JPH08232893A - Centrifugal compressor - Google Patents

Abstract

PURPOSE: To heighten space use efficiency and to reduce the size of a centrifugal compressor by making a narrow part of a suction volute and a wide part of a discharge volute adjacent to each other through a partition wall, and making a wide part of the suction volute and a narrow part of the discharge volute adjacent to each other through the partition wall. CONSTITUTION: A gas passage of a suction volute 3 is gradually decreased in its axial width as it separates from a suction nozzle so that the flow velocity of gas is constant, and on the other hand, a gas passage of a discharge volute 2 is gradually increased in its axial width as it approaches a discharge port so that the flow velocity of gas is constant. A narrow part of the suction volute 3 and a wide part of the discharge volute 2 are adjacent to each other through a partition wall 1A, and a wide part of the suction volute 3 and a narrow part of the discharge volute 2 are adjacent to each other through the partition wall 1A. Thus, the space use efficiency can be increased so as to reduce the size and weight of the compressor.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a centrifugal compressor.

[0002]

2. Description of the Related Art FIG. 3 is a vertical sectional view of an example of a conventional centrifugal compressor, FIG. 4 is a vertical sectional view of another example of a conventional centrifugal compressor, and FIG.
FIG. 6 is a sectional view taken along line BB in FIGS. 3 and 4. Since the shape of the BB cross section is the same, the cross sectional view (FIG. 5) is common to FIG. 3 and FIG. In the figure, 1 is a casing, 1A is a partition wall inside the casing, 1B is a guide, 2 is a discharge volute, 3 is a suction volute, 5 is a rotary shaft, 4 is an impeller attached to the rotary shaft, and 6 is a diaphragm. , 7 is a labyrinth, 8 (FIG. 5) is a suction nozzle, and 9 is a diffuser.

In the conventional stage structure of a centrifugal compressor, the suction volute 3 and the discharge volute 2 are axially arranged as shown in FIG. 3 or a radius is provided as shown in FIG. 4 via a partition wall 1A. It was arranged with the position shifted in the direction. Conventionally, the axial width of the suction volute 3 is
Since all of them have the same size on the same radius from the center of the rotary shaft 5, as a device for shortening the outer diameter, the discharge volute 2 is arranged so that the positions of the discharge volute 2 and the suction volute 3 do not interfere with each other as shown in FIG. It was made to inflate in the direction opposite to the suction volute 3. On the other hand, as a device for shortening the axial length, as shown in FIG. 4, the discharge volute 2 is provided outside the suction volute 3 in the radial direction so that the positions of the discharge volute 2 and the suction volute 3 do not interfere with each other.

Further, as shown in FIG. 5, the conventional suction volute 3 has a shunt type structure having a gas passage in which the gas sucked from the suction nozzle 8 is divided into two along the casing 1 into right and left.

[0005]

In the case of the arrangement shown in FIG. 3, the casing 1 has an axially long structure, and in the case of the arrangement shown in FIG. 4, it has a large radial structure. Therefore, conventionally, the casing 1 becomes long and large in diameter and becomes large in size, which is an obstacle to reduction in size and weight. The present invention aims to solve the above-mentioned drawbacks of the prior art and to provide a centrifugal compressor having a stage structure capable of miniaturization with high space utilization rate.

[0006]

DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned problems, in which a suction volute and a discharge volute are provided along the inside of the circumferential portion of the casing, and these volutes pass through a partition wall. In adjacent centrifugal compressors, each of the above volutes is a spiral volute in which the gas flows in one direction, and the suction volute has a shape in which the axial width gradually decreases as it moves away from the suction nozzle along the flow path. And the discharge volute
Along the flow path, the axial width gradually increases as it approaches the discharge port, and the narrow part of the suction volute and the wide part of the discharge volute are placed next to each other through the partition wall to reduce the width of the suction volute. The present invention relates to a centrifugal compressor characterized in that a wide portion and a narrow portion of a discharge volute are adjacent to each other via a partition wall.

