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EP-3770441-B1 - COMPRESSOR AND METHOD FOR MANUFACTURING COMPRESSOR

EP3770441B1EP 3770441 B1EP3770441 B1EP 3770441B1EP-3770441-B1

Inventors

  • ODA, TAKASHI
  • SHINOHARA, HITOSHI

Dates

Publication Date
20260506
Application Date
20180427

Claims (18)

  1. A compressor (1) comprising: a casing (2, 2A, 2B, 2C, 2D, 2E, 2F) including an upper half casing (21, 21A, 21B, 21F ) having an upper half casing-divided surface as a horizontal surface (211) facing downward in a vertical direction and a lower half casing (22, 22A, 22F) having a lower half casing-divided surface (221) capable of abutting against the upper half casing-divided surface (211), the casing (2, 2A, 2B, 2C, 2D, 2E, 2F) having a tubular shape with both ends open; a bundle (10) including a plurality of impellers (112) rotatable about an axis (O), a plurality of diaphragms (13) in which in each of them, an impeller (112) is accommodated and a flow path introducing a fluid to a flow path of the impeller is formed, and two annular heads (14) respectively fixed on both sides in an axial direction in which the axis extends with respect to the plurality of diaphragms (13) and closing openings of the casing, the bundle (10) being accommodated in the casing (2, 2A, 2B, 2C, 2D, 2E, 2F); a communication clearance seal portion (16) sealing a communication clearance extending in the axial direction between outer peripheral surfaces of the plurality of diaphragms (13) and an inner peripheral surface of the casing (2, 2A, 2B, 2C, 2D, 2E, 2F) such that a suction port (23) through which the fluid flows in and a discharge port (24) through which the fluid is discharged communicate with each other, wherein the communication clearance seal portion (16) is an O ring; two restricting portions (18, 18A, 18B, 18D, 18F) each provided in at least one of the casing and one of the annular heads (14) and restricting a position of the annular heads (14) in the axial direction with respect to the casing (2, 2A, 2B, 2C, 2D, 2E, 2F); and a clearance seal attachment groove (261) to which the communication clearance seal portion (16) is attached is formed in the outer peripheral surface of one of the plurality of diaphragms (13); characterized in that the clearance seal attachment groove (261) is formed to become deeper toward a circumferential direction (Dc) from at least one of an upper vertex of the diaphragm (13) in the vertical direction (Dv) and a lower vertex of the diaphragm in the vertical direction.
  2. The compressor according to Claim 1, wherein at least one of the restricting portions (18, 18A, 18B, 18D, 18F) includes: a fitting recessed portion (181) formed in one of an outer peripheral surface of the one of the heads (14) and the inner peripheral surface of the casing (2, 2A, 2B, 2C, 2D, 2E, 2F); and a fitting projecting portion (182) formed in the other one of the outer peripheral surface of the one of the heads (14) and the inner peripheral surface of the casing and fitting into the fitting recessed portion (181).
  3. The compressor according to Claim 1, wherein at least one of the restricting portions (18, 18A, 18B, 18D, 18F) is disposed on an outside in the axial direction as a side opposite to a side where the plurality of diaphragms (13) is disposed with respect to the one of the heads in the casing (18, 18A, 18B, 18D, 18F) and is in contact with a surface of the one of the heads (14) facing the outside in the axial direction (O).
  4. The compressor according to Claim 3, wherein the casing (18, 18A, 18B, 18D, 18F) includes: a casing main body (31, 35) covering an outer peripheral surface of the bundle; and a protruding portion (32, 36) protruding from the casing main body (31, 35) toward an inside in a radial direction and in contact with an end surface of the one of the heads facing the outside in the axial direction, as the at least one of the restricting portions.
  5. The compressor according to Claim 3 or 4, wherein the at least one of the restricting portions (18, 18A, 18B, 18D, 18F) includes: an accommodating recessed portion (410) recessed from the inner peripheral surface of the casing to be positioned on the outside in the axial direction at least in part with respect to the one of the heads (14); a first restricting member (430) accommodated in the accommodating recessed portion (410) and in contact with the surface of the one of the heads (14) facing the outside in the axial direction; and a second restricting member (440) accommodated in the accommodating recessed portion (410) outside the first restricting member (430) in the axial direction and in contact with a surface of the accommodating recessed portion (410) facing an inside in the axial direction as a side where the plurality of diaphragms (13) is disposed and a surface of the first restricting member (430) facing the outside in the axial direction.
  6. The compressor according to any one of Claims 1 to 5, wherein the clearance seal attachment groove (261) is formed to be deepest at both end positions in a horizontal direction having an angular difference of 90 degrees in the circumferential direction of the diaphragm with respect to the upper vertex of the diaphragm in the vertical direction and the lower vertex of the diaphragm in the vertical direction.
