JPS58150004A - Cooling structure for moving blade implantation part - Google Patents

Abstract

PURPOSE:To ease manufacture and assembly of each component of an implantation part cooling structure by providing a groove at the bottom of a serration installed in a disc for insertion of the implantation part of a moving blade and inserting into said groove a fixing pin of a cooling air leakage preventive plate for the implantation part. CONSTITUTION:A groove 9 is formed at the bottom of a serration 5 in a disc 2 and an implantation part 4 for a Christmas tree-shaped moving blade is inserted in the serration 5, and the moving blade 3 is fitted to said implantation part 4. Cooling air leakage preventive plates 10 for the implantation part are brought into contact with a lateral face of the gas intake port side and the same of the gas outlet port side of the disc 2 and the moving blade implantation part 4 respectively, and further a fixing pin 11 is provided piercing through plates 10 and the groove 9. The plural number of notches 12 providing the route between the groove 9 and the serration 5 are formed in the middle part of the pin 11, which is supported by means of dropping preventive pins 13 installed on both end parts of the groove 9. Further, the disc 2 is provided with an inflow passage 23 communicating with the groove 9 and feeding cooled air.

Description

[Detailed description of the invention] Technical field of invention The present invention provides a rotor blade embedded cooling structure K11l.

Generally, in gas turbines, steam turbines, etc., a large number of rotor blades are installed by implanting the rotor blades into the disk of the rotor. Today, the rotor blade implant is shaped like a Christmas tree. When the turbine is in operation, the rotor blade installation part is heated and a large thermal stress is generated, so cooling air is supplied to the rotor blade installation part t to cool it.

The rotor blade implant cooling structure attempts to effectively cool the rotor blade implant.

Technical background of the invention and its problems As shown in FIG. 1, a large number of rotor blades 3 are attached to the outer periphery of a disk 2 of a rotor 1 of a turbine. Each rotor blade 3 has a Christmas tree-shaped rotor blade implantation portion 4 at its root, and this Christmas tree-shaped rotor blade implantation portion 4 is fitted into a celery seal 5 carved on the disk 2. It is installed by

As shown in the plan view of Fig. 2, conventionally the serration 1 is carved parallel to the axis 1a of the rotor 1, and the Christmas tree-shaped rotor blade implantation part 4 is fitted parallel to the axis 1m. Was.

However, as the scale of power generation plants and the like has increased in recent years, the parts where the rotor blades are installed are subjected to large centrifugal forces and exposed to high temperatures during turbine operation, resulting in large stresses being generated.

Therefore, in order to reduce the stress that occurs in the rotor blade implantation part,
As shown in FIG.
The Christmas tree-shaped rotor blade embedding part 4v formed so as to match this ceresai mark 5 is installed and tilted at an angle of about 15 degrees from the rotor blade 31' axis. It is proposed to install.

However, when the rotor blade is tilted 1 m from the axis of the 3Y rotor, it is difficult to manufacture and assemble a cooling structure for cooling the rotor blade, and there are other inconveniences such as poor cooling efficiency. there were.

To explain further, when the rotor blades 3 are installed parallel to the 1 m axis of the rotor 1 as shown in Fig. 2, the cooling air leak prevention plate 5 of the rotor blade embedded cooling structure is installed as shown in Fig. 3. ) 6Y Christmas tree type rotor blade embedded part 4 can be firmly fixed by a fixing pin 7 passed through in parallel with the axis 1 m.

However, as shown in FIG.
Even when the bucket is tilted as shown in FIG.
The drilling work is troublesome because it is necessary to drill an 8V diagonal through hole to the pipe, and the cooling air leakage prevention play) 8V fixing pin 7 is used to tighten from a direction inclined to the fixing surface. Therefore, compared to the case shown in Fig. 3, the tightening force is smaller. If this tightening force is small, it will not be possible to support the weight of the rotor blade 30 acting on the fixing bin 7 when the turbine operation is stopped. In order to sufficiently support the weight of the rotor blade 30, K must increase the tightening force of the fixing bin 7, but as mentioned above, since the fixing bin 7 is installed at an angle, the tightening force must be increased. In addition, if the tightening force by the fixing pin 7 is insufficient, the air leakage prevention plate 6 will move in the radial direction and will be fed to the rotor blade installation part. There is a risk that the cooled air may leak outside.

