JP2015200389A - Thrust bearing and rotary machine including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently cool bearing pads in a thrust bearing.SOLUTION: A thrust bearing includes: multiple bearing pads 20 which are provided spaced away from each other in a rotation direction R of a rotary shaft body 121 so as to slidably contact with a thrust collar in an axial direction; first nozzles 30, each of which is provided between the adjacent bearing pads 20 and jets a lubrication oil to the thrust collar, and second nozzles 40, each of which is provided adjacent to the first nozzle 30 between the adjacent bearing pads 20 and jets a fluid so that the flow of the fluid inclines to the outer side in a radial direction D as the fluid approaches the thrust collar.

Description

  The present invention relates to a thrust bearing and a rotary machine including the thrust bearing.

  In a rotating machine having a rotating shaft such as a steam turbine, a gas turbine, a pump, or an engine, a bearing device is used to rotatably support the rotating shaft. As such a bearing device, there are a journal bearing and a thrust bearing provided with a bearing pad having a pad surface slidably contacting a rotating shaft. In a bearing device including these bearing pads, lubricating oil flows between the pad surface of the bearing pad and the rotating shaft in order to enable safe operation of the rotating machine. An oil film is formed between the pad surface and the rotating shaft by the lubricating oil, and the bearing device supports the rotating shaft through the oil film.

  This lubricating oil also has an action of cooling heat generated on the pad surface by exchanging heat with the pad surface. However, the lubricating oil after cooling one bearing pad flows into the gap between the pad surface of the bearing pad adjacent to the bearing pad and the rotating shaft at a high temperature as carryover oil. When carry-over oil, which is a high-temperature lubricating oil, flows into the adjacent bearing pad, the bearing pad cannot be sufficiently cooled, resulting in a decrease in the oil viscosity of the lubricating oil and an increase in the thermal deformation of the bearing pad. Lubrication will deteriorate.

  Therefore, in the bearing device, a structure for efficiently cooling the bearing pad is used. For example, Patent Document 1 discloses a structure for reducing carryover oil flowing into an adjacent bearing pad in a journal bearing. Specifically, this journal bearing is provided with a seal fin that changes the flow direction of carryover oil to the outer side in the radial direction of the rotating shaft at an oiling nozzle disposed on the front side in the rotating direction of the rotating shaft with respect to the bearing pad. Provided. With this seal fin, it is possible to change the flow direction of the carryover oil flowing on the bearing pad side away from the outer peripheral surface of the rotating shaft out of the lubricating oil flowing in the gap between the bearing pad and the rotating shaft. Thereby, this journal bearing can efficiently reduce the flow rate of carryover oil flowing into the adjacent bearing pad.

JP 2000-274432 A

  By the way, unlike the journal bearing, the thrust bearing supports the thrust collar of the rotating shaft in the axial direction of the rotating shaft. Therefore, in the thrust bearing, the lubricating oil flows between the bearing pad and the thrust collar without approaching the bearing pad side.

  However, when the seal fin as described above is used, the carryover oil flowing along the outer peripheral surface of the rotating shaft can be changed even though the flow direction of the carryover oil flowing on the bearing pad side away from the outer peripheral surface of the rotating shaft can be changed. Cannot be eliminated sufficiently. That is, unlike the journal bearing, when the lubricating oil flows between the bearing pad and the thrust collar without approaching the bearing pad side like the thrust bearing, it is adjacent even if the seal fin as described above is used. The flow rate of carryover oil flowing into the bearing pad cannot be reduced sufficiently. Therefore, there is a possibility that the bearing pad cannot be efficiently cooled under the influence of carryover oil.

  The present invention has been made to solve the above-described problems, and provides a thrust bearing capable of efficiently cooling a bearing pad, and a rotary machine including the thrust bearing.

In order to solve the above problems, the present invention proposes the following means.
A thrust bearing according to a first aspect of the present invention is a thrust bearing that supports a rotating shaft having a rotating shaft main body that rotates about an axis, and a thrust collar that projects from the rotating shaft main body radially outward of the rotating shaft main body. A bearing provided between a plurality of bearing pads adjacent to the thrust collar and spaced from each other in the rotational direction of the rotary shaft main body so as to be in sliding contact with the thrust collar from the axial direction in which the axis extends. A first nozzle that ejects lubricating oil toward the thrust collar, and adjacent to the first nozzle between the adjacent bearing pads, and toward the outer side in the radial direction toward the thrust collar. A second nozzle that ejects fluid so as to incline toward the surface.

  According to such a configuration, the second nozzle causes the second overflow of the carryover oil flowing from the rear side in the rotational direction by ejecting the fluid so as to incline toward the outer side in the radial direction as it goes toward the thrust collar. The nozzle can be pushed away in the radial direction of the rotary shaft body at the position where the nozzle is disposed. Therefore, it is possible to reduce the flow rate of carryover oil that flows into another bearing pad adjacent to the front side in the rotational direction with respect to the cooled bearing pad. That is, the bearing pad is cooled and the temperature of the carry-over oil that has risen to prevent other adjacent bearing pads from being heated, and the other bearing pads are cooled by the lubricating oil newly supplied from the first nozzle. be able to. Therefore, it is possible to reduce the carry-over oil having a high temperature from flowing into the bearing pad.

  In the thrust bearing, the second nozzle may be arranged adjacent to the rear side in the rotational direction with respect to the first nozzle.

