JP5922809B1 - Tilting pad bearing and rotating machine - Google Patents

Abstract

Provided are a tilting pad bearing and a rotating machine capable of suppressing fretting wear occurring on a contact surface between a bearing pad and a pivot as the bearing pad swings. A tilting pad bearing is fitted to and fixed to at least one bearing pad and a first recess provided on an outer peripheral surface of the bearing pad, and the bottom surface of the first recess. A liner having an inner surface that contacts the entire surface, and an outer surface opposite to the inner surface of the liner, and supports the liner in a tiltable manner so that at least the center of curvature of the bearing pad is displaced. A pivot, and a carrier ring provided on the outer peripheral side of the bearing pad and having a second recess into which the pivot is fitted on the inner peripheral surface. A contact portion between the outer surface of the liner and the pivot is located inside the second recess. The bearing pad is configured to be prevented from rotating in a circumferential direction of the bearing surface of the bearing pad by fitting the liner into the second recess. [Selection] Figure 2

Description

  The present disclosure relates to a tilting pad bearing and a rotating machine including at least one bearing pad provided so as to be swingable about a pivot.

  In general, a tilting pad bearing is known as a kind of sliding bearing. The tilting pad bearing supports the rotating shaft by a plurality of bearing pads arranged in the circumferential direction of the rotating shaft. When the rotary shaft rotates, a wedge-shaped oil film is formed between each bearing pad and the rotary shaft, and lubricity between the rotary shaft and the bearing surface is ensured.

  For example, Patent Document 1 describes a tilting pad bearing used as a journal bearing. This tilting pad bearing has a configuration in which a spherical pivot is fitted into a concave portion formed on the inner peripheral side of a cylindrical bearing housing, and an adjustment liner is press-fitted into the concave portion formed on the outer peripheral side of the bearing pad. With this configuration, the bearing pad swings around the contact portion between the adjustment liner and the pivot.

JP 2010-116959 A

However, in the tilting pad bearing described above, the contact portion between the bearing pad (the adjustment liner in Patent Document 1) and the spherical pivot when the rotation shaft starts rotating and the bearing pad tilts or during rotation of the rotation shaft. Since the position of the bearing slightly changes, the contact surface between the bearing pad and the pivot may slide to cause fretting wear. Fretting wear becomes a factor that deteriorates the state of the contact surface of the bearing pad and the pivot. That is, as the sliding amount on the contact surface between the bearing pad and the pivot increases, the surface state of the contact surface deteriorates, and if the state continues for a long time, the tilting pad bearing may malfunction.
In this regard, Patent Document 1 does not disclose any specific measures for suppressing fretting wear occurring on the contact surface between the bearing pad and the pivot.

  In view of the above circumstances, at least one embodiment of the present invention provides a tilting pad bearing and a rotary machine that can suppress fretting wear occurring on the contact surface between the bearing pad and the pivot as the bearing pad swings. The purpose is to provide.

(1) A tilting pad bearing according to at least one embodiment of the present invention includes:
At least one bearing pad;
A liner having an inner surface that fits into a first recess provided on an outer peripheral surface of the bearing pad and is fixed to the bearing pad, and that contacts the entire bottom surface of the first recess;
A pivot that abuts the outer surface of the liner opposite to the inner surface and supports the liner in a tiltable manner so that at least the center of curvature of the bearing pad is displaced;
A carrier ring provided on the outer peripheral side of the bearing pad and having a second recess on the inner peripheral surface with which the pivot fits,
The contact portion between the outer surface of the liner and the pivot is located inside the second recess,
The bearing pad is configured to be prevented from rotating in a circumferential direction of the bearing surface of the bearing pad by fitting the liner into the second recess.

