DE102014119690A1 - Frequency tuning devices for torsional vibrations of a rotor strand - Google Patents

Abstract

There is provided a frequency tuning apparatus for torsional vibrations of a rotor string and includes first and second shafts, a clutch operatively disposed between the first and second shafts, and a coupling member disposed on the clutch and for adjusting a frequency of the first and second shafts and the clutch containing rotor strand is set up by a change in at least one of inertia and / or rotational stiffness in the rotor strand.

Description

BACKGROUND OF THE INVENTION

The subject matter of the invention described here is a frequency tuning device for torsional vibrations of a rotor strand and in particular a frequency tuning device for torsional vibrations of a rotor strand in which a rotor strand frequency can be adjusted by a change in mass inertia and / or rotational stiffness anywhere in the strand.

Rotating bodies, such as e.g. Rotors are used in many different types of mechanical and electrical elements, including generators, motors and other similar devices. These rotating bodies have multiple torsional natural vibration modes, and for a number of reasons, including stress, fatigue, performance, etc., it is desirable to keep these frequency modes outside certain operating ranges. For example, generators or other rotating body containing mechanical elements typically have at least one torsional natural frequency mode in the vicinity of a double mains frequency. If this frequency comes too close to a double mains frequency and is energized, it can cause a failure of elements in a coupled body, such as e.g. cause the blades of the last stage, in a turbine coupled thereto.

A frequency of a rotor torsional vibration mode may be shifted by variations in either mass inertia or torsional stiffness which directly affect the frequency of the rotating body mode of interest (e.g., by adding or removing large shrink rings). However, making such changes requires a process of decoupling the rotor from other sections in the string and exposing the rotor to allow installation / removal of the rings. The rings are often very large, high strength and expensive, and if the process is unsuccessful, components may need to be machined to eliminate stiffness or inertia depending on the scenario. Each of these steps can be expensive and time consuming.

The above-described processes for tuning the frequency of a rotor torsional vibration mode also tend to target not only the torsional vibration frequency or vibration of the rotor modes. Rather, the current mass addition processes can affect the loads in the rotor and lead to undesirable lateral frequency variations.

BRIEF DESCRIPTION OF THE INVENTION

According to one aspect of the invention, there is provided a rotor-frequency torsional frequency tuning apparatus and includes first and second shafts, a clutch operatively disposed between the first and second shafts, and a clutch member disposed on the clutch and adjusting a frequency of the first and second Shaft and the coupling-containing rotor strand is set up by a change in at least one of inertia and / or rotational stiffness in the rotor strand.

The coupling element may have a variable mass.

The coupling element of each device mentioned above may have a repositionable mass.

Each apparatus mentioned above may further comprise: a stationary member disposed directly on the coupling member; and a portable mass that can be supported on the stationary element or the coupling element.

The coupling element of each device mentioned above may be at least one of a mechanically coupled to the coupling, shrunk onto the coupling and integrally formed with the coupling and wherein the portable mass comprises a ring plate.

According to another aspect, there is provided a rotor vibration frequency tuning apparatus and includes a coupling member fixedly mounted on a coupling operatively disposed between the first and second shafts and a portable mass that can be mounted on the coupling member in a supported manner. The portable mass is movable toward the coupling member to adjust at least one of torsional stiffness and rotational inertia of one of the shafts such that a frequency of a torsional vibration mode of one of the shafts is substantially identical to a natural frequency of the torsional vibration mode of the other shaft.

The frequency tuning device for torsional vibrations of a rotor string may include: a coupling member fixedly mounted on a coupling operatively disposed between the first and second shafts; and a portable mass, which can be supported on the coupling element, wherein the portable mass is movable towards the coupling element to at least one of a rotational stiffness and a Change rotational inertia of the second shaft such that a frequency of a torsional vibration mode of the second shaft is substantially identical to a natural frequency of the torsional vibration mode of the first shaft.

The coupling element of each device mentioned above may be at least one which is mechanically coupled to the coupling which is pressed onto the coupling and which is formed in one piece with the coupling.

The portable mass of each device mentioned above may comprise a ring plate.

In yet another aspect, a frequency tuning apparatus for torsional vibrations of a rotor string is provided. The rotor strand includes a coupling by means of which corresponding ends of shafts are connectable to each other. The device includes a fixedly arranged on the clutch coupling element and a portable mass, which can be arranged supported on the coupling element. The portable mass is slidable toward the coupling member to adjust at least one of torsional stiffness and rotational inertia of one of the shafts such that a frequency of a torsional vibration mode of one of the shafts is substantially identical to a natural frequency of the torsional vibration mode of the other shaft.

