JP2000274201A - Turbine rotor blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable safe operation by forming a blade planting part into a curved surface projected towards the circumferential direction of a turbine disk in the case of using a long blade for the final stage of a low-pressure turbine, so as to satisfy the increase of the output per unit machine of a steam turbine and the shortening of the whole length span at the same time. SOLUTION: A turbine rotor blade, having a blade length of 40 inch or more, is provided with a blade effective part 5 for making the steam work practically or changing a flow of the steam, a snapper cover 7 integrally scraped from a blade tip part 6, and a blade planting part 10 planted in a ring along the circumferential direction of a turbine disk 8 and integrally bonded to a blade root part 9 of the blade effective part 5. The blade planting part 10 is formed into a curve-entry christmas, while being formed into a curved surface projected toward the circumferential direction of the turbine disk 8, and the blade planting part 10 of the curve-entry christmas is fitted in a planting groove 15 provided in the turbine disk 8 so as to secure safe operation.

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 applied to the final stage of a low-pressure turbine, and particularly to vibration generated during operation by improving a blade implant portion when an output per unit is increased. The present invention relates to a turbine rotor blade designed to sufficiently cope with the problem.

[0002]

2. Description of the Related Art Recent steam turbines have been researched and developed to simultaneously satisfy conflicting functions such as high output per unit and shortening of the overall span. High output per unit,
In order to simultaneously shorten the overall span, it is essential to increase the annular area of the turbine blade (the total opening area through which steam passes through the blade row of the turbine blade) provided in the final stage of the low-pressure turbine. Have been.

[0003] The annular area and the increase in output per unit are, for example, as shown in FIG. 9, when the rotation speed is 3000 rpm, the tandem compound, and the low-pressure turbine is a double-flow (counter-flow) type steam turbine, as shown in FIG. The relationship between the area and the output is approximately proportional, and the required annular area can be easily obtained by setting the output per unit.

Meanwhile, in a thermal power plant, a large number of steam turbines having an output of 350 MW to 1000 MW have been conventionally manufactured.
Considering the effective recovery rate of equipment and construction costs,
It is said that a steam turbine with an output of 600 MW to 700 MW can operate most economically.

However, it can be said that a steam turbine having an output of 600 MW to 700 MW can operate most economically. However, when a tandem compound is taken as an example, as shown in FIG. Pressure turbine 2
Then, two double-flow type low-pressure turbines 3 and 4 are installed,
Since each turbine is directly connected to the shaft in a power train shape (each turbine is connected in a train shape), the span of the entire length is about 36.
m or more, and it was necessary to secure a wide installation area.

[0006] However, recent thermal power plant with the progress of the turbine technology, long blade of the turbine blades provided in the final stage of the low pressure turbine have been developed and can be the annulus area to 11m ^2, single machine The output per unit can be increased.

Further, with the development of long blades of turbine blades,
In the thermal power plant, only one low-pressure turbine 3 can be directly connected to the high-pressure turbine 1 and the medium-pressure turbine 2 in a power train shape, and the span of the entire length can be shortened.

In a recent thermal power plant, even a tandem compound in which the output is 600 MW, the number of revolutions is 3000 rpm, one high-pressure turbine, one medium-pressure turbine, and one low-pressure turbine are directly connected to each other, is used. ,
In some cases, a steam turbine having an annular area of more than 11.5 m ² of the turbine blade provided in the final stage of the low-pressure turbine may be required.

There are several problems when operating a steam turbine that requires a large annular area.

Conventionally, a turbine blade having a long blade in the final stage of a low-pressure turbine employs a titanium material having a low specific gravity and relatively low centrifugal force, instead of, for example, 12Cr steel as a blade material. .

However, the titanium material has a higher notch sensitivity than the 12Cr steel (the degree of crack development is faster).
In addition, when a reliable and economical operation is demanded because of its high price, there is a slight concern.

Further, when a turbine blade having a diameter of, for example, 40 inches or more is applied to the final stage of the low-pressure turbine, the steam turbine has a low exhaust loss and improves turbine stage efficiency, but has a high manufacturing cost and is economical. It makes driving difficult.

