Rotating machine and method for repairing a rotating machine

Abstract

Provided is a supercharger (100) including: an impeller; a scroll case formed to surround an outer peripheral side of the impeller; a bearing case (20) disposed in abutment with the scroll case; and a linking portion (40) linking the scroll case and the bearing case (20), the linking portion (40) having fastening bolts (41) and fastening bolts (42), a plurality of through holes (21) being formed at intervals along a circumferential direction (CD) in the bearing case (20), the scroll case and the bearing case (20) being linked in a state in which the plurality of fastening bolts (41) and the plurality of fastening bolts (42) are inserted into the plurality of through holes (21), and the tensile strength of the fastening bolts (41) being higher than the tensile strength of the fastening bolts (42).

Description

Technical Field

[0001] This invention relates to rotating machinery and methods for repairing rotating machinery. Background Technology

[0002] Conventionally, in rotating machinery such as compressors and turbines, there is a requirement to improve safety so that in the event of damage to rotating bodies such as impellers housed inside, broken parts do not fly out of the device (for example, see Patent Document 1). Patent Document 1 discloses a method in which a first housing forming a vortex chamber and a second housing disposed opposite to the first housing are fastened together by fastening members on both the outer peripheral side and the inner peripheral side of the vortex chamber.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-16163

[0006] The technical problem that the invention aims to solve

[0007] In the rotating machinery disclosed in Patent Document 1, safety can be improved by increasing the tensile strength of the fastening components to prevent broken components from flying out of the device. However, it is known that in fastening components with high tensile strength (e.g., components called high-strength bolts or ultra-high-strength bolts), a phenomenon known as delayed failure occurs, where the steel suddenly breaks after a specified time following the application of static stress.

[0008] Therefore, although increasing the tensile strength of the fastening components can improve safety and prevent broken components from flying outwards, it is possible that the fastening force between the first and second housings may weaken or the connection between the first and second housings may detach during normal use of the rotating machinery due to delayed failure. Summary of the Invention

[0009] The present invention was made in view of the following circumstances, and its object is to provide rotating machinery and a method for repairing rotating machinery that can improve safety so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts do not fly out of the device, and suppress adverse conditions caused by delayed failure of fastening bolts.

[0010] Technical means for solving technical problems

[0011] One aspect of the present invention comprises a rotating machine comprising: an impeller connected to a rotating shaft rotating along an axis; a first housing disposed along the axis and forming an annular shape surrounding the outer periphery of the impeller; a second housing disposed adjacent to the first housing along the axis and forming an annular shape; and a connecting portion that connects the first housing and the second housing at a predetermined position on the axis at a plurality of circumferential locations around the axis, the connecting portion having a first fastening bolt and a second fastening bolt formed as shafts extending along the axis, a plurality of through holes extending along the axis being spaced apart circumferentially in at least one of the first housing and the second housing, the first housing and the second housing being connected with the plurality of first fastening bolts and the plurality of second fastening bolts inserted into the plurality of through holes, wherein the tensile strength of the first fastening bolt is higher than that of the second fastening bolt.

[0012] In one aspect of the present invention, a method for repairing rotating machinery includes: an impeller connected to a rotating shaft rotating along an axis; a first housing disposed along the axis and forming an annular shape surrounding the outer periphery of the impeller; and a second housing disposed adjacent to the first housing along the axis and forming an annular shape, wherein a plurality of through holes extending along the axis are spaced apart circumferentially in at least one of the first housing and the second housing. The method for repairing the rotating machinery includes: a disassembly step of disassembling at least one of a plurality of second fastening bolts, the plurality of second fastening bolts being inserted into the plurality of through holes and connecting the first housing and the second housing; and a connection step of inserting a first fastening bolt into the through hole where the second fastening bolt has been disassembled, thereby connecting the first housing and the second housing, wherein the tensile strength of the first fastening bolt is higher than that of the second fastening bolt.

[0013] The effects of the invention

[0014] According to the present invention, rotating machinery and a method for repairing rotating machinery can be provided, which can improve safety so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts do not fly out of the device, and suppress adverse conditions caused by delayed failure of fastening bolts. Attached Figure Description

[0015] Figure 1 This is a longitudinal sectional view showing the turbocharger according to the first embodiment of the present invention.

[0016] Figure 2 yes Figure 1 The image shows an end view of the supercharger from direction AA.

[0017] Figure 3 yes Figure 1 The image shows a BB-oriented end view of the supercharger.

[0018] Figure 4 This is a flowchart illustrating a method for repairing a turbocharger according to the first embodiment of the present invention.

[0019] Figure 5 This is a longitudinal sectional view showing the turbocharger according to the second embodiment of the present invention.

[0020] Figure 6 yes Figure 5 The supercharger shown is a CC-direction end view.

[0021] Figure 7 yes Figure 5 The image shows a DD-side end view of the supercharger. Detailed Implementation

[0022] [First Implementation Method]

[0023] Hereinafter, the booster (compressor; rotating machinery) 100 of the first embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a longitudinal sectional view showing the turbocharger 100 of this embodiment. Figure 2 yes Figure 1 The end view of the supercharger 100 shown is taken from direction AA. Figure 3 yes Figure 1 The end view of the supercharger 100 shown is taken from the BB direction.

[0024] The turbocharger 100 of this embodiment is a device that compresses the intake gas (e.g., air) and sends it into the internal combustion engine. Figure 1 As shown, the turbocharger 100 of this embodiment includes a turbine (not shown), a centrifugal compressor 10, a muffler 15 (sound absorption device), and a bearing housing (second housing) 20. The turbine and the centrifugal compressor 10 are respectively connected to a rotor shaft 30. The rotor shaft 30 is supported by the bearing housing 20 in a state that allows it to rotate about the axis X.

