EP4713568A1 - Leveling assemblies for rotating machines and use of such assemblies - Google Patents

Abstract

The present disclosure relates to an elevation and leveling assembly for supporting a rotating machine. The assembly comprises a base block defining an inner space for receiving one or more shim plates and the leveling assembly further comprises a washer assembly. The washer assembly comprises a bowl configured for being received in the inner space and on top of the shim plates and has a curved top surface. The washer assembly further comprises a washer with a curved bottom surface that is complementary to the curved top surface of the bowl such that the washer can tilt with respect to the bowl. The washer assembly has a sliding top surface for supporting the rotating machine. The present disclosure further relates to turbomachines, and more particularly steam turbines supported by such assemblies and to power plants including such steam turbines and also relates to the use of such leveling assemblies.

Description

LEVELING ASSEMBLIES FOR ROTATING MACHINES AND USE OF SUCH ASSEMBLIES

FIELD

[0001] The present disclosure relates to assemblies for leveling and elevating a rotating machine, particularly a steam turbine. The present disclosure further relates to the use of such assemblies in methods for leveling a rotating machine.

BACKGROUND

[0002] Steam turbines are rotary mechanical devices that generate mechanical energy from a steam that flows through the turbine. For example, electrical power may be generated when the turbine is connected to a generator. Modern steam turbines are used in a wide variety of applications, such as in power plants and in industrial locations. Steam is allowed to expand in the turbine, usually in multiple stages, which results in rotation of the rotor of the turbine. A steam turbine may comprise sections which operate at different pressures. A steam turbine may for example comprise a high-pressure (HP) section, an intermediate pressure (IP) section and a low-pressure (LP) section.

[0003] In large machinery of this kind, it is important that the machine and optionally other apparatus connected to it, are properly leveled. For example, for proper operation of a power plant it is important that the turbine shaft is correctly aligned with the generator.

[0004] An important challenge in relation with steam turbines is the control and absorption of vibrations, rotor imbalance, and thermal expansion. Similar challenges arise in other turbomachinery, including e.g. gas turbines and other large rotating machinery like large generators.

[0005] That is, the alignment of different machines or components is to be maintained in the case of turbomachinery in the presence of varying thermal expansion and contraction, oscillation vibrations and high, varying, and complex loads.

[0006] It is known in the art to establish precise elevation or alignment in a commissioning phase of a turbomachine e.g., a steam turbine, using heavy duty supports and then grout these supports to lock-in the position for the life of the machine. It has however been found that foundations upon which the turbomachines are mounted may settle over time, resulting in misalignment of some parts.

[0007] US 5,573,220 discloses a foundation mount for leveling machinery which is adjustable over time. That is, a potential misalignment that occurs over time may be corrected. The mechanism described in this prior art document is based on the adjustment of a screw to horizontally displace a wedge, which is in contact with a lower surface of a riser. The riser is vertically displaced as a result thereof.

[0008] However, it has been found that such adjustable foundation mounts can break depending on the operational dynamic loads of the machinery they are designed to support, particularly in the case of large steam turbines.

[0009] The present disclosure therefore provides foundation mounts that at least partially resolve some of the aforementioned problems.

SUMMARY

[0010] In an aspect of the present disclosure, a leveling assembly for supporting a rotating machine is provided. The leveling assembly comprises a base block defining an inner space for receiving one or more shim plates and the leveling assembly further comprises a washer assembly. The washer assembly comprises a bowl and a washer supported by the bowl. The bowl is configured for being received on top of the shim plates in the inner space and has a curved top surface. The washer has a curved bottom surface that is complementary to the curved top surface of the bowl such that the washer can tilt with respect to the bowl. The washer assembly further has a sliding top surface for supporting the rotating machine.

[0011] In accordance with this aspect, a turbine or other rotating machine can be supported directly on the leveling assembly, which is adjustable by incorporating shim plates. If more shim plates are positioned in the inner space, the washer assembly is raised. If fewer shim plates are positioned in the inner space or shim plates are removed from the inner space, the washer assembly can be lower(ed).