According to the tilting pad bearing of (1) above, the contact portion between the outer surface of the liner and the pivot is located inside the second recess formed in the carrier ring. The ratio of the sliding distance between the outer surface of the liner and the pivot with respect to the displacement amount of the center of curvature of the bearing pad is reduced, and fretting wear at the contact portion can be suppressed. That is, the distance d ₁ from the center of curvature of the bearing pad to the contact portion when the contact portion is located inside the second recess is equal to the bearing pad when the contact portion is located on the inner peripheral side of the carrier ring. It is longer than the distance d ₂ from the center of curvature to the abutment. Therefore, when the bearing pad is tilted by the same angle with the contact portion as a fulcrum, the displacement amount of the center of curvature of the bearing pad is larger at the distance d ₁ longer than the distance d ₂ . That is, when the displacement amount of the center of curvature of the bearing pads are the same, the direction of longer distance d ₁ than the distance d _2, the inclination angle of the bearing pads is small. The sliding distance between the contact portion between the outer surface and the pivot of the liner corresponds to the inclination angle of the bearing pads, the liner by increasing the distance d ₁ from the center of curvature of the bearing pads to the contact portion The sliding distance between the outer surface and the pivot can also be reduced, so that fretting wear can be suppressed.
In addition, since the liner is fitted to the first recess of the bearing pad and fixed to the bearing pad, the bearing pad is fitted in the second recess of the carrier ring so that the bearing pad is circumferential with respect to the carrier ring. It is designed to prevent rotation. For this reason, it can prevent that a bearing pad moves to the circumferential direction by rotation of a rotor. In addition, it is not necessary to provide a separate detent mechanism, and the bearing structure can be simplified.

(2) In some embodiments, in the configuration of (1) above,
The abutting surface of the pivot that abuts on the outer surface of the liner has an arc shape in cross section perpendicular to the center axis of the carrier ring.
According to the configuration of (2) above, the bearing pad and the liner that swing within the cross section perpendicular to the central axis of the carrier ring can be appropriately supported by the pivot.

(3) In some embodiments, in the above configuration (1) or (2),
When the circumferential width of the bearing surface of the bearing pad is W _pad1 and the circumferential width of the outer surface of the liner is W _L1 , 0.3W _pad1 ≦ W _L1 ≦ 0.5W _pad1 is satisfied.
(4) In some embodiments, in any one of the above configurations (1) to (3),
When the axial width of the bearing surface of the bearing pad is W _pad2 and the axial width of the outer surface of the liner is W _L2 , _{0.25W pad2} ≦ W _L2 ≦ 0.5W _pad2 is satisfied.
According to the configuration of (3) or (4) above, the rigidity of the liner can be improved. Therefore, by supporting the bearing pad that is to be deformed in a direction in which the curvature is reduced by the temperature rise caused by the rotation of the rotating shaft and the support load received from the pivot from the back side, the deformation of the bearing pad can be suppressed.

(5) In some embodiments, in any one of the above configurations (1) to (4),
When the circumferential width of the inner surface of the liner is W _L1 and the circumferential width of the contact surface of the pivot that contacts the outer surface of the liner is W _P1 , 0.5 W _P1 ≦ W _L1 ≦ 1 .1W _P1 is satisfied.
(6) In some embodiments, in any one of the above configurations (1) to (5),
When the axial width of the inner surface of the liner is W _L2 and the axial width of the contact surface of the pivot that contacts the outer surface of the liner is W _P2 , 0.5 W _P2 ≦ W _L2 ≦ 1 .1W _P2 is satisfied.

(7) In some embodiments, in any one of the configurations (1) to (6) above,
The liner thickness is greater than the pivot thickness.
According to the configuration of the above (7), since the rigidity of the liner can be improved, the bearing pad which is to be deformed in a direction in which the curvature is reduced by the temperature rise caused by the rotation of the rotating shaft and the support load received from the pivot is backed by the liner. By supporting from the side, deformation of the bearing pad can be suppressed. Further, as described in (1) above, since the contact portion between the outer surface of the liner and the pivot is located inside the second recess of the carrier ring, the thickness of the liner in the configuration of (7) is pivoted. It is easy to make it larger than the thickness.

(8) In some embodiments, in any one of the above configurations (1) to (7),
A gap is formed between the side wall surface of the second recess of the carrier ring and the side wall surface of the liner,
The liner can tilt with respect to the carrier ring by an amount corresponding to the size of the gap.
According to the configuration of (8), since the gap is formed between the side wall surface of the second recess of the carrier ring and the side wall surface of the liner, the liner can be freely prevented by preventing interference between the carrier ring and the liner. Can be tilted.

