APPARATUS AND METHOD FOR AUTOMATION OF WELD SEAMS MACHINING

Abstract

An apparatus for automation of weld seams machining of a wind turbine tower is provided. The apparatus includes an automated arm; a machining tool fixed to the automated arm; a compensator system fixed to the machining tool or being part of the automated arm; a joint visor that identifies and locates the weld seam; and a control unit to coordinate the movement of the machining tool with the compensator system and the joint visor. A method of performing a welded circular seam machining in a wind turbine tower with the apparatus is also provided.

Claims

1. An apparatus for automation of weld seams machining of adjacent shells of a wind turbine tower, the apparatus comprising: an automated arm; a machining tool joined to the automated arm; a compensator system fixed to the machining tool or being part of the automated arm; a joint visor that identifies and locates a weld seam to be machined detecting an exact location, measure and form; and a control unit to coordinate a movement of the machining tool with the compensator system and the joint visor such that the joint visor detects the exact location, measure and form of the weld seam and the compensator system displaces the machining tool to the exact location of the weld seam and adapts a position of the machining tool to a measure and a form of the weld seam.

2. The apparatus for automation of weld seams machining according to claim 1, further comprising rails configured to be installed in a surface disposed parallel to a longitudinal direction of the wind turbine tower, the weld seam of which is to be machined; and the automated arm comprises first guides in order to displace on the rails.

3. The apparatus for automation of weld seams machining according to claim 1, further comprising wheels configured to allow a displacement of the automated arm with respect to the adjacent shells and the weld seam to be machined.

4. The apparatus for automation of weld seams machining according to claim 1, further comprising a GPS system connected to the control unit to determine the position of the automated arm and displace the automated arm along the longitudinal direction of the wind turbine tower and the weld seam to be machined.

5. The apparatus for automation of weld seams machining according to claim 1, further comprising: a beam configured to be introduced through an interior of the wind turbine tower; the automated arm comprises second guides in order to displace on the beam.

6. The apparatus for automation of weld seams machining according to claim 5, wherein the beam comprises a plurality of pieces, joined among them and which are made of a rigid material in order to outstand at least a weight of the automated arm, the machining tool, the compensator system and the joint visor.

7. The apparatus for automation of weld seam machining according to claim 1, wherein the machining tool fixed to the automated arm is a grinding wheel or an abrasive wheel.

8. The apparatus for automation of weld seam machining according to claim 1, wherein the compensator system comprises a processor that receives information from the control unit, according to data obtained by the joint visor, and displaces the machining tool so as to exert a same pressure, during a machining operation, along the weld seam, according to a geometry of the weld seam.

9. A method of performing a welded circular seam machining in a wind turbine tower with the apparatus of claim 1, the method comprising: placing the apparatus near one weld seam; activating the joint visor to capture images of the weld seam; processing the data captioned by the joint visor in the control unit; adapting the position of the automated arm and the machining tool according to the data of the weld seam captioned by the joint visor; machining the weld seam by continuously adapting the position of the machining tool with the data captioned by the joint visor, by means of the compensator system, to assure that the same pressure is made by the machining tool along the weld seam.

Description

BRIEF DESCRIPTION

[0027] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

[0028] FIG. 1 shows an apparatus for automation for weld seams machining of adjacent shells of a wind turbine tower, in accordance with embodiments of the present invention; and

[0029] FIG. 2 shows two apparatus for automation for weld seams machining of adjacent shells working on a machining on part of a wind turbine tower, in accordance with embodiments of the present invention.

DETAILED DESCRIPTION

[0030] According to FIGS. 1 and 2, an exemplary embodiment of the invention is disclosed.

[0031] An apparatus (1) for automation for weld seams (6) machining of adjacent shells of a wind turbine tower (7) is described. The apparatus comprises an automated arm (2) and a machining tool (3) joined to the automated arm (2). Furthermore, the apparatus (1) comprises a compensator system (4) and a joint visor (5) which are essential in order to solve the technical problems of the state of the art and guarantee that the machining tool (3) exerts the same pressure during the whole machining operation. The joint visor (5) identifies and locates the weld seam (6) to be machined detecting the exact location, measure and form of the weld seam (6).

[0032] The compensator system (4) is fixed to the machining tool (3) or is part of the automated arm (2). The joint visor identifies and locates the weld seam and the joint to be welded. The elements of the apparatus (1) (the automated arm (2), the machining tool (3), the compensator system (4) and the joint visor (5)) are controlled together via a control unit which is part of the apparatus (1) and that is configured to coordinate the movements of the machining tool (3), connected to the compensator system (4) and to the articulated arm (2), with the data received from the joint visor (5).

[0033] The control unit coordinates the movement of the machining tool (3) with the compensator system (4) and the joint visor (5) such that the joint visor (5) detects the exact location, measure and form of the weld seam (6) and the compensator system (4) displaces the machining tool (3) to the exact location of the weld seam (6) and adapts the position of the machining tool (3) to the measure and form of the weld seam (6).

[0034] More specifically, the control unit is configured to coordinate the movement of the machining tool (3) with the compensator system (4) and the joint visor (5) such that the joint visor (5) detects the exact location, measure and form of the weld seam (6) and the compensator system (4) displaces the machining tool (3) to the exact location of the weld seam (6) and adapts the position of the machining tool (3) to the measure and form of the weld seam (6).

