Method for assembling bearing components, bearing assembly, and wind power plant

Abstract

Proposed is a method for assembling non-rotatably interconnected components (2, 3) of a bearing assembly (1), comprising the following steps: - providing two rotationally symmetrical components (2, 3), namely a bearing ring (3) and an attachment component (2) to be connected thereto, wherein one of the two components (2, 3) has an annularly encircling depression (12, 15) on a surface facing toward the other component (3, 2), - filling the annularly encircling depression (12, 15) with an elastomer, and - pushing the two components (2, 3) together, wherein the component (2, 3) into which the elastomer was introduced provides a metal guide surface (4, 11) which adjoins the elastomer in the axial direction of the component (2, 3) in question, and wherein a metal surface (11, 4) of the second component (3, 2) is pushed beyond the guide surface (4, 11) until said metal surface (11, 4) lies force-transmittingly on the elastomer and is spaced in the axial direction from the guide surface (4, 11).

Description

[0001] Method for assembling bearing components, bearing arrangements and wind turbines

[0002] The invention relates to a method for assembling components of a bearing assembly that are connected to one another in a rotationally fixed manner. Furthermore, the invention relates to a bearing assembly, namely a rolling bearing assembly, and to a wind turbine having such a bearing assembly.

[0003] DE 10 2013 213 638 A1 discloses a bearing assembly and a method for assembling a bearing assembly. The bearing assembly is designed as a spherical roller bearing with an auxiliary assembly ring. During assembly, the auxiliary assembly ring is expanded by the pressure of a hydraulic fluid. The bearing assembly according to DE 10 2013 213 638 A1 is intended particularly for use in wind turbines.

[0004] DE 10 2015 206 438 A1 relates to a tapered roller bearing and a method for assembling the tapered roller bearing. Particular emphasis is placed on the assembly of the tapered roller bearing cage.

[0005] Another rolling bearing intended for use in a wind turbine, as well as an associated assembly method, is the subject of DE 10 2016 118 056 B4. The rolling bearing includes means for supplying lubricant and is designed as a double-row roller bearing.

[0006] WO 2015 / 067425 A2 deals with the assembly of a rolling bearing without an outer ring. Specifically, it concerns the mounting of planetary gears in a wind turbine gearbox. The assembly device proposed in WO 2015 / 067425 A2 includes, among other things, a support element with means for attachment to a crane. DE 10 2019 118 810 A1 addresses the issue of bearing ring creep in the direction of rotation around the rotational axis of a bearing. As a countermeasure against such bearing ring creep, which could lead to premature wear, the use of form-fitting components is recommended, which prevent both rotation and axial displacement of a bearing ring.

[0007] DE 86 26 727 U1 discloses a camshaft assembly consisting of a shaft tube and slipped-on elements. In this case, the risk of microslippage is to be reduced by expanding a tube during production.

[0008] Regarding the topic of creep of rolling bearing rings, reference is also made to the following publication:

[0009] Research Report FVA 479 IV, IGF No. 16985 BR, Research Association for Drive Technology, Remedial Measures for Rolling Bearing Migration, Definition and Design of Structural and Tribological Remedial Measures Against Tangential Migration of Rolling Bearing Rings, 2015

[0010] As part of the research project, various solutions, including form-fitting ones, were developed and their effectiveness was investigated experimentally and using complex 3D FE analyses. A steel intermediate ring placed between a bearing ring and a surrounding structure was investigated both experimentally and experimentally.

[0011] DE 10 2012 221 739 A1 describes a bearing assembly intended for use in a wind turbine, which comprises at least one rolling bearing, namely a tapered roller bearing. The rolling bearing has a first bearing ring connected to the rotor of the wind turbine and a second bearing ring connected to a housing. The first bearing ring connected to the rotor has a cylindrical seating surface with which it sits on a cylindrical portion of the rotor.

[0012] To prevent the bearing ring from cracking, DE 10 2012 221 739 A1 proposes machining the cylindrical seating surface with a hard turning process. Furthermore, a ring element made of fiber-reinforced plastic is arranged between an end face of the same bearing ring and an end face of a rotor shoulder designed for axial contact.

[0013] DE 10 2016 203 022 A1 discloses a method for heat-treating a steel alloy that can be used in the manufacture of bearings. This method also addresses the possibility of microslippage in bearing components. The bearing component can be, for example, a race of a rolling bearing.

[0014] The invention is based on the object of providing practical possibilities for bearing assembly which are particularly suitable for rolling bearings which comprise means against bearing ring creep caused by microslippage.

