JPH09189298A - Compressor rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor rotor in which the crack of a disk and the unstable vibration of a rotor shaft may not occur. SOLUTION: A plurality of cylindrical holes 11 is opened in the rotor shaft direction at equal pitches to the circumferential direction by being opposed to a contact surface 10 between disks 6 provided adjacently to each other, pins 12 are inserted into these holes 11, a torque is transmitted even by these pins 12 so that occurrence of a slide which has generated on the contact surface 10 is prevented. Hereby, even though the work tolerance of a compressor rotor 20 and fastening accuracy is deviated from a designing conditions and an excessive transmission torque is generated by operation outside the designing conditions, the slide may not occur to the contact surface 10, occurrence of the crack of the disks 6 caused by this slide or the unstable vibration of the rotor shaft can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor rotor for supplying compressed combustion air to gas turbines, jet engines and the like.

[0002]

2. Description of the Related Art A gas turbine having a structure shown in FIG. 2 is used as a gas turbine for injecting fuel into compressed air supplied into a combustor to generate power. As shown in the figure, such a gas turbine compresses air A introduced from the atmosphere by a compressor 1 and injects a fuel F into a combustor 2 to which the compressed air is supplied to generate high temperature and high pressure. The combustion gas is generated and supplied to the turbine section 3 to generate power, and the generator 4 and the compressor 1 are driven by this power via the rotor shaft 17.

As shown in FIG. 3 (a), the compressor 1 used in such a gas turbine has a plurality of discs 6 having rotor blades 5 planted on the outer peripheral edge thereof, which are superposed on each other. In the circumferential direction of the central portion of each disk 6, through bolts 8 are axially passed through through-holes 7 provided at predetermined intervals, and the adjacent disks 6 are tightened to form a compressor rotor 20. I am trying to do it.
That is, the rotor shaft 17 is not penetrated through the central portion of the disc 6, and the rotor shaft 17 is provided on the outer surface of the discs 6 arranged at both ends of the discs 6 that are arranged so as to overlap each other. It is connected by a flange and is rotated by the driving force from the turbine unit 3 to compress the introduced air, and at the same time, the driving force is transmitted from the turbine unit 3 to the generator 4.

As described above, unlike the ordinary rotating body, since the rotor shaft 17 is not provided in the central portion so as to penetrate therethrough, the center of the compressor rotor 20 is centered, so that the central portion of the disk 6 has an inlay. 9 is provided. As a result, all torque loads transmitted from the turbine unit 3 via the rotor shaft 17 for driving the compressor rotor 20 are directed in the direction of the rotor shaft 17 by the frictional force of the contact surface 10 on the side surface of the adjacent disk 6. It is transmitted to each of the discs 6 that are overlapped.

However, in the compressor rotor 20 having such a structure, the weight is reduced, and the compressor rotor 20 can be easily attached to and removed from the rotor shaft 17, while the machining tolerance and tightening accuracy of the compressor rotor 20 are reduced. If the contact surface 10 does not have sufficient friction transmission torque for all torques due to deviation from design conditions during operation, a slight slip occurs on the contact surface 10 of the disk 6, and as a result, Fretting, that is, elastic strain is generated in the contact surface 10, and it is feared that fatigue and wear caused by fretting may cause cracks in the disk 6 and instability in vibration of the rotor shaft 17. .

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the conventional compressor rotor, the present invention solves the above-mentioned problems of the disc tolerance even if there are deviations from machining tolerances, tightening accuracy, or design conditions during operation. An object of the present invention is to provide a compressor rotor that does not cause cracks or instability in rotor shaft vibration.

[0007]

Therefore, the compressor rotor of the present invention has the following means.

(1) The discs arranged in parallel along the rotor axis are made to face each other at their contact surfaces with the adjacent discs, and are arranged at equal pitches in the circumferential direction of the discs in the rotor axial direction. A plurality of cylindrical holes provided with an axial center were provided. Although the holes are formed in the axial direction of the disc, it is preferable that the holes do not pass through the disc and the pitch is determined so that ten or more holes are provided in the circumferential direction of the disc.

(2) Cylindrical pins, which prevent slippage, are inserted into the cylindrical contact holes formed in the contact surfaces of the adjacent discs so as to be opposed to each other, and the contact surfaces are interconnected.

With the compressor rotor of the present invention, by means of the above-mentioned means (1) and (2), (1 ') even if the machining tolerance of the compressor rotor and the tightening accuracy deviate from the design conditions, Even when the operating conditions generate maximum torque, such as during an emergency stop, torque can be transmitted not only by the friction of the contact surface but also by the pin inserted in the hole of this contact surface. It is possible to prevent slippage on the contact surface between them. As a result, fretting can be prevented, cracks that may occur in the disk can be prevented, and instability in rotor shaft vibration does not occur.

