Compressor and compressor system

Abstract

To stably suppress the vibration of a rotor which is rotated at a high speed.SOLUTION: A compressor system includes a driving machine, and a compressor, the compressor including the rotor which can be rotated around the axis line, a casing covering the rotor, and a squeeze film damper arranged at the end of the rotor for enabling the indirect suppression of the vibration of the rotor via fluid. The rotor has a plurality of impellers having a solid structure which is formed in a disc shape with the axis line as a center and the center of which is embedded, and neighboring one another in the axial direction that the axis line extends, and a bolt fixing part having a plurality of bolts for fixing the plurality of impellers arranged side by side in the axial direction, in groups. The squeeze film damper is arranged at the end of the rotor not connected to another rotary machine, in the axial direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a compressor and a compressor system.

Background Art

[0002] Generally, a centrifugal compressor includes a rotor having a plurality of impellers and a casing that covers the impellers from the outside to form a flow path therebetween. In a centrifugal compressor, a fluid supplied from the outside through a flow path formed in the casing is compressed by the rotation of the impeller.

[0003] For example, as described in Patent Document 1, in such a centrifugal compressor, the rotor is formed by laminating a plurality of impellers in the axial direction. In this centrifugal compressor, the plurality of laminated impellers are fixed by a large tie bolt, which is a shaft arranged to pass through a large hole formed at the center of the impeller.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, when the rotor is rotated at high speed, the peripheral speed on the outer peripheral surface of the rotor increases. In order to support such a rotor with a high peripheral speed, it is necessary to reduce the size of the bearing. As a result, it is necessary to reduce the shaft diameter of the rotor. On the other hand, in order to increase the impeller peripheral speed by rotating the rotor at high speed, it is necessary to increase the diameter of the impeller. Further, when the diameter of the impeller increases and the fluid is compressed in multiple stages, the axial length of the rotor increases in proportion to the size of the impeller. Furthermore, as the axial length increases, the vibration generated in the rotor increases, but since the size of the bearing that supports the rotor is small, it becomes difficult to control the large vibration. Therefore, it is desired to stably suppress the vibration of the high-speed rotating rotor.

[0006] The present disclosure has been made to solve the above problems, and an object thereof is to provide a compressor and a compressor system capable of stably suppressing the vibration of a high-speed rotating rotor.

Means for Solving the Problems

[0007] To solve the above problems, a compressor according to the present disclosure includes a rotor rotatable about an axis, a casing that covers the rotor from the outside in the radial direction with respect to the axis, and a squeeze film damper disposed at an end of the rotor and capable of indirectly suppressing the vibration of the rotor through a fluid. The rotor is formed in a disk shape centered on the axis and has a solid structure with a filled center, a plurality of impellers adjacent to each other in the axial direction in which the axis extends, and a bolt fixing portion having a plurality of bolts that collectively fix the plurality of impellers arranged in the axial direction. The squeeze film damper is disposed at an end of the rotor that is not connected to other rotating machines in the axial direction.

[0008] In addition, the compressor system according to the present disclosure includes the compressor that compresses a working fluid, and a drive machine that has a drive shaft rotating around an axis and drives the compressor. The squeeze film damper is disposed at an end of the rotor that is far from the drive machine in the axial direction.

Advantages of the Invention

[0009] According to the compressor and the compressor system of the present disclosure, vibrations of a high-speed rotating rotor can be stably suppressed.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0011] Hereinafter, with reference to the accompanying drawings, modes for implementing a compressor system 1 according to the present disclosure will be described. However, the present disclosure is not limited to only this embodiment.

[0012] (Configuration of Compressor System) Hereinafter, the compressor system 1 according to the embodiment of the present disclosure will be described with reference to FIG. 1. The compressor system 1 is disposed, for example, in a chemical plant. As shown in FIG. 1, the compressor system 1 includes a drive machine 200, a speed changer 300, a compressor 100, a first coupling 410, and a second coupling 420. The drive machine 200, the speed changer 300, and the compressor 100 are coaxially arranged via the first coupling 410 and the second coupling 420 such that the central axes of their respective rotors 3 coincide with the axis O of the compressor 100.

[0013] Note that hereinafter, the direction in which the axis O extends is defined as the axial direction Da. The radial direction with respect to the axis O is simply referred to as the radial direction Dr. Also, the direction around the rotor 3 centered on the axis O is defined as the circumferential direction Dc. In the compressor system 1, the side where the compressor 100 is disposed with respect to the speed changer 300 is referred to as the first side Da1 in the axial direction Da. In the compressor system 1, the side where the compressor 100 is disposed with respect to the speed changer 300 is referred to as the second side Da2 in the axial direction Da. Also, in the radial direction Dr, the side approaching the axis O is referred to as the inner side Dri in the radial direction Dr. Also, in the radial direction Dr, the side away from the axis O is referred to as the outer side Dro in the radial direction Dr.

[0014] The drive machine 200 is capable of driving the compressor 100. The drive machine 200 is, for example, a steam turbine that drives the compressor 100 using the steam generated by the treatment of the working fluid (fluid), or an electric motor that drives the compressor 100 at a rotational speed based on the magnitude of the voltage applied from the outside. The drive machine 200 in the present embodiment has a drive shaft 210. The drive shaft 210 is rotatable about the axis O.