[0012] Shim plates may herein be regarded as thin plates, typically metal plates, which can be stacked on top of each other. By adjusting the stack of shim plates, the height of the washer assembly can be adjusted. The use of shim plates allows for adjustment of leveling, but makes the construction of the leveling assembly more robust than adjustable prior art devices and more capable of absorbing operational dynamic loads of the rotating machinery it is designed to support, thereby extending the lifetime of the leveling assembly and of the machinery. [0013] The washer assembly can tilt thanks to complementary curved surfaces and allows alignment of the washer assembly with respect to the rotating machine and thereby reduce loads. Complementary surfaces may herein be understood to refer to surfaces that are adapted to each other and precisely fit together. The sliding top surface promotes good contact with the rotating machine and limits line-loading by allowing sliding for compensating for thermal expansion of components of the rotating machine.

[0014] A sliding top surface may herein be regarded as a surface with a specifically selected coefficient of friction that is suitable for sliding. A suitable coefficient of friction may be determined by the skilled person depending on the structure that is to be supported and material thereof.

[0015] In some examples, the leveling assembly may further comprise a first lateral panel for laterally closing the inner space of the base block at a first side, and comprise a second lateral panel for laterally closing the inner space of the base block at a second side and for retaining the shim plates and the bowl in the inner space.

[0016] The lateral panels can retain the shim plates and the bowl of the washer assembly to maintain their position in the inner space. The lateral panels may be removably mounted to the base block, e.g. with bolts. A lateral panel may thus be removed to adjust the number of shim plates as needed for leveling. Such an adjustment may take place both during original installation and commissioning of a machine, as well as during the lifetime, e.g. after a foundation has settled.

[0017] In some examples, the sliding surface of the washer assembly may be included in a sliding element mounted to the top of the washer, i.e. the washer assembly may comprise a separate element with a suitable coefficient friction may be provided. In further examples, specific surface treatments and/or coatings may be used to provide the top surface with a suitable coefficient of friction for promoting sliding between the top surface and the rotating machine that it supports.

[0018] In a further aspect of the present disclosure, a turbomachine is provided, which is supported by one or more leveling assemblies according to any of the examples herein disclosed. The turbomachine may be a steam turbine or a gas turbine.

[0019] In yet a further aspect of the present disclosure, a fossil, renewable-energy, waste- to-energy, combined-cycle or nuclear powerplant is provided, which comprises such a turbomachine or steam turbine with leveling assemblies.

[0020] In yet a further aspect of the present disclosure, use of a leveling assembly according to any of the examples herein disclosed for leveling of a rotating machine is provided. The leveling assembly comprises a base block defining an inner space for receiving one or more shim plates and further comprises a washer assembly. The washer assembly comprises a bowl and a washer supported by the bowl, wherein the bowl is configured for being received in the inner space and on top of the shim plates and wherein the bowl has a curved top surface. The washer is configured for being received in the bowl, and has a curved bottom surface that is complementary to the curved top surface of the bowl such that the washer can tilt with respect to the bowl, and the washer assembly further has a sliding top surface for supporting the rotating machine.

[0021] The use comprises inserting said one or more shim plates into the inner space of the base block, or removing said one or more shim plates from the inner space of the base block. The use further comprises laterally closing the inner space by mounting of a lateral panel to a side of the base block.

[0022] A plurality of leveling assemblies may be used to support the rotating machine, and each of the leveling assemblies may be adjusted as needed to provide a level support for the rotating machine.

[0023] The leveling assembly may comprise a first and a second lateral panel for laterally closing the inner space of the base block at a first and a second side respectively. The first and second lateral panels may be configured for retaining the shim plates and bowl in the inner space. When introducing shim plates into or removing shim plates from the inner space, the inner space may be closed on one side, e.g. by one of the lateral panels. The inner space in the base block and lateral panel can ensure correct positioning of the shim plates within the inner space. Once the appropriate number of shim plates has been placed, the inner space may be laterally closed to retain the shim plates securely in position by mounting the other of the lateral panels. Prior to closing the inner space, the washer assembly has been positioned on top of the shim plates.

[0024] The use of the leveling assembly may be repeated over time as needed. Particularly, one or more of the lateral panels may be removably mounted. By removing one of the lateral panels, access may be provided for removing the washer assembly and subsequent adjustment of the number of shim plates.

[0025] In some examples, the use may further comprise, before the step of inserting or removing said one or more shim plates, lifting the rotating machine with one or more jacks and positioning the leveling assembly under the rotating machine. In examples, the use of the leveling assembly may further comprise, after the step of laterally closing the inner space, lowering the rotating machine with one or more jacks and removing the jacks. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 schematically illustrates an example of a first example of a leveling assembly; and

[0027] Figures 2A - 2C schematically illustrate another example of a leveling assembly.