The shafts of the aforementioned apparatus may include: a first shaft coupled to a turbomachine; and a second shaft coupled to the first shaft via the clutch.

The coupling may include: a first coupling part associated with the end of the first shaft; and a second coupling part associated with the end of the second shaft,
wherein the coupling element is fixedly arranged on the second coupling part.

The coupling element may be mechanically coupled to the coupling.

The coupling element may comprise: a base ring mechanically coupled to the coupling; and a retaining ring extending axially from the base ring, wherein an outer radial surface of the coupling element, an axial surface of the base ring and an inner radial surface of the retaining ring define a ring, the portable mass having a ring plate sized to fit the ring in the ring is.

The rotor string may include a stationary member disposed directly on the coupling member, wherein the portable mass may be supported on the portable member or the coupling member and may be moved from one to the other of the stationary member and the coupling member.

The coupling element may be pressed onto the coupling in a press fit.

The coupling element may comprise a base ring shrunk onto the coupling, the base ring including an axial portion and a radial portion, wherein an outer radial surface of the axial portion and an axial surface of the radial portion define a pocket.

The portable mass may include a ring plate dimensioned to fit in the pocket.

The coupling element may be formed in one piece with the coupling.

The coupling element may comprise: a first coupling part associated with the end of the first shaft, a second coupling part associated with the end of the second shaft, an axial surface of the first coupling part, an axial surface of the second coupling part and a radial surface of the second coupling part defining a recess.

The portable mass has a ring plate, which is designed for screwing into the recess.

These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject of the invention considered as the invention is particularly shown in the claims at the end of the patent and clearly claimed. The above and other objects, features and advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

1 a schematic side view of a rotor strand is;

2 a schematic representation of a frequency tuning device for torsional vibrations of a rotor strand according to embodiments;

3 a schematic representation of a Frequenzabstimmvorrichtung for torsional vibrations a rotor string according to alternative embodiments;

4 is a schematic representation of a frequency tuning device for torsional vibrations of a rotor strand according to further alternative embodiments;

5 an axial view of multi-part plates or rings, which in the embodiments at least the 2 and 4 are usable; and

5 is a flowchart of a frequency tuning device for torsional vibrations of a rotor strand according to further alternative embodiments.

The detailed description explains embodiments of the invention together with advantages and features by way of example with reference to the drawings.

DETAILED DESCRIPTION OF THE INVENTION

The description given below relates to the tuning of internal torsional vibration frequencies, for example in turbine / generator drive trains. The description of such a vote is similar to the description in the U.S. Patent No. 8,013,481 the contents of which are incorporated herein by reference. The tuning can be applied to a coupling of two shafts or rotors and is provided by a torsional vibration absorber which serves to adjust a rotor strand frequency by variation in mass inertia and / or torsional rigidity anywhere in the strand.

According to 1 is a rotating body 100 with a mechanical device 102 over a first wave 105 connected. The rotating body 100 may be a generator rotor, but it will be understood that any mechanical element may be used in connection with embodiments of this invention. The mechanical device 102 can be any device that works with the rotating body 100 connected, such as a steam turbine, gas turbine, combined gas and steam turbine, etc. The first wave 105 has an end section 106 and is further at the end portion 106 with a complementary end section 107 a second wave 108 by means of a coupling 109 coupled or otherwise connected. As shown in 1 can the rotating body 100 , the first wave 105 and the second wave 108 by any suitable means including bearings 104 be stored.

The coupling 109 may be a first coupling part 1091 included, which is the end of the first wave 105 is assigned, and a second coupling part 1092 , which is the end of the second wave 108 assigned. The first end 105 , the second wave 108 and the first and second coupling parts 1091 and 1092 the clutch 109 from 1 form a section of a rotor strand 110 , According to the 2 - 4 becomes a frequency tuning device 1 provided for torsional vibrations of a rotor strand and is connected to the rotor strand 110 or usable with similar transmission facilities. As shown in 2 - 4 contains the device 1 a coupling element 2 , a stationary element 3 and a portable mass 4 , The coupling element 2 is firmly on the second coupling part 1092 the clutch 109 arranged. The stationary element 2 is in close proximity to the coupling element 2 arranged. The portable mass 4 can be supported either on the stationary element 3 or the coupling element 2 to be ordered.