Further, the compressor rotor of the present invention according to claim 2 has the following means in addition to the above-mentioned means (1) and (2).

(3) A dozen or more holes in the axial direction of the rotor provided in the contact surface of the disk are provided in the contact surface on the outflow side of the air passing through the disk, and the outflow side hole has the same diameter as the pin diameter. Round holes,
The inflow side hole provided on the inflow side contact surface has the same pin diameter as the outflow side hole in the circumferential direction of the disc, and in the radial direction of the disc an oblong hole longer than the pin diameter. did. Note that the oblong holes of the inflow side holes are formed in the discs at each stage, which are arranged so that the radial length of the discs is about 0.5 mm longer than the circumferential length, and the discs are superposed in the turbine axial direction. It is preferable that the displacement difference in the radial direction can be absorbed by the radial length of the oblong hole.

According to the compressor rotor of the present invention, in addition to the above-mentioned (1 '), (2') by means of the above-mentioned (3), between the adjacent disks of the disks arranged in parallel in the rotor axial direction. Even if a displacement difference occurs in the radial direction due to a difference in temperature, a weight deflection of the rotor shaft, or the like, the difference can be absorbed by the oval hole portion, and the bending load generated in the pin can be reduced. As a result, it is possible to reliably prevent slippage that has conventionally occurred at the contact surface between the disks, and to prevent cracks that occur on the disks or unstable vibration of the rotor shaft, and By reducing the bending load that occurs, the diameter of the pin can be made smaller, and consequently the rigidity of the disc due to the formation of the hole for inserting the pin can be reduced.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a compressor rotor of the present invention will be described below with reference to the drawings.

FIG. 1 (a) is a vertical sectional view showing a first embodiment of a compressor rotor of the present invention, and FIG. 1 (b) is a front view taken along the line A--A shown in FIG. (C) is A of FIG.
A detailed view of the part and FIG. 1D are front views taken along the line BB shown in FIG. In these figures, the same reference numerals as those shown in FIG. 3 are the same or similar members, and detailed description thereof will be omitted.

As shown in the drawing, a plurality of discs 6 which are superposed and arranged in parallel in the direction of the rotor shaft 17 do not penetrate the rotor shaft 17 shown in FIG.
As shown in (b), through holes 7 provided at equal pitches are inserted in the circumferential direction of the circular plate 6, and the circular plates 6 are integrated by bolts 8 which are tightened to each other, and a compressor is provided. The rotor 20 is formed. The compressor rotor 20 formed in this manner has the rotor shaft 17 from the turbine section 3 and the rotor shaft 17 from the turbine section 3 formed by the flanges fixed to the outer surfaces of the disks 6 arranged on both sides of the disks 6 arranged in parallel. Each is connected to a rotor shaft 17 that is connected to the generator 4.

Further, as shown in FIG. 1 (a), the bolt 8
In the contact surface 10 provided on both side surfaces of the disk 6 in the circumferential direction on the outer circumferential side from the position where the pin is inserted, ten or more cylindrical holes 15 are axially formed at equal pitches, and the pins 12 are provided therein. The contact surface 10 is inserted even when the maximum torque is generated during an emergency stop or the like.
In addition to the torque transmission by friction in the above, the torque transmitted by the shearing force applied to the pin 12 can be transmitted from the rotor shaft 17 to the disc 6 without slipping on the contact surface 10. I am able to do it.

Further, as shown in FIG. 1 (c), a dozen or more axial holes 11 provided on the contact surface 10 are provided on the contact surface 10 on the outflow side of (compressed) air passing through the disc 6. The outflow side hole 13 provided is a closed round hole having the same diameter as the diameter of the pin 12 to be inserted, and the inflow side hole 14 provided in the contact surface 10 on the inflow side of the disc 6 is shown in FIGS. ), The disk 6
The diameter of the outflow side hole 13 is the same as the diameter of the outflow side hole 13, that is, the diameter of the pin 12, and the diameter of the outflow side hole 13 is the diameter of the pin 12 in the radial direction of the disc 6. It is an oval hole that is larger by about 0.5 mm.

As a result, the difference in displacement in the radial direction of the disk 6 at each step can be absorbed by the oblong hole portion provided in the inflow side hole 14, and the pin 12 can be urged without applying a large bending load. Maximum torque at the time of stopping can be transmitted by the pin 12 inserted in the hole 11.

