Mobile bending device

Abstract

 A mobile bending device for bending a cable is provided, comprising
- at least two support elements (112, 113) fastened to at least one side frame (110, 111), wherein the at least two support elements (112, 113)
- are arranged with a spacing (132) between at least two of the support elements (112, 113),
- are designed for supporting a cable (150) and guiding the cable (150) through the bending device (100),

- at least one bending element (114) communicating with a bending control means (120), wherein the at least one bending element (114) and the bending control means (120)
- are fastened to the at least one side frame (110, 111),
- are designed for moving the at least one bending element (114) towards the spacing (132) thereby establishing a controlled pretension at the cable (150) and vice versa,

- driving means (140,...,143) communicating with at least one of the at least two support elements (112, 113) and/or with the at least one bending element (114), the driving means (140,...,143) is designed for moving the bending device (100) along the cable (150).
Further, a method for bending a cable is suggested.

Description

[0001] The invention relates to a mobile bending device for bending a cable and a method for bending a cable.

[0002] A wind turbine includes a tower to which a machine nacelle is mounted at its top end. A hub bearing rotor blades is mounted to a lateral end of the nacelle.

[0003] One element being essential for delivering energy generated by one or several wind turbines is cable. Wind turbines (i.e. nacelle, tower and a base) comprise a variety of cables, including, e.g., power transmission and distribution as well as control and communication cables.

[0004] An exemplary basic composition of a turbine comprises cables used within the nacelle which connect to a tower cable. A top section of the tower cable (being also referred to as "loop cable") is free hanging and has to loop around inside the nacelle as turns into the wind. The power generated in the nacelle is transported via the loop cable down towards a distribution point at the lower section of the tower.

[0005] Different types of cable maybe used for the transport of generated energy within a wind turbine like, e.g., low voltage (LV) and medium voltage (MV) power cables, dependent on a respective type of generator as well as on its design and location of a transformer part of the generator. The transformer may be part of the nacelle or may be installed at the middle/bottom of the tower or outside the tower.

[0006] When the transformer is located within the nacelle, a medium voltage (MV) power cable rated at 36 kV is used to connect the cable from the transformer to the distribution point at the base of the tower.

[0007] In contrast, when the transformer is located at the middle/bottom of the tower, a low voltage (LV) power cable is used to connect the LV generator in the nacelle to the transformer. Sometimes both, i.e. LV and MV power cables are installed as loop cables between the nacelle and the tower.

[0008] Following a current trend in the market with the need for wind turbines to deliver more power and thus operating at higher voltages, an increasing number of wind turbines will be installed having the transformer located in the nacelle.

[0009] As a consequence, the dimension of the power cables (like, e.g., the profile) to be installed within the wind turbines is increasing which will make the cables difficult to be handled.

[0010] As a further consequence, increasing effort (with regard to workload and finance) is necessary to achieve an appropriate installation of the cable. As an example, fixed cranes or moveable hoisting means are actually used for a proper handling of power cable within the wind turbine.

[0011] The object is thus to overcome such disadvantages and in particular to provide an improved approach for handling cables.

[0012] This problem is solved according to the features of the independent claims. Further embodiments result from the depending claims.

[0013] In order to overcome this problem, a mobile bending device is provided for bending a cable, comprising

• at least two support elements fastened to at least one side frame, wherein the at least two support elements
  • are arranged with a spacing between at least two of the support elements,
  • are designed for supporting a cable and guiding the cable through the bending device,
• at least one bending element communicating with a bending control means, wherein the at least one bending element and the bending control means
  • are fastened to the at least one side frame,
  • are designed for moving the at least one bending element towards the spacing thereby establishing a controlled pretension at the cable and vice versa,
• driving means communicating with at least one of the at least two support elements and/or with the at least one bending element, the driving means is designed for moving the bending device along the cable.

[0014] By applying the proposed solution, a cable, in particular a cable having a big size or huge dimension like, e.g., a power cable to be in installed in a wind turbine or connecting several wind turbines to a grid, can be handled in a favorable way, i.e. bended in a manner without unnecessary additional tools like, e.g., cranes or manpower.

[0015] As an advantage, big-sized cables can be bent with high precision. Thereby, almost all sizes or dimensions of cable (like, e.g., from 95 mm² to 2500 mm²) maybe be processed resulting in a quicker and easier installation of big-sized power cables, used e.g., in offshore and onshore applications.