  According to such a configuration, the fluid ejected from the second nozzle does not hinder the lubricating oil ejected from the first nozzle from flowing toward the other bearing pad on the front side in the rotational direction. That is, even when fluid is ejected from the second nozzle, it is only necessary to push away the carry-over oil flowing from the rear side in the rotational direction and eject it from the first nozzle to the bearing pad adjacent to the front side in the rotational direction. There is no effect on the inflowing lubricant. Therefore, the lubricating oil supplied from the first nozzle can flow toward the bearing pad that is not cooled without being blocked, and the bearing pad that is not cooled can be cooled. Thereby, a bearing pad can be cooled more efficiently.

Further, in the thrust bearing, the second nozzle has a jet outlet for jetting the fluid,
A plurality of the jet nozzles may be arranged adjacent to each other in the radial direction.

  According to such a configuration, the fluid can be ejected over a wide radial range from the second nozzle to the carryover oil flowing in the rotation direction. Therefore, most of the carryover oil flowing from the rear side in the rotation direction can be pushed away in the radial direction. Therefore, it is possible to further reduce the flow rate of the hot carryover oil that flows into other bearing pads adjacent to the cooled bearing pad. That is, it is possible to more effectively suppress other uncooled bearing pads from being heated by carry-over oil whose temperature has been increased by cooling the bearing pads. Therefore, the bearing pad can be cooled more efficiently by further reducing the carryover oil flowing into the bearing pad.

  Further, in the thrust bearing, among the plurality of jet outlets, the jet outlet arranged on the outer side in the radial direction is the thrust of the fluid ejected from the jet outlet arranged on the inner side in the radial direction. The angle inclined with respect to the color may be an acute angle.

  According to such a configuration, in the second nozzle, the angle at which the fluid is inclined with respect to the thrust collar is formed at a sharper angle as the jet port is formed on the outer side in the radial direction. Accordingly, it is possible to increase the radially outward component of the flow velocity of the fluid ejected from the second nozzle. That is, as it goes outward in the radial direction, the force that pushes carryover oil outward in the radial direction can be increased. Therefore, the force that gradually pushes the carryover oil flowing in the rotational direction from the inner side to the outer side in the radial direction can be increased, and the carryover oil can be efficiently pushed away to the outer side in the radial direction.

  In the thrust bearing, the fluid may be the lubricating oil.

  According to such a configuration, the fluid ejected from the second nozzle is ejected from the first nozzle by using the same lubricant as the fluid ejected from the first nozzle as the fluid ejected from the second nozzle. Can be recovered together with the lubricating oil. Therefore, a structure for separately collecting the fluid ejected from the second nozzle and the lubricating oil ejected from the first nozzle becomes unnecessary, and the thrust bearing can be formed with a simple configuration. Therefore, it is possible to easily form a thrust bearing with high cooling efficiency.

  In the thrust bearing, the fluid may be a gas.

  According to such a configuration, the fluid can be ejected from the second nozzle at a faster flow rate than the liquid having the same pressure is ejected. Therefore, it can respond by applying a small pressure compared with the case where a liquid is used by jetting gas from a jet port at the same flow velocity as the case where a liquid is jetted from a jet port. Therefore, gas can be easily ejected at a flow rate equivalent to that of carryover oil flowing at high speed in the rotation direction. As a result, the carryover oil can be effectively swept away radially outward.

  Moreover, the rotary machine in the 2nd aspect of this invention is equipped with the said thrust bearing.

  According to such a configuration, the bearing pad can be efficiently cooled, and a thrust collar that requires high peripheral speed and high surface pressure can be stably supported as a thrust bearing. Therefore, the operation efficiency of the rotating machine can be improved by improving the operation efficiency.

  According to the present invention, by ejecting the fluid from the second nozzle, it is possible to suppress the inflow of carryover oil to the adjacent bearing pad and to cool the bearing pad efficiently.

It is a schematic block diagram of the steam turbine in each embodiment of this invention. It is sectional drawing of the thrust bearing in 1st embodiment of this invention. It is principal part sectional drawing explaining the 1st nozzle in each embodiment of this invention. It is principal part sectional drawing explaining the 2nd nozzle in 1st embodiment of this invention. It is a principal part enlarged view explaining the flow of the lubricating oil in 1st embodiment of this invention. It is principal part sectional drawing explaining the 2nd nozzle in 2nd embodiment of this invention. It is a principal part enlarged view explaining the flow of the lubricating oil in 2nd embodiment of this invention. It is principal part sectional drawing explaining the 2nd nozzle in 3rd embodiment of this invention. It is a graph explaining the relationship between the flow velocity and pressure in gas and liquid regarding the third embodiment of the present invention.

<< first embodiment >>
Hereinafter, a first embodiment according to the present invention will be described with reference to FIGS. 1 to 5.
A steam turbine 100 (rotary machine) according to an embodiment of the present invention will be described.
The steam turbine 100 is an external combustion engine that extracts the energy of the steam S as rotational power, and is used for a generator in a power plant.

As shown in FIG. 1, the steam turbine 100 includes a turbine casing 110, a rotating shaft 120 extending along the axis O so as to penetrate the turbine casing 110, a stationary blade 140 held by the turbine casing 110, and a rotation A moving blade 150 provided on the shaft 120 and a bearing portion 160 that supports the rotating shaft 120 so as to be rotatable around the axis O are provided.
The bearing portion 160 includes a journal bearing 161 and a thrust bearing 1, and supports the rotary shaft 120 in a rotatable manner.

