Rotor blade inspection rig

Abstract

Disclosed is a rotor blade inspection device having a maintenance chamber through which a rotor blade can pass vertically, wherein the floor opening and a roof opening, through which the rotor blade can pass, are arranged in the chamber floor and in the chamber roof of the maintenance chamber, characterized in that the maintenance chamber is arranged on a supporting frame, and in that the bracing frame can be supported on a tower of a wind turbine, and in that the chamber floor and the chamber roof of the maintenance chamber are respectively designed as a diaphragm system in order to minimize a gap between the floor opening or roof opening and the rotor blade.

Claims

1. A rotor-blade inspection rig, comprising: a bracing frame configured for support on a tower of a wind turbine; a carrying frame connected to the bracing frame such as to allow movement of the bracing frame in relation to the carrying frame; and a maintenance chamber arranged on the carrying frame and configured for passage of a rotor blade in a vertical direction, said maintenance chamber including a chamber floor with a floor opening and a chamber roof with a roof opening to allow passage of the rotor blade, the chamber floor and the chamber roof each configured as a diaphragm system to minimize a gap between the floor opening or the roof opening and the rotor blade, said maintenance chamber rotatable in a horizontal plane wherein a rotation axis of the maintenance chamber coincides with an axis of the rotor blade and a twist in the rotor blade such that the maintenance chamber is turned relative to the fixed carrying frame.

2. The rotor-blade inspection rig of claim 1, wherein the bracing frame is constructed so as to be displaceable in the horizontal direction relative to the carrying frame, and guided telescopically.

3. The rotor-blade inspection rig of claim 2, wherein the maintenance chamber is suspended on the carrying frame.

4. The rotor-blade inspection rig of claim 1, wherein the maintenance chamber is composed of a structural frame and cladding elements for the lateral faces of the maintenance chamber, to form a working space that is largely closed off outwardly.

5. The rotor-blade inspection rig of claim 1, wherein a volume of the maintenance chamber is configured to be enlarged by means of at least one lateral element that is moved telescopically.

6. The rotor-blade inspection rig as claimed in claim 5, further comprising two lateral elements configured for displacement relative to the maintenance chamber and positioned at right angles to the rotor-blade sides, and lockable with respect to the maintenance chamber.

7. The rotor-blade inspection rig of claim 1, wherein the diaphragm system is composed of a solid roof element or a solid floor element and of one, two or more movable diaphragm elements.

8. The rotor-blade inspection rig as claimed in claim 7, wherein the diaphragm elements are realized such that they move translatory or rotationally or is pivoted.

9. The rotor-blade inspection rig of claim 8, wherein the diaphragm system is realized as a ring diaphragm.

10. The rotor-blade inspection rig of claim 7, wherein the diaphragm system is configured to be rotatable in the horizontal plane.

11. The rotor-blade inspection rig of claim 7, wherein the diaphragm elements of the diaphragm system have a seal toward an outer edge of the rotor-blade.

12. The rotor-blade inspection rig of claim 1, further comprising a tilt compensation system having cable feedthrough winches, said tilt compensation system drives the rotor-blade inspection rig in the vertical direction, wherein the cable feedthrough winches are mounted so as to be horizontally displaceable by which the tilt of the rotor-blade inspection rig is adjusted.

13. The rotor-blade inspection rig of claim 1, wherein the maintenance chamber is provided with a roof access in the roof of the maintenance chamber.

14. The rotor-blade inspection rig of claim 1, wherein the maintenance chamber is provided with a feed roller for additionally or solely guiding the maintenance chamber on the rotor blade in the region of a blade root.

Description

(1) Further details, features and advantages of designs of the invention are given by the following description of exemplary embodiments, with reference to the associated drawings. There are shown:

PREFERRED EMBODIMENTS

(2) FIG. 1: rotor-blade inspection rig, perspective representation,

(3) FIG. 2: rotor-blade inspection rig, in side view,

(4) FIG. 3: rotor-blade inspection rig, in front view,

(5) FIG. 4a: rotor-blade inspection rig, in side view,

(6) FIG. 4b: rotor-blade inspection rig, in top view,

(7) FIG. 4c: rotor-blade inspection rig, in top view with rotated chamber,

(8) FIG. 5a: rotor-blade inspection rig with rotor blade in side view, with support on tower,

(9) FIG. 5b: rotor-blade inspection rig with rotor blade in side view, with support on rotor blade,

(10) FIG. 6a, b: seal system with brushes and inflatable seals,

(11) FIG. 7a: diaphragm system with fully closed diaphragms, and

(12) FIG. 7b: diaphragm system with opened diaphragms.