[0016] As a further benefit, possible embodiments of the suggested bending device are small and light of weight and thus may be applied as a mobile device within very small operation or installation areas.

[0017] Each kind of cable like, e.g., armored or shielded cable or core of cables may be bent according to the proposed solution. Further, each element or object with similar characteristics of a cable like, e.g., a conductor or each kind of wire maybe treated by the suggested bending device.

[0018] Also a tube being made up of material (like, e.g., iron or copper) suitable to be bended may be handled by the suggested device.

[0019] The at least one bending element and the bending control means may be removable fastened to the at least one side frame.

[0020] In an embodiment, the driving means comprises at least one motor driving the at least one of the at least two support elements and/or the at least one bending element. By using a motor, big sized cables can be handled in a more easy way.

[0021] In another embodiment, the driving means comprises at least one gear box communicating with the at least one motor and the at least one of the at least two support elements and/or the at least one bending element.

[0022] In a further embodiment, the motor is an electric motor.

[0023] In a next embodiment, the at least two support elements and/or the at least one bending element is a roller element respectively.

[0024] It is also an embodiment that the roller element is a wheel.

[0025] Pursuant to another embodiment, the bending control means comprises at least one motor designed for moving the at least one bending element towards the spacing and vice versa.

[0026] In a further embodiment, the at least one bending element and/or the bending control means are removable fastened to the at least one side frame. This enables, e.g., a proper placement of a cable or conductor within the bending device, in particular at the support elements.

[0027] The problem stated above is also solved by a method for bending a cable comprising the following steps:

• fixing a device as described herein at the cable such that the cable is supported by the at least two support elements,
• moving the at least one bending element towards the spacing with the help of the bending control means thereby establishing a controlled pretension at the cable,
• activating the driving means for moving the bending device via a predetermined distance along the cable thereby forming the cable with a defined bending,
• removing the device from the cable.

[0028] Embodiments of the invention are shown and illustrated in the following figures:

Fig.1

shows a perspective schematic view of an exemplary embodiment of a bending device according to the proposed solution;

Fig.2

shows a side view of the bending device of Fig.1;

Fig.3

shows in a schematic side view an exemplary scenario using the bending device as illustrated in Fig.1 and Fig.2;

Fig.4

illustrates a further exemplary scenario including an end-section of a power cable;

Fig.5

illustrates in a schematic view an exemplary sequence of the suggested bending procedure based on the scenario of Fig.4;

Fig.6

shows the result after finalization of the suggested bending procedure.

[0029] Fig.1 shows a perspective schematic view of an exemplary embodiment of a mobile bending device 100 according to the proposed solution. Thereby, the bending device 100 comprises a side frame 110 at a front side and a side frame 111 at a backside.

[0030] Fig.2 shows a side view of the bending device 100 of Fig.1 without the side frame 110 to enable better visibility of the buildup of the bending device 100.

[0031] In the following, a possible structure of the bending device 100 will be explained in more detail by referring to Fig.1 and Fig.2 in parallel.

[0032] A support element 112 and a support element 113 are fastened to the two side frames 110, 111. In this example, each of the support elements 112, 113 is represented by a wheel (also referred as "driving wheel") with a rotation axis 130. The driving wheels 112, 113 are adjusted along an axis 131 (indicted by a dotted line) at a bottom part of the bending device 100, with a spacing 132 between the rotations axis 130 of the driving wheels 112, 113.

[0033] Further, a bending element 114 represented, e.g., by a bending wheel with a rotation axis 134 is movable fastened to both side frames 110, 111. The bending wheel 114 is arranged at a top part of the bending device 100 with an adjustable spacing 133 between the rotation axis 134 of the bending wheel 114 and the axis 131. For adjustment of the spacing 133, i.e. modifying the distance between the rotation axis 134 and the axis 131, the bending wheel 114 is communicating with a bending control means 120 located on top of the bending device 100. The bending control means 120 may be represented by a screw-able bending control handle. Dependent on the direction of the screwing (clockwise or counterclockwise) the bending wheel 114 is navigated, i.e. moved towards the spacing 132 between the two driving wheels 112, 113 and vice versa (indicated by an arrow 135).

[0034] Each of the driving wheels 112, 113 may be driven by a motor 140, 141. Thereby, the motor 140 is communicating with the driving wheel 112 via a gearbox 142 and the motor 141 is communicating with the driving wheel 143 via a gearbox 143.

