Assembly type nozzle diaphragm, and method of assembling the same

• US 20040253095A1
• Filed: 07/01/2004
• Published: 12/16/2004
• Est. Priority Date: 07/19/2001
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nakama, Yuji, Sasaki, Takashi, Imai, Kenichi
• Granted Patent: US 7,179,052 B2
• Time in Patent Office: Days
• US Class Current: 415/191
• CPC Class Codes: F01D 25/246 Fastening of diaphragms or stator-rings
• CPC Class Codes: F01D 9/042 fixing blades to stators fixing stator-rings in the casing or to each other F01D25/246
• CPC Class Codes: F05D 2230/61 using limited numbers of standard modules which can be adapted by machining
• CPC Class Codes: F05D 2240/10 Stators
• CPC Class Codes: Y10T 29/49323 Assembling fluid flow directing devices, e.g., stators, diaphragms, nozzles

Abstract

An assembled nozzle diaphragm according to the present invention includes a diaphragm outer ring 15 having a groove 23 opened toward an inner diameter side to be continuous in an inner peripheral direction of the diaphragm outer ring 15; a diaphragm inner ring 16 having a groove 28 opened toward an outer diameter side to be continuous in an outer peripheral direction of the diaphragm inner ring 16; and a nozzle blade 14 having a diaphragm outer ring insertion portion 12 on one end and a diaphragm inner ring insertion portion 13 on the other end, in which the groove 23 opened toward the inner diameter side of the diaphragm outer ring 15 and the diaphragm outer ring insertion portion 12 of the nozzle blade 14 are shaped to be fitted to each other only in a circumferential direction of each of the groove 23 and the diaphragm outer ring insertion portion 12, and in which the groove 28 opened toward the outer diameter side of the diaphragm inner ring 16 and the diaphragm inner ring insertion portion 13 of the nozzle blade 14 are shaped to be fitted to each other only in one of circumferential direction and diameter direction of each of the groove 28 and the diaphragm inner ring insertion portion 16. According to this structure, the assembled nozzle diaphragm and an its assembling method can be provided so as to be capable of modifying and simplifying a structure of a turbine nozzle and facilitating assembling working without performing welding operation.

Claims

1. An assembled nozzle diaphragm comprising:

a diaphragm outer ring having a groove opened toward an inner diameter side to be continuous in an inner peripheral direction of the diaphragm outer ring;

a diaphragm inner ring having a groove opened toward an outer diameter side to be continuous in an outer peripheral direction of the diaphragm inner ring; and

a nozzle blade having an insertion portion for the diaphragm outer ring provided on one end and an insertion portion for the diaphragm inner ring provided on the other end,

wherein the groove opened toward the inner diameter side of the diaphragm outer ring and the diaphragm outer ring insertion portion of the nozzle blade are shaped to be fitted to each other only in a circumferential direction of each of the groove and the diaphragm outer ring insertion portion, and the groove opened toward the outer diameter side of the diaphragm inner ring and the diaphragm inner ring insertion portion of the nozzle blade are shaped to be fitted to each other only in one of circumferential direction and diameter direction of each of the groove and the diaphragm inner ring insertion portion.

2. The assembled nozzle diaphragm according to claim 1, wherein an upstream side surface of the diaphragm outer ring insertion portion, which is directed toward a flow of a fluid, is formed in combination of a protruded hook portion and a stepped block portion provided to be continuous to the protruded hook portion, and the protruded hook portion and the stepped block portion extend in the circumferential direction.

3. The assembled nozzle diaphragm according to claim 1, wherein the diaphragm inner ring insertion portion has a convex columnar piece formed at an intermediate position and the convex columnar piece extends in the circumferential direction.

4. The assembled nozzle diaphragm according to claim 1, wherein the diaphragm outer ring has a cap groove formed in the circumferential direction, the cap groove including a protruded hook portion at an inlet.

5. The assembled nozzle diaphragm according to claim 1, wherein the diaphragm inner ring has a concave groove formed in the circumferential direction.

6. The assembled nozzle diaphragm according to claim 1, wherein a fitting gap between the diaphragm outer ring insertion portion and the diaphragm outer ring is set to be in a range of 0.03 to 0.12 millimeters.