[0025] The turbine (not shown) has a turbine disk (not shown) on which turbine blades are mounted and connected to a rotor shaft 30. The turbine disk rotates about axis X by exhaust gas discharged from the internal combustion engine and directed to the turbine blades. The rotation of the turbine disk about axis X causes the rotor shaft 30, to which the turbine disk is connected, to rotate about axis X.

[0026] The centrifugal compressor 10 is a device that compresses air flowing in from outside the turbocharger 100 and supplies the compressed air (hereinafter referred to as compressed air) to a scavenging box (not shown) that communicates with the inside of the cylinder liner (not shown) constituting the internal combustion engine. The centrifugal compressor 10 includes an impeller 11, a guide tube 12, and a scroll housing (first housing) 13.

[0027] like Figure 1 As shown, the impeller 11 is connected to the rotor shaft 30 extending along the axis X, and rotates about the axis X as the rotor shaft 30 rotates about the axis X. The impeller 11 compresses the air flowing in from the intake 11a and discharges it from the outlet 11b by rotating about the axis X.

[0028] like Figure 1 As shown, the impeller 11 includes a hub 11c mounted on the rotor shaft 30 and blades 11d mounted on the outer circumferential surface of the hub 11c. The impeller 11 has a space formed by the outer circumferential surface of the hub 11c and the inner circumferential surface of the guide tube 12, which is divided into multiple spaces by the blades 11d. The impeller 11 performs work on the air flowing in from the inlet 11a along the X-axis, causing the air to be discharged radially orthogonal to the X-axis, and the compressed air discharged from the outlet 11b flows into the diffuser 13e.

[0029] The guide tube 12 is a cylindrical component that houses the impeller 11 around the axis X and discharges air flowing in from the intake port 12a along the axis X to the outlet port 11b. Together with the impeller 11, the guide tube 12 guides the air flowing in from the intake port 11a along the axis X in a radial direction orthogonal to the axis X and directs it to the outlet port 11b.

[0030] The vortex housing 13 is a device that allows compressed air discharged from the outlet 11b to flow in and converts the kinetic energy (dynamic pressure) of the compressed air into pressure energy (static pressure). The vortex housing 13 is disposed on the radial outer periphery orthogonal to the axis X relative to the guide tube 12. The vortex housing 13 is disposed along the axis X and forms an annular shape surrounding the outer periphery of the impeller 11.

[0031] like Figure 1 As shown, a diffuser 13e is installed in the vortex housing 13. The diffuser 13e is an airfoil component disposed downstream of the outlet 11b of the impeller 11, forming a flow path that guides compressed air from the outlet 11b to the vortex chamber 13d. The diffuser 13e is configured to surround the outlet 11b of the compressed air disposed around the entire circumference of the impeller 11.

[0032] The diffuser 13e converts the kinetic energy (dynamic pressure) of the compressed air into pressure energy (static pressure) by slowing down the flow velocity of the compressed air discharged from the outlet 11b of the impeller 11. The compressed air, whose flow velocity is slowed down as it passes through the diffuser 13e, flows into the vortex chamber 13d, which is connected to the diffuser 13e. The compressed air flowing into the vortex chamber 13d is discharged to the discharge pipe (not shown).

[0033] The bearing housing 20 is a ring-shaped component formed around the axis X, and is disposed adjacent to the scroll housing 13 along the axis X. The bearing housing 20 is connected to the scroll housing 13 via a connecting part 40.

[0034] like Figure 1 As shown, the connecting part 40 connects the vortex housing 13 and the bearing housing 20 at multiple locations along the circumferential direction CD around the axis X at position X1 on the axis X. Figure 2 As shown, the connecting portion 40 includes: a shaft-shaped fastening bolt (first fastening bolt) 41 extending along the axis X, and a shaft-shaped fastening bolt (second fastening bolt) 42 extending along the axis X. External threads are formed on the outer peripheral surfaces of the fastening bolts 41 and 42, respectively.

[0035] The lengths and outer diameters of fastening bolts 41 and 42 are equal. On the other hand, the tensile strength of fastening bolt 41 is higher than that of fastening bolt 42. The tensile strength of fastening bolt 41 is preferably a strength that ensures safety, so that in the event of damage to impeller 11 and subsequent breakage, the broken parts will not fly out of the booster 100.

[0036] The tensile strength of the fastening bolt 41 is preferably, for example, 1200 MPa (N / mm²). 2 Above 1200 MPa (N / mm²). 2 Fastening bolts with a tensile strength of 1080 MPa or higher can be used, for example, as 12G hot-dip galvanized high-strength bolts "12GSHTB (registered trademark)". Alternatively, bolts made of YAG300 (martensitic aging steel) can be used, for example. The yield strength of the fastening bolt 41 is more preferably 1080 MPa (N / mm²). 2 The tensile strength of the fastening bolt 42 is preferably a strength that does not easily lead to delayed failure, for example, preferably 1100 MPa (N / mm). 2 )the following.

[0037] The bearing housing 20 has a plurality of through holes 21 spaced apart along the circumferential direction CD and extending along the axis X. A fastening hole 13a extending along the axis X is formed on the end face of the vortex housing 13 opposite to the through holes 21. An internal thread is formed on the inner circumferential surface of the fastening hole 13a.

[0038] The scroll housing 13 and the bearing housing 20 are connected with multiple fastening bolts 41 and 42 inserted into multiple through holes 21. The scroll housing 13 and the bearing housing 20 are connected by engaging the external threads formed on the outer peripheral surfaces of the fastening bolts 41 and 42 with the internal threads formed on the inner peripheral surfaces of the fastening holes 13a.

