JP2014080926A - Nozzle diaphragm connected body and steam turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nozzle diaphragm connected body which has a water content flow passage inside and in which water content retention in the water content flow passage is restricted.SOLUTION: A nozzle diaphragm connected body of an embodiment includes a plurality of nozzle diaphragm stages, the water content flow passage, a positioning pin, and a water content discharge hole. The pluralities of nozzle diaphragm stages are connected to each other. The water content flow passage is formed between the nozzle diaphragm stages adjacent to each other so as to extend in a circumferential direction. The positioning pin is arranged between the nozzle diaphragm stages adjacent to each other so as to extend in a radial direction. Also the positioning pin has a small-diameter part which has smaller diameter than that of other parts and is positioned on an overlapping part with the water content flow passage. The water content discharge hole connects between the water content flow passage and the periphery of the plurality of nozzle diaphragm stages and discharges the water content in the water content flow passage to outside.

Description

  Embodiments described herein relate generally to a nozzle diaphragm connector and a steam turbine.

  Conventionally, a steam turbine having a nozzle diaphragm is known. The nozzle diaphragm is configured, for example, by arranging a plurality of nozzle plates in the circumferential direction between an outer ring and an inner ring (see, for example, Patent Document 1). Then, the use of a nozzle diaphragm coupling body, which is a so-called tie-in type nozzle diaphragm, in which a plurality of such nozzle diaphragms are coupled has been studied.

  FIG. 10 is an external view showing an example of a nozzle diaphragm connector. In the nozzle diaphragm connector 30, a nozzle diaphragm stage 31 on the steam inflow side and a nozzle diaphragm stage 32 on the steam discharge side are connected by a plurality of vertical joint bolts 33. The nozzle diaphragm stage 31 on the steam inflow side includes an outer ring 311, a nozzle plate 312, and an inner ring 313. Similarly, the nozzle diaphragm stage 32 on the steam discharge side is also composed of an outer ring 321, a nozzle plate (not shown), and an inner ring (not shown).

  The nozzle diaphragm coupling body 30 is generally composed of an upper coupling body 301 and a lower coupling body 302 in consideration of assembling and disassembling properties. That is, the outer ring 311 of the nozzle diaphragm stage 31 on the steam inflow side is composed of an upper outer ring 314 and a lower outer ring 315, and the inner ring 313 is composed of an upper inner ring 317 and a lower inner ring 318. The outer ring 321 of the nozzle diaphragm stage 32 on the steam discharge side is composed of an upper outer ring 324 and a lower outer ring 325, and the inner ring (not shown) is composed of an upper inner ring and a lower inner ring. The upper coupling body 301 and the lower coupling body 302 are fixed by upper and lower coupling means such as an upper and lower clamping bolt (not shown).

  FIG. 11 is a plan view showing a contact surface with the upper coupling body 301 in the lower coupling body 302 in FIG. 10. On the contact surface between the lower outer ring 315 on the steam inflow side and the lower outer ring 325 on the steam discharge side, an uneven portion 35 that is a fitting portion for improving assemblability is provided. Usually, the concavo-convex portion 35 is provided so that the entire contact surface between the outer ring 311 on the steam inflow side and the outer ring 321 on the steam discharge side makes one round in the circumferential direction. Further, if the size of the concave portion and the convex portion are the same, they interfere with each other at the time of assembling and the assemblability deteriorates. Therefore, the size of the concave portion in the radial direction and the axial direction is made larger than that of the convex portion. For this reason, a slight gap is formed between the concave portion and the convex portion.

  For such a connecting body 30, the upper connecting body 301 and the lower connecting body 302 are fixed by upper and lower clamping bolts or the like (not shown). However, since a high steam pressure is applied during operation of the steam turbine, It deform | transforms so that between the body 301 and the lower coupling body 302, especially between steam inflow sides may open. At this time, since a slight gap is formed in the nozzle diaphragm connector 30 by the uneven portion 35, steam enters the portion to form water droplets, and the gap in the uneven portion 33 is substantially equal to the moisture channel 36. Become. Then, as time elapses, moisture stays in sequence from the moisture channel 36 below the lower coupling body 302.

