JPH1054398A - Turbo compressor and rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve assembly, disassembly and maintainability by eliminating an influence of heat and deformation given to a motor case from a compression stage casing, and forming the motor case so that it can be set up from the vertical direction. SOLUTION: This compressor is constituted so as to have a motor case 8 storing a high speed motor M and compression stage casings 13, 14 respectively storing impellers 6, 7 by extending a rotor 2 of the high speed motor in both sides of a motor part 1 and providing the impellers 6, 7 in both shaft ends of the rotor 2. Here, the motor case 8 and both compression stage casings 13, 14 positioned in both sides thereof are respectively independently constituted, also a cooler case 15 is provided, the cooler case 15, lower casing 13b of the compression stage casing 13 and a lower casing 14b of the compression stage casing 14 are formed into an integral structure, the compression stage casings 13, 14 are formed in a horizontally divided structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbo compressor and a rotary machine, and more particularly to a motor which is hardly affected by a rise in the temperature of a compression stage, improves the stability of high-speed rotation of a rotor, and improves maintainability. The present invention relates to an improved high-speed motor driven turbo compressor and a rotary machine, and is mainly used for supplying oil-less compressed air.

[0002]

2. Description of the Related Art In recent years, a turbo compressor has been developed in which a rotor of a high-speed motor is overhanged and impellers are provided at both shaft ends of the rotor.
International "(Turbomachinery)
InternationalMarch / April
1994) and its product catalog "Sul
"Zer's catalog" discloses a gas compressor in which an impeller is mounted on a high-speed motor rotor supported by magnetic bearings.

A conventional turbo compressor using a high-speed motor will be described with reference to FIGS. FIG. 3 is a schematic configuration diagram showing a configuration of a conventional turbo compressor and a flow of gas, and FIG. 4 is a longitudinal sectional view showing an example of a conventional turbo compressor. The solid arrows in FIG. 3 indicate the gas flow. As shown in FIGS. 3 and 4, impellers 6 and 7 are attached to both ends of a rotor 2 driven by a motor unit 1 of a high-speed motor.
The rotor 2 is supported by radial bearings 3 and 4 and a thrust bearing 5. The motor unit 1, the rotor 2, and the bearings are housed in a motor case 8. The compression stage incorporating the impeller 6 is provided in the compression stage casing 9 and the impeller 7.
Is housed in a compression stage casing 10.

The motor case 8 and the compression stage casings 9 and 10 are integrally formed in the circumferential direction.
Therefore, the compression stage casings 9 and 10 are attached to the motor case 8 from the axial direction. That is, after the assembly is completed, as shown in FIG. 4, the motor case 8 and the compression stage casings 9 and 10 have an integrated structure in which they are connected.

If the impeller 6 is set to a low pressure stage and the impeller 7 is set to a high pressure stage, the gas compressed by the impeller 6 is discharged from the compression stage casing 9 once, cooled by the intercooler 11, and then compressed. It is sucked into the stage casing 10, compressed again by the impeller 7, compressed to a specified pressure, cooled by the aftercooler 12, and then supplied to the demand destination.

[0006]

However, such a compressor has the following problems. That is, when assembling the compressor, it is necessary to install the motor and then attach the compression stage casings 9 and 10 from the axial direction. At the time of disassembly, the compression stage casings 9 and 10 must be moved in the axial direction to a position where the tip of the rotor 2 comes off. Therefore, it takes time to disassemble and assemble.

[0007] Another problem is that when an impeller stage having a compression ratio exceeding 3 is required, the temperature of the casing wall surface becomes as high as over 150 ° C. On the other hand, if the bearing is a magnetic bearing, it is not preferable that high-temperature heat is transmitted to the bearing from the compression stage casing in order to maintain the insulation of the coil.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to eliminate the influence of heat and deformation from a compression stage casing on a motor case and to reduce the motor case. An object of the present invention is to provide a turbo compressor and a rotary machine which can be installed in a vertical direction and have improved assembling, disassembling, and maintenance.