  7. The compressor according to any one of Claims 1 to 6, further comprising a fastening portion (17) fixing one of the plurality of diaphragms (13) and a discharge side head as one of the heads (14) disposed at a position close to the discharge port (35), wherein the fastening portion (17) includes: a fixed hole (171) formed in a surface of one of the discharge side head (14) and the diaphragm(13) facing the axial direction and having a female screw in the fixed hole; a fastening through-hole (173) formed at a position overlapping the fixed hole (171) when seen from the axial direction in the other one of the discharge side head and the diaphragm; a bolt member (174) having a shaft portion (274) having an outer peripheral surface provided with a male screw and fixed to the fixed hole (171) in a state where the shaft portion (274) is inserted in the fastening through-hole (173) and a head portion formed in an end portion of the shaft portion; and an elastic member (175) disposed between the head portion of the bolt member (174) and a surface where the fastening through-hole is formed.
  8. The compressor according to any one of Claims 1 to 7, further comprising at least one head seal portion (15) providing sealing between one of the heads (14) and the casing, wherein the head seal portion includes: an annular ring insertion portion (620) movable in the axial direction from an outside of the the head or the casing and inserted between the outer peripheral surface of the the head (14) and the inner peripheral surface of the casing; an inside ring seal portion (670) providing sealing between an inner peripheral surface of the ring insertion portion and the outer peripheral surface of the the head (14); and an outside ring seal portion (630) providing sealing between an outer peripheral surface of the ring insertion portion and the inner peripheral surface of the casing.
  9. The compressor according to Claim 8, wherein the ring insertion portion (620) is detachable with respect to the head or the casing from the outside in the axial direction as the side opposite to the side where the plurality of diaphragms is disposed.
  10. The compressor according to Claim 8 or 9, wherein an insertion clearance diameter-enlarged portion (680) enlarging a clearance between the outer peripheral surface of the ring insertion portion (620) and the inner peripheral surface of the casing is formed at a position shifted in the axial direction with respect to the outside ring seal portion.
  11. The compressor according to any one of Claims 1 to 10, further comprising a movement-holding portion (700) capable of allowing a discharge side head as one of the heads disposed at the position close to the discharge port (35) to move relative to the casing in the axial direction and capable of holding the position of the discharge side head at any position in the axial direction, wherein the movement-holding (700) portion holds the position of the discharge side head (14) at a position where the discharge side head is farthest from the plurality of diaphragms (13) and where the discharge side head is immovable toward the outside in the axial direction as the side opposite to the side where the plurality of diaphragms (13) is disposed.
  12. The compressor according to Claim 11, wherein the movement-holding portion (700) includes: a fixed member (710) having a fixed member communication hole (711) communicating in the axial direction and fixed to the discharge side head; a shaft member (720) having an outer peripheral surface provided with a male screw and one end fixed to the casing in a state where the shaft member is inserted in the fixed member communication hole; a first nut (730) in which a female screw is formed, the first nut being movable relative to the shaft member in a state where the shaft member is inserted in the first nut and disposed on the casing side in the axial direction with respect to the fixed member; and a second nut (740) in which a female screw is formed, the second nut being movable relative to the shaft member in a state where the shaft member is inserted in the second nut and disposed on a side opposite to the first nut with respect to the fixed member.
  13. The compressor according to any one of Claims 1 to 12, wherein a wire insertion portion (900) allowing a wire (504) for lifting or lowering which is able to be rolled up by a crane to be inserted is formed at a lower end of one of the heads in the vertical direction.
  14. A compressor-manufacturing method for manufacturing a compressor according to any one of Claim 1 to 13, the method comprising: a casing preparation step of preparing a casing including an upper half casing (21, 21A, 21B, 21F) having an upper half casing-divided surface (211) as a horizontal surface facing downward in a vertical direction and a lower half casing (22, 22A, 22F) having a lower half casing-divided surface (221) capable of abutting against the upper half casing-divided surface (211), the casing having a tubular shape with both ends open; a bundle preparation step of preparing a bundle (10) including a plurality of impellers (112) rotatable about an axis (O), a plurality of diaphragms (13) in which in each of them, an impeller (112) is accommodated and a flow path introducing a fluid to a flow path of the impeller is formed, two annular heads (14) respectively fixed on both sides in an axial direction in which the axis extends with respect to the plurality of diaphragms (134) and closing openings of the casing, and a communication clearance seal portion (16) disposed in outer peripheral