[0039] like Figure 2 As shown, the plurality of through holes 21 are configured such that the distance from each of the plurality of through holes 21 to the axis X is constant, D1. Figure 2 The plurality of through holes 21 shown are arranged at 15-degree intervals at 24 locations along the circumferential direction CD about the axis X. Furthermore, the number of locations where the plurality of through holes 21 are arranged along the circumferential direction CD can be any number other than 24 locations.

[0040] like Figure 2 As shown, the fastening bolt 42 is inserted into four of the 24 through holes 21. The through holes 21 for inserting the fastening bolt 42 are arranged at 45-degree intervals in eight locations circumferentially. On the other hand, the fastening bolt 41, which has a higher tensile strength than the fastening bolt 42, is inserted into 20 of the 24 through holes 21. The fastening bolt 41 is inserted into the through holes 21 other than the four locations for inserting the fastening bolt 42.

[0041] exist Figure 2 In the example shown, fastening bolts 42 are inserted at 4 of the 24 through holes 21, and fastening bolts 41 are inserted at 20 of the 24 through holes 21, but other methods are also possible. For example, the number of locations for inserting fastening bolts 42 could be set to 8 or 12, and fastening bolts 41 could be inserted at other locations.

[0042] In this case, the through holes 21 into which the fastening bolts 42 are inserted are preferably positioned symmetrically with respect to the axis X. Furthermore, the through holes 21 into which the fastening bolts 42 are inserted are preferably positioned at equal intervals along the circumferential direction CD. Additionally, it is preferable that the number of fastening bolts 41 inserted into the plurality of through holes 21 is greater than the number of fastening bolts 42 inserted into the plurality of through holes 21.

[0043] The silencer 15 (sound-absorbing device) is a device that reduces the noise level by absorbing a portion of the noise generated by the centrifugal compressor 10. The silencer 15 is installed at the suction inlet 12a of the guide tube 12 of the centrifugal compressor 10. The silencer 15 causes noise to be absorbed along the... Figure 1 The arrow shown changes the direction of airflow from the radially outer side to the direction along the axis X and guides it to the intake port 12a of the guide tube 12.

[0044] The muffler 15 includes a muffler housing (second housing) 15a and a muffler housing 15b. The muffler housing 15a and the muffler housing 15b are arranged at a distance from each other along the axis X, forming a flow path for air circulation between the muffler housing 15a and the muffler housing 15b.

[0045] The muffler housing 15a is a ring-shaped component formed around the axis X, and is disposed adjacent to the vortex housing 13 along the axis X. The muffler housing 15a is connected to the vortex housing 13 via a connecting part 50.

[0046] like Figure 1 As shown, the connecting part 50 connects the vortex housing 13 and the muffler housing 15a at multiple locations along the circumferential direction CD around the axis X at position X2 on the axis X. Figure 3 As shown, the connecting portion 50 includes: a shaft-shaped fastening bolt (first fastening bolt) 51 extending along the axis X, and a shaft-shaped fastening bolt (second fastening bolt) 52 extending along the axis X. External threads are formed on the outer peripheral surfaces of the fastening bolts 51 and 52, respectively.

[0047] The lengths and outer diameters of fastening bolts 51 and 52 are equal. On the other hand, the tensile strength of fastening bolt 51 is higher than that of fastening bolt 52. The tensile strength of fastening bolt 51 is preferably a strength that ensures safety, so that in the event of damage to impeller 11 and subsequent breakage, the broken parts do not fly outwards from the booster 100.

[0048] The tensile strength of the fastening bolt 51 is preferably, for example, 1200 MPa (N / mm²). 2 Above 1200 MPa (N / mm²). 2 Fastening bolts with a tensile strength of 1080 MPa or higher can be used, for example, as 12G hot-dip galvanized high-strength bolts "12GSHTB (registered trademark)". Alternatively, bolts made of YAG300 (martensitic aging steel) can be used, for example. The yield strength of the fastening bolt 51 is more preferably 1080 MPa (N / mm²). 2 The tensile strength of the fastening bolt 52 is preferably a strength that does not easily lead to delayed failure, for example, preferably 1100 MPa (N / mm). 2 )the following.

[0049] The muffler housing 15a has a plurality of through holes 15c spaced apart along the circumferential direction CD and extending along the axis X. A fastening hole 13b extending along the axis X is formed on the end face of the vortex housing 13 opposite to the through holes 15c. An internal thread is formed on the inner circumferential surface of the fastening hole 13b.

[0050] The vortex housing 13 and the muffler housing 15a are connected with multiple fastening bolts 51 and 52 inserted into multiple through holes 15c. The vortex housing 13 and the muffler housing 15a are connected by engaging the external threads formed on the outer peripheral surfaces of the fastening bolts 51 and 52 with the internal threads formed on the inner peripheral surfaces of the fastening holes 13b.

[0051] like Figure 3 As shown, the plurality of through holes 15c are configured such that the distance from each of the plurality of through holes 15c to the axis X is a constant D2. Figure 3 The plurality of through holes 15c shown are arranged at 15-degree intervals at 24 locations along the circumferential direction CD about the axis X. Furthermore, the number of locations where the plurality of through holes 15c are arranged along the circumferential direction CD can be any number other than 24 locations.

[0052] like Figure 3 As shown, the fastening bolt 52 is inserted into four of the 24 through holes 15c. The through holes 15c for inserting the fastening bolt 52 are arranged at 45-degree intervals in eight locations circumferentially. On the other hand, the fastening bolt 51, which has a higher tensile strength than the fastening bolt 52, is inserted into 20 of the 24 through holes 15c. The fastening bolt 51 is inserted into the through holes 15c other than the four locations for inserting the fastening bolt 52.

