(19)
(11)EP 3 339 655 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
02.10.2019 Bulletin 2019/40

(21)Application number: 15908330.2

(22)Date of filing:  13.11.2015
(51)Int. Cl.: 
F04D 17/12  (2006.01)
F04D 29/10  (2006.01)
F04D 29/58  (2006.01)
F04D 29/42  (2006.01)
(86)International application number:
PCT/JP2015/081965
(87)International publication number:
WO 2017/081810 (18.05.2017 Gazette  2017/20)

(54)

CENTRIFUGAL COMPRESSOR WITH HEAT SHIELD FOR PROTECTING BEARINGS AND SEALS

ZENTRIFUGALVERDICHTER MIT HITZESCHILD ZUM SCHUTZ VON DICHTUNGEN UND LAGERN

COMPRESSEUR CENTRIFUGE AVEC ÉCRAN THERMIQUE POUR LA PROTECTION DE JOINTS D'ÉTANCHÉITÉ ET PALIERS


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(43)Date of publication of application:
27.06.2018 Bulletin 2018/26

(73)Proprietor: Mitsubishi Heavy Industries Compressor Corporation
Minato-ku Tokyo 108-0014 (JP)

(72)Inventors:
  • YANAGISAWA, Eiichi
    Tokyo 108-8215 (JP)
  • YOKOO, Kazutoshi
    Tokyo 108-8215 (JP)
  • OKADA, Noriyuki
    Tokyo 108-8215 (JP)
  • MASUDA, Yuji
    Hiroshima-shi Hiroshima 733-8553 (JP)
  • TOKUYAMA, Shinichiro
    Hiroshima-shi Hiroshima 733-8553 (JP)

(74)Representative: Studio Torta S.p.A. 
Via Viotti, 9
10121 Torino
10121 Torino (IT)


(56)References cited: : 
WO-A2-2014/187786
JP-A- 2008 138 577
JP-A- 2013 513 064
JP-U- S54 132 809
US-A- 3 758 226
US-A1- 2013 058 769
DE-A1-102012 203 144
JP-A- 2012 177 339
JP-U- S5 455 505
JP-U- S54 132 809
US-A- 3 976 165
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    [Technical Field]



    [0001] The present invention relates to a centrifugal compressor that compresses a fluid using an impeller.

    [Background Art]



    [0002] As is well known, centrifugal compressors pass a fluid such as air or gas in a radial direction of a rotating impeller, and compress the fluid using a centrifugal force generated at that time. Among these centrifugal compressors, a multistage centrifugal compressor that includes impellers in multiple stages in a direction of an axis and gradually compresses a fluid is known.

    [0003] To be specific, the centrifugal compressor includes a casing, and a rotor housed in the casing. The rotor has a shaft and an impeller fixed to an outer surface of the shaft. A fluid suctioned from a suction port of the casing is given a centrifugal force by the impeller, and kinetic energy thereof is converted into pressure energy by a diffuser and a scroll part. The fluid is sent out of a discharge port of the casing.

    [0004] According to the requirements of various plants, various centrifugal compressors are produced. In recent years, a centrifugal compressor for compressing a fluid of ultralow temperature (e.g., -160°C) has been developed, for example, as a compressor for an LNG boil off gas (e.g., see Japanese Patent No. 4980699).

    [0005] Other known systems are disclosed in documents DE102012203144 A1, US3976165 A, US2013/058769 A1 or JPS54123809 U.

    [Summary of Invention]


    [Technical Problem]



    [0006] Meanwhile, for example, in the centrifugal compressor for compressing the cryogenic fluid, when the fluid was suctioned, a casing head adjacent to a suction port was sometimes deformed due to an excessive change in temperature. As the casing head was deformed, a function of a seal device for sealing a space between the casing head and a rotor was not sufficiently fulfilled. Due to the deformation of the casing head, there was a possibility of failure of a bearing that was installed on the casing head and rotatably supported the rotor.

    [0007] An object of the present invention is to provide a centrifugal compressor capable of inhibiting failure from occurring at a seal device and a bearing device.

    [Solution to Problem]



    [0008] The solution to the aforementioned problem is reached by a centrifugal compressor as claimed in the appended set of claims.

    [0009] According to the claimed constitution, heat of the fluid flowing along the suction flow passage is hardly transferred to the first casing head by the insulating space, and the first casing head can be inhibited from being deformed by heat. Thereby, failure can be inhibited from occurring at the seal device and the bearing device.

    [0010] Further , even when the shield part is deformed by the heat of the fluid flowing along the suction flow passage, stress occurring at the shield part can be relieved, compared to a case in which an inner side of the shield part in the radial direction is fixed.

    [0011] Further, the first casing head can be heated or cooled according to a temperature of the fluid flowing to the suction flow passage. Thereby, even which the heat of the fluid flowing along the suction flow passage is transferred to the first casing head, thermal deformation of the first casing head can be limited.