As will be described in more detail below, the portable mass 4 from one of the stationary element 3 and the coupling element 2 to the other of the stationary element 3 and the coupling element 2 repositioned or displaced to at least one of a rotational stiffness and a rotational inertia of one of the first shaft 105 and the second wave 108 adjust. In particular, the portable mass 4 from the stationary element 3 to the coupling element 2 or from the coupling element 2 to the stationary element 3 be shifted to at least one of a rotational stiffness and a rotational inertia of the second shaft 108 adjust. Thereby, a frequency of a torsional vibration mode of the second shaft 108 substantially identical to a natural frequency of the torsional vibration mode of the first shaft 105 be made.

According to special reference to 2 can the coupling element 2 mechanically with the coupling 109 be coupled. In this case, contains the coupling element 2 a base ring 10 , which mechanically with an outer radial surface 11 the clutch 109 coupled, and a retaining ring 12 which is axially out of the base ring 10 extends. As shown in 2 define the outer radial surface 11 of the coupling element 109 , an axial surface 13 of the base ring 10 and an inner radial surface 14 of the retaining ring 12 in cooperation a ring 15 ,

In the arrangement described above, the stationary element contains 3 a flange 16 and hook elements 17 , The flange 16 is close to the coupling element 2 arranged and hook elements 17 are on the flange 16 to the Support or keep the portable mass 4 arranged in groups. Where the portable mass 4 as an annular inertia plate 18 or ring is provided, the portable mass 4 from the hook element 17 removed and on the coupling element 2 getting charged. According to embodiments, the portable mass 4 be provided as a complete annular element or as a plurality of composite circumferentially segmented parts and dimensioned so that they are in the ring 15 fits.

The loading can be the transport of the portable mass 4 from the flange 16 and the hook element 17 to the coupling element 2 and then moving the portable mass 4 in the ring 15 include. Such loading can be done without separation of the second shaft 108 from the first wave 105 without separation of the first wave 105 from the mechanical device 102 or the rotating body 100 and without separation of the second wave 108 from any downstream body on which the second shaft 108 can be attached.

According to further embodiments, the portable mass 4 as several portable masses 4 be provided, each containing similar or unique individual masses or weights. Thus, a customizable accuracy and precision of adjustment of at least one of the rotational stiffness and the rotational inertia of the second shaft 108 be achieved by one or more portable masses 4 in the ring 15 getting charged.

During operation of the rotor train 110 from 2 drives a rotation of the first shaft 105 a corresponding rotation of the second shaft 108 and the portable mass (or masses) 4 at. The portable mass (or masses) 4 are thus by the retaining ring 12 and by between the portable mass (or masses) 4 and the inner radial surface 14 held the retaining ring generated centrifugal forces. An additional inclusion of the portable mass (or masses) 4 can be provided by fasteners which are optional for attaching or screwing the portable mass (or masses) 4 on the base ring 10 are provided.

Referring specifically to 3 can the coupling element 2 on the clutch 109 be pressed on. In this case, contains the coupling element 2 a base ring 20 which is for a shrink fit on an outer radial surface 21 the clutch 109 is designed, and which an axial section 22 and a radial section 23 contains. As shown in 3 can have an outer radial surface 24 of the axial section 22 and an axial surface 25 of the radial section 23 together an annular bag 26 define.

In the arrangement described above, the stationary element includes an end face 27 , which directly on the coupling element 2 arranged and for supporting or holding the portable mass 4 is designed. Where the portable mass 4 as an annular inertia plate 28 or ring is provided, the portable mass of the end face 27 be removed and on the coupling element 2 getting charged. According to embodiments, the portable mass 4 be provided as a complete annular element or as a plurality of circumferentially segmented pieces, which are assembled and suitable for the bag 26 are dimensioned.

The loading can be the transfer of the portable mass 4 from the frontal area 27 to the coupling element 2 and then the displacement of the portable mass 4 in the pocket 26 include. Such loading can be done without separation of the second shaft 108 from the first wave 105 , without separation of the first wave 105 from the mechanical device 102 or the rotating body 100 and without separation of the second wave 108 from any downstream body to which the second wave 108 can be fixed, carried out.

According to further embodiments, the portable mass 4 as several portable masses 4 be provided, each containing similar or unique individual masses or weights. Thus, a customizable accuracy and precision of adjustment of at least one of the rotational stiffness and the rotational inertia of the second shaft 108 be achieved by one or more portable masses 4 in the pocket 26 getting charged.