[0053] exist Figure 3 In the example shown, fastening bolts 52 are inserted at 4 of the 24 through holes 15c, and fastening bolts 51 are inserted at 20 of the 24 through holes 15c, but other methods are also possible. For example, the number of locations for inserting fastening bolts 52 could be 8 or 12, or fastening bolts 51 could be inserted at other locations.

[0054] In this case, the through holes 15c into which the fastening bolts 52 are inserted are preferably positioned symmetrically with respect to the axis X. Furthermore, the through holes 15c into which the fastening bolts 52 are inserted are preferably positioned at equal intervals along the circumferential direction CD. Additionally, it is preferable that the number of fastening bolts 51 inserted into the plurality of through holes 15c is greater than the number of fastening bolts 52 inserted into the plurality of through holes 15c.

[0055] Next, the repair method of the turbocharger 100 of this embodiment will be described with reference to the accompanying drawings. Figure 4 This is a flowchart illustrating the repair method of the turbocharger 100 according to this embodiment.

[0056] The repair method of this embodiment is a method for repairing a turbocharger 100 in which the scroll housing 13 and the bearing housing 20 are fastened only by fastening bolts 42, and the scroll housing 13 and the muffler housing 15a are fastened only by fastening bolts 52.

[0057] In execution Figure 4 In the supercharger 100 prior to the repair method shown, the scroll housing 13 and bearing housing 20 are fastened only by fastening bolts 42, and the scroll housing 13 and muffler housing 15a are fastened only by fastening bolts 52.

[0058] exist Figure 4 In step S101 (first disassembly step), the operator removes at least one of the fastening bolts 42 inserted into the through hole 21. The fastening bolt 42 is a bolt inserted into the through hole 21 that connects the volute housing 13 and the bearing housing 20. For example, the operator will remove the bolt inserted into... Figure 2 Remove the 20 fastening bolts 42 at the position of the fastening bolt 41 shown.

[0059] In step S102 (first connection process), the operator inserts a fastening bolt 41 into the through hole 21 where the fastening bolt 42 has been removed, and fastens it into the fastening hole 13a of the vortex housing 13 to connect the vortex housing 13 and the bearing housing 20.

[0060] In step S103 (second disassembly step), the operator removes at least one of the fastening bolts 52 inserted into the through hole 15c. The fastening bolt 52 is a bolt inserted into the through hole 15c and connecting the vortex housing 13 and the muffler housing 15a. For example, the operator will remove the bolt inserted into... Figure 3 Remove the 20 fastening bolts 52 at the location of the fastening bolt 51 shown.

[0061] In step S104 (second connection process), the operator inserts a fastening bolt 51 into the through hole 15c where the fastening bolt 52 has been removed, and fastens it into the fastening hole 13b of the vortex housing 13 to connect the vortex housing 13 and the muffler housing 15a.

[0062] Through the above procedures, the following turbocharger 100 is repaired, in which the scroll housing 13 and bearing housing 20 are fastened only by fastening bolts 42, and the scroll housing 13 and muffler housing 15a are fastened only by fastening bolts 52. In the repaired turbocharger 100, the scroll housing 13 and bearing housing 20 are fastened by both multiple fastening bolts 41 and multiple fastening bolts 42. Furthermore, in the repaired turbocharger 100, the scroll housing 13 and muffler housing 15a are fastened by both multiple fastening bolts 51 and multiple fastening bolts 52.

[0063] In the above description, fastening bolts 41 and 42 are fastened to fastening holes 13a formed in the scroll housing 13, but other methods are also possible. For example, through holes for fastening bolts 41 and 42 to be inserted may be provided in the scroll housing 13. In this case, the scroll housing 13 and the bearing housing 20 are connected by fastening nuts to fastening bolts 41 and 42 that pass through the through holes.

[0064] Furthermore, in the above description, fastening bolts 51 and 52 are fastened to the fastening holes 13b formed in the scroll housing 13, but other methods are also possible. For example, through holes for inserting fastening bolts 51 and 52 may be provided in the scroll housing 13. In this case, the scroll housing 13 and the muffler housing 15a are connected by fastening nuts to the fastening bolts 51 and 52 that pass through the through holes.

[0065] The booster 100 of this embodiment described above achieves the following functions and effects.

[0066] According to the turbocharger 100 of this embodiment, the connecting portion 40, which connects the annular vortex housing 13 surrounding the outer periphery of the impeller 11 and the bearing housing 20 disposed adjacent to the vortex housing 13, has shaft-shaped fastening bolts 51 and 52 extending along the axis X. The vortex housing 13 and the bearing housing 20 are connected with a plurality of fastening bolts 41 and 42 inserted into a plurality of through holes 21.

[0067] According to the turbocharger 100 of the present invention, since the tensile strength of the fastening bolt 41 is higher than that of the fastening bolt 42, the connection strength of the vortex housing 13 and the bearing housing 20 can be improved compared with the case where only the fastening bolt 52 is used to connect the vortex housing 13 and the bearing housing 20. This improves safety so that in the event of damage to the impeller 11 housed inside and subsequent breakage, the broken parts will not fly out of the device.

[0068] Furthermore, according to the turbocharger 100 of this embodiment, the tensile strength of the fastening bolt 42 is lower than that of the fastening bolt 41. Therefore, compared to the case where only the fastening bolt 41 is used to connect the scroll housing 13 and the bearing housing 20, adverse conditions caused by delayed failure of the fastening bolt 41 can be suppressed. That is, even if the fastening bolt 41 breaks due to delayed failure, the connection between the scroll housing 13 and the bearing housing 20 can be maintained by the fastening bolt 42.

