JP3524765B2 - Turbine blades - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbine rotor blade, and more specifically, a plurality of rotor blades are planted in a circumferential groove formed on the outer periphery of a rotor and fixed to the rotor by a disk pin. Type of steam turbine rotor blade.

[0002]

2. Description of the Related Art A steam turbine, which expands high-pressure steam to convert the heat energy of the steam into mechanical work, is capable of producing large horsepower and high-speed rotation. Therefore, it is widely used for power generation or for driving a compressor of a chemical plant. It is used.

Turbines can be classified into several types according to the operating mode of steam power, the flow direction of steam, and the like. Regardless of the type of turbine, high-pressure, high-temperature steam generated in a boiler is used. Is a unit of a set of paragraphs composed of a stationary blade (or a nozzle) for ejecting the water vapor and a moving blade having a vane-shaped cross-sectional profile for generating a rotational force by receiving the steam jet having the velocity energy.

Since the rotor blade is attached to the rotor rotating at a high speed, it receives centrifugal force, vibrational stress, and bending stress. Therefore, the blade root portion, which is a portion where the rotor blade is attached to the rotor, is a joint that can withstand large stress. A method is required.

Therefore, in the conventional turbine, as shown in FIG. 7, a rotor disk 3 formed on the outer periphery of the rotor is used.
A peripheral groove 4 having an arbitrary cross-sectional shape (for example, an inverted T shape) is formed on the outer periphery of the blade root 5a having the same cross-sectional shape as the peripheral groove 4.
By loading the above, a large number of moving blades 1 were arranged and planted around the entire circumference of the rotor disk 3. Further, each moving blade 1 was sequentially loaded into the circumferential groove 4 from the filling hole 6 formed at one location of the circumferential groove 4, and moved in the circumferential direction to be fixed at a predetermined position.

Further, the moving blades 1a, 1 located at the position of the filling hole 6
In order to prevent jumping out due to a large centrifugal force generated during rotation, b is placed so as to hang over the filling hole 6 in half pitches as shown in FIG. 8, and is fixed to the rotor disk 3 by a disk pin 7a. At this time, the moving blade 1 at the position of the filling hole 6
Protrusion 8 as an engaging portion on the side opposite to the disk pin of a and 1b
a and 8b are provided, and the protrusions 8a and 8b are adjacent to the moving blade 1
The concave portions 9a and 9b as the engaging portions formed in c and 1d are engaged and fixed.

As described above, a required number of moving blades 1 are provided from the filling hole 6.
Blades 1 located in the filling holes 6 after charging the
Since it is necessary to shift a and 1b by half pitch, the blade root pitch of the entire circumference is adjusted to positively form the space 12 in the circumferential direction required for moving the rotor blade by half pitch.
After the loading operation of the moving blade 1 is completed, the tension key 13 is fitted into the space 12 as shown in FIGS.
It was fixed by crimping the top of a. Further, when the above-mentioned caulking work is completed, as shown in FIGS. 8 and 10, the shroud cover 15 is caulked and fixed to the tip of the moving blade 1 with the tenon 16, so that the moving blades 1 are separated one by one. Together, they prevented the vibration of the moving blades alone, and also prevented steam from leaking from the tip.

[0008]

However, the above-mentioned conventional turbine rotor blade has the following problems. That is, in a conventional turbine moving blade, a specially-shaped blade root is required at the position of the filling hole 6, and a tension key or the like is also required to fit it in the space. Therefore, the cost required for processing / assembly is required. Has risen.

Further, when it is desired to adopt the ISB structure (infinitely stapling structure with an integral shroud cover), the tension key causes a gap in the shroud cover, and the infinitely stapling wing structure can be adopted as it is. There wasn't.

The object of the present invention is to solve the above-mentioned conventional problems, and it is possible to fix the final implanting moving blade to the rotor by the disc pin as it is at the position where the final implanting blade is inserted into the filling hole. It is to provide such a moving blade of a turbine.