    [0012] Further, the heat of the fluid flowing to the discharge flow passage is not easily transferred to the second casing head, and the second casing head can be inhibited from being deformed by heat. Thereby, failure can be inhibited from occurring at the discharge side bearing device.

    [0013] Further, the heat of the fluid flowing to the suction flow passage and the discharge flow passage cannot be easily transferred to the first casing head.

    [0014] Further, the insulating space and the suction flow passage can be completely interrupted. In addition, rigidity of the shield part can be further enhanced.

    [0015] Further, a sealing degree of the insulating space can be improved.

    [Advantageous Effects of Invention]



    [0016] Further, due to an insulating space, heat of a fluid flowing to a suction flow passage is not easily transferred to a first casing head, and the first casing head can be inhibited from being deformed by the heat. Thereby, failure can be inhibited from occurring at a seal device and a bearing device.

    [Brief Description of Drawings]



    [0017] 

    Fig. 1 is a sectional view showing a constitution of a centrifugal compressor of a first embodiment of the present invention.

    Fig. 2 is a sectional view around a suction port of the centrifugal compressor of the first embodiment of the present invention.

    Fig. 3 is a sectional view around a discharge port of the centrifugal compressor of the first embodiment of the present invention.

    Fig. 4 is a sectional view around a suction port of a centrifugal compressor of a second embodiment of the present invention.

    Fig. 5 is a sectional view around the suction port of the centrifugal compressor of the second embodiment of the present invention.


    [Description of Embodiments]



    [0018] Embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiments, a multistage centrifugal compressor having a plurality of impellers will be described as an example of a centrifugal compressor.

    [0019] As shown in Fig. 1, a centrifugal compressor 1 of the present embodiment includes a casing 2, and a rotor 7 that is rotatably supported in the casing 2. The rotor 7 has a shaft 8 that extends along an axis A, and a plurality of impellers 9 that are fixed to an outer surface of the shaft 8.

    [0020] In the following description, a direction in which the axis A of the rotor 7 extends is defined as an axial direction Da. A direction orthogonal to the axis A is defined as a radial direction. A side away from the axis A in the radial direction is referred to as an outer side in the radial direction, and a side close to the axis A in the radial direction is referred to as an inner side in the radial direction. The right side of Fig. 1 in the axial direction Da is referred to as a first side Da1 in the axial direction, and the left side of Fig. 1 is referred to as a second side Da2 in the axial direction.

    [0021] The casing 2 has a diaphragm 3 that surrounds the impellers 9 from outer circumferential sides thereof, a first casing head 4 that is disposed at the second side Da2 in the axial direction of the diaphragm 3 at an interval, a second casing head 5 that is disposed at the first side Da1 in the axial direction of the diaphragm 3 at an interval, and a shield plate (a shield part) 11 that is fixed to the first casing head 4.

    [0022] The diaphragm 3 has a structure in which a plurality of diaphragm segments 6 are arranged in the axial direction Da.

    [0023] The impellers 9 are mounted on an outer surface of the shaft 8, and feed a fluid G such as air, which flows from the second side Da2 in the axial direction to the first side Da1 in the axial direction, toward the outer side in the radial direction under pressure using a centrifugal force.

    [0024] The casing 2 rotatably supports the rotor 7. The casing 2 is formed with a flow passage 12 that causes the fluid G to flow from an upstream side (the second side Da2 in the axial direction) to a downstream side (the first side Da1 in the axial direction).

    [0025] The casing 2 is formed to have an approximately columnar contour, and the rotor 7 is disposed to pass through the center of the casing 2. The first casing head 4 is provided with a first journal bearing 13 that is a bearing device for rotatably supporting an end of the rotor 7 at the second side Da2 in the axial direction. The first journal bearing 13 is fixed to the first casing head 4. A thrust bearing 15 is provided at the second side Da2 in the axial direction of the first journal bearing 13.

    [0026] A dry gas seal 16 is provided at the inner side in the radial direction of the first casing head 4. The dry gas seal 16 is provided at the first side Da1 in the axial direction of the first journal bearing 13. The dry gas seal 16 is a seal device that performs sealing by ejecting a gas such as dry gas. The seal device is not limited to the dry gas seal 16, and anything that can seal a clearance between the first casing head 4 and the shaft 8 may be properly adopted. For example, as the seal device, a labyrinth seal may be installed between the first casing head 4 and the shaft 8.

    [0027] A seal fin 30 having a plurality of fins is provided at the first side Da1 in the axial direction of the dry gas seal 16.

    [0028] A second journal bearing (a discharge side bearing device) 14 for rotatably supporting an end of the rotor 7 at the first side Da1 in the axial direction is provided at the inner side in the radial direction of the second casing head 5. The second journal bearing 14 is fixed to the second casing head 5.