[0069] Furthermore, according to the booster 100 of this embodiment, by having a greater number of fastening bolts 41 with higher tensile strength than fastening bolts 42 than the number of fastening bolts 42, safety can be sufficiently improved so that in the event of damage to the impeller 11 housed inside and subsequent breakage, the broken parts will not fly out of the device.

[0070] Furthermore, according to the turbocharger 100 of this embodiment, since the plurality of through holes 21 are configured to have a constant distance up to the axis X, the connection strength between the vortex housing 13 and the bearing housing 20 at each position in the circumferential direction CD around the axis X can be made uniform.

[0071] Furthermore, according to the booster 100 of this embodiment, since the length and outer diameter of the fastening bolts 41 and 42 are equal, the length and inner diameter of the plurality of through holes 21 can be made equal. Therefore, the time required to form the plurality of through holes 21 can be reduced.

[0072] The repair method for the turbocharger 100 described above achieves the following functions and effects.

[0073] According to the repair method of the turbocharger 100 of this embodiment, in the first disassembly step, at least one of the plurality of fastening bolts 42 that connect the annular vortex housing 13 surrounding the outer periphery of the impeller 11 and the bearing housing 20 disposed adjacent to the vortex housing 13 are removed. Then, in the first connection step, fastening bolts 41 are inserted into the through holes 21 where the fastening bolts 42 have been removed to connect the vortex housing 13 and the bearing housing 20.

[0074] According to the repair method of the turbocharger 100 in this embodiment, since the tensile strength of the fastening bolt 41 is higher than that of the fastening bolt 42, the connection strength of the vortex housing 13 and the bearing housing 20 can be improved compared with the case where only the fastening bolt 42 is used to connect the vortex housing 13 and the bearing housing 20. This improves safety so that in the event of damage to the impeller 11 housed inside and subsequent breakage, the broken parts will not fly out of the device.

[0075] Furthermore, according to the repair method of the turbocharger 100 in this embodiment, the tensile strength of the fastening bolt 42 is lower than that of the fastening bolt 41. Therefore, compared with the case where only the fastening bolt 41 is used to connect the scroll housing 13 and the bearing housing 20, adverse conditions caused by delayed failure of the fastening bolt can be suppressed. That is, even if the fastening bolt 41 breaks due to delayed failure, the connection between the scroll housing 13 and the bearing housing 20 can be maintained by the fastening bolt 42.

[0076] [Second Implementation]

[0077] Next, the booster 200 of the second embodiment of the present invention will be described with reference to the accompanying drawings. Figure 5 This is a longitudinal sectional view showing the turbocharger 200 of this embodiment. Figure 6 yes Figure 5 The supercharger 200 shown is viewed from the CC direction as an end view. Figure 7 yes Figure 5 The end view of the turbocharger 200 shown is taken from the DD direction.

[0078] The turbocharger 200 of this embodiment is a device that compresses the intake gas (e.g., air) and sends it into the internal combustion engine. Figure 5 As shown, the turbocharger 200 of this embodiment includes a turbine 210, a compressor (not shown), and a bearing housing (second housing) 220. The turbine 210 and the compressor are respectively connected to a rotor shaft 230. The rotor shaft 230 is supported by the bearing housing 20 in a state that allows it to rotate about the axis X.

[0079] The turbine 210 includes: an impeller 211 on which turbine blades are mounted, a turbine housing (first housing) 212 that houses the impeller 211, and an outlet housing (second housing) 213.

[0080] The impeller 211 is given a driving force to rotate about the axis X by the gas flowing in from the vortex chamber 212a of the turbine housing 212 (e.g., exhaust gas from an internal combustion engine). The rotor shaft 230 is rotated about the axis X by the driving force given to the impeller 211, thereby rotating the compressor connected via the rotor shaft 230.

[0081] The turbine housing 212 internally houses the impeller 211 and has a vortex chamber 212a for gas to flow into from the internal combustion engine. The turbine housing 212 is arranged along the axis X and forms an annular shape surrounding the outer periphery of the impeller 211.

[0082] The outlet casing 213 forms a flow path for the gas flowing from the vortex chamber 212a into the impeller 211 to exit. The outlet casing 213 is a ring-shaped component formed around the axis X and is disposed adjacent to the turbine casing 212 along the axis X. The outlet casing 213 is connected to the turbine casing 212 via a connecting part 240.

[0083] like Figure 5 As shown, the connecting part 240 connects the turbine housing 212 and the outlet housing 213 at multiple locations along the circumferential direction CD around the axis X at position X3 on the axis X. Figure 6 As shown, the connecting portion 240 includes: a shaft-shaped fastening bolt (first fastening bolt) 241 extending along the axis X, and a shaft-shaped fastening bolt (second fastening bolt) 242 extending along the axis X. External threads are formed on the outer peripheral surfaces of the fastening bolts 241 and 242, respectively.

[0084] Fastening bolts 241 and 242 have the same length and outer diameter. On the other hand, the tensile strength of fastening bolt 241 is higher than that of fastening bolt 242. The tensile strength of fastening bolt 241 is preferably a strength that can ensure safety, so that in the event of damage to impeller 211 and subsequent breakage, the broken parts will not fly out of the booster 200.

[0085] The tensile strength of the fastening bolt 241 is preferably, for example, 1200 MPa (N / mm²). 2 Above 1200 MPa (N / mm²). 2 Fastening bolts with a tensile strength of 1080 MPa or higher can be used, for example, as 12G hot-dip galvanized high-strength bolts "12GSHTB (registered trademark)". Alternatively, bolts made of YAG300 (martensitic aging steel) can be used, for example. The yield strength of the fastening bolt 241 is more preferably 1080 MPa (N / mm²). 2 The tensile strength of the fastening bolt 242 is preferably a strength that does not easily lead to delayed failure, for example, preferably 1100 MPa (N / mm). 2 )the following.