Further, it is said that the reason why it is difficult to adopt long blade turbine blades in the final stage of the low pressure turbine is that there are two restrictions, a centrifugal stress and a vibration stress. That is, in order to increase the annular area of the turbine blade provided in the final stage of the low-pressure turbine, either the blade length of the turbine blade is increased or the diameter of the blade root is increased. Regardless of whether the blade length is increased or the blade root diameter is increased, the centrifugal force applied to the blade effective portion, the blade implant portion, and the center hole (bore portion) of the turbine shaft increases in each case. May exceed the allowable value of the material strength.

Further, when a long blade turbine blade is used in the final stage of the low pressure turbine, there is a problem of vibration. Long blade turbine blades generate vibrations based on unexpected irregular rotation trajectories of the turbine shaft, fluctuations in the flow velocity of steam, and uneven flow.The longer the blade length and the larger the flow rate of steam, Vibration has increased, making it difficult to keep the vibration low.

As described above, in the conventional thermal power plant, in order to cope with the increase in the output per unit of the steam turbine and the shortening of the overall span, the long blade turbine blade is used in the final stage of the low pressure turbine. Even if an attempt is made to increase the annular area, there are many restrictions such as the above-mentioned centrifugal stress and vibration stress, and even if the output is 600 MW and the tandem compound is a single low-pressure turbine turbine, which is favorable for economical operation, it is difficult to realize it. .

The present invention has been made in view of such circumstances, and a long blade is employed in the final stage of a low-pressure turbine in order to simultaneously increase the output per unit of the steam turbine and shorten the overall span. In this case, it is an object of the present invention to provide a turbine rotor blade capable of performing a stable operation by guaranteeing material strength.

Specifically, the rotation speed is 3000 rpm or more,
It is an object of the present invention to provide a turbine rotor blade capable of performing stable operation even if the annular area of the final stage of the low-pressure turbine exceeds 11.5 m ² .

Further, among the tandem compound steam turbines in which each of the high pressure turbine, the medium pressure turbine, and the low pressure turbine is one unit and which is directly connected to the shaft, the long blades can be used even when the output is 600 to 700 MW. It is an object of the present invention to provide a turbine rotor blade having a reduced diameter.

[0018]

According to a first aspect of the present invention, there is provided a turbine rotor blade according to the present invention, wherein a leading edge integrally formed on a blade tip portion of a blade effective portion is formed. A blade provided with a snubber cover and a trailing edge snubber cover, a lug portion provided with a sleeve interposed at an intermediate portion of the blade effective portion, provided on a blade root portion of the blade effective portion, and fitted into an implant groove of a turbine disk. In a turbine rotor blade provided with an implanted portion, the blade implanted portion is formed on a curved surface projecting in a circumferential direction of the turbine disk.

According to a second aspect of the present invention, there is provided a turbine rotor blade according to the present invention, in which a blade tip portion of an effective blade portion has an integrally cut front edge snubber cover and a rear edge snubber cover. An edge snubber cover, a lug portion with a sleeve interposed at an intermediate portion of the blade effective portion, a blade implant portion provided at a blade root portion of the blade effective portion, and fitted into an implant groove of a turbine disk. In the turbine rotor blade, the blade-implanted portion is formed in a projecting curved surface in the circumferential direction of the turbine disk, and is implanted at a distance from the disk center line of the turbine disk toward the disk leading edge row. A groove center point is determined, and a tangent passing through an intersection of the center radius of the implanted groove from the center point of the implanted groove and the disc leading edge row and the implanted portion leading edge angle of the disc leading edge row are α, and the implanted groove center is Half And the tangent passing through the intersection of the turbine disk with the disk trailing edge row and the implanted portion trailing edge angle of the disk trailing edge row is β, the intersection of the implant groove center radius and the disk leading edge row, and the implantation When the implanted groove stagger angle between the implanted groove staggered line and the axial line connecting the groove center radius and the intersection of the disc trailing edge row is γ, the implanted portion front edge angle α, the implanted portion rear edge angle β, the implanted portion Each relational expression with the groove stagger angle γ is