OBJECTS OF THE INVENTION The present invention has been made in view of the problems of the background art described above, and it is easy to manufacture and assemble each component of the rotor blade implant cooling structure, and the rotor blade implant is parallel to the axis of the rotor. Even if the blade is tilted or tilted, it can always be held in the proper position, reducing the amount of cooling air leaking from the rotor blade implant. An object of the present invention is to provide a cooling structure for a rotor blade embedded part that can effectively cool a rotor blade embedded part.
The mobilization part of the disk is fitted with a Christmas tree-like rotor blade implant, and one side or both sides 11 of the disk and the Christmas tree-type rotor blade implant on the gas inlet side or outlet side. A groove is formed between the abutted implant cooling air leakage prevention plate and the groove that is penetrated through the implantation cooling air leakage prevention plate and is continuous with the lower part of the serration ring of the disk. and a fixing bottle provided in the groove and tightly fixing the implant cooling air leak prevention plate to the disk, and a fixing bottle provided in the groove to fix the fixing bottle radially inward. A fall prevention key that is supported at 5 so that it cannot be moved, and a cooling air flow path that communicates with the outside through a cooling air leakage prevention plate from the inside of the rotor blade through the embedded part of the rotor blade. The groove forming the upstream side of the cooling air flow path, the serration portion forming the downstream side, and the notch k formed in the fixing bottle are formed so as to communicate with each other.

In the present invention, a groove is formed in the disk to allow the fixing pin to pass through, and this groove is separated from the serrations and closed to allow the fixing pin to be attached. It is easier to process than those in which a through hole is provided in the implanted part. This is particularly advantageous when the rotor blades are installed at an angle with respect to the axis of the rotor.

In addition, the fall prevention key prevents the fixing bolt from moving in the radial direction even when the rotor stops rotating, so it can be kept in the proper position (to prevent cooling air from leaking into the implanted area). The leakage of cooling air can be reduced to an extremely small amount, resulting in high cooling efficiency.

Further, since a notch is provided in the fixing pin to communicate with the groove and the serration portion, cooling air can flow smoothly and cooling efficiency can be increased.

Examples of the invention 6-7 show an embodiment of the present invention.

As shown in FIG.
A groove 9 is provided parallel to the . The rotor blade 3 is attached by fitting the Christmas tree-shaped rotor blade mounting portion 4 into the serrations 5. The gas inlet side side surface (left side surface in FIG. 6) and the gas outlet side 1-side (right side in FIG. 6) K of the disc 2 and the rotor blade implanted portion 4 are plates 10 for preventing leakage of cooling air in the implanted portion, respectively. .10 are in contact with each other. A fixing ring 11 having a circular cross section is attached to the implant cooling air 1 leak prevention plate 10 and the groove 9 of the disk 2.
By tightening this fixing pin, the plate 10 is firmly attached to the disk 2 and the rotor blade implantation portion.

This fixing pin 11 is formed to have the same width and outer diameter as the groove 9, and is designed to separate and close the groove 9 and the serrations 5.
C and penetrated (see @Figure 7).

The fixing pin 11 has a groove 9 and a serration 5 in the middle! A plurality of cutouts 12 are provided that communicate with each other. Further, the fixing pin 11 is supported by fall prevention pins 13 provided at both ends of the groove 9, and is fixed so as not to move inward in the radial direction even when the rotor is stopped. plate 1
0 engages with a jaw 14 provided on the disk 2 to support the centrifugal force during rotation, and engages with another jaw 15 to absorb bending stress caused by tightening the fixing pin 11. It is designed to receive.

Further, an inflow channel is provided in the disk 2 that communicates with the groove 9 and supplies cooling air. As shown in FIG. 7, a gap 16 through which cooling air can flow is formed in the axial direction between the serrations 5 and the Christmas tree-shaped rotor blade embedded portion 4. As shown in FIG. Furthermore, an upstream air chamber 17 is formed between the plate 10 on the gas inlet side and the rotor blade embedded part 4, and an upstream air chamber 17 is formed between the plate 10 on the gas outlet side and the rotor blade embedded part 4. A downstream air chamber 18 is formed. Further, a gas outlet 19 is provided on the grate 10 on the gas outlet side. Furthermore, each plate 10 has a main gas 'R, lI! in combination with a fin (not shown) on the nozzle diaphragm side. Fins 4 are formed to protrude in the axial direction to create a pressure difference between 120 and the cooling air flow side 4.

Next, the operation of this embodiment will be explained.

The rotor 1v is rotated to feed cooling air into the inflow path n of the disk 2.

At this time, the cooling air flows into the groove 9 through the inflow path S,
It flows into the serrations 5 through the notches 12 and 12t', then flows into the upstream air chamber 17, and then passes through each gap 16 of the serration section into the lower + 1) IEIII air chamber 1.
8 and flows out through the gas outlet 19 to the outside.