7. The assembled nozzle diaphragm according to claim 6, wherein the fitting gap set to be in the range of 0.03 to 0.12 millimeters between the diaphragm outer ring insertion portion and the diaphragm outer ring is at least one of a gap between a surface on a head side of the diaphragm outer ring insertion portion parallel to a flow of a fluid and the diaphragm outer ring and a gap between a surface on an upstream side surface of the diaphragm outer ring insertion portion in the diameter direction and the diaphragm outer ring.

8. The assembled nozzle diaphragm according to claim 1, wherein a fitting gap between the diaphragm inner ring insertion portion and the diaphragm inner ring is set to be in a range of 0.03 to 0.12 millimeters.

9. The assembled nozzle diaphragm according to claim 8, wherein the fitting gap set to be in the range of 0.03 to 0.12 millimeters between the diaphragm inner ring insertion portion and the diaphragm inner ring is a gap between a surface of a columnar piece of the diaphragm inner ring insertion portion in the diameter direction and the diaphragm inner ring.

10. The assembled nozzle diaphragm according to claim 1, wherein the diaphragm outer ring insertion portion is formed in combination of protruded hook portions provided on an upstream side surface directed toward a flow of a fluid and a downstream side surface along the flow of the fluid, respectively, stepped block portions provided to be continuous to the respective protruded hook portions and protruded base portions provided to be continuous to the respective stepped block portions.

11. The assembled nozzle diaphragm according to claim 1, wherein the diaphragm outer ring insertion portion is constituted in combination of a columnar piece directed toward the diameter direction and a protruded base portion provided to be continuous to the columnar piece.

12. The assembled nozzle diaphragm according to claim 1, wherein an upstream side surface of the diaphragm outer ring insertion portion which is directed toward a flow of a fluid is formed in combination of a protruded hook portion, a stepped block portion provided to be continuous to the hook portion, and a protruded base portion provided to be continuous to the block portion, a ring piece is attached to the block portion, and fixing means is provided on the diaphragm outer ring so as to apply a pressing force to the diaphragm outer ring insertion portion.

13. The assembled nozzle diaphragm according to claim 1, wherein an upstream surface of the diaphragm outer ring insertion portion which is directed toward a flow of a fluid is formed in combination of a protruded hook portion, a stepped block portion provided to be continuous to the hook portion, and a protruded base portion provided to be continuous to the block portion, and a shakiness prevention piece is provided on a fitting surface on which the diaphragm outer ring insertion portion is fitted to the diaphragm outer ring.

14. The assembled nozzle diaphragm according to claim 13, wherein the shakiness prevention piece is provided at least one of a gap between a surface on a head side of the diaphragm outer ring insertion portion parallel to the flow of the fluid and the diaphragm outer ring and a gap between a surface of the upstream side surface of the diaphragm outer ring insertion portion in the diameter direction and the diaphragm outer ring.

15. The assembled nozzle diaphragm according to claim 13, wherein the shakiness prevention piece is provided in a corner of the upstream side surface on a head side of the diaphragm outer ring insertion portion.

16. The assembled nozzle diaphragm according to claim 1, wherein a plurality of the nozzle blades each supported by the diaphragm outer ring and the diaphragm inner ring are arranged at counterflow positions along a flow of a fluid to be divided, and the plurality of nozzle blades arranged at the counterflow positions are supported by the single diaphragm inner ring.

17. The assembled nozzle diaphragm according to claim 1, wherein a plurality of the nozzle blades each supported by the diaphragm outer ring and the diaphragm inner ring are arranged at counterflow positions along a flow of a fluid to be divided, and the diaphragm outer ring insertion portion of each of the plurality of nozzle blades arranged at the counterflow positions is supported by the single diaphragm outer ring.

18. An assembled nozzle diaphragm comprising:

a diaphragm outer ring having a groove opened toward an inner diameter side to be continuous in an inner peripheral direction of the diaphragm outer ring;

a diaphragm inner ring having a groove opened toward an outer diameter side to be continuous in an outer peripheral direction of the diaphragm inner ring; and

a nozzle blade having an insertion portion for the diaphragm outer ring provided on one end and an insertion portion for the diaphragm inner ring provided on the other end,

wherein the diaphragm inner ring includes a nozzle blade inner periphery-side member formed integrally with the nozzle blade.

