EP-4735372-A1 - LIFTING DEVICE FOR TURNING A SHEAR WEB OF A WIND TURBINE BLADE

EP4735372A1EP 4735372 A1EP4735372 A1EP 4735372A1EP-4735372-A1

Abstract

A lifting device designed for turning of a shear web in wind turbine blades. The device enables the shear web, comprising a web body positioned between two mounting flanges, to be turned from a horizontal to a vertical orientation around a longitudinal axis extending through the centre of gravity. The lifting device comprises an elongated body with two attachment points, fixing devices to releasable engage the shear web near the mounting flanges. The lifting device further comprises first and second repositioning mechanisms that allow for flexible adjustment of the distances between the fixing devices and the respective attachment points along the elongated body. This feature facilitates the positioning of the shear web's centre of gravity between the attachment points, ensuring efficient lifting and handling during wind turbine blade assembly.

Inventors

NANGOI, Idryan Edmund

Assignees

LM Wind Power A/S

Dates

Publication Date: 20260506
Application Date: 20240611

Claims (16)

1. A lifting device for releasably engaging a shear web for a wind turbine blade to allow turning the shear web from a substantially horizontal position to a substantially vertical position substantially about a longitudinal axis of the shear web extending substantially through the centre of gravity of the shear web, the shear web having a first mounting flange, an opposing second mounting flange, and a web body arranged between the first mounting flange and the second mounting flange, wherein the lifting device comprises: a first attachment point for securing a line thereto; preferably a second attachment point for securing a line thereto; an elongated body extending from the first attachment point; a first fixing device secured to the elongated body configured to releasably engage the shear web at or adjacent to the first mounting flange; and a second fixing device configured to releasably engage the shear web at or adjacent to the second mounting flange; wherein the first and second fixing devices are secured to the elongated body and the lifting device comprises a first repositioning means for allowing adjustment of a distance between the first fixing device and the first attachment point along the elongated body, and comprises a second repositioning means for allowing adjustment of a distance between the second fixing device and the first attachment point along the elongated body so that the longitudinal axis of the shear web, when held at a first location along the longitudinal axis by the lifting device and when held at a second location spaced apart from the first location along the longitudinal axis by the lifting device, can be arranged a pre-defined distance from the first attachment point along the elongated body.
2. A lifting device according to claim 1, wherein the first fixing device comprises a first clamp preferably being configured for releasably engaging the shear web at the first mounting flange and/or wherein the second fixing device comprises a second clamp preferably being configured for releasably engaging the shear web at the second mounting flange.
3. A lifting device according to claim 2, wherein the first clamp and/or the second clamp comprises jaws configured to releasably engage the web body adjacent to the respective mounting flange, wherein the jaws are configured to define a space for accommodating the respective mounting flange when the shear web is held by the lifting device.
4. A lifting device according to claim 3, wherein the first and/or second clamp comprises a pultrusion arranged to extend into the space and configured for engaging the respective mounting flange when the shear web is held by the lifting device.
5. A lifting device according to according to any one of the previous claims, wherein the elongated body is a beam.
6. A lifting device according to any one of the previous claims, wherein the first and second repositioning means comprise a first and a second sliding element, respectively, configured for sliding along the elongated body towards and away from the first and second attachment points, respectively.
7. A lifting device according to any one of the previous claims, wherein the first and second repositioning means comprise first and second locking elements, such as a lock pin or a bolt, respectively, configured for selectively locking the position of the first and second sliding elements, respectively.
8. A lifting device according to claim 7, wherein the first and second repositioning means respectively comprise a first set of one or more holes and preferably a second set of one or more holes distributed along the length of the elongated body, wherein the first and second locking elements are configured for selectively attaching the first and second fixing devices along the elongated body using the first and second set of one or more holes, respectively.
9. A lifting assembly for releasably engaging a shear web for a wind turbine blade to allow turning the shear web from a substantially horizontal position to a substantially vertical position about a longitudinal axis of the shear web extending substantially through the centre of gravity of the shear web, the lifting assembly comprising: a plurality of lifting devices according to any one of the previous claims, wherein the first and second repositioning means of each lifting device allow adjustment of the distance from each of the fixing devices to the first attachment point so that, when the plurality of lifting devices are distributed and engaged along a longitudinal axis of the shear web, the longitudinal axis of the shear web is arranged at substantially the same pre-defined distance from the first attachment point of each lifting device; and a lifting beam comprising a plurality of lines corresponding to the number of attachment points of the plurality of lifting devices, wherein each line is attached to a dedicated attachment point and preferably one or more winches for selectively pulling the plurality of lines to allow lifting in the horizontal position and turning the shear web to the vertical position.
10. A lifting assembly according to claim 9, wherein the shear web is held at the first location by a first lifting device of the plurality of lifting devices and the at the second location by a second lifting device of the plurality of lifting devices.
11. A method of turning a shear web from a substantially horizontal position to a substantially vertical position about a longitudinal axis of the shear web extending substantially through the centre of gravity of the shear web, comprising the steps of: providing the shear web in the substantially horizontal position; providing a plurality of lifting devices according to any one of claims 1-8 or a lifting assembly according to any one of claims 9-10; distributing the plurality of lifting devices at respective positions along a longitudinal axis of the shear web; for each lifting device, adjusting the distance from each of the fixing elements to the first attachment point using the first and second repositioning means, and releasably engaging the fixing devices so that the longitudinal axis of the shear web is arranged at substantially the same pre-defined distance from the first attachment point at each lifting device; and applying a turning torque to the shear web via the first attachment point of each lifting device so as to turn the shear web substantially about the longitudinal axis from the substantially horizontal position to the substantially vertical position.
12. A method according to claim 11, wherein the shear web can be turned both clockwise and counterclockwise.
13. A method according to any one of claims 11-12, wherein the shear web is provided on one or more supports, and wherein, prior to applying the turning torque, the method comprises a step of applying a lifting force to the first and second attachment points of each lifting device so as to lift the shear web up from the one or more supports.
14. A method according to any one of claims 11-13, wherein the turning torque is applied by attaching a line, preferably of the lifting beam of the lifting assembly, to the first attachment point of each of the plurality of lifting devices.
15. A method according to any one of claims 11-14, wherein the step of distributing the plurality of lifting devices comprises arranging the elongated body above or below the shear web, and arranging the fixing devices on the elongated body, for example sliding the sliding elements of the fixing devices onto the elongated body.
16. A method of manufacturing a wind turbine blade, comprising the steps of: moulding a shear web in a shear web mould; demoulding the shear web from the shear web mould preferably by arranging the shear web on one or more supports so as to place the shear web above the shear web mould in a substantially horizontal position; performing a method according to any one of claims 11-15; attaching an assembly fixture to the shear web in the substantially vertical position; releasing the plurality of lifting devices from the shear web so as to transfer support of the shear web from the plurality of lifting devices to the assembly fixture; and lowering the assembly fixture with the shear web so that a mounting flange of the shear web is placed on a structural member, such as a spar cap, in a wind turbine blade mould which is separate from the shear web mould.