[0011]

The present invention is a moving blade of a turbine, which is configured as follows in order to solve the above-mentioned technical problems. That is, the rotor blade of the turbine of the present invention has a rotor supported in the turbine casing, a circumferential groove formed on the outer periphery of the rotor, and a plurality of holes sequentially implanted through the filling hole formed in the circumferential groove. Of the plurality of moving blades, and a stationary blade arranged in the vicinity of the moving blade, and receiving a high-speed steam flow blown from the stationary blade to relatively rotate the rotor. The moving blades on both sides of the moving blade are formed with an engaging portion with a blade pin that interlocks with a disk pin that fixes the final moving blade, and the final moving blade is inserted into the filling hole. It is characterized in that it is formed so as to be fixed to the rotor by a disc pin at a position.

The rotor includes a disk formed on the rotor. Further, this disk is manufactured as a one-piece structure carved from a forged steel ingot, or a disk separate from the rotor is manufactured. It includes a prefabricated type in which the disc is assembled into the rotor by shrink fitting.

The groove formed on the outer periphery of the rotor may have a cross-sectional shape other than the above-mentioned inverted T-shape, such as a two-step T-shape and an inverted Christmas tree shape. In this case, it goes without saying that it is necessary to match the shape of the blade root with the groove shape. Further, it is preferable to use a cam for the blade pin that interlocks with the disc pin.

The moving blade of the turbine of the present invention is composed of the above-mentioned essential constituent elements, and the constituent elements are realized even in the following specific cases. That is, as in the second aspect of the present invention, the final implanting blade is provided with a disk pin loading hole and a pair of blade pin loading holes that intersect and open with the disk pin loading hole. , Each blade pin charging hole has a built-in blade pin, and the moving blades on both sides of the final implanting blade are provided with engaging portions facing the final implanting blade. The portion may be engageable with a blade pin that is pushed forward by a disc pin that advances in the disc pin insertion hole when the final implanting blade is fixed at the loading position of the rotor. it can.

The angle at which the disk pin insertion hole intersects the blade pin insertion hole is preferably 90 degrees. However, it goes without saying that this can be set to an appropriate angle such as 45 degrees. Further, the engaging portions formed on the adjoining rotor blades facing the final implanting rotor blade may have a hole or groove shape.

Further, the blade pin incorporated in the blade pin insertion hole of the final implanting blade has its rear end portion exposed to the disk pin insertion hole, and at the same time, the blade pins are closely contacted with each other. It is preferable to leave it.

Further, it is preferable that when the tip of the disk pin and the rear end of the blade pin come into contact with each other, a smooth cam action is performed. It is preferable to provide a cam portion having an appropriate shape at the tip of the disk pin or the rear end of the blade pin. Further, in the turbine moving blade of the present invention, as in the invention described in claim 3, the engaging portions formed on the moving blades on both sides of the final implanting moving blade are holes, and It is characterized by having a depth that satisfies the formula. d = D / 2 + ε, where d: depth of holes provided on both adjacent moving blades, D: diameter of disk pin, and ε≈D / 2 * 0.1 to 0.3.

[0018]

According to the turbine blade of the invention described in claim 1, a required number of blades are inserted into the circumferential groove from the filling hole of the rotor disk, sequentially moved in the circumferential groove, and moved to a predetermined position. Place the wings. Before loading the final implanting blade from the filling hole, insert the blades on both sides. Finally, the final implanting blade is inserted through the filling hole, and then the disc pin is implanted in the rotor at that position. At that time, the disk pin and the blade pin are interlocked with each other to engage the blade pin with the moving blades on both sides.

Further, according to the turbine blade of the invention as set forth in claim 2, when the final implanting blade is fixed at the insertion position, the disk pin presses the blade pin built in the final implanting blade. To do. Then, the pushed blade pin advances into and engages with the engaging portions provided on both adjacent moving blades, and the final implanting moving blade and both adjacent moving blades are firmly held by the rotor disk.

