JPH1089009A - Steam turbine balance weight mounting device - Google Patents

Abstract

(57) [Problem] To improve the workability by eliminating the need to break the vacuum in the turbine casing in the installation or removal of the balance weight, and performing the installation and removal of the balance weight in a shorter time. Plan. A plurality of balance weight mounting portions are provided at intervals on a downstream stage side end of a rotor of a steam turbine low pressure portion along a circumferential direction. A balance weight 8 for stabilizing the rotation of the rotor is selectively detachably attached to the balance weight attachment portion 7. A balance weight storage section is provided in a stationary section close to the balance weight mounting section, and the balance weight is stored therein so as to be insertable and removable. The balance weight storage unit 2 is provided on the wall 25 of the turbine casing 1.
A small-diameter attachment / detachment insertion hole 26 that opens toward 4 is formed, and an opening / closing plug is detachably provided in this attachment / detachment insertion hole 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for attaching a balance weight to a rotor of a steam turbine low-pressure section, and more particularly to a technique of a steam turbine in which the balance weight can be easily attached and detached without breaking a vacuum state in a turbine casing. The present invention relates to a balance weight mounting device.

[0002]

2. Description of the Related Art FIG. 10 is a sectional view schematically showing a general configuration example of a low pressure section of a steam turbine. As shown in this figure, the steam turbine low-pressure section accommodates a rotor 3 having a moving blade 2 in a turbine casing 1 connected to a condenser (not shown), and corresponds to the moving blade 2 of the rotor 3 and the rotor 3. The arrangement of the stationary blades 4 forms a turbine stage.

[0003] A steam inlet 5 is provided at the center of the turbine casing 1, and drive steam flows into the turbine casing 1 through the steam inlet 5, and a plurality of steams composed of a stationary blade 4 and a moving blade 2 are provided. In the paragraph, the heat energy is converted to velocity energy while lowering the steam pressure to perform the work of rotating the rotor, and then sent to a condenser (not shown) through the low-pressure casing outlet side exhaust port 6. .

[0004] The rotor 3 rotates by receiving high-speed steam ejected from the stationary blades 4 by the moving blades 2, whereby the steam pressure at the steam inlet 5, for example, 10 ata, is reduced to the low pressure connected to the condenser. In the vicinity of the casing outlet side exhaust port 6, the pressure drops to 0.05 ata (vacuum degree 722 mmhg) lower than the atmospheric pressure.

As described above, the high-speed rotation of, for example, 3600 rpm is performed while the internal pressure of the turbine casing 1 is maintained at a vacuum degree such as 722 mmhg lower than the atmospheric pressure.
For this reason, if the rotation of the rotor 3 is unbalanced, vibration occurs in the rotor 3 and it becomes difficult to operate at high speed.

Conventionally, when such an imbalance has occurred, the following structure is attached to a predetermined one of the plurality of balance weight mounting portions 7 provided over the entire periphery of the downstream stage end of the rotor 3. The balance weight is mounted to balance the weight around the axis of the rotor 3 so that stable rotation can be performed.

FIG. 11 is an enlarged sectional view showing a structure near the balance weight attaching portion 7 of the rotor 3 of the turbine low pressure portion according to the prior art. FIG. 12 shows a state where the balance weight 8 is attached to the balance weight attaching portion 7. It is sectional drawing which expands and shows it further.

As shown in these figures, a plurality of threaded hole-shaped balance weight mounting portions 7 are provided at intervals on the downstream stage side end of the rotor 3 along the circumferential direction. A balance weight 8 having a screw structure for stabilizing the rotation of the rotor is selectively screwed into the mounting portion 7 so as to be detachably mounted. A cone 9 is provided around the balance weight mounting portion 7 in a structure that can be attached to and detached from the turbine casing 1, and a manhole 10 is formed in the turbine casing 1 so as to face the outer peripheral side of the cone 9. The manhole 10 is closed by a removable lid 11.