surfaces of the plurality of diaphragm; a bundle disposition step of accommodating the bundle (10) on an inner peripheral side of the lower half casing (22, 22A, 22F) by lowering the bundle (10) from above in the vertical direction with respect to the lower half casing (22, 22A, 22F) and forming a clearance extending in the axial direction such that a suction port through which a fluid flows in and a discharge port through which a fluid is discharged communicate with each other, wherein the clearance is formed between the outer peripheral surfaces of the plurality of diaphragms (13) and an inner peripheral surface of the lower half casing (22, 22A, 22F); and an upper half casing (21, 21A, 21B, 21F ) disposition step of disposing the upper half casing on the lower half casing (22, 22A, 22F) in which the bundle is accommodated, by lowering the upper half casing (21, 21A, 21B, 21F ) from above in the vertical direction with respect to the bundle and forming the clearance extending in the axial direction such that the suction port (23) and the discharge port (35) communicate with each other, wherein the clearance is formed between the outer peripheral surfaces of the plurality of diaphragms (13) and an inner peripheral surface of the upper half casing (21, 21A, 21B, 21F ) and abutting the upper half casing-divided surface against the lower half casing-divided surface, wherein the bundle (10) is disposed and the communication clearance seal portion comes into contact with the inner peripheral surface of the lower half casing (22, 22A, 22F) in a state where a position of one of the heads (14) is restricted in the axial direction with respect to the lower half casing (22, 22A, 22F)in the bundle disposition step; and the upper half casing (21, 21A, 21B, 21F )is disposed and the communication clearance seal portion comes into contact with the inner peripheral surface of the upper half casing (21, 21A, 21B, 21F ) in a state where the position of the one of the heads is restricted in the axial direction with respect to the upper half casing in the upper half casing disposition step.
  15. The compressor-manufacturing method according to Claim 14, further comprising: a head seal portion (15) preparation step of preparing a head seal portion (15) including an annular ring insertion portion (620) insertable between an outer peripheral surface of one of the heads (14) and an inner peripheral surface of the casing, an inside ring seal portion (670) capable of providing sealing between an inner peripheral surface of the ring insertion portion and the outer peripheral surface of the head (14), and an outside ring seal portion (630) capable of providing sealing between an outer peripheral surface of the ring insertion portion and the inner peripheral surface of the casing, the head seal portion (15) providing sealing between the head and the casing; and a head seal portion (15) movement step of bringing the inside ring seal portion (670) into contact with the inner peripheral surface of the ring insertion portion and the outer peripheral surface of the head and brining the outside ring seal portion (630) into contact with the outer peripheral surface of the ring insertion portion and the inner peripheral surface of the casing by moving the ring insertion portion in the axial direction from an outside of the head or the casing, the head seal portion (15) movement step being carried out after the upper half casing disposition step.
  16. The compressor-manufacturing method according to Claim 15, wherein the ring insertion portion is inserted between the outer peripheral surface of the head (14) and the inner peripheral surface of the casing (2, 2A, 2B, 2C, 2D, 2E, 2F) from an outside in the axial direction as a side opposite to a side where the plurality of diaphragms is disposed with respect to the head (14) or the casing (2, 2A, 2B, 2C, 2D, 2E, 2F) in the head seal portion (15) movement step.
  17. The compressor-manufacturing method according to any one of Claims 14 to 16, further comprising: a movement-holding portion (700) preparation step of preparing a movement-holding portion (700) capable of allowing a discharge side head as one of the heads disposed at a position close to the discharge port to move relative to the casing in the axial direction and capable of holding the position of the discharge side head at any position in the axial direction; a fixing release step of releasing the fixing of the discharge side head and one of the plurality of diaphragms, the fixing release step being carried out after the bundle (10) disposition step and before the upper half casing disposition step; and a discharge side head movement step of holding the position of the discharge side head after a movement by the movement-holding portion (700) to a position where the discharge side head (14) is farthest from the plurality of diaphragms (13) and the discharge side head is immovable toward the outside in the axial direction as the side opposite to the side where the plurality of diaphragms is disposed, the discharge side head movement step being carried out after the upper half casing disposition step.
  18. The compressor-manufacturing method according to Claim 17, wherein the discharge side head (14) and the diaphragm are fixed only at a position communicating with the outside in a state where the bundle (10) is disposed with respect to the lower half casing (22, 22A, 22F) in the bundle preparation step.