  For example, when the longitudinal joint bolt 33 is arranged so as to overlap the moisture flow path 36, the longitudinal joint bolt 33 causes stress corrosion cracking (SCC) because the retention of moisture for a long time brings about a severe environment against corrosion. There is a fear. The corroded vertical joint bolt 33 is cracked and may eventually break. In order to keep the vertical joint bolt 33 in a healthy state, it is necessary to discharge the moisture staying in the moisture channel 36 to the outside.

  Further, the nozzle diaphragm connector 30 is provided with positioning pins 34 (FIG. 10) in order to make the positional relationship between the nozzle diaphragm stage 31 on the steam inflow side and the nozzle diaphragm stage 32 on the steam discharge side suitable for assembly. Has been inserted. The positioning pin 34 is inserted so as to extend in the axial direction similarly to the vertical joint bolt 33, for example. The positioning pin 34 is inserted before the vertical joint bolt 33 at the time of assembling so that the positional relationship between the nozzle diaphragm stage 31 on the steam inflow side and the nozzle diaphragm stage 32 on the steam discharge side becomes appropriate.

  However, since the clearance between the positioning pin 34 and the positioning pin hole into which the positioning pin 34 is inserted is small, the positioning pin 34 stops halfway during insertion when the axial thickness of the nozzle diaphragm connector 30 increases. Therefore, it becomes difficult to insert completely. Such a tendency becomes conspicuous in the case of a steam turbine having a large output, particularly one used for a steam turbine applied to nuclear power generation.

  In order to avoid such an event, when the thickness of the nozzle diaphragm connector 30 in the axial direction is large, it has been studied to insert the positioning pin 34 from the radial direction as shown in FIG. When the positioning pin 34 is inserted from the radial direction as described above, the positioning pin 34 is provided on the contact surface portion between the nozzle diaphragm stage 31 on the steam inflow side and the nozzle diaphragm stage 32 on the steam discharge side from the viewpoint of exerting the positioning function. It is necessary to insert. However, since the water flow path 36 exists so as to make one round in the circumferential direction at the contact surface portion between the nozzle diaphragm stage 31 on the steam inflow side and the nozzle diaphragm stage 32 on the steam discharge side, the positioning pin 34 from the radial direction. Is inserted, the moisture channel 36 is closed by the positioning pin 34, and moisture stays in this portion.

JP 2004-176548 A

  As described above, with respect to the nozzle diaphragm connected body, there is a possibility that water may stay in the substantial water flow path formed by the gaps between the concavo-convex portions, particularly the lower water flow path. Further, among the nozzle-diaphragm coupling bodies, in which the positioning pin is inserted from the radial direction, the moisture channel may be blocked by the positioning pin, and moisture may stay in that portion.

  An embodiment of the present invention has been made in order to solve the above-described problem, and has a water flow channel inside, and uses a nozzle diaphragm connector in which moisture retention in the water flow channel is suppressed, and the same. The purpose is to provide a steam turbine.

  The nozzle diaphragm coupling body of the embodiment includes a plurality of nozzle diaphragm stages, a water flow channel, a positioning pin, and a water discharge hole. The plurality of nozzle diaphragm paragraphs are connected to each other. The moisture channel is formed to extend in the circumferential direction between adjacent nozzle diaphragm stages. The positioning pins are arranged so as to extend in the radial direction between adjacent nozzle diaphragm stages. Further, the positioning pin has a small-diameter portion that is smaller in diameter than other portions in the portion that overlaps the moisture flow path. The moisture discharge hole connects the moisture channel and the outer periphery of the plurality of nozzle diaphragm stages, and drains the moisture in the moisture channel to the outside.

  According to the nozzle diaphragm coupling body of the embodiment, the positioning pin having a small diameter portion is used and the moisture discharge hole is provided to discharge moisture in the moisture flow path to suppress moisture retention, such as a vertical joint bolt. Stress corrosion cracking can be suppressed.