19. The assembled nozzle diaphragm according to claim 18, wherein the diaphragm outer ring includes a shakiness prevention piece on a fitting surface on which the diaphragm outer ring insertion portion is fitted into the diaphragm outer ring.

20. An assembled nozzle diaphragm comprising:

a diaphragm outer ring having a groove opened toward an inner diameter side to be continuous in an inner peripheral direction of the diaphragm outer ring; and

a nozzle blade having an insertion portion for the diaphragm outer ring provided on one end and a diaphragm inner ring provided on the other end,

wherein a plate is inserted into the diaphragm inner ring.

21. A method of assembling a nozzle diaphragm which comprises:

a diaphragm outer ring having a groove opened toward an inner diameter side to be continuous in an inner peripheral direction of the diaphragm outer ring;

a diaphragm inner ring having a groove opened toward an outer diameter side to be continuous in an outer peripheral direction of the diaphragm inner ring; and

a nozzle blade having an insertion portion for the diaphragm outer ring provided on one end and an insertion portion for the diaphragm inner ring provided on the other end,

said method comprising the steps of;

working the diaphragm outer ring to be divided in half to a diaphragm outer ring upper half portion and a diaphragm outer ring lower half portion at a horizontal joint surface position substantially at 180 degrees so as to constitute the diaphragm outer ring of a ring body;

working the diaphragm inner ring to be divided in half to a diaphragm inner ring upper half portion and a diaphragm inner ring lower half portion at a horizontal joint surface position substantially at 180 degrees so as to constitute the diaphragm inner ring of the ring body;

fitting the diaphragm outer ring insertion portion of the nozzle blade from a horizontal joint surface of one of the diaphragm outer ring upper half portion and the diaphragm outer ring lower half portion toward a horizontal joint surface of the other one of the diaphragm outer ring upper half portion and the diaphragm outer ring lower half portion to sequentially insert, one by one, the nozzle blades of a preset number in a circumferential direction;

fixing the plurality of inserted nozzle blades by stopper pieces on the horizontal joint surfaces of the one half portion and on the horizontal joint surface of the other half portion, respectively;

inserting the diaphragm inner ring upper half portion and the diaphragm inner ring lower half portion into the inner ring insertion portion of the nozzle blade from an inside diameter direction of the inner ring insertion portion;

fixing the plurality of inserted nozzle blades by stopper pieces on the horizontal joint surface of the inserted diaphragm inner ring upper half portion and the horizontal joint surface of the inserted diaphragm inner ring lower half portion, respectively; and

fixing the diaphragm inner ring upper half portion and the diaphragm outer ring upper half portion integrated with the nozzle blades of the preset number to the diaphragm inner ring lower half portion and the diaphragm outer ring lower half portion integrated with the nozzle blades of the preset number on the respective horizontal joint surfaces.

22. The nozzle diaphragm assembling method according to claim 21, wherein a fitting gap between the diaphragm outer ring insertion portion and the diaphragm outer ring is set to be in a range of 0.03 to 0.12 millimeters.

23. The nozzle diaphragm assembling method according to claim 22, wherein the fitting gap set to be in the range of 0.03 to 0.12 millimeters between the diaphragm outer ring insertion portion and the diaphragm outer ring is at least one of a gap between a surface on a head side of the diaphragm outer ring insertion portion parallel to a flow of a fluid and the diaphragm outer ring and a gap between a surface on an upstream side surface of the diaphragm outer ring insertion portion in the diameter direction and the diaphragm outer ring.

24. The nozzle diaphragm assembling method according to claim 21, wherein a fitting gap between the diaphragm inner ring insertion portion and the diaphragm inner ring is set to be in a range of 0.03 to 0.12 millimeters.

25. The nozzle diaphragm assembling method according to claim 24, wherein the fitting gap set to be in the range of 0.03 to 0.12 millimeters between the diaphragm inner ring insertion portion and the diaphragm inner ring is in the diameter direction of a columnar piece of the diaphragm inner ring insertion portion.