    [0029] A suction port (a suction flow passage) 18 for introducing the fluid G from the outside is provided at an end of the casing 2 at the second side Da2 in the axial direction. The suction port 18 is defined by the shield plate 11 and the diaphragm 3.

    [0030] A discharge port (a discharge flow passage) 19 through which the fluid G is discharged to the outside is provided at an end of the casing 2 at the first side in the axial direction. The discharge port 19 is defined by a discharge side shield member 64 and the diaphragm 3.

    [0031] An internal space 20 which communicates the suction port 18 and the discharge port 19 and in which decrease and increase in diameter is repeated is provided in the casing 2. The internal space 20 functions as a space for housing the impellers 9, and also functions as the flow passage 12 described above. That is, the suction port 18 and the discharge port 19 communicate via the impellers 9 and the flow passage 12.

    [0032] The plurality of impellers 9 are arranged at intervals in the axial direction Da. The number of provided impellers 9 is six in the shown example, but it may be at least one. As shown in Fig. 2, each of the impellers 9 is made up of an approximately discoid hub 22 whose diameter is gradually increased toward the first side Da1 in the axial direction, a plurality of blades 23 that are radially mounted on the hub 22 and are arranged in a circumferential direction, and a shroud 24 that is mounted to cover tip sides of the plurality of blades 23 in the circumferential direction.

    [0033] The flow passage 12 is formed to connect the impellers 9 by running in the axial direction Da while meandering in the radial direction such that the fluid G is compressed step by step by the plurality of impellers 9. The flow passage 12 is mainly made up of a suction passage 25, a compression passage 26, a diffuser passage 27, and a return passage 28.

    [0034] A discharge scroll 29 (see Fig. 1) for discharging the fluid G from a discharge port is provided in the casing 2.

    [0035] An oil heater 60 that is a temperature regulator for heating the first casing head 4 is provided for the first casing head 4. The oil heater 60 has a pipe line 61 that is formed inside the first casing head 4, an oil heater main body (a temperature regulator main body) 62 that is connected to the pipe line 61, and a heat medium that is introduced into the oil heater main body 62 via the pipe line 61.

    [0036] The pipe line 61 is connected to a heat medium supply source (not shown). The oil heater main body 62 has an annular shape, and is formed to surround the rotor 7. A heat medium flow passage 63 through which the heat medium supplied via the pipe line 61 circulates is formed in the oil heater main body 62. For example, a lubricant supplied to the journal bearings 13 and 14 as the heat medium can be supplied to the oil heater 60. The first casing head 4 can be heated or cooled by changing the temperature of the heat medium.

    [0037] Next, a detailed structure of the suction port 18 of the centrifugal compressor 1 of the present embodiment will be described.

    [0038] As shown in Fig. 2, the second side Da2 in the axial direction of the suction port 18 is formed by the shield plate 11 fixed to the first casing head 4, and the first side Da1 in the axial direction of the suction port 18 is formed by an end face 3a of the diaphragm 3. An insulating space 10 is formed between the shield plate 11 and the first casing head 4.

    [0039] An end face (a head end face 4a) of the first casing head 4 which faces the first side Da1 in the axial direction is an annular face that extends in a circumferential direction. The head end face 4a has a first planar part 31 that is located at the outer side in the radial direction and is a face perpendicular to the axis A, a conical first incline part 32 which is located at the inner side in the radial direction of the first planar part 31 and whose diameter is reduced toward the first side Da1 in the axial direction, a second planar part 33 that is located at the inner side in the radial direction of the first incline part 32 and is a face perpendicular to the axis A, and a conical second incline part 34 which is located at the inner side in the radial direction of the second planar part 33 and whose diameter is reduced toward the first side Da1 in the axial direction.

    [0040] The first incline part 32 and the second planar part 33 are connected by a cylindrical part 35 having a cylindrical shape that is coaxial with the axis A.

    [0041] An outer edge protrusion 36 is formed at an end of the first planar part 31 at the outer side in the radial direction. The outer edge protrusion 36 is an annular protrusion that protrudes from the end of the first planar part 31 at the outer side in the radial direction to the first side Da1 in the axial direction. The outer edge protrusion 36 has a protrusion principal surface 37 that is a surface parallel to a principal surface of the first planar part 31 and is offset to the first side Da1 in the axial direction with respect to the principal surface of the first planar part 31.

    [0042] The shield plate 11 is an annular plate-like member that extends in a circumferential direction. The shield plate 11 has a fixing part 40 that is located at the outer side in the radial direction, a first disk part 41 that is formed at the first side Da1 in the axial direction of the fixing part 40, a first conical part 42 that is connected to the inner side in the radial direction of the first disk part 41, a second disk part 43 that is connected to the inner side in the radial direction of the first conical part 42, and a second conical part 44 that is connected to the inner side in the radial direction of the second disk part 43.