[0015] The transmission 300 increases or decreases the rotation speed of the drive machine 200 by a plurality of gears and transmits it to the compressor 100. The transmission 300 of the present embodiment is, for example, a speed increaser. The transmission 300 is arranged between the drive machine 200 and the compressor 100 in the axial direction Da. The transmission 300 has a transmission rotor 310. One end of the transmission rotor 310 is connected to the drive shaft 210 via the first coupling 410. The other end of the transmission rotor 310 is connected to the rotor 3 via the second coupling 420. The transmission rotor 310 is rotatable about the axis O.

[0016] (Configuration of Compressor) The compressor 100 is driven by the transmission of the rotation of the drive shaft 210 and compresses the working fluid. The compressor 100 is arranged on the first side Da1 of the axial direction Da with respect to the transmission 300. The compressor 100 compresses gas as the working fluid. The compressor 100 of the present embodiment is a single-shaft multi-stage centrifugal compressor (multi-stage centrifugal compressor) that compresses a gas having a molecular weight of 10 or less such as hydrogen gas. The compressor 100 is driven, for example, at a high rotational speed of 15,000 rpm or more. The power required for the compressor 100 is, for example, 1000 kw or more. Further, the suction pressure of the compressor 100 is set to 10 barA or more. As shown in FIG. 2, the compressor 100 includes a casing 2, a rotor 3, a seal portion 8, and a bearing portion 9.

[0017] (Configuration of Casing) The casing 2 covers the rotor 3 from the outside Dro in the radial direction Dr. The casing 2 of the present embodiment has an outer casing 21, a plurality of diaphragms 22, and a plurality of heads 23.

[0018] The outer casing 21 has a cylindrical shape centered on a central axis that is arranged to coincide with the axis O of the rotor 3. The first side Da1 (one side) in the axial direction Da of the outer casing 21 is open with a size that allows the bundle 10, which will be described later, to be inserted therethrough. An end plate 211 is formed on the second side Da2 (the other side) in the axial direction Da of the outer casing 21. The end plate 211 has a plate-like shape that extends perpendicular to the axial direction Da. An insertion hole 212 is formed at the center of the end plate 211 with a size that allows the rotor 3 to be inserted therethrough and does not allow the bundle 10 to be inserted therethrough. Thus, the bundle 10 can be inserted into and removed from the casing 2 by being moved in the axial direction Da with respect to the outer casing 21.

[0019] The plurality of diaphragms 22 are arranged to cover the rotor 3 from the outer side Dro in the radial direction Dr. The plurality of diaphragms 22 are arranged inside the outer casing 21. The diaphragm 22 has an annular shape centered on the axis O. The plurality of diaphragms 22 are laminated so as to form a cylindrical shape extending in the axial direction Da. Between adjacent diaphragms 22, the outer peripheral surfaces are fixed to each other by welding or bolts 71. By fixing the plurality of diaphragms 22 to each other, a flow path for introducing into the impeller 3 is formed inside. Also, the plurality of diaphragms 22, together with the head 23, the rotor 3, the seal portion 8, and the bearing portion 9, constitute the bundle 10. The bundle 10 is housed inside the outer casing 21. In the bundle 10, the rotor 3, the plurality of diaphragms 22, the plurality of heads 23, the seal portion 8, and the bearing portion 9 are in a state where they can all move together so as to be integral.

[0020] (Configuration of the flow path) Here, specifically, the flow path formed in the casing 2 by the diaphragm 22 will be described in order from the upstream side, which is the first side Da1 in the axial direction Da, toward the downstream side, which is the second side Da2 in the axial direction Da. In the present embodiment, the diaphragm 22 forms, together with the outer casing 21 and the head 23, a suction port 221, a plurality of casing flow paths 222, and a discharge port 223 in order from the upstream side through which gas flows.

[0021] The suction port 221 allows the gas before compression flowing in from outside the casing 2 to flow into the interior of the diaphragm 22. The suction port 221 has the gas flowing therein that is to flow into the most upstream impeller 30.

[0022] The casing flow path 222 is formed inside the diaphragm 22. The casing flow path 222 supplies the gas from the suction port 221 to the most upstream impeller 30, supplies the gas discharged from the upstream impeller 30 to the impeller 30 arranged downstream, or feeds the gas discharged from the most downstream impeller 30 into the discharge port 223.

[0023] The discharge port 223 discharges the gas that has flowed inside the diaphragm 22 and been compressed to the outside of the casing 2. The discharge port 223 discharges the gas discharged from the most downstream impeller 30 to the outside.

[0024] The pair of heads 23 are annular members and are arranged inside the outer casing 21. The heads 23 are formed to have a size capable of closing the openings at both ends of the outer casing 21. As the heads 23 in the present embodiment, there are a suction-side head 231 arranged on the first side Da1 in the axial direction Da with respect to the plurality of diaphragms 22, and a discharge-side head 232 arranged on the second side Da2 in the axial direction Da with respect to the plurality of diaphragms 22.

[0025] The suction-side head 231 is arranged at a position closer to the suction port 221 than the discharge-side head 232. The suction-side head 231 forms the suction port 221 together with the diaphragm 22 arranged on the most first side Da1 in the axial direction Da. The suction-side head 231 is fixed to the integrated plurality of diaphragms 22 by bolts 71 or the like. Thereby, the suction-side head 231 is integrated with the diaphragm 22.