A sectional view showing one embodiment of a steam turbine. The external view which shows one Embodiment of a nozzle diaphragm coupling body. The external view which shows one Embodiment of a lower coupling body. The partial enlarged plan view which expands and shows the contact surface with the upper coupling body in the lower coupling body shown in FIG. FIG. 5 is a partial cross-sectional view of the lower connector shown in FIG. 4 along the line AA. BB sectional drawing of the lower coupling body shown in FIG. CC sectional drawing of the lower coupling body shown in FIG. The top view of the lower coupling body shown in FIG. The DD line partial expanded sectional view of the lower coupling body shown in FIG. The external view which shows an example of the conventional nozzle diaphragm coupling body. The top view which shows the contact surface with the upper coupling body in the lower coupling body shown in FIG. The external view which shows an example of the nozzle diaphragm coupling body which inserted the positioning pin from radial direction.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a meridional cross-sectional view illustrating an example of a steam turbine according to an embodiment.
The steam turbine 10 has a casing 13 provided with a main steam pipe 11 for introducing steam, which is a working fluid, an exhaust passage 12 for guiding the steam that has passed through the inside to the outside, and the like. A turbine rotor 15 in which moving blades 14 are implanted so as to constitute a plurality of turbine stages is provided in the casing 13.

  In the casing 13, a nozzle diaphragm coupling body 18 in which two adjacent nozzle diaphragm stages 16 and 17 are coupled to each other is disposed. The nozzle diaphragm connector 18 is a so-called tie-in type nozzle diaphragm. For example, a plurality of nozzle diaphragm connectors 18 are arranged in the casing 13. When a plurality of nozzle diaphragm coupling bodies 18 are arranged, for example, nozzle diaphragm paragraphs 16 and 17 of each nozzle diaphragm coupling body 18 are sequentially arranged between the moving blades 14 of each paragraph.

  FIG. 2 is an external view showing an embodiment of the nozzle diaphragm connector 18. FIG. 3 is an external view showing a lower connecting body which is a lower half portion of the nozzle diaphragm connecting body 18 shown in FIG.

  As shown in FIG. 2, the nozzle diaphragm connector 18 can be divided vertically by a horizontal plane passing through the center, and is composed of an upper connector 181 that is the upper half and a lower connector 182 that is the lower half. It is configured. The nozzle diaphragm connector 18 includes two nozzle diaphragm stages 16 and 17, which are connected in the axial direction by a plurality of vertical joint bolts 19.

  The nozzle diaphragm stage 16 on the steam inflow side includes an outer ring 161, a nozzle plate 162, and an inner ring 163. A plurality of nozzle plates 162 are arranged in the circumferential direction between the outer ring 161 and the inner ring 163. The outer ring 161 can be divided into upper and lower parts by a horizontal plane passing through the center, and is composed of an upper outer ring 164 and a lower outer ring 165. The inner ring 163 can also be divided up and down by a horizontal plane passing through the center, and is composed of an upper inner ring 167 and a lower inner ring 168.

  The nozzle diaphragm stage 17 on the steam discharge side has basically the same structure as the nozzle diaphragm stage 16 on the steam inflow side. That is, it is composed of an outer ring 171, a nozzle plate 172 (FIG. 3), and an inner ring. A plurality of nozzle plates are arranged in the circumferential direction between the outer ring 171 and the inner ring. The outer ring 171 can be divided up and down by a horizontal plane passing through the center, and is composed of an upper outer ring 174 and a lower outer ring 175. The inner ring can also be divided up and down by a horizontal plane passing through the center, and is composed of an upper inner ring and a lower inner ring 178 (FIG. 3).

  The nozzle diaphragm stage 16 on the steam inflow side and the nozzle diaphragm stage 17 on the steam discharge side are connected to the outer ring 161 and the outer ring 171 by a plurality of vertical joint bolts 19 inserted in the axial direction. The plurality of vertical joint bolts 19 are arranged at substantially equal intervals in the circumferential direction of the outer rings 161 and 171, for example.

  Further, a positioning pin 20 for properly matching the positional relationship during assembly is disposed on a contact surface portion between the outer ring 161 on the steam inflow side and the outer ring 171 on the steam discharge side. The positioning pin 20 is inserted from the outer peripheral side into a contact surface portion between the outer ring 161 on the steam inflow side and the outer ring 171 on the steam discharge side, and is disposed so as to extend in the radial direction. For example, the positioning pins 20 are provided two on the left and one on the left and one on the top and the bottom. When the positioning pins 20 are provided only on the left and right sides, the outer ring 161 and the outer ring 171 may be shifted in the left-right direction. By providing the positioning pins 20 on the upper and lower sides as well, the shift in the left-right direction can be suppressed.