FIG. 13 is an enlarged front view showing a general structure of the balance weight 8, FIG. 14 is a bottom view thereof (a view in the direction of arrow A in FIG. 13), and FIG. 13 is a view in the direction of arrow B in FIG. 13).

As shown in these figures, the balance weight 8 has a cylindrical body 13 having an external thread 12 on its outer peripheral surface.
A pin 14 having a circular cross section protruding coaxially at the center position of one end (tip) in the axial direction of the body 13, and a square section formed at the surface center position of the other end (base end) in the axial direction of the body 13 And the concave portion 15.

FIG. 16 is a front view showing the structure of an attachment / detachment tool 16 for attaching / detaching the balance weight 8, and FIG.
FIG. 7 is a bottom view (view in the direction of arrow C in FIG. 16).

As shown in these figures, the attachment / detachment tool 16
At the center position of one end (tip) of the cylindrical rod 17 in the axial direction, a convex portion 18 having a rectangular cross section that fits into the concave portion 15 of the balance weight 8 is provided, and the other end (base end) of the rod 17 in the axial direction is provided. And a handle 19. By rotating the rod 17 in one direction via the handle 19 in a state where the projection 18 of the attachment / detachment 16 is fitted into the recess 15 of the balance weight 8, the balance weight 8 is attached to the balance weight attachment portion 7. It is attached by screwing in or removed by rotating in the opposite direction.

In the above conventional construction, when the balance weight 8 is to be attached or detached, the turbine rotor is first stopped, and then the vacuum break valve (not shown) provided on the condenser is opened. By doing so, the vacuum inside the turbine casing 1 is broken, and the pressure inside the turbine casing 1 is made equal to the atmospheric pressure.

Next, after opening the cover 11 of the manhole 10 of the turbine casing 1 shown in FIG. 11, a worker enters the turbine casing 1 and disassembles and removes the cone 9 in the turbine casing 1 and then removes the rotor 3. The balance weight 8 carried by the worker is mounted on the balance weight mounting portion 7 of the first embodiment.

After completion of the weight attachment, the cone 9
After the worker comes out of the manhole 10, the lid 11 is assembled.
Is closed, the operation of increasing the degree of vacuum inside the turbine casing 1 is performed, and the increase in the vacuum inside the condenser and the turbine casing 1 is completed. Thereby, the operation of the steam turbine can be restarted.

[0016]

According to the above-mentioned prior art, in the operation of mounting the balance weight 8,
Since the worker needs to enter the inside of the turbine casing 1 from the manhole 10, it is necessary to break the vacuum inside the turbine casing 1 in advance and raise the vacuum again after attaching the balance weight 8. For this reason, conventionally, due to the structure in the vicinity of the balance weight mounting portion 7, a large amount of time is required for vacuum breaking and increasing the degree of vacuum in the work of mounting the balance weight, resulting in low workability.
This also applies to the operation of removing the attached balance weight when the rotor rotation becomes unbalanced after the balance weight 8 is once attached.

The present invention has been made in view of such circumstances, and it is not necessary to break the vacuum in the turbine casing in the work of mounting or removing the balance weight, and the work of mounting and removing the balance weight can be performed in a shorter time. It is an object of the present invention to provide a steam turbine balance weight mounting device capable of improving workability.

[0018]

In order to achieve the above object, according to the first aspect of the present invention, a plurality of balance weight mounting portions are provided along the circumferential direction at the downstream stage side end of the rotor of the low pressure section of the steam turbine. In a steam turbine balance weight mounting device, which is provided at intervals, and in which a balance weight for stabilizing the rotation of the rotor is selectively removably mounted on these balance weight mounting portions, the balance weight is fixed to a stationary portion near the balance weight mounting portion. A weight storage unit is provided to store the balance weight therein so that the balance weight can be inserted and removed, and a small-diameter attachment / detachment insertion hole that opens toward the balance weight storage unit is formed in the wall of the turbine casing. A steam turbine balance weight mounting device characterized in that an opening / closing plug is detachably provided in the insertion hole. To provide.

