An impeller includes: a disc having a disc shape; a plurality of blades formed on a surface facing a first side in an axial direction of the disc; and a cover surrounding the plurality of blades. The cover includes: an inner circumferential surface connected to the blades with a diameter decreasing from the second side toward a first side in the axial direction; and a distal end surface extending from an end portion of the inner circumferential surface on the first side in the axial direction toward the outside in a radial direction and facing the first side in the axial direction. A front edge portion extends from a boundary between the inner circumferential surface and the distal end surface toward the inside in the radial direction.

A method of making a root end of a wind turbine blade is described. The root end has a root end surface that connects to a wind turbine hub via a pitch bearing when the blade is installed on a wind turbine, and the method comprises providing a plurality of bores in the root end of the blade, each bore extending axially into the blade and having an opening defined at the root end surface; providing a plurality of plugs, each plug having a substantially solid first end portion; inserting the plugs into the respective bores each to a depth whereby the first end portions of the respective plugs extend inside the bores and form a seal against an internal surface of the bore and a sacrificial portion of the first end portion of each plug protrudes from the opening of the respective bore at the root end surface; and machining the root end surface to form a substantially flat root end surface for interfacing with the pitch bearing, wherein the step of machining the root end surface comprises removing the protruding sacrificial portions of the protruding plugs leaving the remaining first end portions of the respective plugs substantially flush with the root end surface.

Method and apparatus for weighing an elongate object extending between a root end and a tip end thereof, said method including: providing a respective tip load measurement gauge and root load measurement gauge; and providing a suspending arrangement configured for suspending said elongate object from said tip load measurement gauge and from said root load measurement gauge; and suspending said object in a horizontal orientation; and recording a tip load and a root load from respective said load measurement gauges, said method being additionally characterised by: providing a weighing area; and fixing an inclinometer to said suspended blade and load gauge arrangement; and suspending said elongate object from said tip load gauge and from said root load gauge; and adjusting the horizontality of said elongate object in response to signals from said inclinometer prior to said step of recording said tip load and said root load. Alternatively, an inclinometer may be replaced by placing a first distance sensor at a first location on a ground surface; and placing a second distance sensor at a second location on said ground surface; and suspending said elongate object from said tip load gauge and from said root load gauge such that a said root end thereof is suspended proximate said first distance sensor and a said tip end thereof is suspended proximate said second distance sensor; and measuring a first distance between said first distance sensor and a said root portion of said elongate object and; and measuring a second distance between said second distance sensor and a said tip portion of said elongate object; and then adjusting the horizontality of said elongate object in response to said first and second distance readings prior to said step of recording said tip load and said root load.

A method for repairing a cabin air compressor outlet housing includes removing a journal bearing support sleeve in a cabin air compressor outlet housing, positioning a cylindrical insert within the cabin air compressor outlet housing, wherein the cylindrical insert has an outer diameter greater than an outer diameter of at least one portion of the removed journal bearing support sleeve, an inner diameter less than an inner diameter of at least one portion of the removed journal bearing support sleeve, and a length greater than a length of the removed journal bearing support sleeve, welding the cylindrical insert to the cabin air compressor outlet housing, and machining the welded cylindrical insert to form a replacement journal bearing support sleeve.

A wind turbine rotor blade (14) comprising a root portion (15) having a substantially cylindrical shape and a longitudinal axis (22), the root portion having a mounting face (25); a plurality of bores (26) in a wall of the root portion and extending from the mounting face into the root portion, the bores being configured to receive respective connecting means for connecting the wind turbine rotor blade to a wind turbine hub; wherein the plurality of bores are inclined at an angle relative to the longitudinal axis of the root portion to define a cone angle.

A method of manufacturing a fluid apparatus with flanges that are fastened together may include the following steps: fastening the flanges with a fastening member; introducing a fluid into an internal space of the fluid apparatus, and plastically deforming portions of the flanges that form seats for receiving the fastening member and portions of the flanges that form mating surfaces with pressure of the fluid being applied; releasing the fastening member and correcting at least the mating surfaces out of the seats and the mating surfaces; and refastening the flanges.

A method for manufacturing a root segment of a rotor blade of a wind turbine includes the steps of: providing multiple root segment sections of the root segment to be manufactured; drilling first holes into each one of the provided root segment sections to obtain drilled root segment sections; arranging the multiple drilled root segment sections in a mold; and casting the multiple drilled root segment sections arranged in the mold to obtain the root segment.

The invention relates to a method for securing a bushing in a blade root of a wind turbine blade according to the preamble of claim 1. The method is known in the state of the art. The known method uses an additional cavity in axial direction of the blade root. The cavities in axial and radial direction are used for accommodation of a T-bolt type bushing. The known method is not suitable for pen-type bushing. The invention has for its purpose to provide a method, which is suitable for securing a pen-type bushing in the blade root, which method can also be used to replace an existing pen-type bushing in a blade root.

The present disclosure is directed methods for manufacturing spar caps for wind turbine rotor blades. In certain embodiments, the method includes forming an outer frame or tray of the spar cap via at least one of three-dimensional (3D) pultrusion, thermoforming, or 3D printing. As such, the outer frame has a varying cross-section that corresponds to a varying cross-section of the rotor blade along a span thereof. The method also includes arranging a plurality of structural materials (e.g. layers of pultruded plates) within the pultruded outer frame of the spar cap and infusing the structural materials and the outer frame together via a resin material so as to form the spar cap. The resulting spar cap can then be easily incorporated into conventional rotor blade manufacturing processes and/or welded or bonded to an existing rotor blade.

Wind turbine bulkhead removal systems and methods are provided. The bulkhead removal system includes a bulkhead removal device and control subsystem. The bulkhead removal device includes a drilling subsystem with a drill for drilling at least one bulkhead within a wind turbine blade and an extension subsystem which is physically connected to the drilling subsystem and releasably securable to the wind turbine blade. The extension subsystem moves the drilling subsystem forwards and backwards along a length of the wind turbine blade to position the drill for drilling through each bulkhead. The control subsystem controls the operation of the drilling subsystem and the extension subsystem. The bulkhead removal system may also include a connection subsystem for connecting power and control components of the drilling and extension subsystems to a power source and to the control subsystem.