[0086] A plurality of through holes 213a extending along the axis X are formed at intervals along the circumferential direction CD in the outlet housing 213. A fastening hole 212b extending along the axis X is formed on the end face of the turbine housing 212 opposite to the through holes 213a. An internal thread is formed on the inner circumferential surface of the fastening hole 212b.

[0087] The turbine housing 212 and the outlet housing 213 are connected with multiple fastening bolts 241 and 242 inserted into multiple through holes 213a. The turbine housing 212 and the outlet housing 213 are connected by engaging the external threads formed on the outer peripheral surfaces of the fastening bolts 241 and 242 with the internal threads formed on the inner peripheral surfaces of the fastening holes 212b.

[0088] like Figure 6 As shown, the plurality of through holes 213a are configured such that the distance from each of the plurality of through holes 213a to the axis X is constant, D3. Figure 6 The plurality of through holes 213a shown are arranged at 30-degree intervals at 12 locations along the circumferential direction CD about the axis X. Furthermore, the number of locations where the plurality of through holes 213a are arranged along the circumferential direction CD can be any number other than 12 locations.

[0089] like Figure 6As shown, the fastening bolt 242 is inserted into four of the twelve through holes 213a. The through holes 213a for inserting the fastening bolt 242 are arranged at 90-degree intervals in the four locations circumferentially. On the other hand, the fastening bolt 241, which has a higher tensile strength than the fastening bolt 242, is inserted into eight of the twelve through holes 213a. The fastening bolt 241 is inserted into the through holes 213a other than the four locations for inserting the fastening bolt 242.

[0090] exist Figure 6 In the example shown, fastening bolts 242 are inserted at four of the twelve through holes 21, and fastening bolts 241 are inserted at eight of the twelve through holes 21, but other methods are also possible. For example, the locations for inserting fastening bolts 242 could be two or three, and fastening bolts 241 could be inserted at the other locations.

[0091] In this case, the through holes 213a into which the fastening bolts 242 are inserted are preferably positioned symmetrically with respect to the axis X. Furthermore, the through holes 213a into which the fastening bolts 242 are inserted are preferably positioned at equal intervals along the circumferential direction CD. Additionally, it is preferable that the number of fastening bolts 241 inserted into the plurality of through holes 213a is greater than the number of fastening bolts 242 inserted into the plurality of through holes 213a.

[0092] The bearing housing 220 is a ring-shaped component formed around the axis X, and is disposed adjacent to the turbine housing 212 along the axis X. The bearing housing 220 is connected to the turbine housing 212 via a connecting portion 250.

[0093] like Figure 5 As shown, the connecting part 250 connects the turbine housing 212 and the bearing housing 220 at multiple locations along the circumferential direction CD around the axis X at position X4 on the axis X. Figure 7 As shown, the connecting portion 250 includes: a shaft-shaped fastening bolt (first fastening bolt) 251 extending along the axis X, and a shaft-shaped fastening bolt (second fastening bolt) 252 extending along the axis X. External threads are formed on the outer peripheral surfaces of the fastening bolts 251 and 252, respectively.

[0094] Fastening bolts 251 and 252 have the same length and outer diameter. On the other hand, the tensile strength of fastening bolt 251 is higher than that of fastening bolt 252. The tensile strength of fastening bolt 251 is preferably a strength that ensures safety so that in the event of damage to impeller 211 and subsequent breakage, the broken parts do not fly outwards from the booster 200.

[0095] The tensile strength of the fastening bolt 251 is preferably, for example, 1200 MPa (N / mm²).2 Above 1200 MPa (N / mm²). 2 Fastening bolts with a tensile strength of 1080 MPa or higher can be used, for example, as 12G hot-dip galvanized high-strength bolts "12GSHTB (registered trademark)". Alternatively, bolts made of YAG300 (martensitic aging steel) can be used. The yield strength of the fastening bolt 251 is more preferably 1080 MPa (N / mm²). 2 The tensile strength of the fastening bolt 252 is preferably a strength that does not easily lead to delayed failure, for example, preferably 1100 MPa (N / mm). 2 )the following.

[0096] A plurality of through holes 221 extending along the axis X are formed at intervals along the circumferential direction CD in the bearing housing 220. A fastening hole 212c extending along the axis X is formed on the end face of the turbine housing 212 opposite to the through holes 221. An internal thread is formed on the inner circumferential surface of the fastening hole 212c.

[0097] The turbine housing 212 and the bearing housing 220 are connected with multiple fastening bolts 251 and 252 inserted into multiple through holes 221. The turbine housing 212 and the bearing housing 220 are connected by engaging the external threads formed on the outer peripheral surfaces of the fastening bolts 251 and 252 with the internal threads formed on the inner peripheral surfaces of the fastening holes 212c.

[0098] like Figure 7 As shown, the plurality of through holes 221 are configured such that the distance from each of the plurality of through holes 221 to the axis X is a constant D4. Figure 7 The plurality of through holes 221 shown are arranged at 30-degree intervals at 12 locations along the circumferential direction CD about the axis X. Furthermore, the number of locations where the plurality of through holes 221 are arranged along the circumferential direction CD can be any number other than 12 locations.

[0099] like Figure 7 As shown, the fastening bolt 252 is inserted into four of the twelve through holes 221. The through holes 221 for inserting the fastening bolt 252 are arranged at 90-degree intervals in the four locations circumferentially. On the other hand, the fastening bolt 251, which has a higher tensile strength than the fastening bolt 252, is inserted into eight of the twelve through holes 221. The fastening bolt 251 is inserted into the other through holes 221 besides the four locations for inserting the fastening bolt 252.

