METHOD AND DEVICE FOR REPLACING A USED BEARING, IN PARTICULAR FOR REPLACING A MAIN BEARING OF A WIND TURBINE, AND BEARING ARRANGEMENT IN PARTICULAR OF A WIND TURBINE

Abstract

For replacing in particular a used main bearing of a wind turbine, a bearing housing is first pulled axially off the main bearing along a rotor shaft, then the used main bearing is divided and disassembled. A new main bearing is assembled around the rotor shaft and the original bearing housing is pushed axially back onto the main bearing. During the replacement of the main bearing, the rotor shaft is supported on a machine carrier by means of a holding device, wherein the holding device is arranged at least partially in the region between a bearing seat and a hub-side end region of the rotor shaft.

Claims

1-25. (canceled)

26. A method for replacing a used bearing, wherein the used bearing is arranged during operation at a bearing seat and supports a rotor shaft extending along an axis of rotation and in an axial direction towards a rotor hub as part of a rotor unit, the used bearing is arranged in a bearing housing designed as a one-piece, non-divided bearing housing and is fastened to a machine carrier; the method comprises: without disassembly of the rotor shaft, removing the bearing housing from the used bearing by axial displacement, dividing the used bearing, and removing the used bearing from the rotor shaft; mounting a new bearing around the rotor shaft; and arranging the new bearing in the bearing housing after removing the used bearing from the rotor shaft.

27. The method according to claim 26, the method further comprising axially displacing the bearing housing by an extraction device supported on the bearing housing.

28. The method according to claim 26, the method further comprising supporting the rotor shaft with a holding device arranged on a side of the bearing seat opposite the rotor unit in the axial direction.

29. The method according to claim 26, wherein the bearing has a plurality of add-on parts selected from the group consisting of a seal cover, a seal carrier, a spacer ring, and a shaft nut, the method further comprising axially displacing at least one add-on part in a non-destructive manner and reusing the add-on part with the new bearing.

30. The method according to claim 26, the method further comprising heat treating the bearing housing to facilitate disassembly and/or assembly.

31. The method according to claim 26, the method further comprising removing the bearing housing from the used bearing while the used bearing is in the bearing seat.

32. The method according to claim 26, the method further comprising displacing the used bearing together with the bearing housing along the axis of rotation before removing the bearing housing from the used bearing.

33. The method according to claim 26, wherein the bearing has an inner ring, an outer ring, and rolling elements arranged therebetween, the method further comprising: mounting the new bearing at least partially around the rotor shaft as a partially assembled bearing; and pushing the bearing housing together with remaining bearing components, that complete the partially assembled bearing, onto the partially assembled bearing in the axial direction.

34. The method according to claim 26, wherein the bearing is a double row bearing having two rows of rolling elements and an outer ring of the new bearing is divided into a plurality of outer ring parts as viewed in the axial direction, the method further comprising partially assembling the new bearing, and sliding one of the outer ring parts onto the partially assembled bearing together with the bearing housing.

35. The method according to claim 33, wherein the outer ring has a hub-side outer ring part and, opposite thereto, a transmission-side outer ring part, the method further comprising pushing the transmission-side outer ring part with the bearing housing onto the partially assembled bearing before assembling a hub-side outer ring part.

36. The method according to claim 26, the method further comprising providing a lifting device and lifting the rotor shaft during bearing replacement.

37. The method according to claim 26, wherein the used bearing is sealed by a sealing system, the method further comprising replacing the sealing system with a new and different sealing system during bearing replacement.

38. The method according to claim 26, wherein the used bearing is a main bearing of a wind power plant.

39. A bearing arrangement of a wind power plant, the bearing arrangement comprising a bearing arranged in a bearing housing, said bearing having been replaced, wherein the bearing housing is a used one-piece bearing housing and wherein the bearing is a divided bearing.

40. A device for the replacement of a bearing of a plant, the device comprises: a rotor unit having a rotor shaft, which extends in an axial direction to a rotor hub; a machine carrier; a bearing for supporting said rotor shaft, which is positioned at a predetermined bearing seat during operation; a bearing housing surrounding said bearing, said bearing housing being fastened to said machine carrier during operation; and a holding device fastened to said machine carrier for holding said rotor shaft, said holding device being arranged at least partially in a region between said bearing seat and said rotor hub.