(9) A rotating machine according to at least one embodiment of the present invention includes:
The tilting pad bearing according to any one of (1) to (8) above;
And a rotating shaft supported by the tilting pad bearing.
According to the rotating machine of the above (9), a rotating machine having excellent durability can be provided by employing the tilting pad bearing capable of suppressing fretting wear at the contact portion between the outer surface of the liner and the pivot. .

  According to at least one embodiment of the present invention, the contact portion between the outer surface of the liner and the pivot is located inside the second recess formed in the carrier ring, so that the bearing pad and the liner are tilted so that the bearing pad is tilted. When the center of curvature is displaced, the sliding distance between the outer surface of the liner and the contact portion of the pivot is reduced, and fretting wear at the contact portion can be suppressed.

It is sectional drawing along the axial direction of the tilting pad bearing which concerns on some embodiment. It is the sectional view on the AA line of FIG. It is the elements on larger scale of the tilting pad bearing which concerns on one Embodiment. FIG. 4 is a sectional view taken along line BB in FIG. 3. It is the elements on larger scale of the tilting pad bearing which concerns on other embodiment. It is CC sectional view taken on the line of FIG. It is a schematic diagram for demonstrating fretting wear of a bearing pad.

  Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Absent.

First, an overall configuration common to the tilting pad bearing 10 according to some embodiments will be described with reference to FIGS. 1 and 2.
FIG. 1 is a cross-sectional view along the axial direction of a tilting pad bearing 10 according to an embodiment. 2 is a cross-sectional view taken along line AA in FIG. FIG. 2 is a cross section orthogonal to the axial direction. In the present embodiment, the axial direction is the direction of the central axis O of the rotating shaft (hereinafter referred to as the rotor) 2 supported by the tilting pad bearing 10, and the radial direction is the radial direction of the rotor 2. is there.

  The tilting pad bearing 10 shown in FIGS. 1 and 2 employs a direct lubrication method as a lubrication method (oil supply method), and has a configuration in which two bearing pads 30 and 32 are arranged in the lower half. ing. Hereinafter, the illustrated tilting pad bearing 10 will be described as an example, but the tilting pad bearing 10 according to the present embodiment is not limited to this configuration. For example, the tilting pad bearing according to another embodiment may employ an oil bath system or another lubrication system as a lubrication system. In addition, the tilting pad bearing according to another embodiment is not limited in the circumferential position, and may have at least one bearing pad. For example, two bearings are provided in the upper half and the lower half, respectively. The structure by which the pad is arrange | positioned may be sufficient.

In addition, as the rotary machine 1 to which the tilting pad bearing 10 according to the present embodiment is applied, for example, a turbine such as a gas turbine, a steam turbine, or a machine driving turbine, a wind machine such as a wind power generator, or a supercharger Etc.
Here, the rotating machine 1 includes a rotor 2 that is rotationally driven, a bearing housing (not shown) that houses the rotor 2, and a tilting pad bearing 10 that supports the rotor 2.

  In one embodiment, the tilting pad bearing 10 includes a carrier ring 11 attached to a bearing housing (not shown) of the rotating machine 1, and two bearing pads 30 and 32 disposed on the inner peripheral side of the carrier ring 11. The liner 36 is fixed to the bearing pads 30 and 32, and the pivot 38 supports the bearing pads 30 and 32 and the liner 36.

Hereinafter, a specific configuration example of each member of the tilting pad bearing 10 will be described.
The carrier ring 11 includes an upper half carrier ring 12 and a lower half carrier ring 13. The upper half carrier ring 12 and the lower half carrier ring 13 have inner circumferential surfaces 12a and 13a and outer circumferential surfaces 12b and 13b, respectively, such that the cross section perpendicular to the axial direction is a semicircular arc. In the illustrated example, the carrier ring 11 is divided into an upper half carrier ring 12 and a lower half carrier ring 13. However, the carrier ring 11 may be an integral structure.