DETAILED DESCRIPTION OF EXAMPLES

[0028] Reference now will be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation only, not as a limitation. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Even more, embodiments can be combined together. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0029] Figure 1 schematically illustrates an exploded view of an example of a leveling assembly 40. The leveling assembly 40 can support a rotating machine, such as a steam turbine or another turbomachine. A plurality of such leveling assemblies 40 may be provided to support a steam turbine. Each of the leveling assemblies 40 may support a different part or component of a steam turbine. For example, a steam turbine may include a plurality of feet or pedestals, and one such leveling assembly may be arranged with each individual pedestal.

[0030] The leveling assembly 40 comprises a base block 10 defining an inner space 15 for receiving one or more shim plates 20 and further comprises a washer assembly 30 configured for being received in the inner space and on top of the shim plates 20. The inner space 15 may be centrally arranged in the base block, and may be at least partially closed at the sides to retain the shim plates and part of the washer assembly 30.

[0031] In the illustrated example, the inner space 15 is arranged between two upstanding flanges or sidewalls 19 of the base block 10. The inner space 15 in the illustrated example is substantially square, but other shapes are foreseen within the scope of the present disclosure, e.g. rectangular, or other polygonal shapes.

[0032] In some examples, the leveling assembly may comprise one or more shim plates. The shim plates 20 may have a shape and dimensions adapted to the inner space 15 such that they fit in the inner space 15 without significant clearance in the inner space and can be retained by the sidewalls of the inner space 15. In this case, the shim plates 20 are shown to be substantially square.

[0033] A single shim plate 20 or a single stack of shim plates is schematically illustrated in figure 1 . It should be clear however that depending on the needs and circumstances, multiple shim plates may be stacked on top of each other to thereby adjust the height of the washer assembly.

[0034] Stacking and removing of shim plates 20 thus allows adjusting the height of the washer assembly 30 which supports the rotating machine. In order to level a steam turbine or other rotating machine, each of the individual leveling assemblies may be adjusted by including more or less shim plates 20. The shim plates 20 may be very thin and thereby allow very precise leveling and alignment.

[0035] The washer assembly 30 comprises a washer 24 with a convex rounded bottom surface, and a bowl 22 with a concave top surface that is complementary to the convex rounded bottom surface of the washer 24. The washer 24 is received in the bowl 22 such that the washer 24 can tilt with respect to the base block 10.

[0036] The washer 24 can thus tilt or be inclined to self-align with the rotating machine that it supports. The rounded washer 24 in the bowl 22 provides a robust construction which enables the self-alignment, as opposed to e.g. pneumatic or hydraulic alignment systems. In examples, the washer 24 may be a spherical washer i.e., the curved bottom surface of the washer substantially corresponds to a part of a sphere. The upper surface of the bowl is complementary to this surface and thus may be substantially spherical as well.

[0037] The washer assembly 30 has a sliding top surface for contacting the rotating machine. In some examples, like in the example of figure 1 , the sliding top surface is included in a sliding plate 26 mounted to the top of the washer 24. The sliding plate may be bolted to the washer 24, e.g. countersunk holes in the sliding plate 26 may be used to attach the sliding element 26 to the washer.

[0038] The sliding plate 26 may have a coefficient of friction which promotes sliding of the rotating machine that is supported with respect to the sliding plate 26. In some examples, the sliding plate 26 may be a slide plate commercially available from Deva™. Such a sliding plate may be made of copper casting alloys with solid lubricant deposits of graphite or PTFE. Other materials may be used, and a suitable material and coefficient of friction may depend on the rotating machine that is supported by the leveling assembly.

[0039] The sliding plate 26 may be dimensioned as a function of the component or rotating machine it is to support. [0040] The leveling assembly 40 of the example of figure 1 further comprises a first lateral panel 12 for laterally closing the inner space 15 of the base block 10 at a first side, and comprises a second lateral panel 14 for laterally closing the inner space 15 of the base block 10 at a second side (opposite the first side) and for retaining the shim plates and the bowl in the inner space. The resulting inner space 15 is thus open at the top and the washer assembly 30 protrudes from the top.

[0041] In the illustrated example, the first lateral panel 12 and the second lateral panel 14 are configured for being removably connected to the base block 10 with bolts 16. In the example of figure 1 , each of the lateral panels 12, 14 is attached to the base block with two bolts 16 and washer rings 18. If at least one of the lateral panels is removably connected to the base block 10, such a lateral panel can be removed to add or remove shim plates, e.g. after an initial leveling. The lateral panel may then be reattached to retain the shim plates in the inner space.