[0035] Alternatively, only one of the driving wheels 112, 113 may be driven by a motor. As a further alternative, both driving wheels 112, 113 may be driven by only one motor.

[0036] The motor 140, 141 may be an electric motor.

[0037] According to an advanced embodiment (not shown), instead of using the screw-able bending control handle, the bending control means 120 may comprise a further motor like, e.g., an electric motor, navigating the bending wheel 114 back and forth towards the spacing 132 and vice versa.

[0038] Fig.3 shows in a schematic side view an exemplary scenario using the bending device 100 as illustrated in Fig.1 and Fig.2 for bending a cable which may be, e.g., a core of a cable or a conductor. It should be noted, that in Fig.3 the bending device 100 is shown without the side frame 110 at the front side to enable a better view on the scenario inside both side frames 110, 111.

[0039] According to Fig.3 a cable 150 is guided through the bending device 100 thereby being supported by the two driving wheels 112, 113. According to the proposed solution, the shape of the support elements, i.e. the driving wheels 112, 113 as well as the shape of the bending element 114, i.e. the bending wheel is adapted to the characteristics and/or the form of the cable 150. As can be seen in Fig.1, each of the wheels 112, 113, 114 has a cylindrical shape with an increasing radius towards both ends of the wheels resulting in a stable support or placement of the cable 150.

[0040] In this scenario, the movement of the bending wheel 114 may be controlled by the bending control handle 120 in a way navigating the bending wheel 114 towards the spacing 132 between both wheels 112, 113 (indicated by an arrow 151), thereby pressing the cable 150 towards the driving wheels 112, 113 and thus establishing a pretension on the cable 150.

[0041] According to the proposed solution, both electric motors 140, 141 may be activated in a way driving the driving wheels 112, 113 counterclockwise (indicated by an arrow 153), thereby moving the bending device 100 along the cable 150 with a defined length towards a direction 152 to achieve the intended bending in the cable 150.

[0042] The power of the electric motors 140, 141 as well as the characteristics of the gearboxes 142, 143 and the surface of the driving wheels 112, 113 should be adapted to the characteristics of the cable 150 to ensure optimized grip between the driving wheels 112, 113 and the cable 150 and thus to achieve optimized forcing of the bending device 100 along the cable 150.

[0043] Based on the established pretension on the cable 150 the driving or movement of the bending device 100 along the cable 150 towards the direction 152 results in a controlled bending of the cable 150 defined by a bending-direction (indicated by an arrow 155) and a bending-radius (indicated by an arrow 154). Usually, the bending-direction 155 points towards the bending wheel 114 in consequence to the established pretension on the cable 150. Thus, the bending device 100 has to be adjusted accordingly, i.e. the bending device 100 has to be mounted or fixed at the cable 150 in a way forcing the bending wheel 114 against the cable 150 along a defined direction and with a controlled pressure to receive the intended bending-direction 155 and bending-radius 154.

[0044] In the following, a bending procedure applying the suggested bending device based on a further exemplary scenario is explained in more detail.

[0045] Fig.4 illustrates a further exemplary scenario including an end-section 410 of a power cable 400 which may be implemented in a tower of a wind turbine. According to Fig.4, an armoring 420 has been taken off within the end-section 410, thus three conductors 430, 431, 432 are ready for bending to enable, e.g., a correct positioning within a cable termination at a distribution point within the tower.

[0046] Fig.5 illustrates in a schematic view an exemplary sequence of the suggested bending procedure based on the scenario of Fig.4. As an example, each of the three conductors 430, 431, 423 of Fig.4 should receive a first bending clockwise with a bending radius of 90° within a first part 550 of the section 410 and a second bending counterclockwise with a bending radius of 90° at a third part 552 of the section 410. Within a second part 551 of the section 410 the three conductors 430, 431, 432 should not receive any bending.

[0047] In a first step, a bending device as suggested in Fig.1 and Fig.2 has to be fixed at the first conductor 430. For that purpose, the bending wheel 114 together with the bending control handle 120 are disassembled from the bending device 100 to enable proper placement of the first conductor 430 at the two driving wheels 112, 113 supporting the first conductor 430. For implementing the first bending the bending device 100 is sited at the beginning of the first part 550 thereby being adjusted towards the correct position as indicated by an arrow 520 to achieve the intended first bending.

[0048] After correct positioning and adjustment of the bending device 100, the bending wheel 114 together with the bending control handle 120 are reassembled with the bending device 100.