Each of the upper half carrier ring 12 and the lower half carrier ring 13 is fixed in a circumferential position and an axial position by a fixing means with respect to a bearing housing (not shown).
Side plates 17 and 18 are disposed on both ends of the carrier ring 11 in the axial direction. The side plates 17 and 18 are formed in a disc shape, and holes 17a and 18a through which the rotor 2 passes are formed in the center. These side plates 17 and 18 suppress leakage of lubricating oil supplied from oil supply nozzles 25 to 29 described later to the outside.

  In the upper half carrier ring 12, guide metals 20 and 21 are attached to the inner peripheral surface 12a mainly to prevent the rotor 2 from jumping up. For example, the pair of guide metals 20 and 21 are attached to both end sides in the axial direction of the upper half carrier ring 12 and inside the side plates 17 and 18 in the axial direction. The guide metals 20 and 21 are formed in a semicircular shape.

  The upper half carrier ring 12 and the lower half carrier ring 13 are provided with at least one oil supply nozzle 25 to 29. In the example shown in FIG. 2, when the rotor 2 rotates clockwise as indicated by an arrow S in the drawing, the first oil supply nozzle 25, the second oil supply nozzle 26, and the third oil supply nozzle from the upstream side in the rotation direction of the rotor 2. 27, four oil supply nozzles 28 and five oil supply nozzles 29 are provided. The first oil supply nozzle 25 and the second oil supply nozzle 26 are arranged side by side in the circumferential direction on the upstream side of the bearing pad 30 located on the upstream side. A gap may be provided between the second oil supply nozzle 26 and the upstream end of the bearing pad 30. The third oil supply nozzle 27 and the fourth oil supply nozzle 28 are arranged side by side in the circumferential direction between the bearing pad 30 and the bearing pad 32 located on the downstream side of the bearing pad 30. A gap may be provided between the third oil supply nozzle 27 and the bearing pad 30 and between the fourth oil supply nozzle 28 and the bearing pad 32. The fifth oil supply nozzle 29 is disposed on the downstream side of the bearing pad 32. A gap may be provided between the fifth oil supply nozzle 29 and the bearing pad 32.

  A lubricating oil supply path (not shown) is formed inside the carrier ring 11. The lubricating oil supplied to the lubricating oil supply path is sent to each of the oil supply nozzles 25 to 29, and is ejected from the oil supply nozzles 25 to 29 in the vicinity of the bearing pads 30 and 32.

Next, the bearing pads 30 and 32 and the peripheral structure will be described in detail.
FIG. 3 is a partially enlarged view of the tilting pad bearing 10 according to the embodiment. 4 is a cross-sectional view taken along line BB in FIG. FIG. 5 is a partially enlarged view of a tilting pad bearing 10 according to another embodiment. 6 is a cross-sectional view taken along the line CC of FIG. 3 and 5 show the bearing pad 30 and its peripheral structure in the tilting pad bearing 10 viewed from the same direction as FIG. 3 to 6 illustrate the bearing pad 30 positioned on the upstream side, the bearing pad 32 positioned on the downstream side also has the same configuration.

  As shown in FIGS. 3 to 6, the bearing pad 30 has a bearing surface (inner peripheral surface) 30 a facing the rotor 2 and an outer peripheral surface 30 b facing the lower half carrier ring 13. Each of the bearing surface 30a and the outer peripheral surface 30b has a curved shape so as to have a curvature corresponding to the rotor 2 in the circumferential direction, and linear in the axial direction of the rotor 2 in the axial direction. Is formed. A first recess 34 is formed on the outer peripheral surface 30 b of the bearing pad 30 in a substantially central region of the bearing pad 30. The first recess 34 is provided on the downstream side of the center of the width of the bearing pad 30 in the circumferential direction, and may be provided in the center of the length of the bearing pad 30 in the axial direction. Moreover, the 1st recessed part 34 may be formed in the column shape.