    [0043] The shield plate 11 is fixed to the first planar part 31 of a head incline via the fixing part 40. The shield plate 11 has a cantilever structure that is fixed to the first planar part 31 by only the fixing part 40. The inner side in the radial direction of the shield plate 11 is a free end, and is not fixed. A clearance C is provided between an end of the shield plate 11 at the inner side in the radial direction and an outer circumferential surface of the shaft 8.

    [0044] A principal surface of the first disk part 41 is perpendicular to the axis A. The first conical part 42 has a conical shape whose diameter is reduced toward the first side Da1 in the axial direction. A principal surface of the second disk part 43 is perpendicular to the axis A. The second conical part 44 has a conical shape whose diameter is reduced toward the first side Da1 in the axial direction.

    [0045] The fixing part 40 is an annular part that extends in a circumferential direction and has a rectangular cross section. A plurality of through-holes 56 penetrating in the axial direction Da are formed in the fixing part 40 (only one through-hole 56 is shown in Fig. 2). The plurality of through-holes 56 are formed at regular intervals in the circumferential direction. The shield plate 11 is fixed to the first planar part 31 by fastening bolts 57 inserted into the through-holes 56 in female threaded holes formed in the first planar part 31.

    [0046] An annular convex part 45 is formed on a fixing part principal surface 46 that is a surface of the fixing part 40 which faces the second side Da2 in the axial direction. The annular convex part 45 is an annular protrusion that protrudes from the fixing part principal surface 46 to the second side Da2 in the axial direction. The annular convex part 45 has an annular convex part principal surface 45a that is a surface parallel to the fixing part principal surface 46 and is offset to the second side Da2 in the axial direction with respect to the fixing part principal surface 46.

    [0047]  The fixing part 40 of the shield plate 11 and the first planar part 31 of the first casing head 4 are connected in a so-called pillbox structure. In detail, the annular convex part 45 having a smaller outer diameter than the first casing head 4 is formed at the fixing part 40 of the shield plate 11. The outer edge protrusion 36 that is an annular protrusion is formed at the first planar part 31 of the head end face 4a.

    [0048] An outer circumferential surface 47 of the annular convex part 45 and an inner circumferential surface 38 of the outer edge protrusion 36 are in surface contact with each other. That is, the annular convex part 45 is fitted to the inner side in the radial direction of the outer edge protrusion 36, and thereby the shield plate 11 is positioned. The amount of protrusion of the annular convex part 45 from the fixing part principal surface 46 is equal to an amount of protrusion of the outer edge protrusion 36 from the first planar part 31. Thereby, the fixing part principal surface 46 of the fixing part 40 and the protrusion principal surface 37 of the first planar part 31 are in surface contact with each other, and the annular convex part principal surface 45a of the fixing part 40 and the first planar part 31 are in surface contact with each other.

    [0049] A seal ring 58 is provided for the first planar part 31 facing the annular convex part principal surface 45a of the annular convex part 45. That is, the seal ring 58 fitted into an annular groove formed in the first planar part 31 is in close contact with the annular convex part principal surface 45a.

    [0050] An annular space is formed between the head end face 4a of the first casing head 4 and the shield plate 11. Hereinafter, this annular space is referred to as the insulating space 10.

    [0051] An insulator 49 that reduces transfer of heat of the shield plate 11 to the first casing head 4 is filled in the insulating space 10 without a clearance. In an example which does not form part of the present invention, the insulator 49 does not essentially need to be filled.

    [0052] The first incline part 32 of the head end face 4a and the first conical part 42 of the shield plate 11 are disposed in parallel at a predetermined interval in the axial direction Da. The space between the first incline part 32 and the first conical part 42 is referred to as a first insulating space 51. The interval between the first incline part 32 and the first conical part 42 is referred to as a first interval S1.

    [0053] Likewise, a space between the second planar part 33 and the second disk part 43 is referred to as a second insulating space 52. The interval between the second planar part 33 and the second disk part 43 is referred to as a second interval S2.

    [0054] A first narrow part 53 at which an interval between the shield plate 11 and the head end face 4a is formed to be narrower than the first interval S1 and the second interval S2 is provided between the first insulating space 51 and the second insulating space 52.

    [0055] A second narrow part 54 at which the interval between the shield plate 11 and the head end face 4a is formed to be narrower than the first interval S1 and the second interval S2 is provided between the second insulating space 52 and the clearance C.

    [0056] The interval between the shield plate 11 and the head end face 4a at the first narrow part 53 is referred to as a third interval S3.

    [0057] The interval between the shield plate 11 and the head end face 4a at the second narrow part 54 is referred to as a fourth interval S4.

    [0058] The dimensions of the third interval S3, the fourth interval S4, and the clearance C are approximately the same. That is, the dimensions of the third interval S3, the fourth interval S4, and the clearance C are sufficiently smaller than the first interval S1 and the second interval S2.

    [0059] Next, the detailed structure of the discharge port 19 of the centrifugal compressor 1 of the present embodiment will be described.