(13) A rotor-blade inspection rig 1 is shown in various views in FIGS. 1 to 3.

(14) FIG. 1 shows a perspective representation of the rotor-blade inspection rig 1, which is composed substantially of a maintenance chamber 2, which is suspended on a carrying frame 3. The carrying frame 3 is connected to the bracing frame 4, which is guided therein. The bracing frame 4 leans against the tower 5, not represented here, of the wind turbine.

(15) Structurally, the represented rotor-blade inspection rig 1 is composed of an upper carrying frame 3, which is formed from two longitudinal beams that run parallel to the lateral faces of the rotor blade, and from steel, aluminum or fiber composite material. The beams are each structurally connected to each other by lateral braces. Fastened to the upper carrying frame 3 are cable feedthrough winches 6 or other winches, which drive the maintenance system in the vertical direction. The cable feedthrough winches 6 are mounted on the carrying frame 3 so as to be displaceable horizontally by means of the tilt compensation system 7, whereby the tilt of the maintenance system can be adjusted. Integrated into the carrying frame 3 is the bracing frame 4, which supports the maintenance system relative to the tower 5 of the wind turbine. The bracing frame 4 is displaceable in the horizontal direction relative to the rotor-blade inspection rig 1.

(16) A maintenance chamber 2 is mounted on the upper carrying frame 3 such that it can turn relative to the carrying frame 3. The maintenance chamber 2 is preferably composed of a closed structure, which provides protection, against rain wind and cold, to the engineers working therein.

(17) The maintenance chamber 2 is supported in the horizontal direction on the upper carrying frame 3, such that the upper carrying frame 3, the maintenance chamber 2 and the feed roller 10, arranged on the chamber floor, form an overall structure that can be subjected to shear loading.

(18) In the vertical direction, the maintenance chamber 2 is supported on the upper carrying frame 3. The weight force of the maintenance chamber 2 is thus transferred to the upper carrying frame 3.

(19) In the horizontal direction, the following distinct load paths ensue. In the case of support on the tower 5 by means of the bracing frame 4, the horizontal loads are lead directly into the upper carrying frame 3. In the case of support on the rotor-blade front edge by means of the feed roller 10, the horizontal loads are transmitted, in the form of a shear load, through the maintenance chamber 2, into the upper carrying frame 3, which is connected in a form-fitting manner to the upper side of the maintenance chamber 2.

(20) The maintenance chamber 2 is preferably configured as described and represented in the following.

(21) The maintenance chamber 2 is preferably composed of a light cell, of a support structure of high-strength steel struts, of fiber-reinforced plastics or aluminum, the solid structural frame 14. The intermediate spaces of the support structure are sealed, on the front side of the chamber, by sealing elements such as, for example, light plastic tarpaulins. The sealing elements are preferably transparent.

(22) The maintenance chamber 2 preferably has a rectangular cross section, the long sides enclosing the rotor-blade sides and the short sides enclosing the rotor-blade edges, the front and rear edge of the rotor blade.

(23) The long sides are composed of separate elements, the lateral elements or balconies, which can be displaced, or extended, relative to the chamber cell, at right angles to the rotor-blade sides. In the extended position, they can be locked with respect to the maintenance chamber 2.

(24) The balconies 16 also are preferably composed of a light-construction support structure, for example of fiber-composite or aluminum sandwich elements.

(25) The lateral faces of the balconies 16 are preferably open, and may be sealed manually, for instance by a roller door, a shutter or a tarpaulin. The sealed elements of the balcony lateral faces are preferably transparent.

(26) The maintenance chamber 2 is preferably suspended on the upper carrying frame 3 by rollers or other guide elements. The guidance is configured such that the maintenance chamber 2 can move on a circular path about the twist axis of the rotor blade, relative to the carrying frame 3.

(27) The maintenance chamber 2 is such that, in principle, it is possible both to walk on the chamber floor and to walk on the chamber roof. Maintenance works can thus be performed on both levels. The chamber floor can be walked on because of a solid, walkable floor element, and the roof can be walked on because of a solid, walkable roof element and the roof access 19. The walkability of the roof allows, particularly in the region of the rotor-blade root, better access for maintenance works that frequently cannot be covered with the use of conventional rigs.