According to the turbine rotor blade of the present invention as defined in claim 3, when fixing the final implanting rotor blade at the insertion position, the holes as the engaging portions provided in the rotor blades on both sides are slightly formed. There is a sufficient margin, and the blades on both sides are reliably fixed by the blade pins. Further, during rotation of the moving blade, the blade pin does not loosely move in the blade pin insertion hole and adversely affect the turbine.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the turbine rotor blade of the present invention shown in the drawings will be described below in more detail.
However, unless otherwise specified, the dimensions, materials, shapes, and relative arrangements of the components described in this embodiment are not intended to limit the scope of the present invention thereto, It is just an example of explanation.

FIG. 1 is a partially developed view of a rotor disk according to an embodiment of the present invention, showing a state before a rotor blade is planted in a circumferential groove formed in the circumferential direction. FIG. 2 shows a schematic cross-section of a rotor blade planted on a rotor disk along a circumferential groove. FIG. 3 shows a cross section taken along the line III-III in FIG. FIG. 4 is a cross section of the rotor blade taken along line IV-IV in FIG.
FIG. 5 is a cross section of the rotor blade taken along the line VV of FIG. FIG. 6 is a sectional view taken along the line VI-VI of FIG. 2 and shows the details of the mutual positional relationship between the disk pin and the blade pin.

The rotor disk 3 is provided with a groove 4 (see FIG. 1) having a substantially inverted T-shaped cross section on the outer periphery thereof. In addition, the filling hole 6 is formed at one place of the circumferential groove 4, and
Rims 17a and 17b are formed on both sides of the circumferential groove 4.

As shown in FIG. 2, the rotor blade 1 is provided with a blade root 5 having a substantially inverted T-shaped cross section which matches the cross sectional shape of the groove in the circumferential groove 4.
Are sequentially loaded into the circumferential groove 4 from the filling hole 6 and further moved in the circumferential direction so as to dispose the moving blade 1 at a predetermined position over the entire circumference of the rotor disk 3. The final implanting blade 10 inserted into the circumferential groove 4 from the filling hole 6 is fixed to the rotor 2 with the disk pin 7 at the insertion position. In the figure, the solid line shows the state after the disk pin 7 is driven. In addition, in this Embodiment, the last implantation blade 10,
All the moving blades including the moving blades 101 and 102 on both sides are provided with two grooves 18a and 18b.
The a and 18b are fitted to the rims 17a and 17b formed on the rotor disc 3 so as to prevent the circumferential groove 4 from being opened during rotation (see FIGS. 4 and 5). ).

A disk pin insertion hole 22 as shown in FIG. 6 is formed in the final implanting blade 10, and a blade pin insertion hole 23 opened from the left and right of the disk pin insertion hole 22.
a, 23b are bored, and further blade pins 24a, 24b are inserted into the blade pin insertion holes 23a, 23b, so that the blade pins 24a, 2b are attached to the final implanting blade 10.
The surface 4b is built in. Also, the moving blades 10 on both sides
On the side facing the final implanting blade 10 of Nos. 1 and 102, holes 25 as engaging portions for the blade pin insertion holes 23a and 23b.
a and 25b communicate with each other.

As shown in FIG. 6, the tip 71 of the disk pin 7 has a conical shape. Further, the blade pin 24a built in the blade pin insertion holes 23a, 23b,
24b has inner ends 26, 26 protruding into the disc pin insertion hole 22 and a tip 71 of the disc pin 7.
It is chamfered with the same conical surface as the conical surface of.

Further, a shroud cover 15 is fixed to the tip of the moving blade 1 by crimping with a tenon 16, so that several moving blades 1 are grouped together. For this reason, the rotor blade is prevented from vibrating independently and steam is prevented from leaking from the tip of the rotor blade.