[0009]

In order to achieve the above object, the most basic configuration of the turbo compressor according to the present invention is as follows.
The rotor of the high-speed motor is extended to both sides of the motor unit, and impellers are provided at both shaft ends of the rotor, and a motor casing for housing the high-speed motor and an impeller located at least at both shaft ends of the rotor are housed respectively. In the turbo compressor having two compression stage casings, the motor casing and the two compression stage casings located on both sides of the motor casing are configured independently of each other.

In order to achieve the above object, a more specific configuration of the turbo compressor according to the present invention is such that a rotor of a high-speed motor is extended to both sides of a motor portion, and impellers are provided at both shaft ends of the rotor. A motor casing for accommodating the high-speed motor, and two compression stage casings for accommodating at least impellers located at both shaft ends of the rotor, respectively. In a turbo compressor having a cooler and an outer cooler downstream of the compression stage casing on the high-pressure stage side of the two compression stage casings, the motor casing and the first and second stages located on both sides of the motor casing. The two cooling stage casings of the stage are configured independently of each other, and a cooler casing for accommodating the intercooler and the aftercooler. The provided, it is obtained by forming the integral structure with the lower casing of the first-stage compressing stage casing and lower casing of the cooler case and two-stage compression stage casing.

That is, the rotor of the high-speed motor is overhanged, and impellers are mounted on both shaft ends of the rotor.
In the multistage turbocompressor, the compression stage casing has an upper and lower half structure, and an intercooler case and an aftercooler case have a lower half of a one-stage compression stage casing and a lower half of a two-stage compression stage casing integrated. The compression lower casing is
The suction nozzle and / or the discharge nozzle are connected directly to the cooler case. No connecting portion such as a flange joint is provided between the lower casing and the cooler case.

A seat surface for installing a high-speed motor is provided on the upper surface of the cooler case. On the other hand, the motor case has an integral structure in the circumferential direction. However, a horizontal division structure may be used. The motor case has a rotor drive motor section,
The bearing and the rotor are housed. When the motor assembly and inspection are completed, the impeller is mounted on the rotor. Next, it is confirmed that the motor unit is complete.

The distance between the inner surfaces of the lower casing is slightly longer than the distance between the sides of the motor case. Alternatively, when the condition is not satisfied, the outer shape of the end portion of the motor case at the portion is prevented from being larger than the inner diameter of the axially overlapping portion with the compression stage casing. In this way, if the motor unit is installed on the seat surface on the upper surface of the cooler case from above in the vertical direction, the combination of the motor and the compression stage can be performed. Moreover, the temperature of the compression stage casing becomes high due to the compression work of the impeller. However, since the compression stage casing is separated from the motor, the heat is not easily transmitted to the motor case, and the bearing is protected.

Further, since the compression stage casing is formed integrally with the cooler, there is no fear of gas leakage in the gas passage. If a connection surface is provided between the compression stage casing and the cooler, a device that absorbs thermal deformation and seals the connection surface is required. However, such a device is not required in the present invention. The motor case does not receive an external force due to its own weight or thermal deformation of the compression stage casing, so that it is sufficient to drive the rotor independently. It should be noted that the combined portion of the motor case and the compression stage casing may be sealed with the atmosphere using an O-ring or the like to such an extent that the deformation is not restricted.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a partial cross-sectional front view of a turbo compressor according to an embodiment of the present invention, and FIG.
FIG. 3 is a side view taken along line AA of FIG. In the figures, those having the same reference numerals as those in FIGS. As shown in FIG.
A rotor 2, a motor unit 1 for driving the rotor 2, radial bearings 3, 4 for supporting the rotor 2, and a thrust bearing 5
Is housed in the motor case 8 at the center of the apparatus.

The rotor 2 of the high-speed motor M is extended to both sides of the motor unit 1 and overhangs, and impellers 6 and 7 are mounted on both shaft ends of the rotor 2. The compression stage using the impeller 6 is built in the compression stage casing 13 and the impeller 7
Is incorporated in the compression stage casing 14. The compression stage casing 13 is horizontally divided from the rotor axis into an upper casing 13a and a lower casing 13b, and the compression stage casing 14 is horizontally divided from the rotor axis into an upper casing 14a and a lower casing 14b. . And the lower casings 13b, 14b
It is integrally connected to the cooler case 15.

