CENTRIFUGAL COMPRESSOR AND SEAL UNIT

• US 20200132078A1
• Filed: 10/24/2019
• Published: 04/30/2020
• Est. Priority Date: 10/26/2018
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries Compressor Corporation (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Mitsubishi Heavy Industries Compressor Corporation (Mitsubishi Heavy Industries, Ltd.)
• Inventors: Shakuda, Masaki, Tokuyama, Shinichiro
• Granted Patent: US 11,371,512 B2
• Time in Patent Office: Days
• CPC Class Codes: F04D 17/10 for compressing or evacuating
• CPC Class Codes: F04D 29/083 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/162 of a centrifugal flow wheel

Abstract

A centrifugal compressor includes a housing 20 having a facing surface 22f facing the outer peripheral surface of a cover 43, a seal member 50 forming a clearance with the outer peripheral surface of the cover 43, an inclined hole 55 formed in the seal member 50, extending at an angle to the side opposite to a direction of rotation, and having an opening portion 57 opening at a position facing the outer peripheral surface of the cover 43, a first fin 52 provided on the seal member 50 and protruding toward the outer peripheral surface of the cover 43, and a communication flow path portion 64 formed in the housing 20, having an introduction port 66i opening at a position facing the outer peripheral surface of the cover 43, and communicating with the inclined hole 55.

Claims

1. A centrifugal compressor comprising:

a rotary shaft which is configured to rotate around an axis;

an impeller having a disk fixed to the rotary shaft, a plurality of blades provided on a surface of the disk facing a first side in an axial direction and provided at intervals in a circumferential direction around the axis, and a cover provided on the first side in the axial direction with respect to the disk and the blade and having an outer peripheral surface extending outward in a radial direction toward a second side in the axial direction;

a housing covering the rotary shaft and the impeller, and having a facing surface formed on the first side in the axial direction with respect to the outer peripheral surface and facing the outer peripheral surface;

a seal member forming a clearance with the outer peripheral surface inward of the facing surface in the radial direction in the housing;

a plurality of inclined holes formed at intervals in the circumferential direction with respect to the seal member, respectively extending at an angle to a side opposite to a direction of rotation of the rotary shaft toward an inner side in the radial direction, and having an opening portion opening at a position facing the outer peripheral surface;

a first fin disposed on the seal member on the second side in the axial direction with respect to the opening portion, and protruding from the seal member toward the outer peripheral surface; and

a communication flow path portion formed in the housing, having an introduction port opening at a position facing the outer peripheral surface inward in the radial direction of an outer peripheral end on an outermost side in the radial direction in the cover, and communicating with the plurality of inclined holes.

2. The centrifugal compressor according to claim 1, wherein

the housing has a housing main body, and a seal holder detachably provided from the housing main body and holding the seal member, and

the communication flow path portion is formed in the seal holder.

3. The centrifugal compressor according to claim 1, wherein the communication flow path portion has a circumferential flow path continuous in the circumferential direction and communicating with the plurality of inclined holes, and a plurality of introduction flow paths connecting the introduction port and the circumferential flow path.

4. The centrifugal compressor according to claim 1, further comprising a second fin provided on the seal member on the first side in the axial direction with respect to the opening portion and protruding from the seal member toward the outer peripheral surface.

6. The centrifugal compressor according to claim 2, wherein the communication flow path portion has a circumferential flow path continuous in the circumferential direction and communicating with the plurality of inclined holes, and a plurality of introduction flow paths connecting the introduction port and the circumferential flow path.

7. The centrifugal compressor according to claim 2, further comprising a second fin provided on the seal member on the first side in the axial direction with respect to the opening portion and protruding from the seal member toward the outer peripheral surface.

8. The centrifugal compressor according to claim 3, further comprising a second fin provided on the seal member on the first side in the axial direction with respect to the opening portion and protruding from the seal member toward the outer peripheral surface.

9. The centrifugal compressor according to claim 6, further comprising a second fin provided on the seal member on the first side in the axial direction with respect to the opening portion and protruding from the seal member toward the outer peripheral surface.

5. A seal unit to be mounted onto a centrifugal compressor including a rotary shaft rotating around an axis, an impeller having a disk fixed to the rotary shaft, a plurality of blades provided on a surface of the disk facing a first side in an axial direction and provided at intervals in a circumferential direction around the axis, and a cover provided on the first side in the axial direction with respect to the disk and the blade and having an outer peripheral surface extending outward in a radial direction toward a second side in the axial direction, and a housing covering the rotary shaft and the impeller and having a facing surface formed on the first side in the axial direction with respect to the outer peripheral surface and facing the outer peripheral surface, the seal unit comprising:

an annular seal member allowed to be disposed so as to form a clearance with the outer peripheral surface inward of the facing surface in the radial direction in the housing;

a plurality of inclined holes formed at intervals in the circumferential direction with respect to the seal member, respectively extending at an angle in the circumferential direction toward an inner side in the radial direction, and having an opening portion opening on an inner peripheral surface of the seal member; and

a first fin disposed on the seal member on the second side in the axial direction with respect to the opening portion and protruding from the seal member,

wherein the plurality of inclined hole are communicable with a side inward in the radial direction of an outer peripheral end on an outermost side in the radial direction in the cover.