According to a second aspect of the present invention, in the steam turbine balance weight mounting apparatus according to the first aspect, the balance weight is configured to be screwed into the balance weight mounting portion. A balance weight mounting device for a steam turbine, wherein the balance weight storage section and the attachment / detachment mounting hole are arranged on the same axis.

According to a third aspect of the present invention, in the steam turbine balance weight mounting apparatus of the first or second aspect, the balance weight storage section and the mounting / dismounting tool insertion hole communicate with each other via a hole or a cylinder. Provided is a steam turbine balance weight mounting apparatus, characterized in that:

According to a fourth aspect of the present invention, there is provided the steam turbine balance weight mounting apparatus according to the third aspect, wherein the balance weight storage unit and the attachment / detachment insertion hole communicate with each other via a cylinder. The outer cylinder in a fixed state and an inner cylinder inserted in the outer cylinder so as to be slidable in the axial direction have a double structure. On the other hand, the balance weight has a square convex portion at the front end and a rear end. It is characterized by having a rectangular concave portion, a plurality of things are connected in the axial direction by fitting the convex portion and the concave portion to each other, and are integrally rotatably inserted into the inner cylinder. To provide a steam turbine balance weight mounting apparatus.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The configuration of the low pressure section of the steam turbine is shown in FIG.
Therefore, FIG. 10 is referred to in the description of the embodiment of the present invention, and is described using the same reference numerals as those shown in FIG. Further, the same configuration as that described in the related art is applied to the balance weight and the attachment / detachment used in the following first embodiment and second embodiment, so that FIG. 13 to FIG. 17 are referred to as they are.

First Embodiment (FIGS. 1, 10, 13 to 13)
17) FIG. 1 is a sectional view showing a balance weight mounting device for a steam turbine according to the present embodiment.

In the present embodiment, as shown in FIG. 1, a plurality of threaded hole-shaped balance weight mounting portions 7 are provided at the downstream end of the rotor 3 of the steam turbine low-pressure section with respect to the axis of the rotor 3. Are arranged at intervals along the circumferential direction. That is, the openings of the holes as the balance weight mounting portions 7 are respectively set at the same distance from the rotor axis, and are inclined at the same angle from there toward the hole bottom.

A balance weight storage section 24 for storing the balance weight 8 is provided on a stationary portion close to the balance weight mounting section, for example, a rising wall 23 provided on the inner end side of a ground seal section 22 provided with a labyrinth packing 21 and the like.
Is provided. This balance weight storage unit 24
Are arranged so as to face the opening of the screw hole which is the balance weight mounting portion 7, and are screw holes of both ends opened coaxially on an extension of the axial center of the hole. Balance weight 8
13 (see FIGS. 13 to 15), the distal end pin 14 is screwed and held in the balance weight storage unit 24 in advance with the side of the pin 14 facing the balance weight mounting unit 7.

Further, a small-diameter attachment / detachment insertion hole 26 that opens toward the balance weight storage section 24 is formed in the inner peripheral wall 25 of the turbine casing 1 located near the rotor 3. The attachment / detachment insertion hole 26 faces the opening of the screw hole serving as the balance weight storage unit 24, and is a slanted hole having both ends opened coaxially on an extension of the axis of the hole. The attachment / detachment insertion hole 26 is
(See FIGS. 16 and 17) The diameter of the rod 17 is set so that the rod 17 can be inserted. The outer surface side has a screw hole, and a plug 27 for opening and closing the hole is detachably mounted on the screw hole portion. , During normal operation.

Next, the operation will be described.

When the work of mounting the balance weight 8 is performed, first, the plug 27 attached to the small-diameter attachment / detachment insertion hole 26 of the turbine casing 1 is removed. The rod 17 of the attachment / detachment tool 16 is inserted into the attachment / detachment insertion hole 26 thus opened from the tip end side into the turbine casing 1, and the projection 18 having a rectangular cross section projecting from the tip end of the rod 17 is attached to the balance weight storage unit 24. Is fitted into the concave portion 15 of the balance weight 8 which has been attached in advance, and in this state, it is rotated through the handle 19 of the attachment / detachment 16. Since the internal thread is formed in the balance weight storage section 24, the stored balance weight 8 advances from the balance weight storage section 24 toward the balance weight mounting section 7 of the rotor 3, and finally the rotor 3 It is attached to the balance weight attachment part 7.