FIG. 2 is a view taken in the direction of arrows AA in FIG. 1, and shows the horizontal division structure of the compression stage casing and the integrated structure of the lower casing and the cooler. 2, 15a is an intercooler case, 15b is an aftercooler case, 11
a is a cooling water pipe (tube) flowing through the intercooler case 15a, and 12a is an aftercooler case 15a.
A cooling water pipe (tube) flowing through the inside b, and 19 indicated by a thick arrow indicate a gas flow supplied from the aftercooler to the demand side.

The cooler case 15 includes the intercooler 11
(See FIG. 3), an intercooler case 15a
And an aftercooler case 15b for accommodating the aftercooler 12 (see FIG. 3). And
Although not shown in detail here, the intercooler 11 is a so-called plate fin tube type including a cooling water pipe 11a and a plate fin, and
Reference numeral 2 denotes a so-called plate fin tube type which includes a cooling water pipe 12a and plate fins.

Lower casing 13 of compression stage casing 13
The connection between b and the intercooler case 15a of the cooler case 15 is made by a portion forming a one-stage (low-pressure stage) discharge nozzle. The connection between the lower casing 14b of the compression stage casing 14 and the intercooler case 15a and the aftercooler case 15b of the cooler case 15 forms a portion forming a two-stage (high-pressure stage) suction nozzle and a two-stage discharge nozzle. Made by pieces. In other words, the compression lower casings 13b and 14b are directly connected to the cooler case 15 at their suction nozzles and / or discharge nozzles. Lower casing 13b,
No connecting portion such as a flange joint is provided between the cooler case 15 and 14b.

As shown in FIG. 1, the compression stage casing 1
Sealing devices 16 and 17 are provided between the rotors 3 and 14 and the rotor 2 so that leakage of compressed gas is minimized. The motor case 8 of the high-speed motor M is installed on a seat 18 formed on the upper surface of the cooler case 15.

In this way, since the motor case 8 and the compression stage casings 13 and 14 are formed independently of each other, the compression stage casings 13 and 14 are formed by compression work.
Even if the temperature of 14 rises, it is hardly transmitted to the motor case 8, so that the bearing of the high-speed motor M can be protected. Further, since the motor case 8 is not directly affected by the heat deformation of the casing and the change of the alignment caused by the rise in the temperature of the gas, the high speed rotation of the rotor 2 is not adversely affected.

The distance between the inner side surfaces of the compression stage casings 13 and 14 is slightly longer than the distance between the side surfaces of the motor. Alternatively, as shown in FIG. 1, when the relationship cannot be established, the outer diameter of the motor case 8 is smaller than the inner diameter of the compression stage casing in the axially overlapping portion between the compression stage casings 13 and 14 and the motor case 8. It is constituted so that it may become. With this configuration, the high-speed motor M performs an assembly test independently, and further, after the impellers 6 and 7 are mounted, from above in the vertical direction, on the cooler case 15 between the compression lower casings 13b and 14b. It can be installed on the seat 18.

Thereafter, the compression lower casings 13b, 14
b, the compression stage upper casings 13a and 14a are assembled. Furthermore, the space between the compression stage casings 13 and 14 and the motor case 8 is sealed with an O-ring or the like so that the leakage flow of the labyrinth (not shown) of the compression stage casings 13 and 14 is not directly discharged to the atmosphere. .

The operation of such a turbo compressor will be described. Now, assuming that the impeller 6 is at the low pressure stage and the impeller 7 is at the high pressure stage, the gas compressed by the impeller 6 is once discharged from the compression stage casing 13 to the intercooler case 15 a, and the cooling water pipe 11 a is discharged by the intercooler 11. After being cooled by heat exchange with the flowing cooling water, it is sucked into the compression stage casing 14. Then, the gas is compressed again to the specified pressure by the impeller 7, discharged to the aftercooler case 15 b, cooled by exchanging heat with the cooling water flowing through the cooling water pipe 12 a by the aftercooler 12, and To the demand destination.