  In such a steam turbine 100, the steam S introduced into the turbine casing 110 passes through a flow path between the stationary blade 140 and the moving blade 150. At this time, when the steam S rotates the rotor blade 150, the rotating shaft 120 rotates along with the rotor blade 150, and power (rotational energy) is supplied to a machine (not shown) such as a generator connected to the rotating shaft 120. Is transmitted.

The rotating shaft 120 includes a rotating shaft main body 121 that rotates around the axis O, and a thrust collar 122 that projects from the rotating shaft main body 121 to the outside in the radial direction D of the rotating shaft main body 121.
The rotating shaft main body 121 has a cylindrical shape with the axis O as the center, and extends in the direction of the axis O in which the axis O extends with respect to the turbine casing 110.
The thrust collar 122 has a disk shape with the axis O as the center. That is, the thrust collar 122 of the present embodiment integrally protrudes from the outer peripheral surface of the rotating shaft main body 121 to the outer side in the radial direction D of the rotating shaft main body 121 so as to form a flange shape.

Next, the thrust bearing 1 in this embodiment is demonstrated with reference to FIG.
The thrust bearing 1 supports the thrust collar 122 in the direction of the axis O of the rotation shaft 120. The thrust bearing 1 is provided with the same structure in the direction of the axis O across the thrust collar 122. In the present embodiment, the thrust bearing 1 disposed on one side in the axis O direction (the right side in FIG. 1) will be described as an example.

  As shown in FIG. 2, the thrust bearing 1 of the present embodiment includes a bearing casing 10 that is an exterior, a bearing pad 20 that is provided with a plurality in the rotational direction R of the rotating shaft body 121, and adjacent bearing pads. A first nozzle 30 disposed between the first nozzles 30 for supplying the low-temperature lubricating oil G, and a second nozzle 40 disposed adjacent to the first nozzles 30 between the adjacent bearing pads 20 to eject the fluid; It has.

  The bearing casing 10 covers the plurality of bearing pads 20, the first nozzle 30 and the second nozzle 40 from the outside. In the bearing casing 10, the cross-sectional shape in the direction of the axis O is an annular shape centered on the axis O, and the rotary shaft main body 121 is inserted through the center. The bearing casing 10 supports the bearing pad 20 in a swingable manner on a surface (not shown) facing the axis O direction. The bearing casing 10 fixes the first nozzle 30 and the second nozzle 40.

  The bearing pad 20 supports the rotating shaft 120 by supporting the thrust collar 122 from the direction of the axis O with the pad surface 21 via the lubricating oil G. That is, as shown in FIG. 3, the bearing pad 20 is disposed so that the pad surface 21 faces the thrust collar 122 and is in sliding contact with the thrust collar 122 from the direction of the axis O through the lubricating oil G. A plurality of bearing pads 20 are arranged adjacent to the rotation direction R so as to surround the rotary shaft main body 121 from the outer peripheral side in the bearing casing 10. Specifically, in the present embodiment, the six bearing pads 20 are arranged in an annular shape spaced evenly in the rotational direction R. The pad surface 21 of the bearing pad 20 is formed of a material that does not damage the thrust collar 122 when foreign matter or the like adheres. Specifically, the pad surface 21 of the present embodiment is formed of a soft metal such as white metal or a resin material having high heat resistance. The pad surface 21 of the bearing pad 20 of the present embodiment is made of, for example, an engineering plastic having high heat resistance such as PEEK or PTFE which is a resin material.

  Here, in the bearing pad 20 of the present embodiment, when the bearing pad 20 is viewed from the thrust collar 122 side in the axis O direction, the rear side in the rotational direction R of the pad surface 21 is the pad inlet side 21a, and the pad surface The front side of the rotational direction R in 21 is defined as a pad outlet side 21b. Further, in the present embodiment, as shown in FIG. 2, an annular imaginary line that passes through an intermediate position in the radial direction D of the rotary shaft main body 121 of the bearing pad 20 adjacent to the rotational direction R and has the axis O as the center. Is a pad center line CL.

  The first nozzle 30 is provided between the bearing pads 20 adjacent to each other in the rotation direction R. The first nozzle 30 is provided with a plurality of oil supply ports 300 which are openings for ejecting low temperature lubricating oil G toward the thrust collar 122. The first nozzle 30 ejects the compressed lubricating oil G from the oil supply port 300 into the bearing casing 10 via an oil pump P that compresses the lubricating oil G supplied from a supply source (not shown). The first nozzle 30 of the present embodiment has a pair of nozzles arranged between the bearing pads 20 adjacent in the rotation direction R. Specifically, the first nozzle 30 is located between the adjacent bearing pads 20 on the front side in the rotational direction R and the rear side in the rotational direction R between the adjacent bearing pads 20. And a rear first nozzle 32 arranged at the rear.

  The front first nozzle 31 is disposed adjacent to the bearing pad 20 on the rear side in the rotational direction R. The front first nozzle 31 of the present embodiment is formed so that the length in the radial direction D is approximately the same as that of the bearing pad 20. The front first nozzle 31 has four oil supply ports 300 that are spaced apart in the radial direction D of the rotary shaft main body 121. As shown in FIG. 3, the front first nozzle 31 ejects the lubricating oil G perpendicularly to the thrust collar 122 because the oil supply port 300 is opened along the axis O direction.

  The rear first nozzle 32 is disposed adjacent to the front side in the rotational direction R with respect to the bearing pad 20. The rear first nozzle 32 of this embodiment has the same structure as the front first nozzle 31. Specifically, the rear first nozzle 32 of the present embodiment is formed with four lengths in the radial direction D, which are approximately the same length as the bearing pad 20, and are spaced apart in the radial direction D. It has a mouth 300. As with the front first nozzle 31, the rear first nozzle 32 ejects the lubricating oil G perpendicularly to the thrust collar 122 by the oil supply port 300 opening along the direction of the axis O.