[0042] The base block 10 in this example has two (bottom) flanges 9, and each of the flanges may have a tapped hole 7 for receiving bolts 34 for fixing the base block to a ground level or foundation. Suitable washer rings 36 may be provided as well.

[0043] The base block may be made of carbon steel in some examples. However other suitable materials that can support the weight of the (component of) the rotating machine and with sufficient thermal stability may be chosen. Also, the lateral panels 12, 14 may be made of carbon steel in some examples.

[0044] Figures 2A - 2C illustrate a further example of a leveling assembly 40. In many respects, the leveling assembly 40 of figure 2 is similar to the leveling assembly of figure 1. Like in figure 1 , the base block 10 comprises an inner space in which one or more shim plates 20 may be arranged. A washer assembly 30 is disposed on top of the shim plates 20. By stacking more or less shim plates, the washer assembly 30 can thus be elevated or lowered.

[0045] Like in figure 1 , the shim plates 20 are retained in the inner space 15 by lateral panels 12, 14. Both the lateral panels 12, 14 are removably connected through bolts. The lateral panels 12 comprise suitable bolt holes 13 which can be aligned with tapped holes 17 in the base block 10. The washer assembly 30 in this example also generally resembles the washer assembly of the example of figure 1 allowing tilting of the washer 24 with respect to the bowl 22, and thereby with respect to the base block 10. The concave upper surface 25 of the bowl 22 is shaped to be complementary to the convex bottom surface of the washer 24. [0046] In the example of figures 2A - 2C, the leveling assembly 40 further comprises a base plate 38, and the base block 10 is mounted on top of the base plate 38. In particular, the base block 10 may be welded on top of the base plate 38.

[0047] In examples, the base plate and/or the base block may be made of carbon steel, but other suitable materials may be chosen as well. The base plate 38 in this example may comprise one or more holes 44 for receiving bolts to attach the base plate to a ground level or foundation.

[0048] In some examples, the leveling assembly may comprise pre-leveling screws for a rough leveling of the assembly with respect to a ground level or foundation. More precise leveling may then be provided by adjustment of the number of shim plates as previously explained herein.

[0049] In a further aspect, a turbomachine is provided, which is supported by one or more leveling assemblies according to any of the examples disclosed herein. In examples, an existing leveling assembly may be substituted by one of the leveling assemblies described herein. In further examples all leveling assemblies supporting the turbomachine may be leveling assemblies according to the present disclosure.

[0050] The turbomachine may be connected to a foundation through a plurality of anchoring studs. In examples, one anchoring stud may be arranged with each of the leveling assemblies. In general, the anchoring studs may be arranged in the vicinity of the leveling assemblies.

[0051] The turbomachine may be a gas turbine. In a further aspect, the turbomachine may be a steam turbine. And in yet a further aspect, a fossil, renewable-energy, waste-to-energy, combined-cycle or nuclear powerplant comprising such a steam turbine is provided.

[0052] In a further aspect, the use of a leveling assembly according to any of the herein disclosed examples is provided. The use includes providing the leveling assembly and inserting one or more shim plates into the inner space of the base block, or removing one or more shim plates from the inner space of the base block.

[0053] In some examples, the leveling assembly may comprise a first lateral panel for laterally closing the inner space of the base block at a first side, and a second lateral panel for laterally closing the inner space of the base block at a second side and for retaining the shim plates and the bowl in the inner space. The use of the leveling assembly may further comprise, after the step of inserting said one or more shim plates, laterally closing the inner space by mounting of at least one of the first lateral panel and the second lateral panel to the base block. [0054] A preferred use of a leveling assembly for leveling of a rotating machine comprises providing the base block, with at least one of the lateral panels unmounted, but with the other lateral plane attached. That is, in this procedure, a single lateral panel may be mounted before positioning the leveling assembly underneath the rotating machine that it will support. Shim plates can be inserted laterally into the inner space of the base block. The sidewalls and lateral panel of the base block 10 retain the shim plates in position. Similarly, as needed, shim plates may be removed laterally from the inner space. After adjustment of the number of shim plates, the unmounted lateral panel may be attached to laterally close the inner space and firmly retain the shim plates and washer assembly.

[0055] In examples, before inserting or removing one or more shim plates, the rotating machine may be lifted, e.g. using one or more jacks. Any suitable jack may be used for this purpose, e.g. hydraulic jacks. After lifting the rotating machine, the leveling assembly may be positioned under the rotating machine.