## EQU3 ## An implantation groove is formed in the turbine disk so that α + β−γ ≧ 90 °.

Further, the turbine rotor blade according to the present invention has
To achieve the object, a wing as claimed in claim 3
The leading edge snubber is integrally cut into the effective wing tip.
A bar and a trailing edge snubber cover;
It has a lug with a sleeve interposed between
Installed in the mounting area of the turbine disk
In a turbine rotor blade having a blade implant portion to be
Protrude the blade implant in the circumferential direction of the turbine disk.
The turbine disk is formed on a curved surface
Away from the disk center line toward the leading edge of the disk.
Determine the implant groove center point and implant from this implant groove center point.
Position of the center radius of the groove
The distance of the intersection between the center radius of the implanted groove and the rear row of discs
DR and the width of the turbine disk is W_DAnd distance
・ Set the disk width ratio to RD = DR / W _DAnd the distance
The disk width ratio RD is

## EQU4 ## This is set in the range of RD ≦ 0.3.

According to a fourth aspect of the present invention, there is provided a turbine rotor blade according to the present invention, in which a leading edge snubber cover and a rear edge are integrally formed on a blade tip portion of a blade effective portion. An edge snubber cover, a lug portion with a sleeve interposed at an intermediate portion of the blade effective portion, a blade implant portion provided at a blade root portion of the blade effective portion, and fitted into an implant groove of a turbine disk. In the turbine rotor blade, the leading edge snubber cover extends toward the trailing edge side of the blade effective portion and is connected to the back side, and the trailing edge snubber cover extends toward the leading edge side of the blade effective portion, and And the connection point on the back side and the connection point on the abdomen side are wrapped with each other.

According to a fifth aspect of the present invention, in order to achieve the above object, the blade tip portion of the effective blade portion has a leading edge snubber cover integrally cut and a rear edge snubber cover. An edge snubber cover, a lug portion with a sleeve interposed at an intermediate portion of the blade effective portion, a blade implant portion provided at a blade root portion of the blade effective portion, and fitted into an implant groove of a turbine disk. In the turbine rotor blade, the blade implanted portion is formed on a curved surface protruding in the circumferential direction of the turbine disk, while the blade average thickness ratio obtained by dividing a blade cross section of the blade effective portion by a cord length, With the wing tip of the effective wing set in the range of 2.0% to 3.0%,
The blade length average diameter of the blade effective portion is set in a range of 6.0% to 7.0%.

According to a sixth aspect of the present invention, there is provided a turbine blade according to the present invention, wherein the turbine blade according to the first to fifth aspects is provided with an output of 600 MW or more.
A tandem compound in which one turbine unit of 700 MW, a high pressure turbine, a medium pressure turbine, and a low pressure turbine is combined, and is applied to the low pressure turbine having a ring area of 11.5 m ² or more in the final stage.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a turbine rotor blade according to the present invention will be described below with reference to the drawings and reference numerals attached to the drawings. The turbine rotor blade according to the present invention is a tandem compound in which one turbine unit of a high-pressure turbine, an intermediate-pressure turbine, and a low-pressure turbine with an output of 600 MW is combined, and has an annular area of 11 in the final stage of the low-pressure turbine. The target is a thermal power plant with a capacity of 0.5 m ² or more.

FIGS. 1 and 2 are schematic views showing a first embodiment of a turbine blade according to the present invention. FIG. 1 is a perspective view of the turbine blade viewed from the outlet side, and FIG. A-A
The sectional views taken in the direction of the arrow are shown.

The turbine rotor blade according to the present embodiment has a blade length of 40 inches or more, and has a blade effective portion 5 for causing steam to perform substantial work or for turning the flow of steam.
A snubber cover 7 integrally cut from a blade tip (blade tip) 6 of the blade effective portion 5;
And a wing implanted portion 10 which is implanted in an annular row along the circumferential direction of the wing and is integrally connected to a wing root portion (wing root portion) 9 of the wing effective portion 5.

Of the effective wing portions 5, one effective wing portion 5a and the adjacent effective wing portion 5b are provided with lugs 12a and 12b with a sleeve 11 interposed therebetween, and are generated during operation. Vibrating vibration is kept low.

The one effective blade portion 5a and the next effective blade portion 5b are both directed from the blade root portion 9 to the blade tip portion 6 and have a blade torsion that changes the blade cross section corresponding to the steam flow line. Have been.

A leading edge snubber cover 7a protruding outward is provided at the leading edge 13 of the wing tip portion 6 of the one wing effective portion 5a of the snubber cover 7,
The rear edge 14 is also provided with a rear edge snubber cover 7b protruding outwardly on the opposite side to the front edge snubber cover 7a.