The liner 36 has an inner surface 36 a that fits into the first recess 34 and is fixed to the bearing pad 30, and the entire surface contacts the bottom surface 34 a of the first recess 34. The liner 36 is formed in a shape corresponding to the first recess 34. For example, when the first recess 34 has a cylindrical shape with a flat bottom surface 34a, the liner 36 also has a cylindrical shape with a flat inner surface 36a. Thus, the inner surface 36a and the side wall surface 36c of the liner 36 are in contact with the bottom surface 34a and the side wall 34c of the first recess 34 without any gap.
Further, the thickness of the liner 36 is larger than the depth of the first recess 34. Therefore, the outer surface 36b of the liner 36 is separated from the outer peripheral surface 30b of the bearing pad 30 in a state where the liner 36 is fitted to the first recess 34 so that the inner surface 36a of the liner 36 contacts the bottom surface 34a of the first recess 34. Projects radially outward. The outer surface 36b of the liner 36 protruding from the outer peripheral surface 30b of the bearing pad 30 may be formed flat.

  The pivot 38 is provided on the outer peripheral side of the bearing pad 30 and is configured to fit into a second recess 19 formed on the inner peripheral surface 13 a of the lower half carrier ring 13. For example, the second recess 19 is formed in a columnar shape, and the pivot 38 is also formed in a substantially columnar shape. The fitting surface 38a of the pivot 38 located on the bottom surface 19a side of the second recess 19 may be formed flat. On the other hand, the abutting surface 38b of the pivot 38 positioned on the side facing the rotor 2 has an arcuate cross section perpendicular to the central axis of the carrier ring 11, and this abutting surface 38b is the outer surface 36b of the liner 36. It comes to contact with. For this reason, the bearing pad 30 and the liner 36 that swing within the cross section orthogonal to the axial direction of the carrier ring 11 can be appropriately supported by the pivot 38. In the example shown in the drawing, the pivot 38 has an arc shape in cross section perpendicular to the axial direction of the carrier ring 11 and an arc shape in cross section including the axial direction. That is, the pivot 38 is a spherical pivot having a spherical contact surface 38b. Therefore, the pivot of the bearing pad 30 in the axial direction can be appropriately supported by the pivot 38.

  With reference to FIGS. 1 to 6, in the tilting pad bearing 10 having the above-described configuration, when the rotor 2 is stopped, the bearing clearance between the upstream end portions of the bearing pads 30 and 32 and the outer peripheral surface of the rotor 2. The bearing clearance between the downstream end of the bearing pads 30 and 32 and the outer peripheral surface of the rotor 2 is maintained at a predetermined interval. When the rotation of the rotor 2 starts, the rotation of the rotor 2 causes the lubricating oil from the upstream end side to the bearing clearance between the bearing surface 30a of the bearing pad 30, 32 of the bearing pad 30, 32 and the outer peripheral surface of the rotor 2. Is drawn, and a wedge-shaped oil film is formed in the bearing clearance. At this time, since the bearing pads 30 and 32 and the liner 36 are inclined about the contact portion 37 with the pivot 38, the upstream side end portion of the bearing surface 30 a of the bearing pads 30 and 32 and the outer peripheral surface of the rotor 2 are arranged. The bearing clearance is larger than that at the time of stopping, and the bearing clearance between the downstream end of the bearing surface 30a of the bearing pads 30 and 32 and the outer peripheral surface of the rotor 2 is narrower than that at the time of stopping. The wedge-shaped oil film formed between the bearing surface 30a of the bearing pads 30 and 32 and the outer peripheral surface of the rotor 2 ensures lubricity between the bearing pads 30 and 32 and the rotor 2, and the rotor 2 is tilted. The pad bearing 10 is stably supported.