(28) The open sides of the maintenance chamber 2 to the outside, both floor and roof, are delimited by an outer railing 9. The regions in the maintenance chamber 2 toward the rotor blade 11 are secured by an inner railing 8. In order to reduce the height of the overall system, the upper railings are fastened in a foldable, telescoping or demountable manner to the chamber roof.

(29) The diaphragm system is an essential element of the rotor-blade inspection rig 1, in order to encompass and seal the outer contour of, for example, a rotor blade 11. The diaphragm system of the chamber base and chamber roof, in particular according to FIGS. 6a,b and 7a,b, is composed of a walkable, solid floor element or roof element 15 and of one or more movable, positionable and possibly also walkable diaphragm elements 13, which can be moved at right angles to the rotor-blade sides.

(30) The chamber floor and the chamber roof have a central cut-out, the floor opening, or roof opening 12, which corresponds to the contour of the largest possible blade cross sections of the anticipated rotor blades 11.

(31) The diaphragm elements 13 are mounted parallel to each other on planes that are offset in the vertical direction, and as a result can also be positioned in an overlapping manner.

(32) The diaphragm elements 13, in the maximally closed state, together with the solid floor element 15 or the solid roof element 15 of the fixed balcony 16, form a closed floor, the latter extending over a plurality of levels. In this state, large regions of the diaphragm elements 13 overlap, and these are moved maximally in the direction of the center of the chamber.

(33) When the positionable diaphragm elements 13 are in the maximally opened state, there is a resultant opening, the floor and ceiling opening 12, in the center of the chamber. The movable diaphragm elements 13 are contoured in the direction of the rotor blade 11 such that they can be moved very close to the respective rotor-blade surface, for differing blade types and cross-sectional sizes, and thus a minimal peripheral gap is obtained. An ideal gap dimension is obtained in this case by the rotation of the maintenance chamber 2 in combination with the positioning of the contoured diaphragm elements 13.

(34) In a special alternative embodiment of the maintenance system, the maintenance chamber 2 is fixed with respect to the carrying frame 3. Here, as an alternative to the aforementioned variant, the rotation is realized by means of the diaphragm system itself. The diaphragm elements 13 thus execute both a rotational and a translational motion.

(35) The described diaphragm system is also intended for open rotor-blade inspection rigs, the function of the sealing then being reduced to the fall protection.

(36) Particularly preferably, the positionable diaphragm elements 13 of the diaphragm system are dimensioned, mounted and guided in such a manner that they themselves can be walked on, such that simplification is achieved for particular works on the rotor blades.

(37) Possibilities for the fastening of occupants are provided both on the floor level and on the roof level of the maintenance chamber 2. The fastening of occupants is to be understood to mean the securing of persons or objects, which are connected, for example by means of a cable, to the maintenance chamber 2.

(38) The maintenance chamber 2 is equipped with a device that, during the maintenance operation, enables occupants to change over safely from the floor level to the roof level and vice versa. For this purpose, in the exemplary embodiment represented, a roof access 19 is provided, which can be used as a ladder out from the interior of the maintenance chamber 2 for changing over from the floor level to the roof level of the maintenance chamber 2.

(39) In a particular embodiment of the maintenance system, for the maintenance of rotor blades 11 having particularly large cross sections, the distance between the two longitudinal beams of the carrying frame 3 can be varied between the transport state and the maintenance state. Increasing this distance ensures that even rotor blades 11 having a profile width of more than 2.55 m can be inspected.

(40) The maintenance chamber 2 has a solid structural frame 14 having a maximum width of 2.55 m, in order to comply with legal regulations for simplified road transport. The lateral elements 16 of the maintenance chamber 2, also referred to as balcony elements, are extendable, and in the extended state increase the chamber volume.

(41) The method for inspecting rotor blades 11 for inspection and maintenance purposes by means of a rotor-blade inspection rig 1 of the described type is described in the following.

(42) The maintenance chamber 2 is driven, in the closed transport state, on a towed vehicle, to the wind turbine. On the ground, the lateral balconies 16 are extended and fixed in position. The railings of the roof level, which are not represented, are folded out. No further work for assembly of the maintenance chamber 2 is then required.

(43) According to a particular embodiment of the maintenance chamber 2, the balconies 16 are not fixed in place once, but are continuously positioned during the service operation.