  In addition, the front 1st nozzle 31 and the back 1st nozzle 32 of this embodiment are connected to the supply source via the same oil pump P, when the supply pipe not shown branches in the middle. Accordingly, by driving the oil pump P, the lubricating oil G is supplied to the front first nozzle 31 and the rear first nozzle 32.

  The second nozzle 40 is provided adjacent to the first nozzle 30 between the bearing pads 20 adjacent to each other in the rotation direction R. The second nozzle 40 ejects fluid so as to incline toward the outer side in the radial direction D of the rotating shaft main body 121 as it goes toward the thrust collar 122. The second nozzle 40 is provided with an outlet 400 that is inclined with respect to the thrust collar 122.

  Specifically, the second nozzle 40 of the present embodiment is disposed so as to be sandwiched between the front first nozzle 31 and the rear first nozzle 32. That is, the second nozzle 40 is arranged adjacent to the front first nozzle 31 on the rear side in the rotation direction R and on the front side in the rotation direction R with respect to the rear first nozzle 32. In the second nozzle 40 of the present embodiment, the same low-temperature lubricating oil G as that ejected from the first nozzle 30 is used as the fluid. The second nozzle 40 is formed with a shorter length in the radial direction D than the front first nozzle 31 and the rear first nozzle 32. In the second nozzle 40 of the first embodiment, one ejection port 400 for ejecting the lubricating oil G is formed. The second nozzle 40 is connected to a supply source via the same oil pump P as that of the front first nozzle 31 and the rear first nozzle 32 because a supply pipe (not shown) branches in the middle. Therefore, by driving the oil pump P, the lubricating oil G is supplied in the same manner as the front first nozzle 31 and the rear first nozzle 32.

  As shown in FIG. 4, the jet nozzle 400 of the present embodiment is formed on the inner side in the radial direction D with respect to the pad center line CL in the second nozzle 40. The jet port 400 is formed so as to incline so that the lubricating oil G is jetted to the thrust collar 122 at a position outside the pad center line CL in the radial direction D. That is, the ejection port 400 is formed with an acute ejection angle, which is an angle at which the lubricating oil G is ejected so as to be inclined outward in the radial direction D with respect to the surface of the thrust collar 122 orthogonal to the axis O. .

Next, the operation of the thrust bearing 1 of the first embodiment will be described.
According to the thrust bearing 1 of the first embodiment, the rotary shaft main body 121 rotates together with the thrust collar 122 when the steam turbine 100 is driven. Then, when the oil pump P is driven, the lubricating oil G is supplied to the front first nozzle 31 and the rear first nozzle 32. The supplied lubricating oil G is ejected vertically from the oil supply port 300 toward the thrust collar 122 and flows into the gap between the thrust collar 122 and the pad surface 21 of the bearing pad 20. At the same time, in the thrust bearing 1, when the oil pump P is driven, the lubricating oil G is also supplied to the second nozzle 40, and the lubricating oil G is also ejected from the ejection port 400 toward the thrust collar 122.

  Here, while the bearing pad 20 and the first nozzle 30 are almost stationary, the thrust collar 122 rotates at a very high peripheral speed, so that the thrust collar from the front first nozzle 31 and the rear first nozzle 32 is provided. A very large speed difference is generated in the lubricating oil G that is ejected perpendicularly to 122 and filled in a narrow gap between the thrust collar 122 and the pad surface 21. When such a speed difference occurs, a shearing force acts on the lubricating oil G flowing into the gap, and a viscous force is generated inside the lubricating oil G. The viscous effect and the tilting of the pad surface 21 of the bearing pad 20 with respect to the thrust collar 122 cause a wedge effect, and an oil film pressure is generated in the lubricating oil G in the gap between the thrust collar 122 and the pad surface 21. Thus, the thrust collar 122 can be supported in the direction of the axis O.

  In addition, the lubricating oil G provides a lubricating action while generating an oil film pressure between the thrust collar 122 and the bearing pad 20, and cools the bearing pad 20 while flowing through the bearing casing 10. Specifically, the lubricating oil G flows at high speed in the bearing casing 10 along the rotation direction R of the rotating shaft body 121 as shown in FIG. 5 as the thrust collar 122 rotates at a high peripheral speed. Yes. Therefore, the lubricating oil G ejected perpendicularly from the oil supply port 300 of the front first nozzle 31 is the bearing pad 20 adjacent to the front side in the rotation direction R with respect to the front first nozzle 31 (for example, the front first nozzle The bearing pad 20 first cooled by the lubricating oil G ejected from 31 is referred to as the first bearing pad 20A), and flows into the gap between the pad surface 21 and the thrust collar 122, and the pad outlet Flows towards side 21b.

  Furthermore, centrifugal force is also generated in the circulating lubricating oil G toward the outside in the radial direction D of the rotating shaft main body 121. Therefore, the lubricating oil G that has flowed into the gap between the pad surface 21 of the first bearing pad 20A and the thrust collar 122 flows toward the front side in the rotational direction R of the rotating shaft body 121 and toward the outside in the radial direction D. .