[0007]

In the centrifugal compressor according to the present invention, the casing structure described above is combined so as to complement the large and small flow passage widths.
Space utilization is high, and therefore the centrifugal compressor can be downsized. This can reduce the weight.

[0008]

1 is a vertical sectional view of a centrifugal compressor according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA of FIG. Reference numerals and member names are the same as those described in the section of the related art. That is, the impeller 4, which is fixed to the rotating shaft 5, the suction volute 3, the discharge volute 2, the diaphragm 6, the labyrinth 7 which is fixed to the diaphragm 6, and the diffuser 9 are provided inside the casing 1 including the partition wall 1A, and A suction nozzle 8 for sucking air is attached to the casing 1.

In this apparatus, the gas that has entered the casing 1 from the suction nozzle 8 is guided to the guide 1B while flowing through the suction volute 3 and introduced into the impeller 4. Impeller 4
The gas pressurized by is discharged to the discharge side through the diffuser 9 and the discharge volute 2. Further, the diaphragm 6 and the partition wall 1A are partitioned so that the pressurized gas does not mix with the gas on the suction side of the impeller 4.

The features of this centrifugal compressor are as follows. (1) The suction volute 3 has a spiral structure having a gas passage in one direction along the inner peripheral surface of the casing 1 from the suction nozzle 8 as shown in FIG. (2) In the gas passage of the suction volute 3, the axial width of the gas passage is gradually reduced with increasing distance from the suction nozzle 8 so that the flow velocity of the flowing gas is constant. The axial width of the gas passage must be gradually increased as it approaches the discharge port (not shown) so that the flow velocity is constant. (3) As shown in FIG. 1, the narrow width portion of the suction volute 3 and the wide width portion of the discharge volute 2 are adjacent to each other through the partition wall 1A, and the wide width portion of the suction volute 3 and the discharge volute 2 are connected to each other. The narrow parts are adjacent to each other via the partition wall 1A.

Since the centrifugal compressor of this embodiment has the above-mentioned structure, it has high space utilization and can be made compact and lightweight.

[0012]

In the centrifugal compressor of the present invention, suction /
Each of the discharge volutes is a spiral volute in which gas flows in one direction, and the suction volute has a shape in which the axial width gradually decreases as the distance from the suction nozzle is increased along the flow path, and the discharge volute is changed along the flow path. The shape is such that the axial width gradually increases as it approaches the discharge port, and the narrow part of the suction volute and the wide part of the discharge volute are placed next to each other through a partition wall, and the wide part of the suction volute and the discharge volute Since the narrow part of the is adjacent to each other through the partition wall, it is possible to reduce the size and weight.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a centrifugal compressor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a vertical sectional view of an example of a conventional centrifugal compressor.

FIG. 4 is a vertical cross-sectional view of another example of a conventional centrifugal compressor.

5 is a sectional view taken along line BB of FIGS. 3 and 4. FIG.

[Explanation of symbols]

 1 Casing 1A Partition wall 1B Guide 2 Discharge volute 3 Suction volute 4 Impeller 5 Rotating shaft 6 Diaphragm 7 Labyrinth 8 Suction nozzle 9 Diffuser

Claims (1)

[Claims] 1. A centrifugal compressor in which a suction volute and a discharge volute are provided along an inner side of a circumferential portion of a casing, and the volutes are adjacent to each other through a partition wall. A spiral volute in which gas flows in one direction, the suction volute has a shape in which the axial width gradually decreases as it moves away from the suction nozzle along the flow path, and the discharge volute gradually increases as it approaches the discharge port along the flow path. With a shape that increases the axial width, the narrow part of the suction volute and the wide part of the discharge volute are placed next to each other through a partition wall, and the wide part of the suction volute and the narrow part of the discharge volute are Centrifugal compressor characterized in that they are side by side through a partition wall.