[0026] The discharge-side head 232 is disposed at a position closer to the discharge port 223 than the suction-side head 231. The discharge-side head 232 forms the discharge port 223 together with the diaphragm 22 disposed on the second side Da2 in the axial direction Da. The discharge-side head 232 is fixed to the plurality of integrated diaphragms 22 by bolts 71 or the like. As a result, the discharge-side head 232 is integrated with the diaphragm 22.

[0027] (Configuration of Rotor) The rotor 3 is housed inside the casing 2. The rotor 3 is rotatable about the axis O. The rotor 3 of the present embodiment has a plurality of impellers 30, a shaft end member 5, and a bolt fixing portion 70.

[0028] The impeller 30 compresses gas by utilizing centrifugal force when rotating. The impeller 30 is formed in a disk shape centered on the axis O and has a solid structure with a filled center. The plurality of impellers 30 are adjacent in the axial direction Da. Each impeller 30 is a so-called closed impeller including a disk, a plurality of blades, and a cover. An impeller flow path 301 for allowing gas to flow is formed inside the impeller 30. The impeller 30 has an impeller peripheral speed of 400 m / s or more. For example, four or more impellers 30 are arranged.

[0029] The impeller 30 is formed in a disk shape centered on the axis O and has a solid structure with a filled center. The impeller 30 of the present embodiment has an impeller shaft portion 41 and an impeller outer peripheral portion 42.

[0030] The impeller shaft portion 41 is formed in a circular cross-sectional shape centered on the axis O. The length of the impeller shaft portion 41 in the axial direction Da is formed to be approximately the same size as one diaphragm 22. The impeller outer peripheral portion 42 protrudes from the impeller shaft portion 41 toward the outer side Dro in the radial direction Dr so as to extend from the outer edge of the impeller shaft portion 41. The impeller outer peripheral portion 42 is integrally formed with the impeller shaft portion 41 and formed as one member. An impeller flow path 301 is formed in the impeller outer peripheral portion 42.

[0031] Further, the impeller shaft portion 41 of the present embodiment has bolt holes 38. The bolt holes 38 are formed so as to penetrate the impeller shaft portion 41. The bolt holes 38 are formed in the impeller shaft portion 41. A plurality of (for example, twelve) bolt holes 38 are formed at intervals in the circumferential direction Dc centered on the axis O. The plurality of bolt holes 38 are arranged at equal intervals in the circumferential direction Dc. Each bolt hole 38 is formed so as to penetrate the impeller shaft portion 41 in the axial direction Da at a position deviated outward Dro from the axis O in the radial direction Dr. A bolt 71 described later is inserted into each bolt hole 38.

[0032] (Configuration of shaft end member) The shaft end member 5 is connected to the impellers 30 arranged at both ends in the axial direction Da with respect to the plurality of impellers 30 arranged in the axial direction Da. The shaft end member 5 of the present embodiment includes a first shaft end member 50 and a second shaft end member 60.

[0033] The first shaft end member 50 is arranged at the position on the first side Da1 in the axial direction Da with respect to the plurality of impellers 30 fixed together. The first shaft end member 50 of the present embodiment is fixed to the most upstream impeller 30. The position of the first shaft end member 50 in the axial direction Da is arranged at a position overlapping the suction side head 231. The first shaft end member 50 of the present embodiment has a first shaft portion 51, a first supported portion 52, and a first enlarged diameter portion 53.

[0034] The first shaft portion 51 is formed in a columnar shape extending in the axial direction Da about the axis O. When viewed from the axial direction Da, the first shaft portion 51 is formed in a columnar shape centered on the axis O and smaller than the impeller shaft portion 41. A thrust collar 511 is formed on the first shaft portion 51. The thrust collar 511 protrudes outward in the radial direction Dr, forming an annular shape with respect to the first shaft portion 51. The thrust collar 511 is formed at a position significantly separated from the first supported portion 52 and the first enlarged diameter portion 53 toward the first side Da1 in the axial direction Da. The region where the thrust collar 511 is formed is the region supported by a thrust bearing 93 described later. The outer diameter of the thrust collar 511 is, for example, 120 mm or more. The first shaft portion 51 can be rotatably supported about the axis O in the circumferential direction Dc by a bearing portion 9 described later.

[0035] The first supported portion 52 is the region supported by a first journal bearing 91 described later. The first supported portion 52 is formed at a position close to the plurality of impellers 30 with respect to the first shaft portion 51. The first supported portion 52 is connected to the end portion of the second side Da2 of the first shaft portion 51 in the axial direction Da. The first supported portion 52 is arranged adjacent to the first enlarged diameter portion 53 in the axial direction Da. The first supported portion 52 protrudes outward in the radial direction Dr with respect to the first shaft portion 51. The first supported portion 52 extends in the circumferential direction Dc. When viewed from the axial direction Da, the first supported portion 52 is formed in a disk shape that expands outward in the radial direction Dr with respect to the first shaft portion 51. The outer diameter of the first supported portion 52 in the field is formed smaller than the outer diameter of the thrust collar 511. For example, the outer diameter of the region where the first supported portion 52 is supported by the first journal bearing 91 is 120 mm or less. The first enlarged diameter portion 53 is formed integrally with the first shaft portion 51.