    [0060] As shown in Fig. 3, the first side Da1 in the axial direction of the discharge port 19 is defined by the discharge side shield member 64 fixed to the second casing head 5, and the first side Da1 in the axial direction of the discharge port 19 is defined by the end face 3b of the diaphragm 3. A discharge side insulating space 65 is formed between the discharge side shield member 64 and the first casing head 4.

    [0061] The discharge side shield member 64 is fixed to the second casing head 5 by welding. The discharge side insulating space 65 is sealed by a weld zone 66.

    [0062] The discharge side shield member 64 is a block-like member formed in an annular shape. An interval (a fifth interval S5) between the discharge side shield member 64 and the second casing head 5 is uniformly formed. The dimension of the fifth interval S5 may be set to be equal to, for instance, the third interval S3 or the fourth interval S4 (see Fig. 2).

    [0063] The dimension of the fifth interval S5 is not limited thereto, and may be set to be equal to the first interval S1, and the insulator 49 may be filled in the discharge side insulating space 65.

    [0064] According to the above embodiment, heat of the fluid G flowing along the suction port 18 is hardly transferred to the first casing head 4 by the insulating space 10, and the first casing head 4 can be inhibited from being deformed by heat.

    [0065] Thereby, failure can be inhibited from occurring at the dry gas seal 16 and the first journal bearing 13. That is, the first casing head 4 is deformed, and an influence of the deformation can be prevented from being exerted on the dry gas seal 16 installed at the inner side in the radial direction of the first casing head 4. In addition, the first casing head 4 is deformed, and a clearance of the first journal bearing 13 installed at the inner side in the radial direction of the first casing head 4 can be inhibited from being changed.

    [0066] The narrow parts 53 and 54 are provided, and thereby work of filling the insulator 49 in the insulating space 10 can be facilitated. That is, the narrow parts 53 and 54 are provided, and thereby the insulator 49 can be reliably held.

    [0067] The shield plate 11 is formed in the cantilever structure, and the clearance C is provided between the shield plate 11 and the shaft 8. Thereby, in comparison with the case in which the inner side in the radial direction of the shield plate 11 is fixed, even when the shield plate 11 is deformed by the heat of the fluid G flowing along the suction port 18, stress occurring at the shield plate 11 can be relieved. That is, when the end of the shield plate 11 at the outer side in the radial direction and the end of the shield plate 11 at the inner side in the radial direction are fixed, stress occurs inside the shield plate 11 along with thermal deformation of the shield plate 11. However, the shield plate 11 is formed in the cantilever structure, and thereby occurrences of the stress can be limited.

    [0068] The shield plate 11 is fixed using the pillbox structure, and thereby centering of the shield plate 11 during mounting can be facilitated. That is, the clearance C between the shield plate 11 and the shaft 8 can be made constant.

    [0069] The oil heater 60 is provided for the first casing head 4, and thereby the first casing head 4 can be heated. Thereby, the thermal deformation of the first casing head 4 can be limited.

    [0070] A refrigerant flows along the heat medium flow passage 63 of the oil heater 60, and thereby the first casing head 4 can be cooled. That is, the first casing head 4 can be heated or cooled according to the temperature of the fluid G flowing to the suction port 18.

    [0071] The heat of the fluid G flowing to the discharge port 19 is not easily transferred to the second casing head 5 by the discharge side insulating space 65, and the second casing head 5 can be inhibited from being deformed by heat.

    [0072] The above embodiment is configured to include the two narrow parts 53 and 54, but it is not limited thereto. For example, only the second narrow part 54 may be provided to set the insulating space 10 as one space.

    (Second embodiment)



    [0073] Hereinafter, a centrifugal compressor 1B of a second embodiment of the present invention will be described on the basis of the drawings. In the present embodiment, a difference from the aforementioned first embodiment will be mainly described, and a description of the same portions will be omitted.

    [0074] A fixing part 40 of a shield plate 11B and a first planar part 31 of a first casing head 4 in the present embodiment are the same as in the first embodiment, and are connected by a pillbox structure. In the centrifugal compressor 1 of the first embodiment, the part fitted inside is formed at the shield plate 11 side. In contrast, the pillbox structure of the present embodiment is different in that the part fitted inside is formed at the first casing head 4 side.

    [0075] As shown in Fig. 4, a second outer edge protrusion 36B equivalent to the outer edge protrusion 36 of the first embodiment (see Fig. 2) is formed at the fixing part 40 of the present embodiment. An annular concave part 48 corresponding to the second outer edge protrusion 36B is formed in an end of the first planar part 31 of the present embodiment at an outer side in a radial direction. A circumferential surface of the annular concave part 48 at the first planar part 31 is in surface contact with an inner circumferential surface 55 of the second outer edge protrusion 36B.