  The lubricating oil G cools the bearing pad 20 by exchanging heat with the pad surface 21 while flowing through the gap between the pad surface 21 of the first bearing pad 20A and the thrust collar 122. At this time, by exchanging heat with the bearing pad 20, the lubricating oil G flows from the pad inlet side 21 a that is the front side in the flow direction of the lubricating oil G to the pad outlet side 21 b that is the back side in the flow direction of the lubricating oil G. As it goes, the temperature gradually rises. In particular, the lubricating oil G flowing out from the outer side in the radial direction D from the pad center line CL becomes higher in the pad outlet side 21b. The lubricating oil G having a temperature higher than that at the time of flowing in from the pad inlet side 21a is adjacent to the front side in the rotational direction R with respect to the first bearing pad 20A from the pad outlet side 21b of the first bearing pad 20A. It flows out as carryover oil toward the pad inlet side 21a of another bearing pad 20 that is not cooled (for example, the second bearing pad 20B).

  The carry-over oil that has flowed out from the pad outlet side 21b of the first bearing pad 20A reaches the position where the rear first nozzle 32 is disposed, so that the oil supply port 300 of the rear first nozzle 32 is directed toward the thrust collar 122. It is mixed with low-temperature lubricating oil G ejected vertically. Therefore, the carryover oil is cooled, the flow toward the rotation direction R is weakened, and the flow velocity is reduced. Of the carryover oil having passed through the rear first nozzle 32 and having a reduced flow velocity, the carryover oil flowing outside the pad center line CL in the radial direction D is lubricated from the outlet 400 of the second nozzle 40. G is ejected. The lubricating oil G ejected from the ejection port 400 at an acute angle toward the outside in the radial direction D of the thrust collar 122 causes the carryover oil to flow outside the pad center line CL in the radial direction D. It is forcibly changed in the direction toward. As a result, the carryover oil flowing outside the pad center line CL in the radial direction D does not reach the pad inlet side 21a of the second bearing pad 20B adjacent to the front side in the rotational direction R, and the second nozzle 40 It is swept toward the outside in the radial direction D at the arranged position. Low temperature lubricating oil G is ejected from the oil supply port 300 of the front first nozzle 31 adjacent to the front side in the rotation direction R with respect to the second nozzle 40 that has caused carryover oil to flow. Therefore, the low-temperature lubricating oil G ejected from the front first nozzle 31 flows into the gap between the second bearing pad 20B and the thrust collar 122, and the second bearing pad 20B is cooled as if the first bearing pad 20A was cooled. Cool down.

  According to the thrust bearing 1 as described above, the lubricating oil G is ejected so that the second nozzle 40 is inclined toward the outer side in the radial direction D toward the thrust collar 122, so that the rear side in the rotational direction R The carryover oil flowing from the position can be pushed away in the radial direction D of the rotary shaft main body 121 at the position where the second nozzle 40 is disposed. Therefore, it is possible to reduce the flow rate of carryover oil that flows into the second bearing pad 20B adjacent to the first bearing pad 20A on the front side in the rotational direction R. That is, the low temperature newly supplied from the front first nozzle 31 while suppressing the second bearing pad 20B from being heated by the carry-over oil which is the lubricating oil G whose temperature has been increased by cooling the first bearing pad 20A. The second bearing pad 20B can be cooled by the lubricating oil G. Therefore, the bearing pad 20 can be efficiently cooled by reducing the high temperature carryover oil from flowing into the second bearing pad 20B.

  Further, the second nozzle 40 is disposed adjacent to the rear side in the rotation direction R with respect to the front first nozzle 31, so that the lubricating oil G ejected from the ejection port 400 causes the first nozzle 31. The lubricating oil G ejected from the oil filler port 300 is not hindered from flowing toward the pad inlet side 21a of the second bearing pad 20B on the front side in the rotation direction R. That is, even if the lubricating oil G is ejected from the ejection port 400 of the second nozzle 40, the first bearing pad 20A flowing from the rear side in the rotational direction R is cooled and pushed away from the carryover oil that has become hot. As a result, the lubricating oil G ejected from the oil filler port 300 of the front first nozzle 31 is not affected. Therefore, the lubricating oil G supplied from the oil supply port 300 of the front first nozzle 31 flows into the second bearing pad 20B without being blocked, and the second bearing pad 20B can be cooled. Thereby, the bearing pad 20 can be cooled more efficiently.

  Furthermore, by using the same lubricant G as the lubricant G ejected from the first nozzle 30 to support the thrust collar 122 as the fluid ejected from the ejection port 400 of the second nozzle 40, The fluid ejected from the ejection port 400 can be collected together with the lubricating oil G ejected from the first nozzle 30. Therefore, a structure for separately collecting the fluid ejected from the second nozzle 40 from the bearing casing 10 and the lubricating oil G ejected from the first nozzle 30 becomes unnecessary, and the thrust bearing 1 is formed with a simple configuration. can do. Therefore, the thrust bearing 1 with high cooling efficiency can be easily formed.

  Further, the jet nozzle 400 of the second nozzle 40 is formed at an acute angle so that the lubricating oil G is jetted toward the thrust collar 122 outside the pad center line CL in the radial direction D. Therefore, the carryover oil flowing outside the radial direction D can be pushed out of the carryover oil flowing through the gap between the thrust collar 122 and the bearing pad 20. That is, among the carryover oil whose temperature has risen by cooling the first bearing pad 20A, the carryover oil that has flowed to the outside in the radial direction D on the pad outlet side 21b can be intensively swept away. In addition, since the force is smaller than the force necessary to push away the carryover oil that circulates in the entire area in the radial direction D at the position where the second nozzle 40 is disposed, the speed of the lubricating oil G to be ejected from the second nozzle 40 is set. Therefore, it is not necessary to use a large-scale oil pump P. Therefore, it is possible to form the second nozzle 40 with a simple configuration that can carry away carryover oil that has a strong adverse effect when the second bearing pad 20B is cooled. Thereby, the 2nd nozzle 40 which can exclude carryover oil efficiently can be formed easily.