[0100] exist Figure 7In the example shown, fastening bolts 252 are inserted at 4 out of 12 through holes 221, or at 8 out of 12 through holes 221, but other methods are also possible. For example, the number of locations for inserting the fastening bolts 252 could be 4, 3, or even other locations.

[0101] In this case, the through holes 221 into which the fastening bolts 252 are inserted are preferably positioned symmetrically with respect to the axis X. Furthermore, the through holes 221 into which the fastening bolts 252 are inserted are preferably positioned at equal intervals along the circumferential direction CD. Additionally, it is preferable that the number of fastening bolts 251 inserted into the plurality of through holes 221 is greater than the number of fastening bolts 252 inserted into the plurality of through holes 221.

[0102] According to this embodiment, the turbocharger 200 includes a turbine housing 212, which has a vortex chamber 212a through which the gas from the guide impeller 211 flows out. In this turbocharger 200, safety can be improved so that in the event of damage to the impeller 211 housed inside and subsequent breakage, the broken parts will not fly out of the device, and adverse conditions caused by delayed failure of the fastening bolts can be suppressed.

[0103] The rotating machinery described in the above-described embodiment is, for example, as follows.

[0104] The rotating machinery (100, 200) of the present invention comprises: an impeller (11) connected to a rotating shaft (30) that rotates along an axis (X); a first housing (13) disposed along the axis and formed in an annular shape surrounding the outer periphery of the impeller; a second housing (15a, 20) disposed adjacent to the first housing along the axis and formed in an annular shape; and a connecting portion (40, 50) that connects the first housing and the second housing at predetermined positions (X1, X2) on the axis at multiple locations in the circumferential direction (CD) around the axis. The connecting portion has a first fastening bolt (41, 51) and a second fastening bolt (42, 52) formed as shafts extending along the axis. A plurality of through holes (15c, 21) extending along the axis are spaced apart circumferentially in at least one of the first housing and the second housing. The first housing and the second housing are connected by inserting the plurality of first fastening bolts and the plurality of second fastening bolts into the plurality of through holes. The tensile strength of the first fastening bolt is higher than that of the second fastening bolt. For example, the tensile strength of the first fastening bolt is 1200 MPa or more, and the tensile strength of the second fastening bolt is 1100 MPa or less.

[0105] According to the rotating machinery of the present invention, a connecting portion for connecting a first housing formed in an annular shape surrounding the outer periphery of an impeller and a second housing disposed adjacent to the first housing has a first fastening bolt and a second fastening bolt formed in a shaft shape extending along an axis. The first housing and the second housing are connected with a plurality of first fastening bolts and a plurality of second fastening bolts inserted into a plurality of through holes.

[0106] According to the rotating machinery of the present invention, since the tensile strength of the first fastening bolt is higher than that of the second fastening bolt, the connection strength of the first housing and the second housing can be improved compared with the case where only the second fastening bolt is used to connect the first housing and the second housing. This improves safety so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts do not fly out of the device.

[0107] Furthermore, in the rotating machinery according to the present invention, the tensile strength of the second fastening bolt is lower than that of the first fastening bolt. Therefore, compared to the case where only the first fastening bolt is used to connect the first housing and the second housing, adverse conditions caused by delayed failure of the fastening bolt can be suppressed. That is, even if the first fastening bolt breaks due to delayed failure, the connection between the first housing and the second housing can be maintained by the second fastening bolt.

[0108] In the rotating machinery of the present invention, the following structure may also be adopted, wherein the number of first fastening bolts inserted into the plurality of through holes is greater than the number of second fastening bolts inserted into the plurality of through holes.

[0109] According to this rotating machinery structure, since the number of first fastening bolts with higher tensile strength than the second fastening bolts is greater than the number of second fastening bolts, safety can be significantly improved so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts will not fly out of the device.

[0110] In the rotating machinery of the present invention, a structure may also be adopted in which the plurality of through holes are configured such that the distance from each of the plurality of through holes to the axis is constant.

[0111] According to the rotating machinery of this structure, since multiple through holes are configured to maintain a constant distance up to the axis, the connection strength between the first and second housings at various positions around the axis can be made uniform.

[0112] In the rotating machinery of the present invention, the following structure may also be adopted, wherein the length and outer diameter of the first fastening bolt and the second fastening bolt are equal.

[0113] In the rotating machinery according to this structure, since the length and outer diameter of the first and second fastening bolts are equal, the length and inner diameter of multiple through holes can be made equal. Therefore, the time required to form multiple through holes can be reduced.

[0114] In the rotating machinery of the present invention, the following structure may also be adopted, wherein the first housing is a component forming a vortex chamber (13d) into which the fluid compressed by the impeller flows in.

[0115] According to the rotating machinery of this structure, the rotating machinery has a first housing having a vortex chamber for the inflow of fluid compressed by the impeller. In this rotating machinery, safety can be improved so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts will not fly out of the device, and adverse conditions caused by delayed failure of fastening bolts can be suppressed.

[0116] In the rotating machinery of the present invention, the following structure may also be adopted, wherein the first housing is a component that forms a vortex chamber (212a) through which fluid guiding the impeller flows out.

[0117] According to the rotating machinery of this structure, the rotating machinery has a first housing with a vortex chamber through which fluid flows out of the guide impeller. In this rotating machinery, safety can be improved so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts will not fly out of the device, and adverse conditions caused by delayed failure due to fastening bolts can be suppressed.

[0118] The repair method for rotating machinery described in this embodiment above can be mastered as follows.