[0015] This object is achieved according to the invention by an assembly method having the features of claim 1. This method allows the assembly of a bearing assembly according to claim 4, which comprises two components connected in a rotationally fixed manner, in particular a bearing ring and a shaft. The bearing assembly is suitable, for example, for use in a wind turbine according to claim 10. The embodiments and advantages of the invention explained below in connection with the devices, i.e., the bearing assembly and the wind turbine, also apply mutatis mutandis to the method for assembling the components of the bearing assembly, i.e., the rolling bearing assembly, and vice versa. The method according to the application for assembling components of a bearing assembly, namely, the rolling bearing assembly, which are to be connected in a rotationally fixed manner, comprises the following steps:

[0016] - Provision of two rotationally symmetrical bearing components, namely a bearing ring and a connecting component to be connected thereto, wherein one of the two components has an annular recess on a surface facing the other component,

[0017] - Filling the annular recess with an elastomer,

[0018] - Pushing the two components of the bearing arrangement together, wherein the component into which the elastomer was previously introduced provides a metallic guide surface adjoining the elastomer in the axial direction of the component in question, and wherein a metallic surface of the second component is pushed beyond this guide surface until said metallic surface rests on the elastomer in a force-transmitting manner and is spaced apart from the guide surface in the axial direction.

[0019] This process uses a particularly gentle method to insert a damping elastomer that counteracts bearing ring migration between the components to be coupled—that is, the bearing ring and the connecting component. The connecting component is typically a shaft. Alternatively, the connecting component can be a housing or a part fixed to the housing.

[0020] If a bearing ring, i.e. inner ring, is to be mounted on a shaft, the inner ring can be heated in a conventional manner prior to assembly in order to at least slightly increase its diameter. The temperature of the inner ring must be limited to an amount that does not damage the elastomer layer. After assembly, the inner ring contracts. This temperature-induced contraction can be so extreme that, when the inner ring and other components of the bearing arrangement are at the same temperature, a cylindrical surface provided by the latter component, over which the guide ring was pushed during assembly, has a larger diameter than the inner peripheral surface of the inner ring. At least minimal elastic deformation of the inner ring and / or the other component during assembly and recovery upon completion of assembly, i.e. springback, can also play a role.

[0021] Regardless of whether and, if so, to what extent elastic and / or temperature-related deformations of metallic components, particularly in the form of expansion and subsequent contraction of the bearing ring, occur during assembly or after assembly, it can be provided that within the completed bearing arrangement, the elastomer layer absorbs the majority of the force flow between the bearing ring and the other component. In particular, a damping connection between the bearing ring and the connecting component, which transmits radial forces as well as forces in the circumferential direction, can be formed entirely by the elastomer layer. This means that the bearing ring is completely lifted off the connecting component, thus providing electrical insulation between the bearing ring and the connecting component.

[0022] The elastomer layer, which absorbs microslip through elastic deformation during operation of the bearing assembly and thus effectively counteracts bearing ring creep, is advantageously enclosed on almost all sides by the adjacent components, i.e., the bearing ring and the connecting component. This not necessarily perfect enclosure of the elastomer after assembly results in a hydrostatic stress state that is maintained over a very long service life of the bearing assembly.

[0023] The elastomer layer thickness, for example, is 0.25% to 5% of the maximum joint diameter between the two interconnected components of the bearing assembly. If the first component is a bearing ring designed as the inner ring of a rolling bearing assembly and the second component is a shaft on which the bearing ring is to be mounted, the maximum joint diameter corresponds to the inner diameter of the bearing ring, assuming a cylindrical inner surface of the bearing ring.

[0024] The annular recess into which the elastomer is embedded can be located either in the bearing ring or in the connecting component, such as a shaft. In both cases, the elastomer layer, measured in the axial direction of the bearing assembly, is covered by, for example, more than 90% of a metallic surface of the second component. This achieves the aforementioned effect of "locking" the elastomer between the components of the bearing assembly.

[0025] According to a possible refinement, the bearing assembly comprises, in addition to an elastomer layer that absorbs radial forces and is arranged in a cylindrical or conical space concentric with the center axis of the bearing assembly, an axially supporting, damping elastomer layer that is inserted into an annular disc-shaped recess in one of the two components. Both a radially loaded elastomer layer and an axially supporting elastomer layer can be divided into several flat areas. Such a division can, for example, take the form of circumferential segmentation.

[0026] The bearing assembly according to the application can, for example, be a rotor main bearing or a gearbox bearing in a wind turbine, regardless of the number and shape of the elastomer layers. In both cases, the bearing assembly is designed, for example, as a tapered or cylindrical roller bearing. Regardless of the shape of the rolling elements, the bearing assembly, particularly in the form of a slewing bearing, can also be used in other stationary systems. The bearing assembly can also be used in a mobile machine.