  On the other hand, in the second nozzle 40 of the present embodiment, the lubricant oil G is not ejected from the second nozzle 40 toward the inner side in the radial direction D than the pad center line CL. Oil can flow toward the second bearing pad 20B. Of the carryover oil flowing out from the pad outlet side 21b, the carryover oil flowing inside the radial direction D is not so high in temperature as the carryover oil flowing outside the radial direction D, and the flow rate is small. Therefore, even if it flows into the gap between the second bearing pad 20B and the thrust collar, there is little influence such as heating and inhibiting cooling of the second bearing pad 20B. Therefore, by flowing the carryover oil flowing in the radial direction D toward the second bearing pad 20B, it can be used for cooling the second bearing pad 20B, and the flow rate of the lubricating oil G supplied from the front first nozzle 31 is suppressed. Can

  Further, the second nozzle 40 is formed so that the length in the radial direction D is shorter than that of the front first nozzle 31 and the rear first nozzle 32 having the same length in the radial direction D as the bearing pad 20. An open space can be formed outside the radial direction D of the nozzle 40. Therefore, a large space for the carryover oil to flow outside in the radial direction D can be secured by the second nozzle 40, and the carryover oil can be easily pushed away.

  Further, by providing the rear first nozzle 32, the flow velocity can be suppressed while cooling the carryover oil before reaching the second nozzle 40. Therefore, the force required to change the flow direction of the carryover oil flowing in the rotation direction R to the direction toward the radial direction D by the lubricating oil G ejected from the ejection port 400 of the second nozzle 40 can be reduced. Therefore, even if the speed of the lubricating oil G ejected from the second nozzle 40 is further suppressed and the speed component in the radial direction D becomes smaller, the lubricating oil G can be efficiently washed away. Thereby, since it is not necessary to use a large-scale oil pump P, the second nozzle 40 can be formed with a simpler configuration. In addition, it is possible to further cool the carryover oil that flows inside the radial direction D with respect to the pad center line CL whose temperature has not risen so much even when the first bearing pad 20A is cooled. Therefore, the carryover oil flowing inside the radial direction D can be used more effectively for cooling the second bearing pad 20B, and the flow rate of the lubricating oil G supplied from the front first nozzle 31 can be further suppressed.

  Further, since the steam turbine 100 which is a rotating machine includes such a thrust bearing 1, the bearing pad 20 can be efficiently cooled, and the thrust collar 122 that requires high peripheral speed and high surface pressure is provided as the thrust bearing 1. It can be supported stably. Therefore, since the rotating shaft 120 with a high peripheral speed and the rotating shaft 120 that is increased in size and is subjected to a high surface pressure can be stably supported, the operating efficiency is improved and the operating performance of the steam turbine 100 is improved. be able to.

<< Second Embodiment >>
Next, the thrust bearing 1a of 2nd embodiment is demonstrated with reference to FIG.6 and FIG.7.
In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The thrust bearing 1a of the second embodiment is different from the first embodiment with respect to the second nozzle 41.

  In the second nozzle 41 of the second embodiment, a plurality of jet nozzles 410 are arranged adjacent to each other in the radial direction D as shown in FIG. Specifically, the second nozzle 41 of the second embodiment is arranged at a position on the outer side in the radial direction D than the second nozzle 40 of the first embodiment, and is formed to have a longer length in the radial direction D. The second nozzle 41 is formed with three ejection ports 410 that are equally spaced in the radial direction D.

  The jet port 410 in the second embodiment includes a first jet port 411, a second jet port 412, and a third jet port 413 having different jet angles at which the lubricating oil G is jetted. Each ejection port 410 is formed in the order of the first ejection port 411, the second ejection port 412, and the third ejection port 413 from the inner side in the radial direction D with respect to the second nozzle 41. As for the spout 410, the spout 410 arranged on the outer side in the radial direction D out of the first spout 411 to the third spout 413 is more effective than the spout 410 arranged on the inner side in the radial direction D. The jet angle is further inclined to be an acute angle.

  Among the three jet nozzles 410, the first jet nozzle 411 is formed on the innermost side in the radial direction D and has the largest jet angle. Specifically, the first jet nozzle 411 is formed inside the radial direction D with respect to the pad center line CL in the second nozzle 41. The first ejection port 411 of the present embodiment is formed to be inclined with respect to the thrust collar 122 so that the lubricating oil G is ejected to a position slightly outside the pad center line CL in the radial direction D.

  The second jet nozzle 412 is formed so that the jet angle is smaller than the first jet nozzle 411 and larger than the third jet nozzle 413. The second ejection port 412 is formed between the first ejection port 411 and the third ejection port 413 outside the pad center line CL in the radial direction D in the second nozzle 41.

  The 3rd jet nozzle 413 is formed in the outermost side of the radial direction D among the three jet nozzles 410, and is formed in the smallest jet angle. Specifically, the third ejection port 413 is formed at the outermost side in the radial direction D in the second nozzle 41. The third ejection port 413 of the present embodiment is formed to be inclined so that the lubricating oil G is ejected toward the outer peripheral end of the thrust collar 122.