[0036] The first enlarged diameter portion 53 is formed at a position close to the plurality of impellers 30 with respect to the first supported portion 52. The first enlarged diameter portion 53 is connected to the end portion of the second side Da2 of the first supported portion 52 in the axial direction Da. The first enlarged diameter portion 53 is disposed adjacent to the impeller shaft portion 41 of the most upstream impeller 30 in the axial direction Da. The first enlarged diameter portion 53 protrudes outward Dro in the radial direction Dr with respect to the first supported portion 52. The first enlarged diameter portion 53 is a region that protrudes most outward Dro in the radial direction Dr in the first shaft end member 50. The first enlarged diameter portion 53 extends in the circumferential direction Dc. The first enlarged diameter portion 53 is formed in a disk shape that expands outward Dro in the radial direction Dr with respect to the first supported portion 52 when viewed from the axial direction Da. The first enlarged diameter portion 53 is integrally formed with the first shaft portion 51 and the first supported portion 52 and formed as one member. Further, the first enlarged diameter portion 53 has a first nut accommodation recess 531 and a first shaft end bolt hole 532.

[0037] The first nut accommodation recess 531 is formed to be able to accommodate the nut 72. The first nut accommodation recess 531 is recessed from the side surface facing the first side Da1 in the axial direction Da of the first enlarged diameter portion 53 toward the second side Da2 in the axial direction Da. A plurality of first nut accommodation recesses 531 are formed at positions overlapping the bolt hole 38 when viewed from the axial direction Da. The first nut accommodation recess 531 is formed in a circular shape larger than the bolt hole 38 with the bolt hole 38 as the center when viewed from the axial direction Da.

[0038] The first shaft end bolt hole 532 is formed to penetrate the first enlarged diameter portion 53 at a position offset outward Dro from the axis O in the radial direction Dr in the axial direction Da. The first shaft end bolt hole 532 penetrates the first enlarged diameter portion 53 from the first nut accommodation recess 531. A plurality of first shaft end bolt holes 532 are formed in the circumferential direction Dc centered on the axis O. The first shaft end bolt hole 532 is a hole formed in a circular shape slightly larger than the outer shape of the bolt 71 when viewed from the axial direction Da. The first shaft end bolt hole 532 of the present embodiment is formed to have the same position and the same shape as the bolt hole 38 when viewed from the axial direction Da.

[0039] The second shaft end member 60 is connectable to the rotor 3 of other rotating machines such as the drive machine 200 and the transmission 300. The second shaft end member 60 is arranged at a position on the second side Da2 in the axial direction Da with respect to the plurality of impellers 30 fixedly assembled. The second shaft end member 60 of the present embodiment is fixed to the most downstream impeller 30. The second shaft end member 60 is arranged at a position where the position in the axial direction Da overlaps with the discharge side head 232. The second shaft end member 60 has a second shaft portion 61 and a balance piston portion 62.

[0040] The second shaft portion 61 is formed in a columnar shape extending in the axial direction Da around the axis O. When viewed from the axial direction Da, the second shaft portion 61 is formed in a columnar shape centered on the axis O and smaller than the impeller shaft portion 41. The second shaft portion 61 can be rotatably supported around the axis O in the circumferential direction Dc by a bearing portion 9 described later.

[0041] The balance piston portion 62 is formed at a position close to the plurality of impellers 30 with respect to the second shaft portion 61. The balance piston portion 62 is connected to the end portion of the first side Da1 of the second shaft portion 61 in the axial direction Da. The balance piston portion 62 is disposed on the second side Da2 in the axial direction Da with respect to the plurality of impellers 30. The balance piston portion 62 is disposed adjacent to the impeller shaft portion 41 in the axial direction Da. The balance piston portion 62 is disposed at a position where it overlaps with the discharge side head 232 in the axial direction Da. The balance piston portion 62 protrudes from the second shaft portion 61 to the outside Dro in the radial direction Dr. The balance piston portion 62 extends in the circumferential direction Dc. When viewed from the axial direction Da, the balance piston portion 62 is formed in a disk shape that expands to the outside Dro in the radial direction Dr with respect to the second shaft portion 61 and the impeller shaft portion 41. The balance piston portion 62 is integrally formed with the second shaft portion 61 and formed as one member. The balance piston portion 62 is disposed facing the space where the working fluid discharged from the most downstream impeller 30 is located and the space where the working fluid supplied to the most upstream impeller 30 is located. Thereby, a thrust force is generated in the balance piston portion 62 from the first side Da1 to the second side Da2 in the axial direction Da. Further, the balance piston portion 62 has a second nut accommodation recess 621 and a second shaft end bolt hole 622.

[0042] The second nut accommodation recess 621 is formed to be able to accommodate the nut 72. The second nut accommodation recess 621 is recessed from the side surface facing the second side Da2 in the axial direction Da of the balance piston portion 62 toward the first side Da1 in the axial direction Da. A plurality of second nut accommodation recesses 621 are formed at positions overlapping the bolt hole 38 when viewed from the axial direction Da. The second nut accommodation recess 621 is formed in a circular shape larger than the bolt hole 38 with the bolt hole 38 as the center when viewed from the axial direction Da.

[0043] The second shaft end bolt hole 622 is formed so as to penetrate the balance piston portion 62 in the axial direction Da at a position offset outward Dro from the axis O in the radial direction Dr. The second shaft end bolt hole 622 penetrates the balance piston portion 62 from the second nut accommodation recess 621. A plurality of second shaft end bolt holes 622 are formed in the circumferential direction Dc centered on the axis O. The second shaft end bolt hole 622 is a hole formed in a circular shape slightly larger than the outer shape of the bolt 71 when viewed from the axial direction Da. The second shaft end bolt hole 622 of the present embodiment is formed so as to have the same position and the same shape as the bolt hole 38 when viewed from the axial direction Da.