(44) The maintenance chamber 2 travels, with a fully closed diaphragm system, and thus with a completely closed floor, to the rotor-blade tip, a continuous tilt compensation being effected manually or automatically.

(45) Before the rotor-blade tip, the positionable diaphragm elements 13 are opened completely.

(46) There follows a manual or automatic feed-in of the rotor-blade tip into the roof opening, if necessary assisted by the occupants of the maintenance chamber 2.

(47) In addition, the chamber is rotated manually or automatically, such that the chamber sides are oriented parallel to the rotor-blade sides.

(48) The maintenance chamber 2 is locked at the fed-in rotor blade 11 by advancing the diaphragm elements 13 until the support elements on the insides of the diaphragm have contact with the rotor blade 11.

(49) The advancing of the positionable diaphragm elements 13 is effected with force limitation or travel limitation, such that the rotor blade 11 does not incur any damage.

(50) For the purpose of advancing the maintenance chamber 2 along the rotor blade 11, the movable diaphragm elements 13 are opened fully or partially, or advanced by means of closed-loop and open-loop control means.

(51) FIG. 2 shows the rotor-blade inspection rig 1 according to FIG. 1 in side view. The roof access 19 is arranged in a rear corner of the maintenance chamber 2. The outer railing 9 securely delimits the maintenance chamber 2 for the persons present in the chamber, even if claddings of the lateral faces have not been fitted. The solid structural frame 14 forms the structural core of the maintenance chamber, on which the railings and cladding elements are fixed, or can be fixed if required. A longitudinal beam of the carrying frame 3 accommodates the longitudinal beam of the bracing frame 4 in a telescopic manner, and the latter is guided linearly in the carrying frame 3. The tilt compensation system 7 consists in the guiding and positioning of the cable feedthrough winches 6 along the longitudinal beam of the carrying frame 3, the tilt compensation system 7 additionally having means for driving and controlling the positioning.

(52) In FIG. 3, the rotor-blade inspection rig 1 of FIGS. 1 and 2 is represented in front view, in the radial direction out from the tower. The lateral elements 16 are in an extended position, and in this state the maintenance chamber 2 has an increased chamber volume, which improves the accessibility and freedom of movement for the service engineers. The positionable diaphragm elements 13 in the chamber roof and in the chamber floor are also in an extended position. Additionally represented in front view are the transverse braces of the structural frame 14 and of the carrying frame 3, and the feed roller 10, arranged transversely in relation to the maintenance chamber 2, in the floor region, is indicated in the drawing. The two cable feedthrough winches 6 are arranged so as to be positionable along the two longitudinal struts of the carrying frame 3, and the roof access 19 is extended with a lateral element 16. The extended lateral elements 16 form balcony-type enlargements of the maintenance chamber 2, and are therefore also referred to as balconies.

(53) The rotor-blade inspection rig 1 is represented in highly schematic form in FIGS. 4a, b and c.

(54) In FIG. 4a, the rotor-blade inspection rig 1 is shown in side view. The maintenance chamber 2 is suspended on the carrying frame 3 and arranged so as to be rotatable in the horizontal, and the bracing frame 4 is extended out of the carrying frame 3 and is supported on the tower 5 of the wind turbine. The rotor blade 11 extends vertically through the maintenance chamber 2. The rotor-blade inspection rig 1 is held by the cable, shown extending upward, on which the cable feedthrough winch 6, with the tilt compensation system 7, engages.

(55) FIGS. 4b and 4c show the rotor-blade inspection rig 1 in top view. The tower 5 of the wind turbine is shown in cross section, as a circle, against which the bracing frame 4 presses. The bracing frame 4 is accommodated by the carrying frame 3, on which the maintenance chamber is suspended. The bracing frame 4 is guided in a linear guide in the carrying frame 3, and in each inspection state is in alignment with the tower 5 of the wind turbine. The cable feedthrough winches 6 on both longitudinal struts of the carrying frame 3 receive the cable, coming from above from the direction of view, and are positionable along the carrying frame 3 by means of the tilt compensation system 7. The rotor blade 11 is represented in cross section.

(56) In FIG. 4c the maintenance chamber is shown having been turned, and it thus follows the twist of the rotor blade 11 in the vertical direction. The rotation axis for the maintenance chamber 2 in this case is located in the axis of the twist of the rotor blade 11. The adaptation of the position of the maintenance chamber 2 to the twist of the rotor blade 11 is effected by turning the maintenance chamber 2 relative to the fixed carrying frame 3.