41. The device according to claim 40, further comprising a rotor lock disc with at least one locking hole arranged on said rotor shaft, oriented on an end side towards said rotor hub, and a retaining device fastened to said rotor lock disc via a respective bolt engaging in said at least one locking hole.

42. The device according to claim 40, further comprising a lifting device configured to lift said rotor shaft relative to said machine carrier.

43. The device according to claim 42, further comprising a base region of said holding device, said lifting device being configured to effect a lifting at said base region of said holding device from said machine carrier, so that said holding device as a whole can be lifted together with said rotor shaft.

44. The device according to claim 40, wherein said holding device is fastened to said rotor unit and to said machine carrier, said holding device being configured to be rotatable relative to said machine carrier about a pivot axis.

45. The device according to claim 40, further comprising a linear guide, said bearing housing being fastenable to said linear guide and slidable relative said linear guide.

Description

[0068] An embodiment example is explained in more detail below with reference to the figures. Simplified illustrations show:

[0069] FIG. 1 a first sectional perspective view of a bearing arrangement of a main bearing of a wind turbine on a machine carrier,

[0070] FIG. 2 a second sectional perspective view of the bearing arrangement according to FIG. 1, looking at the main bearing.

[0071] FIG. 3 a sectional cross-sectional view of the bearing arrangement according to FIG. 1

[0072] FIG. 4 an enlarged sectional view in the region of the main bearing,

[0073] FIG. 5A a first perspective sectional view of the bearing assembly according to FIG. 1, looking at the bearing during replacement of the bearing,

[0074] FIG. 5B a second perspective sectional view similar to FIG. 5A, but with a linear guide,

[0075] FIG. 6 a sectional view similar to FIG. 3, during a replacement situation, with a bearing housing removed from the bearing, and

[0076] FIG. 7 a perspective view similar to FIG. 2 with an alternative variant for the holding device.

[0077] The figures respectively show a bearing arrangement 2 of a wind turbine not shown in more detail here. The bearing arrangement comprises a bearing 4, in particular the so-called main bearing of such a wind turbine, as well as a bearing housing 5. The bearing arrangement 2 furthermore preferably includes a rotor shaft 6, which is supported by the bearing 4 and can rotate about an axis of rotation 8 du-ring operation. The rotor shaft 6 extends from a rear, transmission-side region in the axial direction 10 to a front, hub-side end of the rotor shaft 6. A rotor hub 12 is fastened to said hub-side end in the operating state, as shown in highly simplified form in FIG. 3.

[0078] As can be seen in particular, for example, from the cross-sectional view according to FIG. 3, the rotor shaft 6 widens towards its hub-side end to form a type of connecting flange for fastening to the rotor hub 12. Furthermore, a so-called rotor lock disk 14 designed as a ring is fastened to said connecting flange.

[0079] In the embodiment example, the bearing 4 is arranged directly adjacent to the hub-side, widening connecting flange of the rotor shaft 6. In the rear region, the rotor shaft 6 in the embodiment example is connected to a transmission 16. In transmissionless embodiments, the rotor shaft 6 is directly connected to a generator or respectively a generator rotor. The entire bearing arrangement 2 as well as the transmission 16 or respectively the generator are thereby arranged on a machine carrier 18. Said machine carrier 18 is generally characterized in that it has two lateral support surfaces 20, between which a free space is formed, into which the transmission 16, but in particular also the bearing arrangement 2, i.e. the bearing 4, the bearing housing 5 and preferably also the rotor shaft 6, is partially immersed. In particular, the machine carrier 18 is approximately half-shell-like at least in the front region where the bearing 4 is located. Both the bearing 4 and the transmission 16 are supported on the support surfaces 20.

[0080] Furthermore, a holding device 22 is shown in the figures, by means of which the rotor shaft 6 is supported on the machine carrier 18 during a bearing exchange. For this purpose, the holding device 22 generally has a crossmember 24 extending above the rotor shaft 4 and two lateral support struts 26, which are supported on the supporting surfaces 20 of the machine carrier 18. The two support struts 26 are each preferably formed by an approximately triangular supporting frame in the embodiment example. Furthermore, a lifting device 28 is arranged on the holding device 22, which is designed for lifting the holding device 22 with respect to the supporting surfaces 20. Said lifting device 28 has, for example, electrically or hydraulically operable and extendable stamps or adjusting screws.