    [0076] According to the above embodiment, a fluid G introduced from a suction port 18 has a high temperature, and the shield plate 11B is expanded by heat. In this case, the second outer edge protrusion 36B of the fixing part 40 moves to the outer side in the radial direction. Thereby, since the entire shield plate 11B also moves to the outer side in the radial direction, an end of the shield plate 11B at an inner side in the radial direction can be prevented from coming into contact with the shaft 8.

    (Third embodiment)



    [0077] Hereinafter, a centrifugal compressor 1C of a third embodiment of the present invention will be described on the basis of the drawings. In the present embodiment, a difference from the aforementioned first embodiment will be mainly described, and a description of the same portions will be omitted.

    [0078] As shown in Fig. 5, the centrifugal compressor 1C of the present embodiment has a block-shaped first shield member 68 and a block-shaped second shield member 69, each of which is used as a shield part for interrupting heat of a fluid G. That is, the shield parts of the present embodiment have a sufficient thickness in an axial direction Da unlike the plate-like shield plate 11 of the first embodiment. The first shield member 68 is fixed at an outer side in a radial direction of a head end face 4a of a first casing head 4. The second shield member 69 is fixed at an inner side in the radial direction of the head end face 4a.

    [0079] A first insulating space 70 that is a slit-like space extending in a circumferential direction is formed between the first shield member 68 and the first casing head 4. The first insulating space 70 is sealed by a seal ring 72 that is a seal device. That is, the seal ring 72 fitted into an annular groove formed in the head end face 4a is in close contact with a surface of the first shield member 68 which faces the second side Da2 in the axial direction. The first shield member 68 is fixed to the first casing head 4 by bolts 57.

    [0080] A second insulating space 71 extending in the circumferential direction is formed between the second shield member 69 and the first casing head 4. The second shield member 69 is bonded to the first casing head 4 by welding. The outer side in the radial direction of the second insulating space 71 is sealed by a weld zone 73.

    [0081] A method of fixing the first shield member 68 and the second shield member 69 is not limited to the aforementioned method. For example, the first shield member 68 may be fixed to the first casing head 4 by welding.

    [0082] According to this constitution, rigidity of the shield part can be further enhanced. Since the insulating spaces 70 and 71 are sealed by the seal ring 72 or the weld zone 73,
    the insulating spaces 70 and 71 can be kept under vacuum or in a state close to the vacuum.

    [0083] The present embodiment is configured to provide the two shield members and the two insulating spaces, but it is not limited thereto. The present embodiment may be configured to seal one insulating space using one shield member.

    [0084] The embodiments of the present invention have been described in detail, but can be variously modified without departing from the scope of the invention according to the appended set of claims.

    [0085] For example, the above embodiments are also configured to provide the insulating space at the discharge port 19 side, but they are not limited thereto. That is, the discharge side insulating space 65 does not essentially need to be provided.

    [Reference Signs List]



    [0086] 
    1, 1B, 1C
    Centrifugal compressor
    2
    Casing
    3
    Diaphragm
    4
    First casing head
    4a
    Head end face
    5
    Second casing head
    7
    Rotor
    8
    Shaft
    9
    Impeller
    10
    Insulating space
    11, 11B
    Shield plate
    12
    Flow passage
    13
    First journal bearing
    14
    Second journal bearing
    15
    Thrust bearing
    16
    Dry gas seal (seal device)
    18
    Suction port (suction flow passage)
    19
    Discharge port (discharge flow passage)
    20
    Internal space
    30
    Seal fin
    31
    First planar part
    32
    First incline part
    33
    Second planar part
    34
    Second incline part
    35
    Cylindrical part
    36
    Outer edge protrusion
    36B
    Second outer edge protrusion
    37
    Protrusion principal surface
    40
    Fixing part
    41
    First disk part
    42
    First conical part
    43
    Second disk part
    44
    Second conical part
    45
    Annular convex part
    45a
    Annular convex part principal surface
    46
    Fixing part principal surface
    48
    Annular concave part
    49
    Insulator
    51
    First insulating space
    52
    Second insulating space
    53
    First narrow part
    54
    Second narrow part
    60
    Oil heater (temperature regulator)
    62
    Oil heater main body
    64
    Discharge side shield member
    65
    Discharge side insulating space
    66
    Weld zone
    68
    First shield member
    69
    Second shield member
    70
    First insulating space
    71
    Second insulating space
    72
    Seal ring (seal device)
    73
    Weld zone
    A
    Axis
    C
    Clearance
    Da
    Axial direction
    G
    Fluid
    S1
    First interval
    S2
    Second interval
    S3
    Third interval
    S4
    Fourth interval



    Claims

    1. A centrifugal compressor (1, 1B, 1C) comprising:

    a rotor (7) having a shaft (8) that extends along an axis (A) and an impeller (9) that is fixed to an outer surface of the shaft and feeds a fluid (G), which flows into a first side (Da1) in an axial direction (Da) to an outer side in a radial direction of the axis under pressure;

    a diaphragm (3) configured to surround the impeller from an outer circumference side;

    a first casing head (4) disposed at a second side (Da2) of the diaphragm in the axial direction at an interval;

    a seal device (16) disposed between the first casing head and the shaft;

    a bearing device (13) disposed at the second side in the axial direction with respect to the seal device and disposed between the first casing head and the shaft;

    a shield part (11) fixed to a first side of the first casing head in the axial direction, and configured to define a suction flow passage (18) for introducing fluid into the impeller along with the diaphragm and to define an insulating space (10), which thermally insulates the first casing head from the suction flow passage, between the shield part and the first casing head, and
    characterized by comprising an insulator (49) filled in the insulating space.