(57) FIGS. 5a and 5b show rotor-blade inspection rigs 1 with a received rotor blade 11 in differing positions of the maintenance chamber 2 with respect to the rotor blade 11.

(58) In FIG. 5a, the rotor-blade inspection rig 1 is guided, by means of the adjustable bracing frame 4, on the tower 5 of the wind turbine. The tilt compensation is effected by means of displaceable cable feedthrough winches 6 on a tilt compensation system 7. In the position represented, the cable is only slightly inclined, the rotor-blade inspection rig 1 is located in the lower to middle region of the vertically adjusted rotor blade 11 of the wind turbine. The higher the rotor-blade inspection rig 1 is raised, the greater the cable inclination. The support of the maintenance chamber 2 by means of the carrying frame 3 and the bracing frame 4 is effected as far as an approach to approximately 10 m to the blade root, or to the rotor hub.

(59) FIG. 5b shows a position of the rotor-blade inspection rig 1 with a greater cable inclination. In the case of such inclinations of the cable, the rotor-blade inspection rig 1 becomes unstable and can no longer be guided safely, by means of the adjustable bracing frame 4, on the tower 5 of the wind turbine, by means of rollers of the bracing frame 4. In this region, a feed roller 10 is brought into engagement under automatic control, in order to increase the vertical support distance and thus to reduce the cable inclination. In this way, it is made possible to inspect the rotor blade 11 by means of the rotor-blade inspection rig 1 as far as the blade root of the rotor blade 11. The bracing frame 4 in this case is brought out of engagement and the rotor-blade inspection rig 1 is guided completely on the rotor blade 11. The tilt compensation is effected by means of displaceable cable feedthrough winches 6 on a tilt compensation system 7.

(60) FIGS. 6a and 6b show details of the sealing of the diaphragm system in relation to the rotor blade 11. The solid floor or roof element 15 forms the upper delimitation of the diaphragm system and is designed to be walkable.

(61) The small gap between the positionable diaphragm elements 13 and the rotor blade 11 renders possible the integration of a sealing system 17, 18 for thermal insulation and for protection against wind and against the ingress of rainwater or snow.

(62) In FIG. 6a, arranged as sealing elements on the diaphragm element 13 are plastic brushes, as a brush seal 17, the brushes of which are oriented horizontally along the inner contour of the movable diaphragm elements 13.

(63) Alternatively, as shown in FIG. 6b, the sealing is realized by means of inflatable sealing elements 18 or by a combination of a brush seal 17 and inflatable sealing elements 18.

(64) There are radially oriented support elements such as, for example, rollers or slide elements, not illustrated, installed along the contour of the movable diaphragm elements 13 to absorb lateral loads, for instance in the case of side wind.

(65) Represented in FIGS. 7a and 7b are the solid floor element 15, or the solid roof element 15 of the diaphragm systems of the chamber floor or chamber roof of a maintenance chamber 2. The positionable diaphragm elements 13 are translationally displaceable in relation to each other, in order to minimize the gap toward the rotor blade. The remaining gap is closed by the previously described sealing system. The elements of the diaphragm system, composed of a fixed floor element/roof element 15 and two positionable diaphragm elements 13, which are arranged over each other, are indicated in the illustrations by the representation of the lateral faces.

(66) Shown perspectively in top view in FIG. 7a is the diaphragm system with the solid floor element/solid roof element 15 with the diaphragm elements 13 completely closed, and therefore a completely closed floor and ceiling opening 12. This state is preferably assumed during the approach to and during the departure from the rotor-blade tip, and in the transport state.

(67) The diaphragm system is represented in the opened position in FIG. 7b, in which the floor/roof opening 12 for the rotor blade 11 can be seen as a contour.

(68) The diaphragm elements 13 in this case are completely extended, and the maintenance chamber 2 is thus ready to receive the rotor blade 11.

LIST OF REFERENCES

(69) 1 rotor-blade inspection rig 2 maintenance chamber 3 carrying frame 4 bracing frame 5 tower 6 cable feedthrough winch 7 tilt compensation system 8 inner railing 9 outer railing 10 feed roller 11 rotor blade 12 floor opening, roof opening 13 positionable diaphragm element 14 solid structural frame 15 solid roof element/solid floor element 16 lateral element, balcony 17 brush seal 18 inflatable sealing element 19 roof access