In the work of attaching the balance weight, the work can be performed without breaking the vacuum in the turbine casing 1 during the work, so that a small amount of air flows through the small-diameter mounting / detaching tool insertion hole 26 provided in the turbine casing 1. Flows into the turbine casing 1, but since the attachment / detachment insertion hole 26 has a small diameter, the degree of vacuum in the turbine casing 1 is maintained by the vacuum pump of the condenser of the ordinary steam turbine.

As described above, according to the balance weight mounting apparatus of the first embodiment, the work of mounting the balance weight can be performed without the need to break the vacuum in the turbine casing 1, so that the vacuum break and the degree of vacuum increase can be performed. The balance weight 8 can be efficiently attached in a shorter time as compared with the prior art which involves the above operation.

Second Embodiment (FIGS. 2, 10, 13 to 13)
17) FIG. 2 is a sectional view showing the steam turbine balance weight mounting apparatus according to the present embodiment.

The configuration of this embodiment is different from that of the first embodiment in that a rising wall is not provided in the ground seal portion 22 and the balance weight storage portion 24 and the mounting / removing tool insertion hole 26 are connected to the cylinder 28.
In that they are connected to each other via the

That is, also in this embodiment, as shown in FIG. 2, a plurality of screw hole-shaped balance weight mounting portions 7 are provided at the downstream stage side end of the rotor 3 of the steam turbine low pressure portion.
Are provided at intervals along the circumferential direction in an arrangement inclined with respect to the axis of the rotor 3. The openings of the holes as the respective balance weight mounting portions 7 are set at the same distance from the rotor axis, and are inclined at the same angle from there toward the hole bottom.

The stationary portion close to the balance weight mounting portion 7, for example, the inner end side of the ground seal portion 22 provided with the labyrinth packing 21 and the like has a flat shape and has no rising wall. Therefore, a cylinder 28 through which the balance weight 8 can be inserted is integrally protruded from an inner peripheral wall 25 of the turbine casing 1 located near the rotor 3, and a balance weight storage unit 24 is provided at a tip of the cylinder 28. That is, the cylinder 28 is configured to include a screw hole serving as the balance weight mounting portion 24. The balance weight 8 (see FIG. 13 to FIG. 15) is screwed and held in advance in the balance weight storage unit 24 with the end pin 14 side facing the balance weight mounting part 7.

Further, a small-diameter attachment / detachment insertion hole 26 that opens toward the balance weight storage section 24 is formed in the inner peripheral wall 25 of the turbine casing 1 located near the rotor 3. The attachment / detachment insertion hole 26 is an inclined hole at both ends opened in a state where the attachment / detachment insertion hole 26 communicates coaxially with the cylinder 28 as the balance weight storage unit 24. This attachment / detachment tool insertion hole 2
6 is set to a diameter that allows the rod 17 of the attachment / detachment tool 16 (see FIGS. 16 and 17) to be inserted, and has a screw hole on the outer surface side, and a plug 27 for opening and closing the hole is provided in the screw hole portion. It is detachably mounted and is closed during normal operation.

Next, the operation will be described.

When the work of mounting the balance weight 8 is performed, also in this embodiment, first, the plug 27 attached to the small-diameter attachment / detachment insertion hole 26 of the turbine casing 1 is removed. The opening 26 for the attachment / detachment tool thus opened.
Then, the rod 17 of the attachment / detachment tool 16 is inserted from the distal end side into the cylinder 28 toward the turbine casing 1, and
A convex portion 18 having a rectangular cross section projecting from the tip of 7 is fitted into the concave portion 15 of the balance weight 8 previously attached to the balance weight storage portion 24, and in this state, is rotated via the handle 17 of the detachable tool 16. Since the internal thread is formed in the balance weight storage section 24, the stored balance weight 8 advances from the balance weight storage section 24 toward the balance weight mounting section 7 of the rotor 3, and finally the rotor 3 Balance weight mounting part 7
Attached to

In the work of attaching the balance weight, the work can be performed without breaking the vacuum in the turbine casing 1 during the work. Although some air flows into the turbine casing 1, the degree of vacuum in the turbine casing 1 is maintained by the vacuum pump of the condenser of the ordinary steam turbine because the attachment / detachment insertion hole 26 has a small diameter. .