[0081] Bolts 30 are inserted via through holes in the crossmember 24, and when the bearing 4 is moved to replace it, they engage corresponding locking holes 32 in the rotor lock disk 14.

[0082] The bearing 4 is generally arranged in the bearing housing 5. Said bearing housing 5 is an annular element, which fully surrounds the bearing 4 and has two opposing fastening flanges 36, which therefore project radially. Said fastening flanges 36 rest on the support surfaces 20 of the machine carrier 18. The bearing housing 5 is typically fastened to the machine carrier 18 with screws. In the embodiment example, the bearing housing 5 has two spaced-apart circumferential stiffening ribs on the outside.

[0083] The design of the bearing 4 can be seen in particular from FIGS. 3 to 6. The bearing 4 has an inner ring 38, an outer ring 40 and rolling elements 42 arranged between them. These are typically arranged in a bearing cage 44. In the embodiment example, the bearing 4 is designed as a double-row roller bearing. Furthermore, the bearing arrangement 2 has a spacer ring 46 on each side. In the embodiment example, the hub-side spacer ring 46 is supported on a stop surface of the rotor shaft 6. The transmission-side spacer ring 46 rests against a shaft nut 48. The inner ring 38 is held clamped between the two spacer rings 46. Two lateral, annular housing or seal covers 50 are also associated with the bearing housing 5. In the embodiment example, the inner ring 38 and the outer ring 40 are each non-divided in the axial direction 10. Alternatively, the outer ring 40 is divided in the axial direction into a hub-side outer ring part 52A and a transmission-side outer ring part 52B. In the present case, hub-side is always understood to mean the region facing the rotor hub 12 in the axial direction 10 and transmission-side the opposite region. This alternative design is illustrated in FIG. 4 by a dashed dividing line.

[0084] FIGS. 1 and 2 show an initial situation with an old, used bearing 4, in the normal installation situation, in which the bearing housing 5 is fastened to the machine carrier 18 and accommodates the bearing 4, in which the rotor shaft 6 is mounted. Fastened to the hub side of the rotor shaft 6 is a so-called rotor star, which is not shown in more detail here. Said rotor star has the rotor hub 12 and rotor blades fastened to it. The arrangement shown in the figures is generally located in wind turbines at the upper end of a tower within a so-called nacelle, which is typically rotatable about a vertical axis.

[0085] The holding device 22 shown is typically arranged and fastened temporarily. In the embodiment example, the holding device 22 is positively or non-positively fastened to the rotor lock disk 14 via the bolts 30 as described. For replacing the bearing 4, it is proceeded as follows:

[0086] First, the add-on parts, in particular the shaft nut 48, the transmission-side spacer ring 46 and the transmission-side seal cover 50 are pulled off counter to the axial direction 10 along the rotor shaft 6 to the rear in the direction of the transmission 16. Then the bearing housing 5, which was previously detached from the machine carrier 18, is also pressed off or pulled off from the bearing 4 towards the rear in the opposite direction to the axial direction 10.

[0087] The bearing 4 is then disassembled. If the bearing is a divided bearing, the individual ring segments are separated from each other non-destructively if necessary. In the case of a non-divided bearing, destructive disassembling typically takes place by separating the bearing rings 38, 40 into individual sections, for example by separation welding. The spent bearing parts are removed and then a new bearing 4 is built around the rotor shaft 6. In this case, the new bearing 4 is necessarily designed as a divided bearing 4. Both the inner ring 38 and the outer ring 40 are divided into individual ring segments, each of which is fitted around the axis of rotation 8 and thus around the rotor shaft 6. FIG. 5B shows such a divided bearing with ring segments 54 for the outer ring 40.

[0088] In the embodiment shown in FIG. 5B, the new bearing 4 is built up in the region of a bearing seat 56. The bearing seat 56 is defined by the position that the bearing 4 assumes during operation. Especially, the bearing seat 56 is defined by the region between the two spacer rings 46.