     
    2. The centrifugal compressor according to Claim 1, wherein the shield part is fixed to only an end of the first casing head at the outer side in the radial direction, and is formed such that a clearance (C) is provided between an end of the shield part at an inner side in the radial direction and an outer circumferential surface of the shaft.
     
    3. The centrifugal compressor according to Claim 1 or 2, further comprising
    a temperature regulator (60) having:

    a pipe line (61) formed inside the first casing head;

    a temperature regulator main body (62) connected to the pipe line; and

    a heat medium introduced into the temperature regulator main body via the pipe line.


     
    4. The centrifugal compressor according to any one of Claims 1 to 3, further comprising:

    a second casing head (5) disposed at a first side of the diaphragm in the axial direction at an interval;

    a discharge side bearing device (14) disposed between the second casing head and the shaft; and

    a second shield part (64) fixed to a second side of the second casing head in the axial direction and configured to define a discharge flow passage (19) discharging the fluid from the impeller along with the diaphragm and to define a discharge side insulating space (65) between the second shield part and the second casing head.


     
    5. The centrifugal compressor according to Claim 1, wherein:

    the shield part has a shield member in which an end thereof at an outer side in the radial direction and an end thereof at an inner side in the radial direction are fixed to a first side of the first casing head in the axial direction; and

    the insulating space is sealed by the shield member.


     
    6. The centrifugal compressor according to Claim 5, further comprising a seal device provided for at least one of a plurality of fixing parts (40) of the shield member and the first casing head.
     


    Ansprüche

    1. Zentrifugalverdichter (1, 1B, 1C) umfassend:

    einen Rotor (7) mit einer Welle (8), die sich entlang einer Achse (A) erstreckt, und ein Laufrad (9), das an einer Außenfläche der Welle befestigt ist und ein Fluid (G), das in einer ersten Seite (Da1) in einer axialen Richtung (Da) strömt, zu einer Außenseite in einer radialen Richtung der unter Druck stehenden Achse befördert;

    eine Membran (3), die so ausgebildet ist, dass sie das Laufrad von einer äußeren Umfangsseite umgibt;

    einen ersten Gehäusekopf (4), der an einer zweiten Seite (Da2) der Membran in axialer Richtung in einem Abstand angeordnet ist;

    eine Dichtungsvorrichtung (16), die zwischen dem ersten Gehäusekopf und der Welle angeordnet ist;

    eine Lagervorrichtung (13), die an der zweiten Seite in axialer Richtung in Bezug auf die Dichtungsvorrichtung angeordnet ist und zwischen dem ersten Gehäusekopf und der Welle angeordnet ist;

    ein Abschirmteil (11), das an einer ersten Seite des ersten Gehäusekopfs in axialer Richtung befestigt ist und so ausgebildet ist, dass es zusammen mit der Membran einen Ansaugströmungskanal (18) definiert, um Fluid in das Laufrad einzubringen und dass es zwischen dem Abschirmteil und dem ersten Gehäusekopf einen Isolierraum (10) definiert, welcher den ersten Gehäusekopf von dem Ansaugströmungskanal thermisch isoliert, und gekennzeichnet dadurch, dass er ein Isoliermaterial (49) aufweist, das in den Isolierraum eingefüllt ist.


     
    2. Zentrifugalverdichter nach Anspruch 1, wobei das Abschirmteil an nur einem Ende des ersten Gehäusekopfs an der Außenseite in radialer Richtung befestigt ist und so ausgebildet ist, dass ein Abstand (C) zwischen einem Ende des Abschirmteils an einer Innenseite in radialer Richtung und einer äußeren Umfangsfläche der Welle vorgesehen ist.
     
    3. Zentrifugalverdichter nach Anspruch 1 oder 2, weiterhin umfassend einen Temperaturregler (60) mit:

    einer Rohrleitung (61), die in dem ersten Gehäusekopf gebildet ist;

    einem Temperaturregler-Hauptkörper (62), der mit der Rohrleitung verbunden ist; und

    ein Wärmemedium, das in den Temperaturregler-Hauptkörper über die Rohrleitung eingebracht wird.