According to the present embodiment, the high-speed motor M is hardly affected by the rise in the temperature of the compressor stage, so that the stability of the high-speed rotation of the rotor 2 is improved. Then, since the high-speed motor M can be united as a unit and assembled to the compressor unit, workability is improved. During maintenance of the high-speed motor M, it is almost unnecessary to remove pipes, and the time for the maintenance work process can be reduced. Further, since the compressor stage casings 13 and 14 and the cooler case 15 are integrated, there is no danger of gas leakage.

In the above-described embodiment, the rotor of the high-speed motor is extended to both sides of the motor portion, impellers are provided at both shaft ends of the rotor, and a motor casing for housing the high-speed motor; Although the example of the turbo compressor having both the compression stage casings accommodating the impellers located at the shaft ends has been described, the present invention is not limited to the turbo compressor, and the rotor of the high-speed motor is extended to both sides of the motor unit. A rotating machine having impellers at both shaft ends of the rotor, and a motor casing that houses the high-speed motor, and a two-wheel impeller stage casing that houses at least the impellers located at both shaft ends of the rotor. It can be applied for general purposes.

[0027]

As described in detail above, according to the present invention, the effects of heat and deformation from the compression stage casing on the motor case are eliminated, and the motor case can be installed from the vertical direction. It is possible to provide a turbo compressor and a rotating machine that improve disassembly and maintenance.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional front view of a turbo compressor according to an embodiment of the present invention.

FIG. 2 is a side view taken along the line AA of FIG. 1;

FIG. 3 is a schematic configuration diagram showing a configuration of a conventional turbo compressor and a flow of gas.

FIG. 4 is a longitudinal sectional view showing an example of a conventional turbo compressor.

[Description of Signs] 1 ... motor part, 2 ... rotor, 3,4 ... radial bearing, 5
... thrust bearings, 6, 7 ... impeller, 8 ... motor case,
13, 14 ... compression stage casing, 13a, 14a ... upper casing, 13b, 14b ... lower casing, 15 ... cooler case, 15a ... intercooler case, 15b ... after cooler case, 16, 17 ... sealing device, 18 ...
seat.

Claims (6)

[Claims] 1. A motor casing for extending a rotor of a high-speed motor on both sides of a motor portion, having impellers at both shaft ends of the rotor, and accommodating the high-speed motor, and being located at least at both shaft ends of the rotor. A turbo compressor comprising: two compression stage casings each housing an impeller; wherein the motor casing and the two compression stage casings located on both sides of the motor casing are independently configured. . 2. A motor casing for extending a rotor of a high-speed motor on both sides of a motor portion, having impellers at both shaft ends of the rotor, and accommodating the high-speed motor, and being located at least at both shaft ends of the rotor. Two compression stage casings respectively accommodating the impeller, an intercooler provided in a flow path connecting the two compression stage casings, and an aftercooler in a downstream side of the compression stage casing on the high pressure stage side of the two compression stage casings. In a turbo compressor provided with a cooler, the motor casing, and both one-stage and two-stage compression stage casings located on both sides of the motor casing,
Independently configured, a cooler case for accommodating the intercooler and the aftercooler is provided, and the lower casing of the one-stage compression stage casing, the cooler case, and the lower casing of the two-stage compression stage casing are integrally formed. A turbo compressor characterized by the above-mentioned. 3. The turbo compressor according to claim 1, wherein the motor casing is formed integrally in a circumferential direction, and the compression stage casing is formed in a horizontal split type. 4. A turbo compressor according to claim 1, wherein a mounting seat surface of a motor casing is provided on an upper surface of the cooler case. 5. A motor casing for extending a rotor of a high-speed motor to both sides of a motor portion, having impellers at both shaft ends of the rotor, and accommodating the high-speed motor, and being located at least at both shaft ends of the rotor. A rotary machine having two impeller stage casings for respectively storing impellers, wherein the motor casing and the two impeller stage casings located on both sides of the motor casing are configured independently of each other. . 6. The rotary machine according to claim 5, wherein the motor casing is formed integrally in the circumferential direction, and the impeller step casing is formed in a horizontal split shape.