As described above, according to the balance weight mounting apparatus of the second embodiment shown in FIG. 2, the work of mounting the balance weight can be performed without breaking the vacuum in the turbine casing 1. The balance weight 8 can be efficiently attached in a shorter time as compared with the prior art which involves an operation such as an increase in the degree.

Third Embodiment (FIGS. 3, 10, 13 to 13)
17) FIG. 3 is a sectional view showing a balance weight mounting device for a steam turbine according to the present embodiment.

The structure of the present embodiment is different from the above embodiments in that the ground seal portion 22 has a large thickness in the direction perpendicular to the rotor axis, and the balance weight storage portion 24 is attached to and detached from the ground seal portion 22. A hole 29 communicating with the tool insertion hole 26 is formed, and a screw hole serving as the balance weight attaching portion 7, the balance weight storage portion 24, the attachment / detachment insertion hole 26, and the axis of the hole 29 are aligned with the axis of the rotor. The point is that they are formed in parallel directions.

That is, also in this embodiment, as shown in FIG. 2, a plurality of threaded hole-shaped balance weight mounting portions 7 are provided at the downstream stage side end of the rotor 3 of the steam turbine low pressure portion. The screw hole-shaped balance weight mounting portion 7 is formed in a direction parallel to the axis of the rotor 3. The openings of the holes as the balance weight mounting portions 7 are respectively set at the same distance from the rotor axis.

The inner end side of the stationary portion close to the balance weight attaching portion 7, for example, the ground seal portion 22 provided with the labyrinth packing 21 and the like, is formed to be thicker than the above-mentioned embodiments. A hole 29 for passing the storage unit 24 and the attachment / detachment tool 16 is formed. Other configurations are substantially the same as those of the above embodiments except that the balance weight storage unit 24 and the attachment / detachment insertion hole 26 are parallel to the axis of the rotor 3, and thus the description thereof is omitted.

In this embodiment having such a structure,
When the work of attaching the balance weight 8 is performed, first, the plug 27 attached to the small-diameter attachment / detachment insertion hole 26 of the turbine casing 1 is removed. Thus, the rod 17 of the attachment / detachment 16 is inserted into the attachment / detachment insertion hole 26 opened from the tip side along the inner surface of the hole 29 toward the inside of the turbine casing 1, and the projection having a rectangular cross section protruding from the tip of the rod 17. The fitting 18 is fitted into the recess 15 of the balance weight 8 previously attached to the balance weight storage unit 24, and in this state, is rotated via the handle 19 of the attachment / detachment 16. Since the internal thread is formed in the balance weight storage section 24, the stored balance weight 8 advances from the balance weight storage section 24 toward the balance weight mounting section 7 of the rotor 3, and finally the rotor 3 It is attached to the balance weight attachment part 7.

In such a work for attaching the balance weight, since the work can be performed without breaking the vacuum in the turbine casing 1 during the work, the small-diameter hole 29 and the attachment / detachment insertion hole provided in the turbine casing 1 are provided. Although some air flows into the turbine casing 1 from 26,
Since these holes 29 and the attachment / detachment insertion holes 26 have small diameters, the degree of vacuum in the turbine casing 1 is maintained by the vacuum pump of the condenser of the ordinary steam turbine.

Therefore, even with the balance weight mounting apparatus of the third embodiment, the work of mounting the balance weight can be performed without the need to break the vacuum in the turbine casing 1, so that the work of breaking the vacuum and increasing the degree of vacuum can be performed. Compared with the related art, the balance weight 8 can be efficiently attached in a shorter time.