Description

LIFTING DEVICE FOR TURNING A SHEAR WEB OF A WIND TURBINE BLADE TECHNICAL FIELD The present disclosure relates to a lifting device and a method of using a lifting device for turning a shear web upright. BACKGROUND Wind power provides a clean and environmentally friendly source of energy. Wind turbines usually comprise a tower, generator, gearbox, nacelle, and one or more rotor blades. The wind turbine blades capture kinetic energy of wind using known airfoil principles. Modern wind turbines may have rotor blades that exceed 90 meters in length. Wind turbine blades are usually manufactured by forming two shell parts or shell halves from layers of woven fabric or fibre and resin. Wind turbine blades of fibre-reinforced polymer are usually manufactured in moulds, where the pressure side and the suction side of the blade are manufactured separately by arranging glass fibre mats and/or other fibre-reinforcement material, such as carbon fibre, in each of the two mould parts. The two shell halves are usually glued together, wherein an adhesive is applied to the inner face of the lower blade half before the upper blade half is lowered thereon. Modern wind turbine blades are typically relatively thick at the root end and thin out towards to the tip. The same applies to the shear webs. Furthermore, modern wind turbine blades often extend along a curved course to position the tip of the unloaded blade further away from the tower than the root of the blade. Such a blade is commonly known as a pre-bent blade. Consequently, the shear webs also extend from a relatively thick root portion to a relatively thin tip portion along a curved course. Spar caps or main laminates are placed or integrated in the shell halves and may be combined with shear webs or spar beams to form structural support members. Spar caps or main laminates may be joined to, or integrated within, the inside of the suction and pressure halves of the shell. The shear webs are typically pre-moulded in a separate mould before being lifted therefrom, turned upright, and moved above the blade mould. Thus, the shear webs are typically bonded to the inside surface of the lower blade half prior to adhering the upper blade half, usually by means of upper and lower mounting flanges forming opposing edges of the shear web, arranged perpendicular to the web body. An adhesive such as epoxy is applied along these mounting flanges for bonding the shear webs to the respective inner surface of the shell half. However, this manufacturing approach presents significant challenges, particularly in lifting and turning the shear web. The shear web, which is relatively flexible along its chordwise direction, requires specialized lifting equipment to handle it. Without proper support along a significant portion of its length, the shear web tends to bend when lifted from lying flat on its mould. Subsequently, the shear web needs to be placed on specialized turning equipment, often necessitating the removal of the lifting equipment. Turning the shear web upright often leads to distortion and twisting, posing a safety hazard to nearby operators and risking damage to the web. Once the shear web is successfully turned, an assembly fixture is attached to transfer it to the blade mould. Furthermore, if a wind turbine blade has multiple shear webs with different shapes, specialized equipment is necessary for each shear web, as each may require a clockwise or counterclockwise turning operation. This increases the complexity and cost of blade manufacturing, as well as the cycle time. Moreover, the operators may be exposed to hazardous or uncomfortable postures, which can lead to safety concerns. SUMMARY On this background, it may be seen as an object of the present disclosure to provide a lifting device for releasably engaging a shear web for a wind turbine blade to allow turning the shear web from a substantially horizontal position to a substantially vertical position about the centre of gravity of the shear web. Another object of the present disclosure is to provide a method of turning a shear web from a substantially horizontal position to a substantially vertical position about the centre of gravity of the shear web. One or more of these objects may be met by aspects of the present disclosure as described in the following. A first aspect of this disclosure relates to a lifting device for releasably engaging a shear web for a wind turbine blade to allow turning the shear web from a substantially horizontal position to a substantially vertical position about a longitudinal axis of the shear web extending substantially through the centre of gravity of the shear web, the shear web having a first mounting flange, an opposing second mounting flange, and a web body arranged between the first mounting flange and the second mounting flange, the lifting device comprising: - a first attachment point for securing a line thereto; - preferably a second attachment point for securing a line thereto