[0035] The machining tool (3) joined to the automated arm (2) is, in an embodiment of the invention, a grinding wheel or an abrasive wheel. In another embodiment the machining tool (3) can be any steel removal tool.

[0036] The compensator system (4) preferably comprises a processor that receives information from the control unit, according to the data obtained by the joint visor (5) (which can be part of an artificial visor system). The processor, based on the data, displaces the machining tool (3) so as to exert the same pressure, during the machining operation, along the weld seam (6), according to the geometry of the weld seam (6).

[0037] The weld bear is not a perfect circle. This is due to the forces of gravity and typical manufacturing imperfections such as misalignments or small buns. Those imperfections make the cord at the time of being machined to have different measures and positions which vary from a perfect circle. The compensating system (4) ensures that the machining tool (3) always exerts the same machining force even though the welding bead is irregular.

[0038] The machining tool (3) has to provide always the same pressure as otherwise, it is possible to machine over or under the required pressure conditions, thus affecting the quality and validity of the welding process. In the cases in which the machining tool (3) provides a pressure under the one required in the process; it can leave a not valid weld seam (6) thickness. In this case the section of the welded section would not be accepted and would have to be redone. If it the machining tool (3) provides a pressure over the one required in the process, the fatigue strength would be too low.

[0039] The compensator system (4) allows adapting the pressure of the machining tool (3) to the required pressure according to the data received from the joint visor (5). Thus, the compensator system (4) is essential in the apparatus (1) of embodiments of the present invention, allowing to recognize the geometry of the weld seam (6) and to compensate the pressure.

[0040] The joint visor (5) is another essential element of the apparatus (1) of embodiments of the present invention. This element is in charge of recognizing the geometry of the weld seam cord and then sending this information to the control unit, so the control unit sends the correct orders to the compensator system (4) in order to correctly position the machining tool (3). The combination of the joint visor (5) and the compensator system (4) assures that the optimum machining is achieved, both in time and in quality.

[0041] In another embodiment of the invention, the apparatus (1) further comprises rails (8) configured to be installed in a surface (9) disposed parallel to the longitudinal direction of a wind turbine tower (7) the circumferential weld seam (6) of which is to be machined. In this embodiment, the automated arm (2) comprises first guides (10) in order to displace on the rails (8).

[0042] In another embodiment, the apparatus (1) comprises wheels configured to allow the displacement of the automated arm (2) with respect to the shells and the weld seams (6) to be machined.

[0043] In a further embodiment, the apparatus comprises a GPS system connected to the control unit to determine the position of the automated arm (2) and displace the automated arm (2) along the longitudinal direction of the tower (7) and the weld seams (6) to be machined.

[0044] Since the DC requirements include welds on the two sides of the joint, in this case, the joint between two shells of the wind turbine tower has to be made on the exterior side and also on the interior of the tower (7). To allow the machining of the welding in the interior, the apparatus (1) can comprise a beam configured to be introduced through the interior of adjacent shells. In this embodiment, the automated arm (2) comprises second guides in order to displace on the beam. Preferably, the beam comprises a plurality of pieces, joined between them and which are made of a rigid material in order to outstand the weight of the apparatus (2) or at least the weight of the automated arm (2), the machining tool (3), the compensator system (4) and the joint visor (5).

[0045] The beam is a guiding rack system to allow the displacement of the arm thorough the interior of the wind turbine tower (7). The beam has to be rigid enough to support the weight of the automated arm (2) so the automated arm (2) works without excessive vibrations. Also, the beam has to be configured as simple as possible to facilitate its assembly. The assembly inside the section is preferably made in two or more parts. Preferably those parts are introduced by means of a bridge crane in the interior of the section of the wind turbine tower (7). The parts may be screwed.

[0046] Preferably, the apparatus (1) to be used in the interior of the section of the tower (7) is smaller than the apparatus to be used for machining the exterior of the tower (7). Specifically, the automated arm (2) is smaller in this first case because it has to fit in the interior of the section (7) which can have a diameter from 4 m to 6 m.

[0047] It is also a part of embodiments of the invention a method of performing a weld circumferential seam (6) machining in a wind turbine tower (7) with the apparatus (1) previously described.

[0048] The method comprises the following steps: [0049] placing the apparatus (1) near one weld seam (6); [0050] activating the joint visor (5) to capture images of the weld seam (6); [0051] processing the data captioned by the joint visor (5) in the control unit; [0052] adapting the position of the automated arm (2) and the machining tool (3) according to the data of the weld seam (6) captioned by the joint visor (5); [0053] machining the weld seam (6) by continuously adapting the position of the machining tool (3) with the data captioned by the joint visor (5), by means of the compensator system (4), to assure that the same pressure is made by the machining tool (3) along the weld seam (6).

[0054] Prior to the machining of the weld seams (6) with the apparatus (1) of embodiments of the invention, the shells forming the wind turbine tower (7) are placed adjacent to each other and the joints among them are formed. Preferably all the joints forming the wind turbine tower (7) are welded before the operations of machining star.

[0055] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0056] For the sake of clarity, it is to be understood that the use of a or an throughout this application does not exclude a plurality, and comprising does not exclude other steps or elements.