[0044] (Configuration of bolt fixing portion) The bolt fixing portion 70 collectively fixes a plurality of impellers 30 arranged in the axial direction Da and the shaft end member 5. The bolt fixing portion 70 includes a plurality of bolts 71 and a pair of nuts 72.

[0045] The plurality of bolts 71 are inserted into the respective bolt holes 38 formed in the plurality of impellers 30. Each bolt 71 is composed only of a threaded portion without a head like a stud bolt. Each bolt 71 has an axial length Da such that the end portion reaches the first nut accommodation recess 531 and the second nut accommodation recess 621 in a state of being inserted into the bolt hole 38. That is, the end portion of the bolt 71 on the first side Da1 in the axial direction Da is arranged so as to reach the first nut accommodation recess 531. The end portion of the bolt 71 on the second side Da2 in the axial direction Da is arranged so as to reach the second nut accommodation recess 621. The plurality of bolts 71 are preferably arranged as close as possible to the inner side Dri in the radial direction Dr at the impeller shaft portions 41 of the plurality of impellers 30.

[0046] The pair of nuts 72 are fastened to both ends of each of the plurality of bolts 71. The nut 72 is fastened to the end portion of the bolt 71 on the first side Da1 in the axial direction Da within the first nut accommodation recess 531. Another nut 72 is fastened to the end portion of the bolt 71 on the second side Da2 in the axial direction Da within the second nut accommodation recess 621. Thereby, the plurality of impellers 30 are fixed in a state where they cannot move relative to each other.

[0047] (Configuration of the seal part) The seal part 8 seals between the rotor 3 and the casing 2. The seal part 8 of the present embodiment has a first seal part 8A, a second seal part 8B, and a third seal part 8C.

[0048] The first seal part 8A seals between the suction side head 231 and the first shaft part 51. The first seal part 8A is a dry gas seal. The first seal part 8A is detachable from the suction side head 231 and the first shaft part 51.

[0049] The second seal part 8B seals between the discharge side head 232 and the second shaft part 61. The second seal part 8B is a dry gas seal. The second seal part 8B is detachable from the discharge side head 232 and the second shaft part 61.

[0050] The third seal part 8C seals between the discharge side head 232 and the balance piston part 62. The third seal part 8C is a labyrinth seal. The third seal part 8C is arranged at a position separated from the second seal part 8B on the first side Da1 in the axial direction Da. The third seal part 8C is fixed to the discharge side head 232.

[0051] (Configuration of the bearing part) The bearing part 9 supports the rotor 3 rotatably about the axis O with respect to the casing 2. The bearing part 9 rotatably supports only the first shaft end member 50 and the second shaft end member 60. That is, in the rotor 3, the bearing part 9 does not overlap with the plurality of impellers 30 in the axial direction Da, and only overlaps with the first shaft end member 50 and the second shaft end member 60 in position. The bearing part 9 of the present embodiment has a first journal bearing 91, a second journal bearing 92, and a thrust bearing 93.

[0052] The first journal bearing 91 rotatably supports the first supported portion 52. The first journal bearing 91 receives a radial load Dr acting on the end of the rotor 3 on the first side Da1 in the axial direction Da. The first journal bearing 91 is arranged at a position overlapping the first supported portion 52 in the axial direction Da. The first journal bearing 91 is arranged at a position closer to the first enlarged diameter portion 53 than the thrust collar 511 in the axial direction Da.

[0053] The second journal bearing 92 rotatably supports the second shaft portion 61. The second journal bearing 92 receives a radial load Dr acting on the end of the rotor 3 on the second side Da2 in the axial direction Da. The second journal bearing 92 is attached inside the cylindrical bearing holder 95. The second journal bearing 92 is arranged at a position overlapping the second shaft portion 61 in the axial direction Da.

[0054] The thrust bearing 93 rotatably supports the thrust collar 511 of the first shaft portion 51. The thrust bearing 93 receives an axial load Da acting on the rotor 3. The thrust bearing 93 is attached inside the box-shaped bearing cover 96 together with the first journal bearing 91. The thrust bearing 93 is arranged at a position overlapping the thrust collar 511 in the axial direction Da.

[0055] (Configuration of squeeze film damper) The squeeze film damper 350 is capable of suppressing the vibration of the rotor 3 indirectly through a fluid. The squeeze film damper 350 is disposed at the end of the rotor 3. The squeeze film damper 350 is disposed at the end of the rotor 3 that is not connected to other rotating machines including the drive machine 200 and the transmission 300 in the rotor 3. The squeeze film damper 350 is disposed at the end of the rotor 3 at a position far from the drive machine 200 in the axial direction Da. That is, the squeeze film damper 350 is disposed at the end of the rotor 3 on the first side Da1 of the axial direction Da that is not connected to the transmission rotor 310. That is, the squeeze film damper 350 supports the end of the first shaft portion 51 in the axial direction Da. The squeeze film damper 350 is disposed on the side opposite to the first journal bearing 91 with respect to the thrust bearing 93 in the axial direction Da.