In the tilting pad bearing 10, the contact portion 37 between the outer surface 36 b of the liner 36 and the pivot 38 is located inside the second recess 19 of the lower half carrier ring 13.
As described above, since the contact portion 37 between the outer surface 36b of the liner 36 and the pivot 38 is located inside the second recess 19 formed in the lower half carrier ring 13, the bearing pad 30 and the liner 36 are tilted. The ratio of the sliding distance between the outer surface 36b of the liner 36 and the pivot 38 with respect to the displacement amount of the center of curvature of the bearing pad 30 is reduced, and fretting wear at the contact portion 37 can be suppressed. That is, as shown in FIG. 7 , the distance d ₁ from the center of curvature M ₁ of the bearing pad 30 to the contact portion 37 when the contact portion 37 is located inside the second recess 19 is larger than that of the carrier ring 11. When the contact part 37 is located on the inner peripheral side, the distance d ₂ is longer than the distance d ₂ from the center of curvature M ₁ of the bearing pad 30 to the contact part 37. The bearing pads 30 abutting portion 37 from the center of curvature M ₁ as a fulcrum when inclined by the same angle θ to the center of curvature M _2, towards the distance d ₂ longer distance d ₁ than is the heart in the curvature of the bearing pads 30 The amount of displacement increases. That is, when the displacement amount of the song in the ratio of mind bearing pads 30 are the same, direction of the distance d ₂ longer distance d ₁ than the inclination angle θ of the bearing pad 30 is small. The sliding distance between the contact portion 37 of the outer surface 36b and the pivot 38 of the liner 36 corresponds to the θ angle of inclination of the bearing pads 30, et al or heart in the curvature of the bearing pads 30 to the contact portion 37 sliding distance between the outer surface 36b and the pivot 38 of the liner 36 by increasing the distance d ₁ can also be reduced, thus possible to suppress the fretting wear. In FIG. 7, the bearing pad 30 ′, the liner 36 ′, and the contact portion 37 ′ show a state after tilting.

Further, the bearing pad 30 is configured to be prevented from rotating in the circumferential direction of the bearing surface 30 a of the bearing pad 30 by fitting the liner 36 into the second recess 19. That is, since the liner 36 is fitted to the first recess 34 of the bearing pad 30 and fixed to the bearing pad 30, the liner 36 is fitted to the second recess 19 of the carrier ring 11, so that the bearing pad 30. Is prevented from rotating with respect to the carrier ring 11 in the circumferential direction. Note that the circumferential direction of the bearing surface 30 a substantially coincides with the rotational direction S of the rotor 2.
Thereby, it can prevent that the bearing pad 30 moves to the circumferential direction (rotation direction S) by rotation of the rotor 2. FIG. In addition, it is not necessary to provide a separate detent mechanism, and the bearing structure can be simplified.

Returning to FIGS. 3 to 6, a gap may be formed between the side wall surface 19 c of the second recess 19 of the lower half carrier ring 13 and the side wall surface 36 c of the liner 36. In this case, the liner 36 can be tilted with respect to the lower half carrier ring 13 by an amount corresponding to the size of the gap.
According to this configuration, since the gap is formed between the side wall surface 19c of the second recess 19 of the lower half carrier ring 13 and the side wall surface 36c of the liner 36, the lower half carrier ring 13 and the liner 36 are Thus, the liner 36 can be freely tilted. When the bearing pad 30 rotates unintentionally in the circumferential direction, the side wall surface 19c of the second recess 19 and the side wall surface 36c of the liner 36 come into contact with each other so that the rotation of the bearing pad 30 is prevented. It may be configured.

In an embodiment, when the circumferential width of the bearing surface (inner circumferential surface) 30a of the bearing pad 30 is W _pad1 and the circumferential width of the outer surface 36b of the liner 36 is W _L1 , 0.3W _pad1 ≦ W _L1 ≦ 0.5W _pad1 is satisfied.
Further, when the axial width of the bearing surface (inner peripheral surface) 30a of the bearing pad 30 is W _pad2 and the axial width of the outer surface 36b of the liner 36 is W _L2 , 0.25 W _pad2 ≦ W _L2 ≦ 0. _Satisfies 5W _pad2 .
According to these configurations, the rigidity of the liner 36 can be improved. Therefore, the bearing pad 30 that is to be deformed in the direction in which the curvature is reduced by the temperature rise caused by the rotation of the rotor 2 and the support load received from the pivot 38 is supported from the back side by the liner 36, thereby suppressing the deformation of the bearing pad 30. it can.