A leading edge snubber cover 7a and a trailing edge snubber cover 7b are also provided on the leading edge 13 and the trailing edge 14 of the wing tip 6 of the adjacent wing effective portion 5b.

On the other hand, the blade root portion 9 of the one blade effective portion 5a
Is formed in a so-called curved entry Christmas formed in a protruding curved surface in the circumferential direction Y of the turbine disk 8 and formed in an uneven shape from the top to the bottom. Axial direction X
It is designed to be inserted toward.

The wing implant 10 in the wing root 9 of the adjacent wing effective part 5b is also formed at the curved entry Christmas similarly to the above.

As shown by the arrow AS in FIG. 2, the blade implant 10 formed at the curved entry Christmas goes from the disc trailing edge row DTE side to the disc leading edge row DLE side of the implant groove 15 provided in the turbine disk 8. At this time, it is necessary that the extra portion, which causes an increase in the centrifugal force, can be easily inserted with an extremely small excess portion.

Now, the width W of the turbine disk 8 will be described._DThe disc
Distance from the center line DCL to the disk front edge row DLE
DR_CRP to the center of the implanted groove_CAnd this plant
Groove center point RP_CThe radius of the wing ventral implant groove from R_P, Plant
Center radius of the groove_J, The radius of the groove on the back of the wing as RS
You. Also, the implantation groove center radius R_JAnd disk front row DL
Intersection P with E₁Tangent TL passing through₁And disk front row DL
Α is the leading edge angle of the implanted portion with E, and the center radius of the implanted groove
R_JOf intersection P between the disk and the trailing edge row DTE₂Tangent T through
L₂And the trailing edge angle of the implanted portion between the
β and the intersection P ₁, P₂Groove stagger that connects with a straight line
Implantation between line STL and axial line (horizontal line) HLL
Assume that the stagger angle is γ.

The present embodiment, while separating the position of the implantable groove center point RP _C from the disk centerline DCL distance DR _C, implanting portion leading edge angle alpha, after implantation edges angle beta, the respective implantation grooves stagger angle γ The relationship

## EQU5 ## It is set that α + β−γ ≧ 90 °.

In a recent steam turbine, while narrowing the blade root portion of the turbine nozzle, the mounting angle (stagger angle) of the turbine blade is increased, and the leading edge of the turbine blade is circumferentially moved with respect to the steam flow pattern. The blades are rotated, so-called ascending arrangement, to improve the blade efficiency along the streamlines of steam.

The present embodiment, attention is paid to this point, release the implantable groove center point RP _C implantable groove center radius R _J from distance DR _C only disk centerline DCL, parallel to the disk centerline DCL the distance DR between the position and the intersection P ₂ of implantation groove center radius R _J is increased, the leading edge of the effective blade portion 5 1
3 was in the upstream arranged toward the circumferential direction Y, and implantable groove center radius R _J of the airfoil thickness of the effective blade portion 5, since substantially formed symmetrically to the blade implanting portion 10 in less excess thickness and weight, The stress generated during operation can be reduced.

In this embodiment, the leading edge angle α of the implanted portion is
Since the relationship between the trailing edge angle β of the implanted portion and the stitch angle of the implanted groove stagger γ is set in the range of α + β−γ ≦ 90 °, the implanted groove of the turbine disk 8 is formed even when the blade implanted portion 10 is formed at a curved entry Christmas. 15 can be easily inserted, and the assembling work can be simplified.

The reason why the angle of attachment of the blade entry portion 10 of the curved entry Christmas to the implantation groove 15 of the turbine disk 8 is set to α + β−γ ≦ 90 ° when the blade is inserted into the turbine disk 8 is to be implanted. This is derived from the geometric condition that the part 10 does not interfere with the implantation groove 15 of the turbine disk 8.

FIG. 3 shows a second embodiment of the turbine rotor blade according to the present invention.
It is a schematic plan view showing an embodiment. Note that the same reference numerals are given to constituent parts or corresponding parts of the first embodiment.