Fourth Embodiment (FIGS. 4 to 9 and FIG. 10) FIG. 4 is a sectional view showing a steam turbine balance weight mounting apparatus according to this embodiment. FIG. 5 is an enlarged front view showing the configuration of the balance weight 30 used in the present embodiment, FIG. 6 is a bottom view thereof (a view taken in the direction of arrow D in FIG. 5), and FIG. 5 as viewed from the direction of arrow E). FIG. 8 shows the balance weight 30 attached to the balance weight mounting portion 7.
FIG. 9 is a cross-sectional view showing a state where a plurality of balance weights 30 are stored in the balance weight storage unit 24. FIG.

The apparatus of this embodiment is similar to the second embodiment, except that the balance weight storage section 24 and the attachment / detachment insertion hole 2 are provided.
6 are connected to each other by a cylinder, and the point that the cylinder is a double cylinder and a plurality of balance weights 30
Are stored at the same time, and one balance weight 30 can be mounted using the balance weights 30.

That is, in this embodiment, as shown in FIG. 4, the balance weight storage section 24 and the attachment / detachment insertion hole 26 communicate with each other via a cylinder. The inner cylinder 32 inserted into the outer cylinder 31 so as to be slidable in the axial direction has a double structure. The outer cylinder 31 is inserted into a through hole 33 formed in the inner peripheral wall 25 of the casing 1, and a flange 34 provided at one end of the outer cylinder 31 is brought into contact with the outer surface of the inner peripheral wall 25 of the casing 1, and a bolt or the like is used. Are fixed by the fasteners 35.

The inner cylinder 32 also has a flange 36 on one end side of the cylinder main body 32a. The cylinder main body 32a is slidably inserted through the inner peripheral surface of the outer cylinder 31 and the flange 36 On the outer surface of the flange 34 of the outer cylinder 31,
It is fixed by a fastener 38 such as a bolt via a detachable spacer 37 in the form of a divided disk. For example, the spacer 37 has a shape in which a part of the entire circumference is cut away or the like so that the spacer 37 can be removed in a direction perpendicular to the axis with respect to the inner cylinder 32.

When the fastener 38 of the inner cylinder 32 is removed and the spacer 37 is separated and separated, the inner cylinder 32 can be inserted into the casing 1 by the interval set by the spacer 37. This insertion distance is equal to the inner cylinder 32.
Is set to such a degree that the inner end of the casing 1 contacts the surface of the rotor 3. In addition, a female screw is formed on the inner surface of the inner cylinder 32, and a plug 27 is mounted on a portion of the inner cylinder 32 facing the outside of the hole.

On the other hand, as shown in FIGS. 5 to 7, the balance weight 30 has a cylindrical body 39 having external threads on the outer peripheral surface.
A pin 40 having a circular cross section is provided on the tip side of the pin 40, and for example, a square convex portion 41 is formed at the root of the pin 40, and a square concave portion 42 having the same shape as the convex portion 41 is formed at the rear end of the body 39.
Is formed. As a result, the convex portions 4
By fitting the recess 1 into the recess 42, the plurality of balance weights 30 can be integrally rotated while being connected in the axial direction.

As shown in FIG. 9, a plurality of balance weights 30 are inserted into the inner cylinder 32 in advance so as to be integrally rotatable while being connected in the axial direction. Further, as shown in FIG. 9, the balance weight 30 is inserted into the screw hole serving as the balance weight attachment part 7 in a state in which the body 39, the protrusion 41, and the pin 40 are buried.
Other configurations are substantially the same as those in the second embodiment, and therefore, the same reference numerals as in FIG.

The operation of mounting the balance weight according to the fourth embodiment having the above configuration will be described below.