  For example, the upper coupling body 181 is provided with one positioning pin 20 on the upper side, one on the left and right in the vicinity of the contact surface with the lower coupling body 182. The left and right positioning pins 20 of the upper coupling body 181 are preferably disposed below the longitudinal joint bolt 19 disposed at the lowermost position in the upper coupling body 181, for example. The lower connector 182 is provided with one positioning pin 20 on the left and right sides near the contact surface with the upper connector 181 and one lower portion (not shown). It is preferable that the left and right positioning pins 20 of the lower coupling body 182 are disposed above the vertical joint bolt 19 disposed at the uppermost position in the lower coupling body 182, for example.

  Further, as shown in FIG. 3, the contact surface portion between the outer ring 161 on the steam inflow side and the outer ring 171 on the steam discharge side is provided with a concavo-convex portion 21 as a fitting portion for matching the mutual positional relationship during assembly. Is provided. Further, for example, a drain catcher 22 is provided on the inner peripheral side of the uneven portion 21. The concavo-convex portion 21 and the drain catcher 22 are provided so that the entire outer ring 161 on the steam inflow side and the outer ring 171 on the steam discharge side make one round in the circumferential direction.

  FIG. 4 is a partial plan view showing a contact surface of the lower connector 182 shown in FIG. 3 with the upper connector 181. The concavo-convex portion 21 includes, for example, a convex portion provided on the lower outer ring 165 on the steam inflow side and a concave portion provided on the lower outer ring 175 on the steam discharge side. In addition, the convex part is provided so that not only the lower outer ring 165 on the steam inflow side but also the entire outer ring 161 on the steam inflow side makes one round in the circumferential direction. Further, the recess is provided not only at the lower outer ring 175 on the steam discharge side but also around the entire outer ring 171 on the steam discharge side in the circumferential direction.

  In general, if the size of the recesses and the projections is the same, they interfere with each other during assembly and the assemblability deteriorates. Therefore, the sizes of the recesses in the radial and axial directions are made larger than the projections. . For this reason, a slight gap is formed between the concave portion and the convex portion. This gap is a substantial water flow path 23 of water generated by the steam that has entered from between the contact surfaces of the upper connecting body 181 and the lower connecting body 182.

  In the case of a device having such a moisture channel 23, if a conventional positioning pin having a constant diameter is arranged so as to extend in the radial direction, the moisture channel 23 may be blocked by the positioning pin. In the present embodiment, by providing a small-diameter portion having a smaller diameter than the other portions in at least a part of the positioning pin 20, it is possible to suppress such a blockage of the moisture channel 23 and suppress moisture retention. .

  5 is a partial cross-sectional view taken along line AA of the lower connector 182 shown in FIG. 6 and 7 are a BB line cross-sectional view and a CC line cross-sectional view of the lower connector 182 shown in FIG. 5, respectively.

  As shown in FIG. 5, the lower outer ring 175 on the steam discharge side is provided with, for example, a moisture channel 23 formed of a concave portion constituting one of the concave and convex portions 21 in the circumferential direction (the vertical direction in the drawing). In addition, a positioning pin hole 24 is provided in the lower outer ring 175 on the steam discharge side so as to be orthogonal to the moisture channel 23.

  Here, the positioning pin hole portion 24 provided in the lower outer ring 175 on the steam discharge side is formed as a concave groove that covers substantially half of the positioning pin 20 and is provided in the lower outer ring 165 on the steam inflow side. By combining with the positioning pin hole 24 that is a concave groove, a complete positioning pin hole 24 that covers the entire positioning pin 20 is formed.

  The positioning pin hole 24 has a constant diameter in the longitudinal direction as in the prior art. The diameter of the positioning pin hole 24 is normally 16 to 25 mm. The positioning pin 20 is fixed to the positioning pin hole 24 so as to be inserted from the outer peripheral side. The positioning pin 20 has, for example, a small diameter portion 201 at the center and a pair of large diameter portions 202 on both sides thereof.

  According to the positioning pin 20 having the small diameter part 201, moisture can be passed around the small diameter part 201 as shown in FIG. In addition, as shown in FIG. 7, by making the size of the large diameter portion 202 at both ends of the positioning pin 20 the same as the size of the positioning pin hole 24, the positioning effect during assembly, which is the original effect, is achieved. Can also be obtained.