Next, the operation of the thrust bearing 1a of the second embodiment will be described.
According to the thrust bearing 1a of the second embodiment, in the same way as in the first embodiment, the second is the second against the carryover oil that has flowed out from the pad outlet side 21b of the first bearing pad 20A and passed through the rear first nozzle 32. The lubricating oil G is ejected at an acute angle from the first ejection port 411, the second ejection port 412, and the third ejection port 413 of the nozzle 41 toward the outside in the radial direction D of the thrust collar 122. The lubricating oil G ejected from the plurality of ejection ports 410 of the second nozzle 41 forces the flow direction of the carryover oil flowing outside the pad center line CL in the radial direction D toward the outside of the radial direction D. Changed to As a result, the carryover oil flowing outside the pad center line CL in the radial direction D does not reach the pad inlet side 21a of the second bearing pad 20B adjacent to the front side in the rotational direction R, and the second nozzle 41 It is swept toward the outside in the radial direction D at the arranged position.

  According to the thrust bearing 1a as described above, the plurality of jet nozzles 410 are formed in the second nozzle 41 adjacent to the radial direction D like the first jet nozzle 411 to the third jet nozzle 413. Lubricating oil G can be ejected over a wide range in the radial direction D with respect to the carryover oil flowing in the rotation direction R. Therefore, most of the carryover oil flowing from the rear side in the rotation direction R can be pushed away in the radial direction D. Therefore, the flow rate of carryover oil that flows into the second bearing pad 20B adjacent to the first bearing pad 20A can be further reduced. In other words, the first bearing pad 20A is more effectively suppressed from being heated by the carryover oil, which is the lubricating oil G whose temperature has been increased by cooling the first bearing pad 20A. The second bearing pad 20B can be cooled more efficiently by the low-temperature lubricating oil G supplied to. Therefore, the bearing pad 20 can be cooled more efficiently by further reducing the flow of high-temperature carryover oil into the second bearing pad 20B.

  Moreover, in the 2nd nozzle 41, the jet angle which jets the lubricating oil G in the jet nozzle 410 formed in the outer side of the radial direction D in order of the 1st jet nozzle 411, the 2nd jet nozzle 412, and the 3rd jet nozzle 413. By making it smaller and acute, the component of the speed toward the outside in the radial direction D in the flow velocity of the lubricant G to be ejected increases as it goes toward the outside in the radial direction D. Therefore, the force which pushes carryover oil to the outer side of radial direction D can be strengthened. Therefore, it is possible to gradually increase the force of the carryover oil flowing in the rotation direction R from the inner side in the radial direction D toward the outer side, and to efficiently carry the carryover oil to the outer side in the radial direction D. .

<< Third embodiment >>
Next, the thrust bearing 1b of 3rd embodiment is demonstrated with reference to FIG.8 and FIG.9.
In 3rd embodiment, the same code | symbol is attached | subjected to the component similar to 1st embodiment and 2nd embodiment, and detailed description is abbreviate | omitted. The thrust bearing 1b of the third embodiment is different from the first embodiment and the second embodiment regarding the fluid ejected from the ejection port 420 of the second nozzle 42.

  That is, as shown in FIG. 8, the second nozzle 42 of the third embodiment ejects a gas, not a liquid, as a fluid from an ejection port 420 of the second nozzle 42. Specifically, the second nozzle 42 of the third embodiment has the same shape as the second nozzle 40 of the first embodiment, but the compressor C compresses air instead of the oil pump P. have. Therefore, the second nozzle 42 of the third embodiment ejects the compressed air A from the ejection port 420 when the compressed air A is generated via the compressor C. The jet nozzle 420 of the third embodiment is formed so that the jet angle at which the compressed air A is jetted is the same angle as the jet nozzle 400 from which the lubricating oil G was jetted in the first embodiment. That is, the ejection port 420 of the third embodiment also has an ejection angle inclined toward the outer side in the radial direction D with respect to the surface of the thrust collar 122 orthogonal to the axis O from which the lubricating oil G is ejected. Is formed.

  According to the thrust bearing 1b as described above, by ejecting the compressed air A from the ejection port 420, it can be ejected at a higher flow velocity than when a liquid such as the lubricating oil G is ejected at the same pressure. Specifically, since the flow velocity is proportional to the reciprocal of the square root of the density, in the case of a gas having a very low density with respect to the liquid, when the same pressure is applied to the same flow rate as the liquid, as shown in FIG. The flow rate is 20 to 30 times that of the liquid. Therefore, the compressed air A is ejected from the ejection port 420 via the compressor C, so that it is smaller than the case where the lubricating oil G is compressed by the oil pump P and ejected from the ejection port 400 as in the first embodiment. The flow rate can be increased by simply applying pressure. Accordingly, it is possible to easily eject the high-speed compressed air A to the carryover oil flowing at a high speed in the rotation direction R. As a result, the carryover oil can be pushed more effectively outward in the radial direction D.

  Further, the compressor C that compresses a gas such as air is a small-scale device when a fluid is ejected at an equivalent flow rate as compared with a device that compresses liquid, such as an oil pump P that compresses the lubricating oil G. be able to. Therefore, the second nozzle 42 with high cooling efficiency can be easily formed.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the configurations and combinations of the embodiments in the embodiments are examples, and the addition and omission of configurations are within the scope not departing from the gist of the present invention. , Substitutions, and other changes are possible. Further, the present invention is not limited by the embodiments, and is limited only by the scope of the claims.