[0056] Further, the squeeze film damper 350 is a damper that supplies oil from the outside between the outer peripheral surface of the end of the rotor 3, and generates a resistance force against the vibration of the rotor 3 by the flow and compression of the oil to attenuate the vibration. The squeeze film damper 350 of the present embodiment has an inner member 351, a seal member 352, and a lid member 353, as shown in FIG. 3.

[0057] The inner member 351 supports the rotor 3. The inner member 351 supports the first shaft portion 51 at the position on the second side Da2 closest to the rotor 3 in the axial direction Da. The inner member 351 is an annular or cylindrical member centered on the axis O. An oil supply hole 351a penetrating in the radial direction Dr is formed in the inner member 351. The oil supply hole 351a supplies the oil supplied from the outside to the outer peripheral surface of the first shaft portion 51. The inner member 351 is fixed to the bearing cover 96.

[0058] The seal member 352 seals between the inner member 351 and the bearing cover 96. The seal member 352 is an annular O-ring centered on the axis O. A pair of seal members 352 are arranged apart from each other in the axial direction Da with the oil supply hole 351a interposed therebetween.

[0059] The cover member 353 covers the end portion and the inner member 351 of the rotor 3. The cover member 353 is detachable from the bearing cover 96. By being attached to the bearing cover 96, the cover member 353 covers the end face of the rotor 3 from the first side Da1 in the axial direction Da.

[0060] (Configuration of the first coupling) As shown in FIG. 1, the first coupling 410 connects the transmission 300 and the drive machine 200. The first coupling 410 connects the end portion of the transmission rotor 310 and the end portion of the drive shaft 210.

[0061] (Configuration of the second coupling) The second coupling (coupling) 420 connects the transmission 300 and the compressor 100. The second coupling 420 connects the end portion of the transmission rotor 310 on the first side Da1 in the axial direction Da and the end portion of the rotor 3 on the second side Da2 in the axial direction Da. As shown in FIG. 4, the second coupling 420 includes a transmission-side coupling member 421 and a compressor-side coupling member 422.

[0062] The transmission-side coupling member 421 is fixed to the end portion of the transmission rotor 310 on the first side Da1 in the axial direction Da. The transmission-side coupling member 421 is fixed to the transmission rotor 310 by hydraulic fitting, shrink fitting, or the like.

[0063] The compressor-side coupling member 422 is fixed to the end portion of the rotor 3 on the second side Da2 in the axial direction Da. The compressor-side coupling member 422 is connected to the rotor 3 by a spline structure. The compressor-side coupling member 422 is fixed to the second shaft portion 61. That is, the second shaft portion 61 with external teeth and the compressor-side coupling member 422 with internal teeth are meshed and connected. Also, in the axial direction Da, the distance between the end portion of the transmission rotor 310 and the end portion of the rotor 3 is set to 400 mm or less. That is, the end face of the second shaft portion 61 is separated from the end face of the transmission rotor 310 by a narrow distance of 400 mm or less on the first side Da1 in the axial direction Da.

[0064] (Function and Effect) In the compressor 100 of the compressor system 1 with the above configuration, in the compressor 100, in order to boost a light gas with a small molecular weight such as hydrogen gas, it is necessary to rotate the rotor 3 at a high speed of 15,000 rpm or more. When the rotor 3 is rotated at a high speed of 15,000 rpm or more, the peripheral speed of the impeller 30 becomes 400 m / s or more. In order to increase the peripheral speed of the impeller 30, it is necessary to increase the diameter of the impeller 30. By increasing the diameter of the impeller 30, the axial length of the rotor 3 increases in proportion to the size of the impeller 30. Furthermore, when the rotor 3 with a long axial length is rotated at a high speed, the vibration generated in the rotor 3 becomes large.

[0065] Also, the diameter of the region supported by the first journal bearing 91 is set to 120 mm or less. That is, the size of the first journal bearing 91 that supports the rotor 3 becomes small. With such a small first journal bearing 91, the vibration of the rotor 3 rotating at a high speed of 15,000 rpm or more cannot be sufficiently suppressed.

[0066] Furthermore, since the rotor 3 is configured by arranging and fixing a plurality of impellers 30 having a solid structure, the thrust force generated in the thrust bearing 93 becomes large. Therefore, it is necessary to increase the thrust collar 511. In the present embodiment, furthermore, the diameter of the thrust collar 511, which is the region supported by the thrust bearing 93, is formed larger than 120 mm, which is the diameter of the region supported by the first journal bearing 91. Therefore, the weight of the first shaft portion 51 on which the thrust collar 511 is formed increases, the vibration at the end of the first shaft portion 51 becomes larger, and the vibration of the entire rotor 3 also becomes larger.

[0067] Thus, in the rapidly rotating rotor 3, vibrations increase due to various factors. In contrast, a squeeze film damper 350 is disposed at an end portion of the drive machine 200 of the rotor 3 in which a plurality of solid impellers 30 are arranged and fixed, at a position far in the axial direction Da. That is, the vibration of the end portion of the first shaft portion 51 not connected to other rotating machines is suppressed by the squeeze film damper 350. In particular, by using the squeeze film damper 350, the vibration of the end portion of the first shaft portion 51 is suppressed by using oil without direct contact, so that the destabilizing force generated at the end portion of the first shaft portion 51 can be reduced with high accuracy regardless of the type of the bearing portion 9. Thereby, the vibration of the rapidly rotating rotor 3 can be stably suppressed.