In this way, the rotor blade implant is effectively cooled as the cooling air flows through the disk 2 and the cooling air flow path in the rotor blade implant. In addition, cooling air fM passes through the gas outlet 19,
The cooling gas that has flowed out to the 21 is transferred to the main gas f! It flows into the L111 chamber through the fins and merges with the main gas flow. Since the play plate 10 is held at a proper position, the fin ρ rotates at a constant position, and the cooling air fL114 is always kept at a high pressure with respect to the main gas flow side 20.

Therefore, the cooling effect of the cooling air is increased. In addition, the inflow of cooling air from the groove 9 to the serration 5 is also carried out through the notch 1.
2'lk: The air flow is carried out smoothly without large pressure loss, and the rotor blade implantation part is effectively cooled by a large amount of cooling air.

In addition, when the rotor is stopped, the fixing bin 11
The fall prevention key 13 prevents the slider from moving inward in the radial direction. Therefore, the amount of leakage of cooling air is also minimized, and the cooling effect is increased. Further, as shown in FIG. 7, the fixing bin 11 comes into contact with the lower surface of the rotor blade mounting portion 4 when the rotor blade is stopped, thereby supporting the rotor blade 3.

In this case as well, the locking bottle 1 is
1 is immovably supported. From these descriptions, it can be seen that the plate 10 is fixed to the disk 2 etc. in an immovable state S both when the rotor is rotating and when it is stopped.

Therefore, the amount of leakage of cooling air is reduced, and cooling efficiency is improved.

It can also be seen from these that it is not necessary to tighten the fixing bolts with an unnecessarily large tightening force in order to fix the plate χ in an immovable state. Therefore, even if the plate is installed at an angle to the axis of the rotor, which is a moving blade, It can be immovably mounted on a disk, etc.

Note that the plate 10 can also be provided only on either the gas inlet side or the gas outlet side.

Further, with the above configuration, the rotor blades can be mounted parallel to the axis of the rotor.

Effects of the Invention Fifth, the rotor blade embedded cooling structure of the present invention has a simple structure and is easy to assemble, and the embedded cooling air leakage prevention plate remains stationary even when the rotor is rotating and when the rotor is stopped. The system can be supported by holding it in place, minimizing the amount of cooling air leakage, improving cooling efficiency, and the notch provided in the fixing bin allows for smooth circulation of cooling air within the flow path. The cooling efficiency is also improved, and even if one blade is attached to the rotor at an angle and in parallel with the axial direction, the cooling efficiency can be maintained at a high level, which has the effect of increasing the operating capacity of the turbine.

[Brief explanation of drawings]

Fig. 1 is an end-to-end view showing the rotor blade embedded part, Fig. 2 is a plan view of Fig. 3, Fig. 3 is an enlarged sectional view taken along the line ■-■ in Fig. 1,
Figure 4 shows the second rotor blade tilted relative to the rotor axis.
FIG. 5 is a sectional view similar to FIG. 3 showing another example of the rotor blade implantation part, FIGS. 6 and 7 show an embodiment of the present invention, and FIG. 6 is the same as FIG. An enlarged cross-sectional view along the vt-vt line of
FIG. 7 is an enlarged sectional view taken along the line ■--■ in FIG. 1... Rotor, 2... Disc, 3... Moving blade, 4
···Chris! Tree-type rotor blade embedded part, Serration, 9... Groove, 10... Plate for preventing leakage of cooling air in the embedded part, 11... Fixing bin, 12... Notch, 13 ...Fall prevention key O Applicant: Director of the Agency of Industrial Science and Technology Ishizaka Tsutomu - 1st prisoner - 2nd eye Kaya 3 Figure 5th eye 6th eye

Claims (1)

[Claims] A rotor disk, a rotor blade fitted with a Christmas tree-shaped blade insert into the serration ring of the disk, and gas inlet and outlet sides of the disk and Christmas tree-type rotor blade insert. An implant cooling air leakage prevention plate that is in contact with one or both sides, and a plate that is penetrated by the implant cooling air leakage prevention plate and is formed continuously at the lower part of the serration eye of the disk. a fixing pin provided in the groove to separate and close the groove and the ceresus plate, and for tightly fixing the plate for preventing leakage of implanted cooling air to the disk; The fixing pin cannot be moved radially inward.
CL, a key to prevent falling, and a plate to prevent cooling air from leaking through the rotor blade implantation area from inside the recording disk)
A cooling air flow path that communicates with the outside! The groove forming the upstream side of the cooling air flow path and the serration seal portion forming the downstream side are communicated with each other through a notch formed in the fixing hole. Wing implant cooling structure.