The present embodiment, the width of the turbine disk 8 and _{W D,} before the disk from the disk center line DCL edge column D
Implantation groove center point RP separated by distance DR _C toward LE
In _C the implantation groove center radius R _J, and the disk centerline D
CL and DR distance between parallel position and the intersection point _{P 2,} when the distance disk width ratio and RD, the distance disk width ratio RD = DR / _{W D,}

## EQU6 ## RD ≦ 0.3 is set.

Generally, the wing implant portion 1 in the wing effective portion 5
The zero end portions 16a and 16b are regions that are in direct contact with the drained steam and are in a corrosive environment. Therefore, the end portion 16a of the blade implanting portion 10, 16b is designed to be lower stress values than the maximum allowable stress value sigma ₁ indicated by the broken line in FIG. 4, it is required that does not generate corrosion.

In the present embodiment, in consideration of such a point, as shown in FIG. 3, the stress value σ generated in the blade implant 10 becomes, for example, the allowable maximum stress value σ ₁ shown by a broken line in FIG. even since, so as to generate an intermediate portion in the axial direction X, as the end portion 16a, the stress values occur 16b becomes lower than the maximum allowable stress value sigma ₁ indicated by broken lines, the distance disk width ratio RD is set in a range of RD ≦ 0.3. In FIG. 4, the distance / disk width ratio RD =
0.0 is the axial stress distribution diagram of the axial entry Christmas wing implant, and the distance / disk width ratio R
D = 0.15 and RD = 0.3 respectively show an example of an axial stress distribution diagram of the wing implantation portion of the curved entry Christmas.

As described above, according to the present embodiment, the end portion 16 of the blade implant 10 under the corrosive environment due to the drainage of steam is used.
a, as stress values occurring 16b sigma becomes equal to or less than the allowable maximum stress value sigma _1, the distance disk width ratio RD, RD ≦
Since it is set in the range of 0.3, it is possible to cause the turbine blade to perform stable operation.

FIG. 5 shows a third embodiment of the turbine rotor blade according to the present invention.
It is a schematic diagram showing an embodiment.

In this embodiment, the connecting point M of the leading edge snubber cover 7a protruding outward from the back side 17 on the leading edge 13 side of the wing effective portion 5 to the wing effective portion 5 is directed toward the trailing edge 14. At the same time, the connecting point N of the trailing edge snubber cover 7 b protruding outward from the ventral side 18 on the trailing edge 14 side of the wing effective portion 5 to the wing effective portion 5 is extended toward the leading edge 13, and the connection is established. Points M and N are wrapped together.

Conventionally, the back side 17 on the front edge 13 side of the wing effective portion 5
The connecting point M of the leading edge snubber cover 7a protruding outward from the wing effective portion 5 and the trailing edge snubber cover 7 projecting outward from the ventral side 18 on the trailing edge 14 side of the wing effective portion 5
The connection point N of the b to the wing effective portion 5 is, as shown in FIG.
They were separated from each other and were not in a state of wrapping. For this reason, the leading edge snubber cover 7a and the trailing edge snubber cover 7b are provided with bending moments M _LE , M generated during operation.
_The root part of the cover CAR ₁ , CA indicated by a broken line is indicated by _TE.
Excessive stress is generated in the R _2, it had become a cause of material strength reduction.

In this embodiment, in consideration of such a point, the connecting point M of the leading edge snubber cover 7a to the wing effective portion 5 is extended toward the trailing edge 14, and the trailing edge snubber cover 7a is extended.
a connection point N of the b into the airfoil portion 5 of extending toward the front edge 13 side to wrap each other, each snapper cover 7a, the bending moment M _LE occur _7b, so it was borne by the lap portion of the M _TE In addition, the bending stress can be kept relatively low, and the turbine bucket can be operated stably.

FIG. 7 is a blade average thickness ratio distribution diagram applied to the turbine rotor blade according to the present invention.

Generally, a turbine blade has a blade length average diameter PC
When the blade cross-sectional area is reduced from D toward the blade length, centrifugal stress can be suppressed low. Further, the cord length of the blade is determined from the possibility of being inserted into the turbine disk and the appropriate pitch / cord ratio. Therefore, to keep the centrifugal stress generated during operation low, it is determined by the blade thickness distribution.