  As the shape of the small-diameter portion 201, for example, as shown in FIG. 5, a reduced diameter portion that gradually decreases in diameter toward the central portion on both sides, and a constant diameter portion having a constant diameter provided between these reduced diameter portions. The thing which has these. The inclination angle of the reduced diameter portion can be appropriately set so as to facilitate processing with a tool.

  It suffices that at least a part of the length and position of the small-diameter portion 201 overlaps the moisture channel 23. According to such a thing, the water | moisture content of the water flow path 23 can be passed through the circumference | surroundings, and a residence of a water | moisture content can be suppressed. The small-diameter portion 201 preferably overlaps the moisture channel 23 in a range of 10% or more and more preferably in a range of 30% or more in the range of the moisture channel 23 in the width direction (left and right direction in FIG. 5). Preferably, it overlaps in the range of 50% or more. If the length of the small-diameter portion 201 is excessively large, the positioning function of the positioning pin 20 is impaired and the strength of the positioning pin 20 is reduced. Therefore, the length of the small-diameter portion 201 is approximately the same as the width of the moisture channel 23. Is preferred.

  The diameter of the small diameter part 201 is not necessarily limited as long as it is smaller than the diameter of the positioning pin hole 24. If the diameter of the small-diameter portion 201 is smaller than the diameter of the positioning pin hole portion 24, the moisture in the moisture channel 23 is allowed to pass therethrough so that moisture retention can be suppressed. The diameter of the small diameter portion 201 is preferably the smallest diameter portion, for example, a constant diameter portion, and the distance between the outer surface of the small diameter portion 201 and the inner surface of the positioning pin hole 24 is preferably 0.5 mm or more. What becomes the above is preferable. In addition, the diameter of the small diameter portion 201 is not necessarily limited as long as the strength of the small diameter portion 201 can be secured, but is the smallest diameter portion, for example, a constant diameter portion, between the outer surface of the small diameter portion 201 and the inner surface of the positioning pin hole portion 24. The distance is preferably 4 mm or less, and the distance is preferably 3 mm or less.

  In addition, the cross-sectional shape of the small diameter part 201 is not necessarily limited to the circular shape as shown in FIG. That is, the small diameter portion 201 is only required to form a gap of 0.5 mm or more, more preferably 1 mm or more between the inner surface of the positioning pin hole portion 24 and to allow moisture to pass therethrough. The distance between the outer surface of 201 and the inner surface of the positioning pin hole 24 is not necessarily constant in the circumferential direction.

  Further, the positioning pins 20 are not necessarily limited to those having a uniform cross-sectional structure. For example, the positioning pin 20 may have a cylindrical shape having an axially extending hole portion into which a tool for removing the positioning pin hole 24 is inserted after the positioning pin 20 is inserted into the positioning pin hole portion 24.

  Note that the positioning pin 20 having the small diameter portion 201 may be disposed on at least one of the left and right sides and the upper and lower sides of the nozzle diaphragm connector 18. In general, the moisture channel 23 is formed so as to make one round of the entire nozzle diaphragm connector 18, and there is a possibility that moisture is present in any part due to the inflow of steam. By using the positioning pin 20 having the small-diameter portion 201 on the upper part of the nozzle diaphragm connector 18 and at least one of the left and right sides, the retention of moisture in the moisture channel 23 can be suppressed.

  It is preferable that the positioning pins 20 having the small-diameter portions 201 are arranged one by one on the left and right in the vicinity of the contact surface of the lower connecting body 182 with the upper connecting body 181. In the moisture channel 23 of the lower coupling body 182, moisture generated by the vapor that has entered from the contact surface between the upper coupling body 181 and the lower coupling body 182 tends to stay. Therefore, the retention of moisture can be effectively suppressed by arranging the positioning pin 20 having the small diameter portion 201 in such a portion. In this case, the positioning pin 20 having the small-diameter portion 201 may be disposed in other portions, or the positioning pin 20 not having the small-diameter portion 201 may be disposed.

FIG. 8 is a plan view of the lower connector 182 shown in FIG.
A lower portion of the lower connecting body 182 is provided with a moisture discharge hole 25 that connects the moisture channel 23 and the outer peripheral portion and discharges the moisture in the moisture channel 23 to the outside. Usually, the vertical part passing through the center part of the lower coupling body 182 at the lower part of the lower coupling body 182 is provided with a lifting hole 26 for taking the center of gravity. In order to avoid such a lifting hole 26, it is preferable that one is provided on each of the left and right sides of the lifting hole 26. In particular, the lifting hole 26 is disposed at a position closest to the lifting hole 26. It is preferable that it is provided between the vertical joint bolt 19.