In this embodiment, holes 25a and 25b as engaging portions formed in the moving blades 101 and 102 on both sides of the final implanting moving blade 10 are formed, and the depth of each hole is set to d.
= D / 2 + ε. In this case, d: the depth of the holes provided on the adjoining rotor blades, D: the diameter of the disk pin, ε≈D
/2*0.1 to 0.3, which is formed slightly deeper than the distance that the blade pins 24a and 24b are pressed and moved by the disk pin 7.

Next, in order to assemble the moving blades of the turbine according to the embodiment of the present invention, first, the required number of moving blades 1 are inserted into the circumferential groove 4 from the filling hole 6 of the rotor disk 3, and the circumferential groove 4 is sequentially inserted. The inside is moved, and the moving blade 1 is arranged at a predetermined position. After loading the moving blades 101 and 102 on both sides, the final implanting moving blade 10 is loaded from the filling hole 6. After the final implanting blade 10 is loaded through the filling hole 6, the disk pin 7 is driven in the direction indicated by the arrow A in FIG. 6 at that position to advance into the disk pin loading hole 22 for final implanting. Rotor disk 3 with rotor blade 10
Fixed to.

At this time, the conical surface formed at the tip 71 of the disk pin 7 becomes the conical chamfered portion of the inner ends 26, 26 of the blade pins 24a, 24b incorporated in the final implanting blade 10. Contact these blade pins 24a, 2
Press 4b. Then, the blade pins 24a, 24b
Moves into holes 25a and 25b as engaging portions provided in the moving blades 101 and 102 on both sides, and the final implanted moving blade 1
0 and the rotor blades 101 and 102 on both sides are held by the rotor disk 3. After the driving operation is completed, the disk pin 7 is fixed to the rotor disk 3 by caulking after cutting off the conical portion of the tip 71. Next, the shroud cover 15 is caulked and fixed to the tip of the moving blade 5 with the tenon 16, and the assembly work of the moving blade is completed.

According to the embodiment of the present invention, the plurality of moving blades 1 are loaded into the circumferential groove 4 from the filling hole 6 and sequentially moved to be arranged at a predetermined position of the rotor 2 (or the rotor disc 3). , Finally, at the position where the final implanting blade is inserted, the disk pin can be immediately driven without moving the final implanting blade, so that the rotor can be fixed to the rotor together with the adjacent blades. Moreover, the strength against centrifugal force can be improved as compared with the case of fixing only by the disk pin.

Further, after the moving blade is arranged at a predetermined position, the moving blade can be firmly fixed without using the tension key, so that the tension key and the tension key insertion work are eliminated, and the assembling work is simplified. As a result, the assembly time is greatly reduced.
In addition, an infinitely stapling blade structure (ISB) with an integrated shroud
A structure can be adopted. Further, since it is not necessary to manufacture many moving blades having a complicated special shape, and only a moving blade having a simple structure is required, the manufacturing cost of the moving blade is low.

Further, the holes 25a and 25b as engaging portions formed in the rotor blades on both sides of the final implanting rotor blade have a depth of d = D / 2 + ε (where d: both sides). Depth of the hole provided in the rotor blade, D: Diameter of disk pin, ε
.Apprxeq.D / 2 * 0.1 to 0.3), the distance is slightly deeper than the distance pressed by the disk pin, and there is a slight margin in the hole as the engaging portion provided in the moving blades on both sides. Therefore, the blades on both sides are reliably fixed by the blade pins.
In addition, the blade pin does not inadvertently move while the moving blade is rotating.

[0034]

As described above, according to the moving blade of the turbine of the present invention, a) a specially-shaped moving blade having a narrow blade root and a tension key are not required, and the turbine structure is simple. Therefore, the cost is reduced. b) At the position where the final implanting blade is inserted into the filling hole, the blade can be immediately fixed to the rotor without the work of shifting by a half pitch as in the conventional case, so that the assembly of the blade is extremely simple.