The blade average thickness ratio distribution applied to the turbine blade according to the present embodiment is plotted based on experimental values. As shown in FIG. 7, the upper blade average thickness ratio distribution diagram UAT and the lower limit It is divided into a blade average thickness ratio distribution diagram LAT. The upper limit average blade thickness distribution map UAT and the lower limit blade average thickness ratio distribution map LAT are defined as: When the average blade thickness is increased, a high centrifugal stress is generated in the blade, and when the average thickness is reduced, the rigidity of the blade is reduced. Lowering and increasing bending stress due to steam. In FIG. 7, the average blade thickness ratio is the average thickness obtained by dividing the blade cross section by the cord length of the cross section by%
Displayed with.

In this embodiment, when the blade average thickness ratio is determined from FIG. 7, the blade average diameter PCD is 6.0% to 7.0%, and the blade tip portion is 2.0% to 3.0%. Is the most preferable numerical value.

As described above, in this embodiment, the blade average thickness ratio is set in the range of 6.0% to 7.0% in the blade length average diameter PCD, and 2.0% to 3.0% in the blade tip portion. Since it is set to the range of 0%, the stress generated by the centrifugal force can be suppressed low, and the bending stress and the vibration stress can be sufficiently coped with the steam.

[0054]

As described above, the turbine rotor blade according to the present invention is formed at the curved entry Christmas in which the blade implantation portion is formed into a protruding curved surface in the circumferential direction of the turbine disk. Since the blade implant portion is fitted in the implant groove provided in the turbine disk, it is possible to cope with the centrifugal force generated during operation with a margin and to perform stable operation.

Further, in the turbine rotor blade according to the present invention, the leading edge of the blade effective portion provided at the blade implant portion formed at the curved entry Christmas is oriented in the circumferential direction of the turbine disk. While reducing the excess wall thickness by placing it, the installation angle of the turbine disk stud groove for inserting the wing stud portion of the curved entry Christmas is set to an appropriate angle, so that the stress generated during operation can be reduced and In addition, the assembling work at the time of insertion can be facilitated.

Further, in the turbine rotor blade according to the present invention, the distance and the disk width are adjusted so that the stress generated during operation is lower than the allowable maximum stress value at both ends of the blade implant inserted into the implant groove of the turbine disk. Since the ratio is set, corrosion due to contact with the drained steam can be suppressed to a low level.

Further, in the turbine rotor blade according to the present invention, the leading edge snubber cover and the trailing edge snubber cover are integrally formed on the blade tip portion, and the leading edge snubber cover and the trailing edge snubber cover are provided on the effective blade portion. Since the connection points are wrapped with each other and the wrapped portion is also given a bending moment, the bending stress can be kept relatively low.

Further, in the turbine rotor blade according to the present invention, the blade average thickness ratio is set to an appropriate value for each of the blade length average diameter and the blade tip portion. On the other hand, it is possible to respond with a margin.

[Brief description of the drawings]

FIG. 1 is a perspective view of a turbine blade according to a first embodiment of the present invention, as viewed from an outlet side of the turbine blade.

FIG. 2 is a cross-sectional plan view taken along the line AA of FIG. 1;

FIG. 3 is a schematic plan view showing a second embodiment of the turbine bucket according to the present invention.

FIG. 4 is an axial stress distribution diagram of a conventional blade implant showing the axial stress of the blade implant.

FIG. 5 is a schematic plan view of a blade tip showing a third embodiment of the turbine bucket according to the present invention.

FIG. 6 is a schematic perspective view showing a blade tip portion of a conventional turbine blade.

FIG. 7 is a blade average thickness ratio distribution diagram applied to the turbine rotor blade according to the present invention.

FIG. 8 is a schematic system diagram showing a conventional steam turbine plant.

FIG. 9 is a diagram showing the relationship between the turbine output per unit and the annular area of the turbine moving blade in the final stage of the low-pressure turbine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-pressure turbine 2 Medium-pressure turbine 3,4 Low-pressure turbine 5,5a, 5b Effective blade part 6 Blade tip part 7 Snubber cover 7a Leading edge snubber cover 7b Trailing edge snubber cover 8 Turbine disk 9 Blade root part 10 Blade implant part 11 Sleeve 12a, 12b lug part 13 front edge 14 rear edge 15 implantation groove 16a, 16b end part 17 back side 18 ventral side

Claims (6)