[0068] Also, the squeeze film damper 350 is disposed on the side opposite to the first journal bearing 91 with respect to the thrust bearing 93 in the axial direction Da. In the rotor 3, the region on the side opposite to the first journal bearing 91 with respect to the thrust bearing 93 is a free end. Specifically, the end portion of the first shaft portion 51 in the region Da1 on the first side in the axial direction Da from the region supported by the first journal bearing 91 and the thrust bearing 93 is a free end not connected to other machines such as the transmission 300. Therefore, it is a region where the vibration is particularly large among the rotors 3. By disposing the squeeze film damper 350 in such a region, the vibration of the rotor 3 can be suppressed at the position where the vibration is the largest. Thereby, the vibration of the rapidly rotating rotor 3 can be effectively suppressed only by the squeeze film damper 350.

[0069] Also, the impeller 30 has a solid structure. That is, the impeller 30 is not structured to be fixed to the outer peripheral surface of the shaft by shrink fitting or the like. Therefore, a large hole for inserting the shaft is not formed at the center of the impeller 30. Since there is no large hole in the impeller 30, when the rotor 3 is rotated, the strength of the impeller 30 against the load generated by the centrifugal force can be greatly improved.

[0070] In addition, a balance piston portion 62 is disposed on the second side Da2 in the axial direction Da with respect to the plurality of impellers 30. Therefore, the thrust force acting on the rotor 3 from the second side Da2 to the first side Da1 in the axial direction Da can be reduced by the balance piston. As a result, the size of the thrust collar 511 can be suppressed. Accordingly, the weight of the first shaft portion 51 formed with the thrust collar 511 is reduced, and the vibration at the end of the first shaft portion 51 can be suppressed. Thereby, the vibration of the high-speed rotating rotor 3 can be suppressed at the end of the first shaft portion 51.

[0071] In addition, the compressor-side coupling member 422 of the second coupling 420 is connected to the second shaft portion 61 by a spline structure. Since the compressor-side coupling member 422 is connected by a spline structure without using hydraulic pressure, friction, etc., the compressor-side coupling member 422 and the second shaft portion 61 are connected in a state of being physically in contact with each other in the circumferential direction Dc. Therefore, even when the required power is very high, 1000 kw or more, and the rotational speed is 15000 rpm or more, the connection between the second shaft portion 61 with a small diameter and the compressor-side coupling member 422 can be stably ensured. Further, by connecting in a state of being physically in contact with each other in the circumferential direction Dc, even if the compressor-side coupling member 422 is lightened, the connection with the compressor-side coupling member 422 can be stably ensured.

[0072] In addition, the end face of the second shaft portion 61 in the axial direction Da is located at a narrow interval of 400 mm or less on the first side Da1 in the axial direction Da with respect to the end face of the transmission rotor 310. This axial end distance of 400 mm or less is a value below the API standard determined for attaching and detaching the compressor-side coupling member 422 to the rotor 3. By narrowing the axial end distance between the rotor 3 and the transmission rotor 310 in this way, the size of the second coupling 420 can be suppressed. As a result, the load generated on the second shaft portion 61 is reduced, and the vibration at the end of the second shaft portion 61 can be suppressed. Thereby, the vibration of the high-speed rotating rotor 3 can be suppressed at the end of the second shaft portion 61.

[0073] (Other Embodiments) As described above, the embodiments of the present disclosure have been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like within the scope not departing from the gist of the present disclosure are also included.

[0074] Note that the structure of the rotor 3 is not limited to the above structure as long as it can rotate at high speed. That is, the structure and shape of the impeller 30, the first shaft end member 50, and the second shaft end member 60 of the rotor 3 may be different.

[0075] Also, the structure of the squeeze film damper 350 is not limited to the structure as long as it can suppress the vibration of the rotor 3 indirectly via a fluid at the end of the rotor 3.

[0076] Moreover, the compressor system 1 is not limited to a structure that necessarily includes the transmission 300. The compressor system 1 may be, for example, a structure in which the compressor 100 and the drive machine 200 are directly connected. In that case, it is preferable that the coupling connecting the compressor 100 and the drive machine 200 has the same structure as the second coupling 420.

[0077] <Supplementary Note> The compressor 100 and the compressor system 1 described in the embodiment are understood, for example, as follows.

[0078] (1) The compressor 100 according to the first aspect includes a rotor 3 rotatable about an axis O, a casing 2 covering the rotor 3 from the outside Dro in the radial direction Dr with respect to the axis O, and a squeeze film damper 350 disposed at an end of the rotor 3 and capable of indirectly suppressing vibration of the rotor 3 via a fluid. The rotor 3 is formed in a disk shape centered on the axis O and has a solid structure with a filled center. The rotor 3 has a plurality of impellers 30 adjacent to the axial direction Da in which the axis O extends, and a bolt fixing portion 70 having a plurality of bolts 71 that collectively fix the plurality of impellers 30 arranged in the axial direction Da. The squeeze film damper 350 is disposed at an end of the rotor 3 that is not connected to other rotating machines in the axial direction Da.

[0079] As a result, in the rotor 3, vibration at the end not connected to other rotating machines is suppressed by the squeeze film damper 350. By using the squeeze film damper 350, the vibration at the end of the rotor 3 is suppressed using oil without direct contact, so that the destabilizing force generated at the end of the rotor 3 can be reduced with high accuracy regardless of the type of the bearing portion 9. Thereby, vibration of the high-speed rotating rotor 3 can be stably suppressed.