C) If the final implanting blade is fixed to the rotor with the disk pin, the blade pin moves to the engaging portion of the blades on both sides and is fixed in conjunction with the disk pin, so that a strong fixing is achieved. The centrifugal resistance strength is improved. d) Since the tension key is not required, the ISB structure (infinite spelling structure with an integral shroud cover) can be adopted.

E) The depth of each of the holes as the engaging portion is set to d = D / 2 + ε (where d is the depth of the holes provided on the adjoining rotor blades, and D is the diameter of the disk pin). , Ε≈D /
2 * 0.1-0.3), so not only is the blade pin fixedly secured on both sides of the moving blade, but it will not inadvertently move while the moving blade is rotating.

[Brief description of drawings]

FIG. 1 is a partially developed view of a rotor disk according to an embodiment of the present invention, showing a state before implanting a moving blade in a circumferential groove formed in a circumferential direction.

FIG. 2 is a schematic cross-sectional view showing a moving blade planted in the rotor disk shown in FIG. 1 cut along a circumferential groove.

FIG. 3 is a sectional view taken along line III-III in FIG.

4 is a cross-sectional view of the rotor blade taken along line IV-IV in FIG.

5 is a cross-sectional view of the rotor blade taken along the line VV of FIG.

6 is a cross-sectional view taken along the line VI-VI of FIG. 2 and shows the details of the positional relationship between the disk pin and the blade pin.

FIG. 7 is a partial development view of a rotor disk of a conventional turbine rotor blade, showing a state before the rotor blade is planted in a circumferential groove formed in a circumferential direction.

8 is a cross-sectional view showing a moving blade planted in the rotor disc shown in FIG. 7 along a circumferential groove.

9 is a sectional view taken along line IX-IX in FIG.

10 is a cross-sectional view taken along line XX of FIG.

[Explanation of symbols] 1 moving blade 2 rotors 3 rotor discs 4 circumferential groove 6 filling holes 7 disk pins 10 Final Implanting Blade 11 turbine cabin 21 static wings 22 Disc pin insertion hole 23 (23a, 23b) Blade pin insertion hole 24 (24a, 24b) Blade pin 25 Engagement part (hole as an engagement part) 101 Moving blades on both sides 102 Moving blades on both sides

─────────────────────────────────────────────────── ───Continued from the front page (56) Reference JP-A-8-260902 (JP, A) Actually opened 54-25901 (JP, U) Actually opened 63-119801 (JP, U) Actually opened 57- 198301 (JP, U) Actual development Sho 60-102402 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F01D 5/00-5/32

Claims (3)

(57) [Claims] 1. A rotor supported in a turbine casing,
A rotor provided with a peripheral groove formed on the outer periphery of the rotor, a plurality of moving blades sequentially implanted through the filling holes formed in the peripheral groove, and a stationary blade arranged in the vicinity of the moving blade, In a turbine that relatively rotates a rotor in response to a high-speed steam flow blown out from a stationary blade, in the moving blades on both sides of the final implanting moving blade of the plurality of moving blades,
The final implanting blade is formed so that it can be fixed to the rotor by the disc pin at the position inserted in the filling hole. Turbine rotor blades characterized by being 2. The final implanting blade is provided with a disk pin loading hole and a pair of blade pin loading holes that intersect the disk pin loading hole and open. A blade pin is built in, and the moving blades on both sides of the final implanting blade are provided with an engaging portion facing the final implanting blade, and the engaging portion includes the final implanting blade. When the rotor blade is fixed at the position where the rotor is loaded, it is formed so as to be engageable with a blade pin that is pushed forward by the disk pin that advances in the disk pin insertion hole. The moving blade of the turbine according to claim 1. 3. The engaging portion formed on the rotor blades on both sides of the final implanting rotor blade is a hole, and has a depth satisfying the following expression: 2. A moving blade of a turbine according to 2. d = D / 2 + ε However, d: depth of the holes provided in the moving blades on both sides D: diameter of the disk pin ε≈D / 2 * 0.1 to 0.3