[0089] In FIG. 5B—as an essential difference to the situation in 5A—a linear guide 58 is additionally illustrated. The linear guide 58 is fastened, in particular temporarily, preferably to the holding device 22, in particular to its support struts 26. Alternatively, the linear guide 58 can also be fastened to the machine carrier 18. The linear guide 58 is designed, for example, in the manner of a rail. Guide elements not shown in more detail here engage in this linear guide 58, which are either part of the bearing housing 5 or are connected to it. Via the linear guide 58, an exact and, as far as possible, tolerance-free displacement of the bearing housing 5 in and against the axial direction 10 is ensured. This is particularly advantageous for mounting, i.e. pushing the bearing housing onto the new bearing 4 due to the small gap dimensions.

[0090] To simplify assembly, the rotor shaft 6 is lifted slightly via the lifting device 28 mentioned, for example in the range of a few mm to a few centimeters (for example 1-2 centimeters), so that the bearing housing 5 is load-free overall, i.e. no longer rests under load on the support surfaces 20. For easier assembly/disassembly, the bearing housing 5 is preferably also heated, so that it expands slightly radially.

[0091] FIG. 6 shows a sectional view through a situation similar to FIG. 5A, in which the bearing housing 5 is pressed off or pulled off backwards against the axial direction 10. In FIG. 6, an annular segment 54 of the outer ring 40 is shown only in the lower half of the picture. In the upper half of the figure, this ring segment 54 is still missing. Starting from the situations shown in FIGS. 5A, 5B and 6, the bearing housing 5 is pushed back onto the assembled bearing 4 in the axial direction 10. The same applies to the add-on parts such as spacer ring 46 and shaft nut 48.

[0092] FIG. 7 shows an alternative variant for the holding device 22, in which the support struts 26 are fastened directly to the rotor unit, in particular to the rotor lock disk 14.

[0093] A longitudinal member 62 is connected to a respective support strut 26, which is connected to the machine carrier 18 at a pivot or tilt bearing 64. The longitudinal beam 62 can be rotated about a pivot axis 66 defined by the tilt bearing 64. When the rotor unit is lifted in the front region on the hub side, the longitudinal member 62 slightly rotates about the pivot axis 66. The longitudinal member 62 is therefore designed in the manner of a rocker arm. The tilt bearing 64 is preferably located in a rear region on the transmission side, in particular on a transmission support, i.e. on a support structure, by means of which the transmission 16 (not shown in FIG. 7) is supported on the machine carrier 18.

[0094] In FIG. 7, a support strut 26 and the longitudinal member 62 are shown on one side only. Preferably, a support strut 26 and a longitudinal member 62 are arranged on both sides.

[0095] Also in the embodiment according to FIGS. 2 to 6, the holding device 22 is preferably connected to the machine carrier 18 via a tilt bearing 64. Conversely, also in the embodiment according to FIG. 7, the lifting device 28 and preferably also the linear guide 58 are provided.

[0096] The axial displacement of the bearing housing 5 relative to the used bearing 4 is carried out by means of an auxiliary device not shown in more detail here, in particular by means of a pushing-off device. Said pushing-off device has one or more (hydraulic) stamps, which are supported on the rotor unit on the one hand and on the bearing housing on the other.

[0097] The replacement concept presented here is preferably used for three-point bearing arrangements as well as four-point bearing arrangements of wind turbines. However, the replacement concept described here is not limited to such applications.

[0098] The starting point of the replacement concept is, on the one hand, that the bearing 4 is replaced without disassembling the rotor shaft 6 and, on the other hand, that the bearing housing 5 is only pushed off/pulled off axially and then pushed back onto the new bearing 4. The bearing housing 5 is in particular a one-piece, monolithic component, which is therefore not divided into individual housing halves or ring segments.

TABLE-US-00001 List of reference signs  2 bearing arrangement  4 bearing  5 bearing housing  6 rotor shaft  8 axis of rotation 10 axial direction 12 rotor hub 14 rotor lock disk 16 transmission 18 machine carrier 20 support surfaces 22 holding device 24 crossmember 26 support struts 28 lifting device 30 bolts 32 locking holes 36 fastening flanges 38 inner ring 40 outer ring 42 rolling elements 44 bearing cage 46 spacer ring 48 shaft nut 50 sealing cover 52A hub-side outer ring part 52B transmission-side outer ring part 54 ring segments 56 bearing seat 58 linear guide 60 62 longitudinal member 64 tilt bearing 66 pivot axis