[0027] During normal operation of the bearing assembly, the elastomer layer may experience compression due to the bearing load. For example, in a bearing assembly with a joint diameter of several thousand mm and elastomer thicknesses of a few mm, this compression is in the order of a few tens of microns. The shear stresses that occur simultaneously in the elastomer layer have no significant impact on the service life of the bearing assembly.

[0028] Compared to conventional large-diameter bearings constructed without elastomer layers between a bearing on the one hand and a shaft or housing on the other, the bearing arrangement according to the application is characterized by improved acoustic properties and reduced joint pressure acting between the interconnected components. This reduced joint pressure allows the use of bearings with a relatively thin thickness compared to conventional solutions. Regarding media compatibility, the choice of materials for the bearing ring and the connecting component must be tailored to the specific application.

[0029] Two exemplary embodiments of the invention are explained in more detail below with reference to a drawing. In the drawings:

[0030] Fig. 1 in a sectional view of components of a bearing arrangement, wherein the components are coupled to each other via elastomer layers

[0031] Fig. 2 a detail D1 from Figure 1 ,

[0032] Fig. 3 shows an alternative embodiment of a bearing arrangement including several elastomer layers in a sectional view analogous to Figure 1,

[0033] Fig. 4 a detail D3 from Figure 3.

[0034] The following explanations refer to both exemplary embodiments, unless otherwise stated. Parts that correspond to one another or have essentially the same function are designated by the same reference numerals in all figures. A bearing arrangement, designated overall by the reference numeral 1, is intended for use in a wind turbine (not shown in detail). The bearing arrangement 1 is a tapered roller bearing for supporting a shaft 2, which is generally referred to as a connecting part or connecting component. A bearing ring 3, i.e. the inner ring, contacts both a cylindrical surface 4 and an axial stop surface 7 of the shaft 2. A rolling element raceway, on which tapered rollers (not shown) roll, is designated 8. The bearing arrangement 1, in a basic design known per se, is capable of absorbing radial forces and additional axial forces in one direction.

[0035] The bearing ring 3 and the connecting component 2 are generally referred to as components 3, 2 of the bearing assembly 1. In each exemplary embodiment, one of the two components 2, 3 is provided with an annular recess 12, 15, which lies opposite a cylindrical surface 4, 11 of the other component 3, 2. 11 denotes the inner surface of the bearing ring 3. In each case, an elastomer layer 5 is located in the annular recess 12, 15, which is subject to radial forces and thereby absorbs micromovements between the components 2, 3 to counteract bearing ring creep.

[0036] In the configuration shown in Figures 1 and 2, the cylindrical inner surface 11 of the bearing ring 3, adjacent to the recess 12, acts as a guide surface, which is important during assembly of the bearing arrangement 1. Assuming that the shaft 2 is stationary, the bearing ring 3 is pushed onto the shaft 2 from right to left, based on the arrangement shown in Figure 1. Initially, the cylindrical inner surface 11, i.e., the guide surface, contacts the cylindrical surface 4 of the shaft 2. The latter surface 4 is generally referred to as the metallic surface.The elastomer layer 5 is, as can be seen in particular from Figure 2, set back from the cylindrical inner surface 11, i.e. countersunk into the annular recess 12, so that when the inner ring 3 is pushed onto the shaft 2, contact between the shaft 2 and the inner ring 3 is avoided as long as the cylindrical inner surface 11 slides on the shaft 2. Only towards the end of the pushing-on process is the cylindrical inner surface 11 used as a guide surface pushed out beyond the cylindrical surface 4 of the shaft 2, resulting in the arrangement shown in Figure 2. The cylindrical surface 4 can, as shown in exaggerated form in Figure 2, jump into the recess 12, although this process does not necessarily occur suddenly.Rather, the partial immersion of the shaft 2 into the recess 12 may represent a process that results primarily or exclusively from temperature-induced dimensional changes of the components 2, 3. It is assumed here that the bearing ring 3 is heated prior to assembly. Ultimately, as can be seen from Figure 2, there is an overlap between the shaft 2 and the bearing 3 in the radial direction.

[0037] As can be seen from Figures 1 and 2, the metallic base body of the bearing ring 3 is raised from the shaft 2 across its entire width. This means that only the elastomer layer 5 creates a connection between the components 2, 3, thereby transmitting radial forces. In Figure 2, an annular shoulder on the bearing ring 3 is designated by 13, and a similarly annular shoulder on the shaft 2 is designated by 14.