First, the plug 27 is removed, and the fastener 38 of the flange 36 fixing the inner cylinder 32 and the spacer 37 is removed.
The spacer 37 is removed from between 36. In this state, the inner cylinder 3
2 is pushed in the direction of the balance weight attaching portion 7 of the rotor 3 so that the inner cylinder 32 is slid within the outer cylinder 31 so that the inner end of the inner cylinder 31 on the inner side of the casing 1 approaches the balance weight attaching portion 7. Let it. Next, the aforementioned attachment / detachment tool 1
6 into the inner cylinder 32 and the balance weight storage unit 24
The rod 1 of the attachment / detachment tool 16 is inserted into the recess 42 of the outermost one 30a of the plurality of balance weights 30 stored in advance.
The rotation operation is performed by fitting the projections 18 having a rectangular cross section at the seven tips. When the outermost one 30a of the balance weights 30 is rotated, the balance weights 30 in front of the balance weights 30 are similarly rotated sequentially, and the plurality of balance weights 30 rotate and move forward.

Thus, the plurality of balance weights 30
The balance weight 30b at the foremost end is screwed into the balance weight mounting portion 7 of the rotor 3 and fixed. At this time, the convex portion 41 of another balance weight 30c adjacent to the balance weight 30b fixed to the balance weight attachment portion 7 of the rotor 3 is connected to the balance weight 30 inserted into the balance weight attachment portion 7.
B is fitted in the recess 42.

Therefore, without rotating the balance weight 30a in the balance weight storage section 24, the inner cylinder 32 is slid in the outer cylinder 31 and pulled up, so that the recess 15 of the balance weight 30b in the balance weight mounting section 7 is removed. Then, the convex portion 41 of the adjacent balance weight 30c is pulled out. As a result, only the balance weight 30b in the balance weight attaching section 7 remains in the balance weight attaching section 7.

On the other hand, the plurality of balance weights 30 left in the balance weight storage section 24 in the inner cylinder 32 are then rotated by the attachment / detachment tool 16, and the entirety of the balance weight 30c to be newly positioned at the front end is obtained. Is buried in the balance weight storage unit 24.

Thereafter, the attachment / detachment tool 16 used for rotating the balance weight 30 is removed from the inner cylinder 32, and the inner cylinder 3
The plug 27 is mounted on the inner cylinder 2 to close the hole of the inner cylinder 32. Thereafter, both fixing flanges 34 of the inner cylinder 32 and the outer cylinder 31 are provided.
The spacer 37 is inserted again between the spacers 36, and the fixing flange 36 of the inner cylinder 32 and the spacer 37 are fixed by the fastener 38 of the fixing flange 36 of the inner cylinder 32.

According to such a fourth embodiment, the inner cylinder 3
2 has a small diameter and the hole in the inner cylinder 32 is closed by a plurality of balance weights 30, so that the amount of air flowing into the casing 1 during the work of attaching the balance weight is small, and the vacuum in the casing 1 is reduced. There is no need to break, and the work of mounting the balance weight 30 can be performed while maintaining a high degree of vacuum.

In the present embodiment, since a plurality of balance weights 30 are stored in the balance weight storage unit 24, these balance weights 30 are stored in the balance weight storage unit 24.
With the intermittent rotation of the rotor 3, the balance weights 30 can be sequentially attached to the plurality of balance weight attachment portions 7 provided along the circumferential direction of the rotor 3, so that workability can be greatly improved. become.

Further, the balance weight 30 already attached to the balance weight attachment portion 7 of the rotor 3 is
Since it is possible to remove the balance weights in the reverse order to the above, it is possible to easily perform a complicated balance weight mounting work for mounting and removing a plurality of balance weights 30.

[0063]

As described above, according to the steam turbine balance weight mounting apparatus of the present invention, the balance weight can be relatively easily operated while maintaining the degree of vacuum in the turbine casing during the balance weight mounting operation. Can be efficiently performed, and the work of breaking the vacuum and raising the vacuum, which is conventionally required, is not required, and the effect of efficiently performing the balance weight mounting work in a shorter time is exhibited.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a balance weight mounting device for a steam turbine according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a balance weight mounting device for a steam turbine according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a balance weight mounting device for a steam turbine according to a third embodiment of the present invention.

FIG. 4 is a sectional view showing a balance weight mounting device for a steam turbine according to a fourth embodiment of the present invention.