[0080] (2) The compressor 100 according to the second aspect is the compressor 100 according to (1), further including a bearing portion 9 that rotatably supports the rotor 3 with respect to the casing 2. The bearing portion 9 has a first journal bearing 91 and a second journal bearing 92 disposed apart from each other in the axial direction Da, and a thrust bearing 93 disposed on the side opposite to the second journal bearing 92 with respect to the first journal bearing 91 in the axial direction Da. The squeeze film damper 350 is disposed on the side opposite to the first journal bearing 91 with respect to the thrust bearing 93 in the axial direction Da.

[0081] In the rotor 3, the region on the side opposite to the first journal bearing 91 with respect to the thrust bearing 93 is a free end. Therefore, it is a region where the vibration is particularly large among the rotors 3. By disposing the squeeze film damper 350 in such a region, the vibration of the rotor 3 can be suppressed at the position where the vibration is the largest. Thereby, the vibration of the high-speed rotating rotor 3 can be effectively suppressed only by the squeeze film damper 350.

[0082] (3) The compressor system 1 according to the third aspect includes the compressor 100 of (1) or (2) that compresses the working fluid, and a drive machine 200 that has a drive shaft 210 that rotates around the axis O and drives the compressor 100. The squeeze film damper 350 is disposed at the end of the rotor 3 at a position far from the drive machine 200 in the axial direction Da.

[0083] (4) The compressor system 1 according to the third aspect is the compressor system 1 of (3), and between the drive machine 200 and the compressor 100 in the axial direction Da, a transmission 300 that changes the rotation of the drive machine 200 and transmits it to the compressor 100 via the transmission rotor 310, and a coupling that connects the transmission rotor 310 and the rotor 3 are further provided. The coupling is connected to the rotor 3 in a spline structure.

[0084] Thereby, since the coupling is connected in a spline structure without using hydraulic pressure, friction, etc., the coupling and the end of the rotor 3 are connected in a state of being physically in contact in the circumferential direction Dc. Therefore, the connection between the rotor 3 and the coupling can be stably ensured.

Explanation of Signs

[0085] 1... Compressor system O... Axis 200... Drive machine 210... Drive shaft 300... Transmission 310... Transmission rotor 100... Compressor 10…Bundle 2…Casing 21…Outer Casing 211…End Plate 212…Insertion Hole 22…Diaphragm 221…Suction Port 222…Casing Flow Path 223…Discharge Port 23…Head 231…Suction Side Head 232…Discharge Side Head 3…Rotor 30…Impeller 301…Impeller Flow Path 38…Bolt Hole 41…Impeller Shaft Portion 42…Impeller Outer Periphery 5…Shaft End Member 50…First Shaft End Member 51…First Shaft Portion 511…Thrust Collar 52…First Supported Portion 53…First Enlarged Diameter Portion 531…First Nut Accommodation Recess 532…First Shaft End Bolt Hole 60…Second Shaft End Member 61…Second Shaft Portion 62…Balance Piston Portion 621…Second Nut Accommodation Recess 622…Second Shaft End Bolt Hole 70…Bolt Fixing Portion 71…Bolt 72…Nut 8…Seal Portion 8A…First Seal Portion 8B…Second Seal Portion 8C…Third Seal Portion 9…Bearing Portion 91…First Journal Bearing 92…Second Journal Bearing 93…Thrust Bearing 95…Bearing Holder 96…Bearing Cover 350…Squeeze Film Damper 351…Inner Member 351a…Oil supply hole 352…Sealing member 353…Cover member 410…First coupling 420…Second coupling 421…Transmission side coupling member 422…Compressor side coupling member Da…Axial direction Da1…First side Da2…Second side Dc…Circumferential direction Dr…Radial direction Dri…Inner side Dro…Outer side

Claims

1. a rotor that is rotatable around an axis; a casing that covers the rotor from the outside in a radial direction relative to the axis; a squeeze film damper disposed at an end of the rotor and capable of indirectly suppressing vibration of the rotor via a fluid, The rotor is a plurality of impellers each having a disk-like shape centered on the axis line and a solid structure with a filled center, the impellers being adjacent to each other in an axial direction in which the axis line extends; a bolt fixing portion having a plurality of bolts that fix together the plurality of impellers that are arranged in the axial direction, the squeeze film damper is disposed in the axial direction at an end of the rotor that is not connected to another rotating machine; a balance piston portion disposed at an end of the rotor opposite the squeeze film damper in the axial direction.

2. a bearing portion that rotatably supports the rotor relative to the casing, The bearing portion is a first journal bearing and a second journal bearing arranged axially apart from each other; a thrust bearing disposed on an opposite side of the second journal bearing with respect to the first journal bearing in the axial direction, 2. The compressor according to claim 1, wherein the squeeze film damper is disposed on an opposite side of the thrust bearing from the first journal bearing in the axial direction.

3. The compressor according to claim 1 or 2, which compresses a working fluid; a drive machine having a drive shaft that rotates about an axis and that drives the compressor, The squeeze film damper is disposed at an end of the rotor that is axially remote from the driver.

4. a transmission arranged between the driver and the compressor in the axial direction, which changes the rotation of the driver and transmits the rotation to the compressor via a transmission rotor; a coupling that connects the transmission rotor and the rotor, The compressor system according to claim 3 , wherein the coupling is connected to the rotor by a spline structure.

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