During operation of the rotor train 110 from 3 drives a rotation of the first shaft 105 a corresponding rotation of the second shaft 108 and the portable mass (or masses) 4 at. The portable mass (or masses) 4 are thus by axial section 22 and by between the portable mass (or masses) 4 and the outer radial surface 24 of the axial section 22 generated centrifugal forces in the bag 24 held. An additional inclusion of the portable mass (or masses) 4 can be provided by fasteners which are optional for attaching or screwing the portable mass (or masses) 4 at the radial portion 23 are provided.

Referring specifically to 4 can the coupling element 2 in one piece with the clutch 109 be educated. In this case contains the coupling element 2 the first coupling part 1091 and the second coupling part 1092 (please refer 1 and 4 ). As shown in 4 define an axial surface 30 of the first coupling part 1091 , an axial surface 31 of the second coupling part 1092 and a radial surface 32 of the second coupling part 1092 cooperatively an annular recess 33 ,

In the arrangement described above, the stationary element contains 3 a flange 34 and hook elements 35 , The flange 34 is directly on the coupling element 2 arranged and the hook elements 35 are on the flange 34 in groups for supporting or holding the portable mass 4 arranged. Where the portable mass 4 as an annular inertia plate 36 or ring is provided, the portable mass 4 from the hook elements 35 be lifted and on the coupling element 2 getting charged. According to embodiments, the portable mass 4 be provided as a complete annular member or as a plurality of circumferentially segmented pieces which are assembled and suitable for the recess 33 are dimensioned.

The loading can be the transfer of the portable mass 4 from the flange 34 and the hook elements 35 to the coupling element 2 and then the displacement of the portable mass 4 in the recess 33 include. Such loading can be done without separation of the second shaft 108 from the first wave 105 , without separation of the first wave 105 from the mechanical device 102 or the rotating body 100 and without separation of the second wave 108 from any downstream body to which the second wave 108 can be fixed, carried out.

According to further embodiments, the portable mass 4 as several portable masses 4 be provided, each containing similar or unique individual masses or weights. Thus, a customizable accuracy and precision of adjustment of at least one of the rotational stiffness and the rotational inertia of the second shaft 108 be achieved by one or more portable masses 4 in the ring 15 getting charged.

During operation of the rotor train 110 from 4 drives a rotation of the first shaft 105 a corresponding rotation of the second shaft 108 and the portable mass (or masses) 4 at. The portable mass (or masses) 4 become thus by between the portable mass (or masses) 4 and the axial surface 31 of the second coupling part 1092 generated centrifugal forces held in the recess. An additional inclusion of the portable mass (or masses) 4 can be provided by fasteners which are optional for attaching or screwing the portable mass (or masses) 4 on the second coupling part 1092 are provided.

According to further embodiments and with reference to 5 it is understood that at least the inertia plates 18 the embodiments of 2 and the inertia plates 36 the embodiments of 4 in several pieces, such as the segments 50 and 51 from 5 , can be provided. These segments are along the edge 52 Can be fastened together and can be used for easier installation of the portable mass 4 in each of the relevant cases. Additionally, the use of the segments 50 and 51 , the decrease or absence of the stationary element 3 of or in the embodiments at least the 2 and 4 allow or allow. In these cases, the segments could 50 and 51 each in the immediate vicinity of the coupling element 2 and separated from the clutch 109 stowed or held. As soon as such an arrangement occurs, the segments 50 and 51 assembled and otherwise connected to the inertia plate 18 in the ring 15 (please refer 2 ) or in the recess 33 (please refer 4 ) train.

With reference to 6 For example, there is provided a frequency tuning apparatus for torsional vibrations of a rotor string according to further alternative embodiments. As in 6 shown, is the coupling element 2 at the clutch 109 arranged as described above and is provided as a variable mass. Thus, all or part of the mass of the coupling element 2 be moved, extended or stretched along axial or radial dimensions according to desire or need to at least one of the torsional rigidity and the rotational inertia of the second shaft 108 adjust. According to embodiments, the variable mass may comprise a shape changing or smart material, such as a shape memory alloy (eg, nickel-titanium alloy) or a shape memory polymer. In these cases, a design of the coupling element 2 be changed by applying heat or electricity.

The above-described embodiments added torsional vibration inertia over or between the clutch 109 in the rotor strand 110 added. This change in the mass inertia gives a torsional natural frequency of the vibration in the second shaft 108 substantially identical to the rotational vibration frequency of interest in the first wave 105 is complete, and using modifications assembled unit is achieved. In addition, since the modifications are made to a fully assembled unit, the modifications allow for result verification and further modifications if necessary.