[0049] In a next step, by appropriate controlling of the bending control handle 120, the bending wheel 114 is moved towards the first conductor 430 along a direction 511 until the necessary pretension between the bending wheel 114 and the first conductor 430 has been reached.

[0050] In a following step, the two electric motors 140, 141 are activated driving the driving wheels 112, 113 via the gearboxes 142, 143 thereby moving the bending device 100 along the first part 550 of the first conductor 430 resulting in the intended first bending of the conductor 430 with the intended bending-direction 155 and bending-radius 154.

[0051] After implementation of the first bending, the electric motors 140, 141 are stopped and the bending device removed from the first conductor 430.

[0052] In a next step, initiating the second bending at the third part 552 of the first conductor 430, the bending device 100 is fixed again at the beginning of the third part 552 of the first conductor 430 in a way as already explained with regard to the first bending. As illustrated in Fig.5, the bending device 100 is sited at the beginning of the third part 550 thereby being adjusted towards the correct position as indicated by an arrow 521 to achieve the intended second bending.

[0053] After adjustment, the bending wheel 114 is moved again towards the first conductor 430 along a direction 512 which is now opposite to the direction 511 forcing the first bending. After establishing the necessary pretension at the first conductor 430, the electric motors 140, 141 are activated again, thereby moving the bending device 100 along the third part 552 of the first conductor 430 resulting in the intended second bending of the first conductor 430 with the intended bending-direction 155 and bending-radius 154.

[0054] After implementation of the second bending, the bending device 100 is removed from the first conductor 430.

[0055] The aforementioned steps are repeated for the second and third conductor 431, 432 to get the same bendings implemented.

[0056] Fig.6 shows the result after finalization of the suggested bending procedure.

[0057] Although the invention is described in detail by the embodiments above, it is noted that the invention is not at all limited to such embodiments. In particular, alternatives can be derived by a person skilled in the art from the exemplary embodiments and the illustrations without exceeding the scope of this invention.

Claims

1. Mobile bending device (100) for bending a cable, comprising

- at least two support elements (112, 113) fastened to at least one side frame (110, 111), wherein the at least two support elements (112, 113)

- are arranged with a spacing (132) between at least two of the support elements (112, 113),

- are designed for supporting a cable (150) and guiding the cable (150) through the bending device (100),

- at least one bending element (114) communicating with a bending control means (120), wherein the at least one bending element (114) and the bending control means (120)

- are fastened to the at least one side frame (110, 111),

- are designed for moving the at least one bending element (114) towards the spacing (132) thereby establishing a controlled pretension at the cable (150) and vice versa,

- driving means (140,...,143) communicating with at least one of the at least two support elements (112, 113) and/or with the at least one bending element (114), the driving means (140,...,143) is designed for moving the bending device (100) along the cable (150).

2. The mobile bending device according to claim 1, wherein the driving means (140,...,143) comprises at least one motor (140, 141) driving the at least one of the at least two support elements (112, 113) and/or the at least one bending element (114).

3. The mobile bending device according to claim 2, wherein the driving means (140,...,143) comprises at least one gear box (142, 143) communicating with the at least one motor (140, 141) and the at least one of the at least two support elements (112, 113) and/or the at least one bending element (114).

4. The mobile bending device according to claim 2 or 3,
wherein
the motor (140, 141) is an electric motor.

5. The mobile bending device according to any of the preceding claims, wherein
the at least two support elements (112, 113) and/or the at least one bending element (114) is a roller element respectively.

6. The mobile bending device according to claim 5, wherein the roller element is a wheel.

7. The mobile bending device according to any of the preceding claims, wherein
the bending control means (120) comprises at least one motor designed for moving the at least one bending element (114) towards the spacing (132) and vice versa.

8. The mobile bending device according to any of the preceding claims, wherein
the at least one bending element (114) and/or the bending control means (120) are removable fastened to the at least one side frame (110, 111).

9. A method for bending a cable comprising the following steps:

- fixing a device (100) according to any of the preceding claims at the cable (150) such that the cable (150) is supported by the at least two support elements (112, 113),

- moving the at least one bending element (114) towards the spacing (132) with the help of the bending control means (120) thereby establishing a controlled pretension at the cable (150),

- activating the driving means (140,...,143) for moving the bending device (100) via a predetermined distance along the cable thereby forming the cable with a defined bending,

- removing the device (100) from the cable (150).

Drawing