[0038] In the embodiment according to Figure 1, as in the embodiment according to Figure 3, in addition to the elastomer layer 5, an elastomer layer 6 is present, which is located on one end face of the bearing ring 3. In the end face of the bearing ring 3, designated 9, an annular disc-shaped recess 10 can be seen, which is filled with an elastomer, which protrudes slightly beyond the end face 9, so that only the elastomer layer 6 is in contact with an axial stop surface 7 of the connecting component 2. Thus, there is no metal-to-metal contact between the bearing ring 3 and the connecting component 2.

[0039] The embodiment according to Figures 3 and 4 differs from the embodiment according to Figures 1 and 2 in that the radially supporting elastomer layer 5 is not located on the bearing ring 3, but in the annular circumferential recess of the shaft 2, designated 15. In the case of Figure 3, the cylindrical surface 4 of the connecting component 4 is used as a guide surface during assembly, whereby here too the bearing ring 3 is pushed onto the shaft 2 from right to left. The cylindrical inner surface 11 of the inner ring 3 slides on the guide surface 4 until the aforementioned metallic inner surface 11 loses contact with the guide surface 4 and is only supported on the elastomer layer 5, as sketched in Figure 4.

[0040] List of reference symbols

[0041] Bearing arrangement

[0042] Shaft, connecting component

[0043] Bearing ring cylindrical surface, guide surface

[0044] Elastomer layer, cylindrical, radially supporting

[0045] Elastomer layer, ring-shaped, axially supporting axial stop surface

[0046] Rolling element raceway

[0047] End face of the bearing ring, annular disc-shaped depression, cylindrical inner surface of the bearing ring, guide surface, annular recess in the bearing ring, annular recess around the running shoulder on the bearing ring, annular recess around the running shoulder on the shaft, annular recess in the shaft

Claims

Patent claims 1 . Method for assembling non-rotatably connected components (2, 3) of a bearing arrangement (1), comprising the following steps: - Providing two rotationally symmetrical components (2, 3), namely a bearing ring (3) and a connecting component (2) to be connected thereto, wherein one of the two components (2, 3) has an annular circumferential recess (12, 15) on a surface facing the other component (3, 2), - filling the annular recess (12, 15) with an elastomer, - pushing the two components (2, 3) together, wherein the component (2, 3) into which the elastomer has been introduced provides a metallic guide surface (4, 11) which adjoins the elastomer in the axial direction of the relevant component (2, 3), and wherein a metallic surface (11, 4) of the second component (3, 2) is pushed beyond the guide surface (4, 11) until said metallic surface (11, 4) rests on the elastomer in a force-transmitting manner and is spaced apart from the guide surface (4, 11) in the axial direction.

2. Method according to claim 1, characterized in that the bearing ring (3) is pushed onto a shaft (2) as a connecting component.

3. Method according to claim 2, characterized in that the bearing ring (3) undergoes a contraction after its guide surface (11) has been pushed beyond the metallic surface (4) of the shaft (2).

4. Bearing arrangement (1 ), comprising two components (2, 3) coupled to one another in a rotationally fixed manner, namely a bearing ring (3) and a connecting component (2), wherein one of the two components (2, 3) has an annular recess (12, 15) filled with an elastomer, which extends over the predominant part of the width of the bearing ring to be measured in the axial direction (3) and is provided as a damping intermediate layer counteracting micro-movements between the said components (2, 3).

5. Bearing arrangement (1) according to claim 4, characterized in that the annular recess (12) filled with the elastomer is located in the bearing ring (3).

6. Bearing arrangement (1) according to claim 4, characterized in that the annular circumferential recess (15) filled with the elastomer is formed by a shaft (2) on which the bearing (3) is mounted.

7. Bearing arrangement (1) according to one of claims 4 to 6, characterized in that the elastomer is present as a layer (5) whose thickness corresponds to at least 0.025% and at most 0.5% of the joint diameter given by the two components (2, 3).

8. Bearing arrangement (1) according to one of claims 4 to 7, characterized in that the elastomer layer embedded in one of the two components (3, 2) is provided to absorb the largest part of the radial load acting between the two components (2, 3), wherein it is covered to more than 90% by a metallic surface (4, 11) of the second component (2, 3).

9. Bearing arrangement (1) according to one of claims 4 to 8, characterized in that it additionally has an axially supporting, damping elastomer layer (6) which is introduced into an annular disc-shaped recess (10) in one of the two components (2, 3).

10. Wind turbine comprising at least one bearing arrangement (1) according to claim 4.

Images