Description

Technical Field The present invention relates to a compressor and a compressor-manufacturing method. Background Art A centrifugal compressor allows gases to pass through a rotating impeller and compresses the gases using the centrifugal force generated at that time. A multistage centrifugal compressor is well-known as a centrifugal compressor, and is provided with a plurality of impellers that compress gases in stages. The centrifugal compressor as described above has a structure that is provided with a casing which is vertically divisible with a horizontally spreading divided surface. Specifically, the casing is configured by fastening a lower half casing installed on a floor surface and an upper half casing disposed on the lower half casing with bolt or the like. In the centrifugal compressor, a rotor is disposed to penetrate the casing. The rotor is rotatable with respect to the casing. PTL 1, for example, discloses a multistage centrifugal compressor provided with a diaphragm formed in an annular shape by an upper half diaphragm and a lower half diaphragm that have a semicircular ring shape being combined with each other. In this multistage centrifugal compressor, a plurality of the combined diaphragms are fixed and adjacent to each other in an axial direction in a vertically divisible casing. In addition, the outer peripheral surface of the diaphragm is provided with a vertically divisible ring member. The position of the diaphragm in the axial direction with respect to the casing is restricted by this ring member. PTL 2 also discloses a compressor that has a vertically divisible casing. In the compressor disclosed in PTL 2, an internal unit in which a diaphragm and a rotor are integrally formed is disposed in the vertically divisible casing. The internal unit is provided with a pair of heads disposed on both sides of the rotor in an axial direction to sandwich a plurality of the diaphragms and seal the openings at both ends of the casing. In addition, a plurality of fitting recessed portions are formed in the casing. The position of the diaphragm in the axial direction with respect to the casing is restricted by a plurality of fitting projecting portions formed in the diaphragm and the head fitting in this fitting recessed portion. In this manner, in the compressor as described above, a structure regulating the position of the diaphragm in the axial direction with respect to the casing is disposed between the inner peripheral surface of the casing and the outer peripheral surfaces of the plurality of diaphragms. Citation List Patent Literature [PTL 1] United States Patent No. 7513735[PTL 2] Japanese Unexamined Patent Application, First Publication No. 2013-72356[PTL 3]EP 3168443 A1.[PTL 4]US 2014/178183 A1[PTL 5]US 2015/016988 A1 Summary of Invention Technical Problem In a case where the casing has a vertically divided structure and the diaphragm therein is integrally formed, a clearance is formed between the inner peripheral surface of the casing and the outer peripheral surface of the diaphragm. When the diaphragm position-regulating structure is disposed simply in this clearance as in PTL 1 and PTL 2, a suction port and a discharge port are connected via the clearance. As a result, the difference between the pressures of the discharge and suction ports causes a fluid to flow into the clearance from the discharge port toward the suction port, and then fluid leakage may occur. Leakage reduction between the inner peripheral surface of the casing and the outer peripheral surface of the diaphragm is desirable. The present invention provides a compressor and a compressor-manufacturing method allowing leakage to be reduced between the inner peripheral surface of a casing and the outer peripheral surface of a diaphragm. Solution to Problem The invention provides a compressor according to claim 1 and a method of manufacturing such a compressor according to claim 14. Preferred embodiment of the invention are defined in the dependent claims. Advantageous Effects of Invention With the present invention, leakage can be reduced between the inner peripheral surface of a casing and the outer peripheral surface of a diaphragm. Brief Description of Drawings FIG. 1 is a sectional view schematically illustrating the configuration of a compressor according to a first embodiment.FIG. 2 is a schematic diagram schematically illustrating the compressor according to the first embodiment that is seen from one side in an axial direction.FIG. 3 is an enlarged view of a main part illustrating a welding portion of adjacent diaphragms according to the embodiment.FIG. 4 is an enlarged view of a main part illustrating a restricting portion and a head seal portion according to the first embodiment.FIG. 5 is a sectional view illustrating a clearance seal attachment groove and a communication clearance seal portion according to a core aspect of the present invention.FIG. 6 is an enlarged view of a main part illustrating a fastening po