  The fluid ejected from the second nozzles 40 and 41 is the same as the lubricating oil G supplied from the front first nozzle 31 and the rear first nozzle 32 as in the first embodiment and the second embodiment. It is not limited to. For example, the fluid ejected from the second nozzles 40 and 41 may be another liquid different from the lubricating oil G such as a cooling oil capable of cooling the lubricating oil G. Furthermore, the gas ejected from the second nozzle 42 is not limited to the compressed air A as in the third embodiment. For example, the gas ejected from the second nozzle 42 only needs to have a density lower than that of the lubricating oil G, and may be a gas such as nitrogen.

  Moreover, in 2nd embodiment, although it changed and formed so that the jet angle from the 1st jet nozzle 411 to the 3rd jet nozzle 413 may become an acute angle gradually, it is not limited in this way, A thrust collar It suffices if it is formed so as to incline toward the outside in the radial direction D as it goes to 122 and to eject the fluid. Therefore, for example, the first nozzle 411 to the third nozzle 413 of the second nozzle 41 of the second embodiment are all formed at the same ejection angle, or only the second nozzle 412 is formed by changing the ejection angle. It may be done.

  Further, when the fluid is ejected toward the thrust collar 122 by the plurality of ejection ports, the structure is limited to a structure in which the plurality of ejection ports 420 are formed for one second nozzle 42 as in the second embodiment. It is not what is done. For example, one jet port 400 may be formed for one second nozzle 40 as in the first embodiment, and a plurality of the second nozzles 40 may be arranged in the radial direction D. That is, any structure may be used as long as fluid can be ejected from the plurality of ejection ports to the thrust collar 122. Therefore, the number of the ejection ports 400 and 410 formed in the second nozzles 40 and 41 is not limited to one or three as in this embodiment. For example, the second nozzle 41 may have four outlets 410 like the front first nozzle 31 and the rear first nozzle 32, or may have a larger number of outlets 410. .

  Further, the first nozzle 30 is not limited to having the two configurations of the front first nozzle 31 and the rear first nozzle 32 as in the present embodiment, and the thrust collar between the adjacent bearing pads 20 is not limited. What is necessary is just to be able to eject the lubricating oil G toward 122. For example, only the front first nozzle 31 may be provided as the first nozzle 30, and the lubricant oil G other than the front first nozzle 31 and the rear first nozzle 32 may be ejected. Good. Therefore, the number of the oil supply ports 300 formed in the front first nozzle 31 and the rear first nozzle 32 is not limited to four as in the present embodiment, and may be one or two. There may be more than one.

  Furthermore, this invention is not limited to the combination of 1st embodiment to 3rd embodiment, You may combine each embodiment. For example, a gas such as compressed air A may be ejected from the second nozzle 41 having a plurality of ejection ports 410 as in the second embodiment, as in the third embodiment.

  Furthermore, the rotary machine of the present invention is not limited to the steam turbine 100 as in the present embodiment, and may be a machine having the rotary shaft 120. For example, the rotating machine may be a gas turbine, a pump, or an engine.

DESCRIPTION OF SYMBOLS 100 ... Steam turbine S ... Steam 110 ... Turbine casing 120 ... Rotating shaft O ... Axis 121 ... Rotating shaft main body 122 ... Thrust collar R ... Rotating direction D ... Radial direction 140 ... Stator blade 150 ... Moving blade 160 ... Bearing part 161 ... Journal Bearing 1, 1a, 1b ... Thrust bearing 10 ... Bearing casing 20 ... Bearing pad 21 ... Pad surface 21a ... Pad inlet side 21b ... Pad outlet side CL ... Pad center line 30 ... First nozzle 31 ... Front first nozzle 32 ... Rear 1st nozzle 300 ... Oil supply port P ... Hydraulic pump 40, 41, 42 ... 2nd nozzle 400, 410, 420 ... Outlet G ... Lubricating oil 20A ... 1st bearing pad 20B ... 2nd bearing pad 411 ... 1st outlet 412 ... Second outlet 413 ... Third outlet C ... Compressor A ... Compressed air

Claims (7)

A thrust bearing that supports a rotating shaft having a rotating shaft main body that rotates about an axis, and a thrust collar that projects from the rotating shaft main body on the outer side in the radial direction of the rotating shaft main body,
A bearing pad provided with a plurality in a rotational direction of the rotary shaft main body so as to be in sliding contact with the thrust collar from an axial direction in which the axis extends.
A first nozzle which is provided between the bearing pads adjacent to each other, and jets lubricating oil toward the thrust collar;
A second nozzle provided adjacent to the first nozzle between the adjacent bearing pads, and ejecting fluid so as to incline toward the outer side in the radial direction toward the thrust collar;
A thrust bearing comprising.   The thrust bearing according to claim 1, wherein the second nozzle is disposed adjacent to a rear side in the rotation direction with respect to the first nozzle. The second nozzle has a spout for ejecting the fluid,
The thrust bearing according to claim 1 or 2, wherein a plurality of the jet outlets are arranged adjacent to each other in the radial direction.   Of the plurality of jet outlets, the jet outlet arranged on the outer side in the radial direction is inclined with respect to the thrust collar of the fluid jetted from the jet outlet arranged on the inner side in the radial direction. The thrust bearing according to claim 3, wherein the bearing is formed to have an acute angle.   The thrust bearing according to any one of claims 1 to 4, wherein the fluid is the lubricating oil.   The thrust bearing according to any one of claims 1 to 4, wherein the fluid is a gas.   A rotary machine comprising the thrust bearing according to any one of claims 1 to 6.

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