large bearing. Such large bearings may be used in wind turbines, and normally each bearing may be equipped with two, three, four, or more lubrication units. In particular, a decentralized lubrication unit for a large bearing is provided. A lubrication unit for a bearing comprises a container comprising a reservoir for lubricant and comprising an inlet and an outlet for lubricant, an inlet through which lubricant is supplied to the lubrication unit and an outlet through which lubricant is supplied to the bearing, means for fluidly connecting the lubrication unit to the bearing, wherein the lubrication unit is secured to a surface of the bearing during operation.