     
    4. Zentrifugalverdichter nach einem der Ansprüche 1 bis 3, weiterhin umfassend:

    einen zweiten Gehäusekopf (5), der an einer ersten Seite der Membran in axialer Richtung in einem Abstand angeordnet ist;

    eine Auslassseite-Lagervorrichtung (14), die zwischen dem zweiten Gehäusekopf und der Welle angeordnet ist; und

    ein zweites Abschirmteil (64), das an einer zweiten Seite des zweiten Gehäusekopfs in der axialen Richtung befestigt ist und so ausgebildet ist, dass es zusammen mit der Membran einen Auslassströmungskanal (19) definiert, der das Fluid von dem Laufrad auslässt und dass es einen Isolierraum (65) auf der Auslassseite zwischen dem zweiten Abschirmteil und dem zweiten Gehäusekopf definiert.


     
    5. Zentrifugalverdichter nach Anspruch 1, wobei

    das Abschirmteil ein Abschirmelement hat, von welchem ein Ende an einer Außenseite in radialer Richtung und ein Ende desselben an einer Innenseite in radialer Richtung mit einer ersten Seite des ersten Gehäusekopfs in axialer Richtung befestigt sind; und

    der Isolierraum durch das Abschirmelement abgedichtet ist.


     
    6. Zentrifugalverdichter nach Anspruch 5, weiterhin umfassend eine Dichtungsvorrichtung, die für mindestens eines einer Vielzahl von Befestigungsteilen (40) des Abschirmelements und des ersten Gehäusekopfes vorgesehen ist.
     


    Revendications

    1. Compresseur centrifuge (1, 1B, 1C) comprenant :

    un rotor (7) ayant un arbre (8) qui s'étend le long d'un axe (A) et un rouet (9) qui est fixé sur une surface externe de l'arbre et fournit un fluide (G) qui s'écoule dans un premier côté (Da1) dans une direction axiale (Da) vers un côté externe dans une direction radiale de l'axe sous pression ;

    un diaphragme (3) configuré pour entourer la roue à partir d'un côté circonférentiel externe ;

    une première tête de carter (4) disposée au niveau d'un second côté (Da2) du diaphragme dans la direction axiale à un intervalle ;

    un dispositif de joint d'étanchéité (16) disposé entre la première tête de carter et l'arbre ;

    un dispositif de palier (13) disposé au niveau du second côté dans la direction axiale par rapport au dispositif de joint d'étanchéité et disposé entre la première tête de carter et l'arbre ;

    une partie de protection (11) fixée à un premier côté de la première tête de carter dans la direction axiale, et configurée pour définir un passage d'écoulement d'aspiration (18) pour introduire le fluide dans la roue conjointement avec le diaphragme et pour définir un espace d'isolation (10), qui isole thermiquement la première tête de carter du passage d'écoulement d'aspiration, entre la partie de protection et la première tête de carter, et

    caractérisé en ce qu'il comprend l'espace d'isolation remplit avec un isolant (49).


     
    2. Compresseur centrifuge selon la revendication 1, dans lequel la partie de protection est fixée uniquement sur une extrémité de la première tête de carter au niveau du côté externe dans la direction radiale, et est formée de sorte qu'un jeu (C) est prévu entre une extrémité de la partie de protection au niveau d'un côté interne dans la direction radiale et une surface circonférentielle externe de l'arbre.
     
    3. Compresseur centrifuge selon la revendication 1 ou 2, comprenant en outre :
    un régulateur de température (60) ayant :

    une conduite (61) formée à l'intérieur de la première tête de carter ;

    un corps principal de régulateur de température (62) raccordé à la conduite ; et

    un fluide caloporteur introduit dans le corps principal de régulateur de température via la conduite.


     
    4. Compresseur centrifuge selon l'une quelconque des revendications 1 à 3, comprenant en outre :

    une seconde tête de carter (5) disposée au niveau d'un premier côté du diaphragme dans la direction axiale à un intervalle ;

    un dispositif de palier du côté de la décharge (14) disposé entre la seconde tête de carter et l'arbre ; et

    une seconde partie de protection (64) fixée à un second côté de la seconde tête de carter dans la direction axiale et configurée pour définir un passage d'écoulement de décharge (19) déchargeant le fluide de la roue conjointement avec le diaphragme et pour définir un espace d'isolation du côté de la décharge (65) entre la seconde partie de protection et la seconde tête de carter.


     
    5. Compresseur centrifuge selon la revendication 1, dans lequel :

    la partie de protection a un élément de protection dans lequel son extrémité, au niveau d'un côté externe dans la direction radiale et son extrémité au niveau d'un côté interne dans la direction radiale sont fixées sur un premier côté de la première tête de carter dans la direction axiale ; et

    l'espace d'isolation est scellé par l'élément de protection.


     
    6. Compresseur centrifuge selon la revendication 5, comprenant en outre un dispositif de joint d'étanchéité prévu pour au moins l'une d'une pluralité de parties de fixation (40) de l'élément de protection et la première tête de carter.
     




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    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description