A wind turbine includes a main shaft rotatable around a rotation axis. The main shaft includes a first piece axially extending along the rotation axis, at least a second piece axially extending along the rotation axis, the second piece being axially adjacent to the first piece, a plurality of connections for fixing the second piece to the first piece.

A transmission gearing includes a sun gear, a planetary unit and a high speed unit. The sun gear is mounted on a slowly rotating gear shaft. The planetary unit includes a planetary toothed gear wheel and a planetary shaft gear wheel, which are both mounted on a planetary shaft. The planetary shaft gear wheel has a diameter that is larger than that of the planetary toothed gear wheel and smaller than that of the sun gear. The planetary toothed gear wheel engages the sun gear. The high speed unit includes a quickly rotating gear shaft on which a high speed shaft gear is mounted. The high speed shaft gear has a diameter that is smaller than that of the planetary shaft gear wheel. A drive belt engages both the planetary shaft gear wheel and the high speed shaft gear. The slowly rotating gear shaft is parallel to the planetary shaft.

A bearing arrangement for a wind turbine is provided, including a bed frame, a support structure mounted to the bed frame, a shaft, bearings supporting the shaft rotatably around a shaft axis, and bearing housings supporting one of the bearings respectively, wherein the bearing housings are mounted on opposite faces of the support structure, the faces facing in the axial direction with respect to the shaft axis. The bearing arrangement provides high bending stiffness. At the same time, the bearings in the bearings housings are easily accessible for maintenance, for example.

A transmission gearing includes a sun gear, a planetary unit and a high speed unit. The sun gear is mounted on a slowly rotating gear shaft. The planetary unit includes a planetary toothed gear wheel and a planetary shaft gear wheel, which are both mounted on a planetary shaft. The planetary shaft gear wheel has a diameter that is larger than that of the planetary toothed gear wheel and smaller than that of the sun gear. The planetary toothed gear wheel engages the sun gear. The high speed unit includes a quickly rotating gear shaft on which a high speed shaft gear is mounted. The high speed shaft gear has a diameter that is smaller than that of the planetary shaft gear wheel. A drive belt engages both the planetary shaft gear wheel and the high speed shaft gear. The slowly rotating gear shaft is parallel to the planetary shaft.

A wind turbine includes a main shaft rotatable around a rotation axis. The main shaft includes a first piece axially extending along the rotation axis, at least a second piece axially extending along the rotation axis, the second piece being axially adjacent to the first piece, a plurality of connections for fixing the second piece to the first piece.

A compressor crankcase assembly is provided for an air compressor. In one example, a compressor crankcase assembly includes a crankcase made of a material comprising at least 50% by weight aluminum and a crankcase liner disposed within the crankcase. The crankcase has a protrusion that is at least partially disposed within the groove of the crankcase liner.

A tower for a wind turbine, the tower including a plurality of tower segments including a first tower segment and at least a second tower segment, a plurality of buttresses, and an attachment piece. The tower segments are arranged one upon the other from the base of the tower to the top of the tower. The attachment piece is arranged between the first tower segment and the second tower segment, and the buttresses are attached to the attachment piece, such that loads which are acting on the tower segments are partially carried by the buttresses. A wind turbine comprising such a tower is also provided.

A compressor crankcase assembly is provided for an air compressor. In one example, a compressor crankcase assembly includes a crankcase made of a material comprising at least 50% by weight aluminum and a crankcase liner disposed within the crankcase. The crankcase has a protrusion that is at least partially disposed within the groove of the crankcase liner.