FIG. 5 is an enlarged front view showing a configuration of a balance weight used in a fourth embodiment.

FIG. 6 is a view as seen in the direction of arrow D in FIG. 5;

FIG. 7 is a view as seen from an arrow E in FIG. 5;

FIG. 8 is a sectional view showing a state in which a balance weight is mounted on a balance weight mounting portion in the fourth embodiment.

FIG. 9 is a sectional view showing a state where a plurality of balance weights are stored in a balance weight storage unit in the fourth embodiment.

FIG. 10 is a cross-sectional view schematically showing a general configuration example of a low-pressure section of a steam turbine.

FIG. 11 is an enlarged cross-sectional view showing a structure near a balance weight mounting portion of a rotor in a turbine low-pressure section according to the related art.

FIG. 12 is a cross-sectional view showing a state where the balance weight is attached to the balance weight attachment section shown in FIG. 11 in a further enlarged manner.

FIG. 13 is an enlarged front view showing a general configuration of a balance weight.

FIG. 14 is a view as seen in the direction of arrow A in FIG. 13;

FIG. 15 is a view as seen in the direction of arrow B in FIG. 13;

FIG. 16 is a front view showing a configuration of a detachable tool for attaching and detaching a balance weight.

FIG. 17 is a view as seen in the direction of arrow C in FIG. 16;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Turbine casing (casing of low pressure part of steam turbine) 2 Moving blade 3 Rotor 4 Stator blade 5 Steam inlet 6 Low pressure casing outlet side exhaust port 7 Balance weight attaching part 8 Balance weight 9 Cone part 10 Manhole 11 Cover 12 Male screw part 13 Body 14 Pin 15 Concave part 16 Removable tool 17 Rod 18 Convex part 19 Handle 21 Labyrinth packing 22 Ground seal part 23 Rise wall 24 Balance weight storage part 25 Inner peripheral wall part 26 Removable tool insertion hole 27 Plug 28 Tube 29 hole 30 (30a, 30b, 30c) ) Balance weight 31 Outer cylinder 32 Inner cylinder 32a Cylinder main body 33 Through hole 34 Flange 35 Fastener 36 Flange 37 Spacer 38 Fastener 39 Body 40 Pin 41 Convex part 42 Concave part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16F 15/34 F16F 15/32 E

Claims (4)

[Claims] 1. A plurality of balance weight attachment portions are provided at intervals in a circumferential direction at an end of a downstream stage side of a rotor of a steam turbine low pressure portion, and these balance weight attachment portions are selectively provided for stabilizing rotor rotation. In a steam turbine balance weight mounting device in which a balance weight is removably mounted, a balance weight storage section is provided in a stationary portion near the balance weight mounting section, and the balance weight is removably stored therein. A steam turbine, wherein a small-diameter attachment / detachment insertion hole that opens toward the balance weight storage section is formed in a wall of a turbine casing, and an opening / closing plug is detachably provided in the attachment / detachment insertion hole. Balance weight mounting device. 2. The balance weight mounting device for a steam turbine according to claim 1, wherein the balance weight is configured to be screwed into the balance weight mounting portion, and the balance weight mounting portion, the balance weight storage portion and A balance weight mounting device for a steam turbine, wherein the attachment / detachment mounting holes are arranged on the same axis. 3. The steam turbine balance weight mounting device according to claim 1, wherein the balance weight storage unit and the attachment / detachment insertion hole communicate with each other via a hole or a cylinder. Turbine balance weight mounting device. 4. The steam turbine balance weight mounting device according to claim 3, wherein the balance weight storage section and the attachment / detachment insertion hole communicate with each other via a cylinder, wherein the cylinder is fixed outside the fixed state. While the cylinder and the inner cylinder inserted in the outer cylinder so as to be slidable in the axial direction have a double structure, the balance weight has a square convex portion at the front end and a square concave portion at the rear end. A balance weight for the steam turbine, wherein a plurality of the protrusions and the recesses are fitted to each other to be axially connected to each other and inserted into the inner cylinder so as to be integrally rotatable. Mounting device.