[Claims] 1. A wing tip portion of an effective wing portion includes a leading edge snubber cover and a trailing edge snubber cover which are integrally cut, and a lug portion is provided at a middle portion of the effective wing portion with a sleeve interposed therebetween. In a turbine rotor blade provided at a blade root portion of a blade effective portion and fitted with a blade implantation groove of a turbine disk, the blade implantation portion has a curved surface protruding in a circumferential direction of the turbine disk. A turbine rotor blade formed in the shape of: 2. A wing tip portion of an effective wing portion is provided with a leading edge snubber cover and a trailing edge snubber cover which are integrally cut,
A lug portion is provided with a sleeve interposed in the middle of the effective blade portion, a lug portion is provided at a blade root portion of the effective blade portion, and a turbine blade having a blade implant portion fitted into an implant groove of a turbine disk, The blade implant portion is formed on a curved surface protruding in the circumferential direction of the turbine disk, and the implant groove center point is determined at a distance from the disk center line of the turbine disk toward the disk front edge row, Let α be the implanted portion leading edge angle between a tangent line passing through the intersection of the implanted groove center radius from the implanted groove center point and the disk leading edge row and the disk leading edge row, and set the implanted groove center radius and the disk of the turbine disk to α. The angle of the trailing edge of the implanted portion between the tangent passing through the intersection with the trailing edge row and the disc trailing edge row is β, the intersection of the implanted groove center radius and the disc leading edge row, the implanted groove center radius and the data When the implanted groove stagger angle between the implanted groove staggered line and the axial line connecting the intersection with the disc trailing edge row is γ, the implanted portion front edge angle α, the implanted portion rear edge angle β,
A turbine rotor blade characterized in that an implantation groove is formed in the turbine disk so that a relational expression with respect to the implantation groove stagger angle γ is in the range of α + β−γ ≧ 90 °. 3. A wing tip portion of an effective wing portion is provided with a leading edge snubber cover and a trailing edge snubber cover which are integrally cut,
A lug portion is provided with a sleeve interposed in the middle of the effective blade portion, a lug portion is provided at a blade root portion of the effective blade portion, and a turbine blade having a blade implant portion fitted into an implant groove of a turbine disk, The blade implant portion is formed on a curved surface protruding in the circumferential direction of the turbine disk, and the implant groove center point is determined at a distance from the disk center line of the turbine disk toward the disk front edge row, a position parallel implantation groove center radius of the disc center line from implant groove center point, the distance of the intersection between the implantable groove center radius disk trailing edge column and DR, the width of the turbine disc and W _D, the distance disk width ratio RD = DR / _{W D}
Wherein the distance / disk width ratio RD is set in the range of RD ≦ 0.3. 4. A wing tip portion of an effective wing portion is provided with a leading edge snubber cover and a trailing edge snubber cover which are integrally cut,
A lug portion is provided with a sleeve interposed in the middle of the effective blade portion, a lug portion is provided at a blade root portion of the effective blade portion, and a turbine blade having a blade implant portion fitted into an implant groove of a turbine disk, While extending the leading edge snubber cover toward the trailing edge side of the wing effective portion and connecting it to the back side,
A turbine rotor blade wherein the trailing edge snubber cover extends toward the leading edge side of the blade effective portion and is connected to the ventral side, and the dorsal connection point and the ventral connection point are wrapped together. . 5. A wing tip portion of an effective wing portion is provided with a leading edge snubber cover and a trailing edge snubber cover which are integrally cut,
A lug portion is provided with a sleeve interposed in the middle of the effective blade portion, a lug portion is provided at a blade root portion of the effective blade portion, and a turbine blade having a blade implant portion fitted into an implant groove of a turbine disk, The blade implant portion is formed on a curved surface protruding in the circumferential direction of the turbine disk, while the blade average thickness ratio obtained by dividing a blade cross section of the blade effective portion by a cord length is defined as a blade tip portion of the blade effective portion. In the range of 2.0% to 3.0%, the average length of the wing effective portion is 6.
A turbine blade set in a range of 0% to 7.0%. 6. The turbine rotor blade according to claim 1,
A tandem compound combining an output of 600 MW to 700 MW, a high-pressure turbine, a medium-pressure turbine, and a low-pressure turbine, each having a ring area of 11.5 m ² or more in the final stage of the low-pressure turbine. Characteristic turbine blade.