Further, the thickness of the liner 36 may be larger than the thickness of the pivot 38.
According to this configuration, since the rigidity of the liner 36 can be improved, the bearing pad 30 that is to be deformed in a direction in which the curvature decreases due to the temperature rise caused by the rotation of the rotor 2 and the support load received from the pivot 38 is backed by the liner 36. By supporting from the side, deformation of the bearing pad 30 can be suppressed. Further, as described above, the contact portion 37 between the outer surface 36 b of the liner 36 and the pivot 38 is located inside the second recess 19 of the lower half carrier ring 13, so that the thickness of the liner 36 can be reduced. It is easy to enlarge compared to the thickness.

In some embodiments, when the circumferential width of the inner surface 36a of the liner 36 and _{W L1,} the circumferential width of the contact surface 38b of the pivot 38 abuts against the outer surface 36b of the liner 36 was set to _{W P1,} 0 .5W _P1 ≦ W _L1 ≦ 1.1W _P1 is satisfied.
Further, the axial width of the inner surface 36a of the liner 36 and _{W L2,} when the axial width of the contact surface 38b of the pivot 38 abuts against the outer surface 36b of the liner 36 was set to _{W P2,} 0.5W _P2 ≦ _{W L2} ≦ 1.1W _P2 is satisfied.
Hereinafter, each embodiment having the above configuration will be described.

The embodiment shown in FIGS. 3 and 4 shows a tilting pad bearing 10 used for a steam turbine provided in a nuclear power plant as an example.
In the example shown in FIG. 3, the circumferential width of the inner surface 36a of the liner 36 and _{W L1,} when the circumferential width of the contact surface 38b of the pivot 38 abuts against the outer surface 36b of the liner 36 was set to _{W P1,} 0 .9W _P1 ≦ W _L1 ≦ 1.1W _P1 is satisfied.
In the example shown in FIG. 4, the axial width of the inner surface 36a of the liner 36 and _{W L2,} when the axial width of the contact surface 38b of the pivot 38 abuts against the outer surface 36b of the liner 36 was set to _{W P2,} 0 .9W _P2 ≦ W _L2 ≦ 1.1W _P2 is satisfied.
In the example shown, the inner surface 36a of the liner 36 and the circumferential width _{W L1,} the circumferential width _{W P1} of the contact surface 38b is substantially coincident pivot 38, and, the inner surface 36a of the liner 36 the axial width _{W L2,} the axial width _{W P2} of the contact surface 38b of the pivot 38 are substantially coincident. In this case, in the second recess 19, the diameter of the portion where the pivot 38 is fitted is substantially the same as the diameter of the portion where the liner 36 is located, and no step is provided on the side wall surface 19 c of the second recess 19. .

The other embodiments shown in FIGS. 5 and 6 show a tilting pad bearing 10 used in a gas turbine as an example.
In the example shown in FIG. 5, the circumferential width of the inner surface 36a of the liner 36 and _{W L1,} when the circumferential width of the contact surface 38b of the pivot 38 abuts against the outer surface 36b of the liner 36 was set to _{W P1,} 0 .5W _P1 ≦ W _L1 ≦ 0.7W _P1 is satisfied.
In the example shown in FIG. 6, the axial width of the inner surface 36a of the liner 36 and _{W L2,} when the axial width of the contact surface 38b of the pivot 38 abuts against the outer surface 36b of the liner 36 was set to _{W P2,} 0 .5W _P2 ≦ W _L2 ≦ 0.7W _P2 is satisfied.
In the example illustrated, towards the circumferential width _{W L1} of the inner surface 36a of the liner 36 is greater than the circumferential width _{W P1} of the contact surface 38b of the pivot 38, and, the inner surface 36a of the liner 36 towards the axial width _{W L2} it is greater than the axial width _{W P2} of the contact surface 38b of the pivot 38. Therefore, the second recess 19 is formed so that the diameter of the portion where the liner 36 is located is larger than the diameter of the portion where the pivot 38 is fitted. In other words, the second recess 19 includes a side wall surface 19c into which the pivot 38 is fitted, and a side wall surface 19d extending from the side wall surface 19c through a step.