[0056] In examples, after providing the desired number of shim plates, and after the step of laterally closing the inner space, the rotating machine may be lowered with the one or more jacks. Then, the one or more jacks may be removed.

[0057] This written description uses examples to disclose a teaching, including the preferred embodiments, and also to enable any person skilled in the art to put the teaching into practice, including making and using any devices or systems and performing any incorporated methods. The patentable scope is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. Aspects from the various embodiments described, as well as other known equivalents for each such aspects, can be mixed and matched by one of ordinary skill in the art to construct additional embodiments and techniques in accordance with principles of this application. In any case, elements of examples and embodiments as well as the whole embodiments and examples can be combined together in any order and number to produce new examples and embodiments that are within the scope of this disclosure. If reference signs related to drawings are placed in parentheses in a claim, they are solely for attempting to increase the intelligibility of the claim, and shall not be construed as limiting the scope of the claim.

Claims

1 . A leveling assembly for supporting a rotating machine, comprising: a base block defining an inner space for receiving one or more shim plates; and a washer assembly, wherein the washer assembly comprises a bowl and a washer supported by the bowl, wherein the bowl is configured for being received in the inner space and on top of the shim plates and wherein the bowl has a curved top surface, and the washer is configured for being received in the bowl, and has a curved bottom surface that is complementary to the curved top surface of the bowl such that the washer can tilt with respect to the bowl, and wherein the washer assembly further has a sliding top surface for supporting the rotating machine.

2. The leveling assembly according to claim 1 , further comprising: a first lateral panel for laterally closing the inner space of the base block at a first side, and a second lateral panel for laterally closing the inner space of the base block at a second side, and wherein the first lateral panel and the second lateral panel are configured for retaining the shim plates and the bowl in the inner space.

3. The leveling assembly according to claim 2, wherein the first lateral panel and/or the second lateral panel are configured for being removably connected to the base block.

4. The leveling assembly according to any of claims 1 - 3, further comprising a base plate, wherein the base block is mounted on the base plate.

5. The leveling assembly according to claim 4, wherein the base plate comprises one or more holes for receiving fasteners to mount the base plate to a foundation.

6. The leveling assembly according to claim 4 or 5, wherein the base plate and/or the base block are made of carbon steel.

7. The leveling assembly according to any of claims 1 - 6, wherein the sliding top surface is included in a sliding plate mounted to the top of the washer.

8. The leveling assembly according to any of claims 1 - 7, wherein the curved bottom surface of the washer substantially corresponds to a part of a sphere.

9. The leveling assembly according to any of claims 1 - 8, further comprising one or more pre-leveling screws for leveling of the assembly with respect to a ground level.

10. The leveling assembly according to any of claims 1 - 9, further comprising one or more one or more shim plates.

11. A turbomachine supported by one or more leveling assemblies according to any of claims 1 - 10.

12. The turbomachine according to claim 11 , wherein the turbomachine is a steam turbine or a gas turbine.

13. Use of a leveling assembly according to claim 1 - 10 for leveling of a rotating machine, wherein the leaving assembly comprises: a base block defining an inner space for receiving one or more shim plates; and a washer assembly, wherein the washer assembly comprises a bowl and a washer supported by the bowl, wherein the bowl is configured for being received in the inner space and on top of the shim plates and wherein the bowl has a curved top surface, and the washer is configured for being received in the bowl, and has a curved bottom surface that is complementary to the curved top surface of the bowl such that the washer can tilt with respect to the bowl, and wherein the washer assembly further has a sliding top surface for supporting the rotating machine, and wherein the use includes: inserting said one or more shim plates into the inner space of the base block, or removing said one or more shim plates from the inner space of the base block.

14. The use of claim 13, wherein the leveling assembly further comprises: a first lateral panel for laterally closing the inner space of the base block at a first side, and a second lateral panel for laterally closing the inner space of the base block at a second side and for retaining the shim plates and the bowl in the inner space, and wherein the use further comprises, after the step of inserting said one or more shim plates, laterally closing the inner space by mounting of at least one of the first lateral panel and the second lateral panel to the base block.

15. The use of claim 13-14 further comprising: before the step of inserting or removing said one or more shim plates, lifting the rotating machine with one or more jacks and positioning the leveling assembly under the rotating machine, and I or after the step of laterally closing the inner space, lowering the rotating machine with the one or more jacks and removing the one or more jacks.