In the conventional compressor rotor 20 for a gas turbine or the like, as shown in FIG. 3, a circular plate 6 is provided with ten or more through holes in the circumferential direction at a certain pitch, through which through bolts are tightened, Due to the frictional force at the contact surface of the plate 6, all the torque load transmitted from the rotor shaft 17 to the disc 6 or from the disc 6 to the rotor shaft 17 was transmitted. The torque transmission when the maximum torque is generated due to the attachment accuracy and the deviation from the design condition at the time of operation cannot be sufficiently transmitted from the turbine portion 3 to the disk 6 only by the frictional force at the contact surface 10, and the adjacent torque cannot be transmitted. Fatigue and wear occur due to the slight slippage on the contact surface of the circular plate 6 and the accompanying elastic strain in the coupled state, that is, fretting, resulting in cracking of the circular plate 6 and rotor shaft vibration. Instability may occur There had been concern.

However, in the present embodiment, as described above, the contact surface 10 of the disc 6 is provided with a dozen or more axial holes 11 in the circumferential direction, and the pins 12 are inserted therein. Therefore, even when the maximum torque is generated, not only the torque can be transmitted by friction on the contact surface 10, but also the torque can be transmitted by the pin 12, so that the occurrence of slippage on the contact surface 10 can be prevented. Also, an axial hole 11 provided in the contact surface 10
Indicates that the outflow side hole 13 is a closed round hole having the same diameter as the pin diameter, and the inflow side hole 14 is an elongated round hole portion that is long in the radial direction. The difference can be absorbed by the oval hole portion, the shearing force generated in the pin 12 is reduced, and the bending load applied to the pin 12 is reduced.

[0022]

As described above, according to the compressor rotor of the present invention, due to the structure shown in the claims, (1) the machining tolerance of the compressor rotor and the tightening accuracy deviate from the design conditions. However, even if the operating conditions are such that the maximum torque is generated during an emergency stop, the torque transmitted from the rotor shaft to the disc is transmitted by friction due to the side faces of the disc contacting each other. Not only that, but it can be transmitted by the pin inserted into the hole provided in the contact surface, and it is possible to prevent slippage in the contact surface that may occur between the disks. As a result, it is possible to prevent the occurrence of fretting, prevent the crack that may occur in the disc, or prevent the unstable phenomenon of vibration that may occur in the rotor shaft.

(2) Further, the shape of the hole provided on the contact surface of the disk for inserting the pin is such that the diameter of the outflow side hole is the same as that of the pin, and the outflow side hole has a hole of the same diameter as the pin. By adopting a large oval hole in the radial direction, even if there is a difference in displacement in the radial direction due to differences in temperature between adjacent disks and weight deflection of the rotor shaft, this oval hole can absorb the difference. The pin is not subjected to a strong bending load. As a result, the diameter of the pin and the size of the hole can be reduced, and in particular, the reduction in rigidity of the disc due to the drilling of the hole can be reduced.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a compressor rotor of the present invention, FIG. 1 (a) is a vertical cross section of the compressor rotor, and FIG.
1 is a front view in the direction of arrow AA shown in FIG.
1C is a detailed cross-sectional view of the portion A in FIG. 1A, FIG. 1D is a front view taken along the line BB shown in FIG.

FIG. 2 is a block diagram showing the configuration of a gas turbine,

3 is a diagram showing an example of a conventional compressor rotor, and FIG.
3A is a vertical cross-sectional view, and FIG. 3B is a front view taken along the line CC shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Combustor 3 Turbine 4 Generator 5 Blade 6 Disc 7 Through hole 8 Bolt 9 Inlay 10 Contact surface 11 Hole 12 Pin 13 Outflow side hole 14 Inflow side hole 17 Rotor shaft 20 Compressor rotor

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Katsuhisa Fujita 2-1-1, Niihama, Arai-cho, Takasago-shi, Hyogo Mitsubishi Heavy Industries Ltd. Takasago Research Institute

Claims (2)

[Claims] 1. A plurality of discs having rotor blades planted on the periphery thereof are arranged in parallel along a rotor shaft, and bolts are inserted into through holes provided at equal pitches in the circumferential direction of each disc. In the compressor rotor configured to form a rotor by tightening, a plurality of cylindrical holes facing each other on the contact surfaces of the adjacent disks and provided in the rotor axial direction at equal pitches in the circumferential direction, A compressor rotor provided with a pin that is inserted into a hole and that prevents the adjacent contact surfaces from slipping. 2. The air passing through the disc, wherein the outflow-side hole provided on the outflow-side side face of the air passing through the disc is formed into a tight round hole having the same diameter as the pin to be inserted. 2. The compressor rotor according to claim 1, wherein the inflow side hole formed on the inflow side surface of the compressor is an oblong hole in which the outflow hole is elongated in the radial direction of the disc.