  As described above, according to the embodiment of the present invention, the outer surface 36b of the liner 36 and the pivot 38 are brought into contact with the inner side of the second recess 19 formed in the carrier ring 11 (lower half carrier ring 13). Since the portion 37 is positioned, when the bearing pads 30 and 32 and the liner 36 are tilted and the centers of curvature of the bearing pads 30 and 32 are displaced, the sliding between the outer surface 36b of the liner 36 and the abutment portion 37 between the pivot 38 is avoided. A moving distance becomes small and the fretting wear in the contact part 37 can be suppressed.

  The present invention is not limited to the above-described embodiments, and includes forms obtained by modifying the above-described embodiments and forms obtained by appropriately combining these forms.

For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expression “comprising”, “including”, or “having” one constituent element is not an exclusive expression that excludes the presence of the other constituent elements.

1 Rotating machine 2 Rotor (Rotating shaft)
DESCRIPTION OF SYMBOLS 10 Tilting pad bearing 11 Carrier ring 12 Upper half carrier ring 13 Lower half carrier ring 17, 18 Side plate 19 2nd recessed part 20, 21 Guide metal 25-29 Oil supply nozzle 30, 32 Bearing pad 30a Inner peripheral surface 30b Outer periphery Surface 34 First recess 36 Liner 37 Contact portion 38 Pivot 38b Contact surface

Claims (8)

At least one bearing pad;
A liner having an inner surface that fits into a first recess provided on an outer peripheral surface of the bearing pad and is fixed to the bearing pad, and that contacts the entire bottom surface of the first recess;
A pivot that abuts the outer surface of the liner opposite to the inner surface and supports the liner in a tiltable manner so that at least the center of curvature of the bearing pad is displaced;
A carrier ring provided on the outer peripheral side of the bearing pad and having a second recess on the inner peripheral surface with which the pivot fits,
The contact portion between the outer surface of the liner and the pivot is located inside the second recess,
The bearing pad is configured to be prevented from rotating in a circumferential direction of the bearing surface of the bearing pad by fitting the liner into the second recess .
The side wall surface of the second recess of the carrier ring and the side wall surface of the liner are opposed to each other with a gap between them,
The tilting pad bearing according to claim 1, wherein the liner is tiltable with respect to the carrier ring by an amount corresponding to the size of the gap .   2. The tilting pad bearing according to claim 1, wherein an abutting surface of the pivot that abuts on the outer surface of the liner has an arc shape in cross section perpendicular to a center axis of the carrier ring. When the circumferential width of the bearing surface of the bearing pad is W _pad1 and the circumferential width of the outer surface of the liner is W _L1 , 0.3W _pad1 ≦ W _L1 ≦ 0.5W _pad1 is satisfied. The tilting pad bearing according to claim 1 or 2. When the axial width of the bearing surface of the bearing pad is W _pad2 and the axial width of the outer surface of the liner is W _L2 , _{0.25W pad2} ≦ W _L2 ≦ 0.5W _pad2 is satisfied. The tilting pad bearing according to any one of claims 1 to 3. When the circumferential width of the inner surface of the liner is W _L1 and the circumferential width of the contact surface of the pivot that contacts the outer surface of the liner is W _P1 , 0.5 W _P1 ≦ W _L1 ≦ 1 5. The tilting pad bearing according to claim 1, wherein the tilting pad bearing satisfies ₁ W _P1 . When the axial width of the inner surface of the liner is W _L2 and the axial width of the contact surface of the pivot that contacts the outer surface of the liner is W _P2 , 0.5 W _P2 ≦ W _L2 ≦ 1 The tilting pad bearing according to claim 1, wherein the tilting pad bearing satisfies 1 W _P2 .   The tilting pad bearing according to claim 1, wherein a thickness of the liner is larger than a thickness of the pivot. The tilting pad bearing according to any one of claims 1 to 7 ,
A rotating shaft supported by the tilting pad bearing.

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