[0119] In the repair method of the rotating machinery of the present invention, the rotating machinery includes: an impeller connected to a rotating shaft rotating along an axis; a first housing disposed along the axis and forming an annular shape surrounding the outer periphery of the impeller; and a second housing disposed adjacent to the first housing along the axis and forming an annular shape, wherein a plurality of through holes extending along the axis are spaced apart circumferentially in at least one of the first housing and the second housing, and the repair method of the rotating machinery includes: a disassembly step (S101, S103) of disassembling at least one of a plurality of second fastening bolts, wherein the plurality of second fastening bolts are inserted into the plurality of through holes and the first housing and the second housing are connected; and a connection step (S102, S104) of inserting a first fastening bolt into the through hole where the second fastening bolt has been disassembled and connecting the first housing and the second housing, wherein the tensile strength of the first fastening bolt is higher than the tensile strength of the second fastening bolt.

[0120] According to the repair method for rotating machinery of the present invention, in the disassembly step, at least one of a plurality of second fastening bolts is removed, which connect a first housing formed in an annular shape surrounding the outer periphery of the impeller and a second housing disposed adjacent to the first housing. Then, in the connection step, a first fastening bolt is inserted into the through hole where the second fastening bolts have been removed to connect the first housing and the second housing.

[0121] According to the repair method of rotating machinery of the present invention, since the tensile strength of the first fastening bolt is higher than that of the second fastening bolt, the connection strength of the first housing and the second housing can be improved compared with the case where only the second fastening bolt is used to connect the first housing and the second housing. This improves safety so that in the event of damage to the impeller housed inside and subsequent breakage, the broken parts do not fly out of the device.

[0122] Furthermore, in the repair method for rotating machinery according to the present invention, the tensile strength of the second fastening bolt is lower than that of the first fastening bolt. Therefore, compared to the case where only the first fastening bolt is used to connect the first housing and the second housing, adverse conditions caused by delayed failure of the fastening bolt can be suppressed. That is, even if the first fastening bolt breaks due to delayed failure, the connection between the first housing and the second housing can be maintained by the second fastening bolt.

[0123] Symbol Explanation

[0124] 10 Centrifugal Compressor

[0125] 11 Impeller

[0126] 13. Scroll-shaped shell (first shell)

[0127] 13a, 13b Fastening Holes

[0128] 13d vortex chamber

[0129] 15a and 15b muffler housings

[0130] 15c through hole

[0131] 20. Bearing housing (second housing)

[0132] 21 through holes

[0133] 30 rotor shaft

[0134] 40, 50 connecting parts

[0135] 41, 42, 51, 52 Fastening Bolts

[0136] 100, 200 turbochargers

[0137] 210 turbo

[0138] 211 Impeller

[0139] 212 Turbine housing (first housing)

[0140] 212a Vortex Chamber

[0141] 212b, 212c fastening holes

[0142] 213 Outlet Casing (Second Casing)

[0143] 213a Through Hole

[0144] 220 Bearing Housing (Second Housing)

[0145] 221 Through Hole

[0146] 230 rotor shaft

[0147] 240, 250 connecting parts

[0148] 241, 242, 251, 252 Fastening Bolts

[0149] CD Zhou Xiang

[0150] X-axis

Claims

1. A rotating machine, characterized in that, have: An impeller connected to a rotating shaft that rotates along an axis; A first housing is disposed along the axis and forms an annular shape around the outer periphery of the impeller; A second housing is disposed adjacent to the first housing along the axis and is formed in a ring shape; as well as A connecting portion, located at a predetermined position on the axis, connects the first housing and the second housing at multiple circumferential locations around the axis. The connecting portion has a first fastening bolt formed in the shape of a shaft extending along the axis and a second fastening bolt formed in the shape of a shaft extending along the axis. A plurality of through holes extending along the axis are formed at intervals along the circumferential direction in at least one of the first housing and the second housing. The first housing and the second housing are connected with the plurality of first fastening bolts and the plurality of second fastening bolts inserted into the plurality of through holes. The tensile strength of the first fastening bolt is higher than that of the second fastening bolt. The first fastening bolt and the second fastening bolt have the same length and outer diameter.

2. The rotating machinery according to claim 1, characterized in that, The tensile strength of the first fastening bolt is above 1200 MPa. The tensile strength of the second fastening bolt is below 1100 MPa.

3. The rotating machinery according to claim 1 or 2, characterized in that, The number of first fastening bolts inserted into the plurality of through holes is greater than the number of second fastening bolts inserted into the plurality of through holes.

4. The rotating machinery according to claim 1 or 2, characterized in that, The plurality of through holes are configured such that the distance from each of the plurality of through holes to the axis is constant.

5. The rotating machinery according to claim 1 or 2, characterized in that, The first housing is a component that forms a vortex chamber into which fluid compressed by the impeller flows.

6. The rotating machinery according to claim 1 or 2, characterized in that, The first housing is a component that forms a vortex chamber through which fluid directed to the impeller flows out.

7. A method for repairing rotating machinery, characterized in that, The rotating machinery includes: An impeller connected to a rotating shaft that rotates along an axis; A first housing is disposed along the axis and forms an annular shape around the outer periphery of the impeller; as well as A second housing, which is disposed adjacent to the first housing along the axis and is formed in a ring shape, A plurality of through holes extending along the axis are formed at intervals around the axis in at least one of the first housing and the second housing. The repair methods for this rotating machinery include: The disassembly process involves removing at least one of a plurality of second fastening bolts, which are inserted into a plurality of through holes and connect the first housing and the second housing; and In the connection process, a first fastening bolt is inserted into the through hole after the second fastening bolt has been removed, thereby connecting the first housing and the second housing. The tensile strength of the first fastening bolt is higher than that of the second fastening bolt. The first fastening bolt and the second fastening bolt have the same length and outer diameter.

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