Although the invention has been described in detail only in connection with a limited number of embodiments, it should be readily understood that the invention is not limited to such described embodiments. Rather, the invention may be modified to include any number of variations, changes, substitutions, or equivalent arrangements not heretofore described, which are within the spirit and scope of the invention. In addition, while various embodiments of the invention have been described, it should be understood that aspects of the invention may be included within only some of the described embodiments. Accordingly, the invention should not be considered as limited by the description, but is limited only by the scope of the appended claims.

There is provided a frequency tuning apparatus for torsional vibrations of a rotor string and includes first and second shafts, a clutch operatively disposed between the first and second shafts, and a coupling member disposed on the clutch and for adjusting a frequency of the first and second shafts and the clutch containing rotor strand is set up by a change in at least one of inertia and / or rotational stiffness in the rotor strand.

LIST OF REFERENCE NUMBERS

100

 rotating body

102

 mechanical device

105

 first wave

104

 camp

106

 end

107

 complementary end section

108

 second wave

109

 clutch

1091

 first coupling part

1092

 second coupling part

110

 rotor strand

1

 contraption

2

 coupling member

3

 stationary element

4

 portable mass

10

 base ring

11

 outer radial surface

12

 retaining ring

13

 axial surface

14

 inner radial surface

15

 ring

16

 flange

17

 hook elements

18

 inertia plates

20

 base ring

21

 outer radial surface

22

 axial section

23

 radial section

24

 outer radial surface

25

 axial surface

26

 annular bag

27

 face

28

 Inertia plate

30

 axial surface

31

 axial surface

32

 radial surface

33

 annular recess

34

 flange

35

 hook elements

36

 Inertia plate

50, 51

 segments

52

 edge

40

 changeable mass

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US8013481 [0035]

Claims (10)

Frequency tuning device for torsional vibrations of a rotor train, comprising: a first and second shaft; a clutch operatively disposed between the first and second shafts; and a coupling member disposed on the coupling and configured to adjust a frequency of a rotor string including the first and second shafts and the coupling by a variation in at least one of inertia and / or torsional stiffness in the rotor strand. The device of claim 1, wherein the coupling element comprises a variable mass; and / or wherein the coupling element has a repositionable mass. The device of claim 1, further comprising: a stationary element disposed directly on the coupling element; and a portable mass that can be supported on the stationary element or the coupling element can be arranged. Apparatus according to claim 3, wherein the coupling element is at least one of a mechanically coupled to the coupling, shrunk onto the coupling and formed in one piece with the coupling and wherein the portable mass comprises a ring plate. Frequency tuning device for torsional vibrations of a rotor train, comprising: a coupling member fixedly mounted on a coupling operatively disposed between first and second shafts; and a portable mass that can be mounted on the coupling element, wherein the portable mass is movable toward the coupling member to adjust at least one of torsional stiffness and rotational inertia of one of the shafts such that a frequency of a torsional vibration mode of one of the shafts is substantially identical to a natural frequency of the torsional vibration mode of the other shaft. Apparatus according to claim 5, wherein the coupling element is at least one of a mechanically coupled to the coupling, pressed onto the coupling and formed in one piece with the coupling. The device of claim 6, wherein the portable mass comprises a ring plate. Device for tuning the frequency of a torsional vibration mode of a rotor strand, wherein the rotor strand comprises: a coupling by means of which corresponding ends of shafts are connectable to each other, the device comprising: a fixedly arranged on the coupling coupling element; and a portable mass that can be supported on the coupling element, wherein the portable mass is slidable toward the coupling member to adjust at least one of torsional stiffness and rotational inertia of one of the shafts such that a frequency of a torsional vibration mode of one of the shafts is substantially identical to a natural frequency of the torsional vibration mode of the other shaft. Apparatus according to claim 8, wherein the corrugations comprise: a first shaft coupled to a turbomachine; and a second shaft coupled to the first shaft by means of the clutch, the clutch comprising: a first coupling part associated with the end of the first shaft; and a second coupling part associated with the end of the second shaft, wherein the coupling element is fixedly arranged on the second coupling part or mechanically coupled to the coupling. The device of claim 9, wherein the coupling element comprises: a base ring mechanically coupled to the clutch; and an axially extending from the base ring retaining ring, wherein an outer radial surface of the coupling element, an axial surface of the base ring and an inner radial surface of the retaining ring define a ring, wherein the portable mass comprises a ring plate sized to fit the ring in the ring.

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