Turbine bucket

• US 6,579,066 B1
• Filed: 10/12/2001
• Issued: 06/17/2003
• Est. Priority Date: 10/15/1999
• Status: Expired due to Term

• Current Assignee: mitsubishi hitachi power systems, ltd. (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamashita, Yutaka, Saito, Eiji, Ikeuchi, Kazuo, Takasumi, Masakazu, Yamazaki, Yoshiaki, Namura, Kiyoshi, Shikano, Yoshio, Katayose, Masumi
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): Kershteyn, Igor
• Application Number:
  US09/958,604
• Time in Patent Office: 613 Days
• Field of Search: 416/243, 416/DIG.2, 416/DIG.5
• US Class Current: 416/243
• CPC Class Codes: F01D 5/141 Shape, i.e. outer, aerodynamic form F01D5/148 - F01D5/20 take precedence; blade construction F01D5/147
• CPC Class Codes: F01D 5/225 by shrouding
• CPC Class Codes: F01D 5/3023 of radial insertion type, e.g. in individual recesses
• CPC Class Codes: F05D 2240/301 Cross-sectional characteristics
• CPC Class Codes: Y10S 416/02 Formulas of curves
• CPC Class Codes: Y10S 416/05 Variable camber or chord length

Abstract

The present invention is a turbine bucket for at the low pressure last stage of a steam turbine and in which the adjacent blades are connected without using a connecting member at a blade intermediate portion. A turbine bucket of the present invention is formed that the blade sectional configuration is twisted from a blade root portion to a blade tip side, and when assuming two axial directions in a blade section of the bucket on horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at predetermined heights from the blade root portion of the turbine bucket are formed in a range of ±0.3 mm from respective points defining blade section configurations.

Claims

1. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

2. A turbine bucket of claim 1, characterized in that the turbine buckets are disposed by successively engaging the same with a disk outer circumferential portion of a turbine rotor, and the axial direction of the turbine rotor is defined as X axis and the circumferential direction of the turbine rotor is defined as Y axis.

3. A turbine bucket of claim 1, characterized in that the turbine buckets of the number of from 120 to 127 are disposed over the entire outer disk circumference of a turbine rotor.

4. A turbine bucket of claim 1, characterized in that the turbine bucket is formed in a configuration by proportionally reducing or expanding the series of coordinate points of the respective blade sections.

5. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at height 0 mm from the blade root portion of the turbine bucket being as follows,

6. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at height 38 mm from the blade root portion of the turbine bucket being as follows,

7. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

8. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.15 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

9. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.15 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

10. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts, and further being provided with a shroud which is formed at a tip portion of the bucket while being extended in the back side and in the front side of the bucket;

the blade section at the blade root portion of the turbine bucket being as follows,

11. A turbine bucket of claim 10, characterized in that the turbine buckets are successively engaged with a disk outer circumferential portion of a turbine rotor and are disposed so that the shroud at the blade front side of one bucket contacts with the shroud at the blade back side of another adjacent bucket each other and the shroud is formed in such a manner that a contacting face formed between the blade back side shroud of the one bucket and the blade front side shroud of the other bucket is disposed in a region at the upstream side from a blade front of a blade section at the blade tip portion of the one turbine bucket.

12. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts, and further being provided with a shroud which is formed at a tip portion of the bucket while being extended in the back side and in the front side of the bucket;

the blade section at the blade root portion of the turbine bucket being as follows,

13. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

14. A turbine bucket of claim 13, characterized in that the turbine buckets of the number of from 114 to 120 are disposed over the entire outer disk circumference of a turbine rotor.

15. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at height 0 mm from the blade root portion of the turbine bucket being as follows,

16. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at height 38 mm from the blade root portion of the turbine bucket being as follows,

17. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

18. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.15 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

19. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.15 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,

20. A turbine bucket which is formed in such a manner that the blade sectional configuration is twisted from a blade root portion to a blade tip side, characterized in that when assuming two axial directions in a blade section of the bucket along horizontal plane and taking one axial direction as X axis and the other axial direction perpendicular to X axis as Y axis, the blade sections at the following heights from the blade root portion of the turbine bucket are formed in a range of ±

0.3 mm from series of points defining blade section configurations as defined in the following charts;

the blade section at the blade root portion of the turbine bucket being as follows,