  By providing the moisture discharge hole 25 in the lower part as described above, the moisture generated by the vapor that has entered from the vicinity of the contact surface between the upper coupling body 181 and the lower coupling body 182 The pair of moisture discharge holes 25 can be efficiently discharged to the outside.

9 is a partial cross-sectional view taken along the line DD of the lower connector 182 shown in FIG.
As shown in FIG. 9, it is preferable that the entire moisture discharge hole 25 is provided inside a lower outer ring 175 on the steam discharge side having a recess that constitutes one of the uneven portions 21. Specifically, it is preferable that the whole is provided so as to cut out a part of the lower outer ring 175 on the steam discharge side having a concave portion constituting one of the concave and convex portions 21.

  For example, when the moisture discharge hole 25 is divided in half into a lower outer ring 165 on the steam inflow side and a lower outer ring 175 on the steam discharge side to form a concave groove and the whole is formed by combining the two, The contact area between the lower outer ring 165 on the side and the lower outer ring 175 on the steam discharge side decreases. Providing the entire moisture discharge hole 25 inside one is preferable because a contact area between the lower outer ring 165 on the steam inflow side and the lower outer ring 175 on the steam discharge side can be secured.

  The diameter of the moisture discharge hole 25 is not necessarily limited as long as the moisture in the moisture channel 23 can be effectively discharged, but is preferably 8 mm or more, more preferably 10 mm or more. Moreover, since the surrounding thickness will become thin when the diameter of the water | moisture-content discharge hole 25 becomes large too much, the diameter of the grade which can ensure the surrounding thickness is preferable. That is, the thickness of the lower outer ring 175 on the steam discharge side disposed between the lower outer ring 165 on the steam inflow side and the moisture discharge hole 25, and the lifting hole 26 and the moisture discharge hole 25 as shown in FIG. The thickness of the lower outer ring 175 on the steam discharge side in between, the thickness of the lower outer ring 175 on the steam discharge side between the hole for the vertical joint bolt 19 and the moisture discharge hole 25 as shown in FIG. Then, it is preferable to adjust the diameter of the moisture discharge hole 25.

  The position of the moisture discharge hole 25 is not necessarily limited as long as the moisture in the moisture channel 23 can be effectively discharged, but the position is close to the contact surface between the lower outer ring 165 on the steam inflow side and the lower outer ring 175 on the steam discharge side. The thickness of the lower outer ring 175 on the steam discharge side disposed between the lower outer ring 165 on the steam inflow side and the moisture discharge hole 25 is reduced. Therefore, it is preferable to set the position so as to ensure the thickness.

  The moisture discharge hole 25 is preferably provided entirely inside the recess having one of the concave and convex portions 21 as described above. For example, the lower outer ring 165 on the steam inflow side and the steam discharge side are provided, for example. The whole may be formed by dividing each of the contact surfaces with the lower outer ring 175 in half to form a concave groove and combining the two. In such a case, although the contact area between the lower outer ring 165 on the steam inflow side and the lower outer ring 175 on the steam discharge side is reduced, the moisture in the moisture channel 23 can be effectively discharged.

  Further, instead of providing the moisture discharge hole 25, or while providing the moisture discharge hole 25, a lifting hole portion 26 is formed so as to connect the moisture channel 23 and the outer peripheral portion of the lower connector 182. The hole 26 may be used as the moisture discharge hole 25. The moisture discharge hole 25 including the lifting hole 26 can effectively discharge the moisture in the moisture channel 23 to the outside in the same manner as the moisture discharge hole 25 having only a discharge function.

  As mentioned above, although some embodiment of invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Steam turbine, 11 ... Main steam pipe, 12 ... Exhaust flow path, 13 ... Casing, 14 ... Moving blade, 15 ... Turbine rotor, 16 ... Nozzle diaphragm stage (steam inflow side), 17 ... Nozzle diaphragm stage (steam discharge) 18) Nozzle diaphragm connector, 19 ... Vertical joint bolt, 20 ... Positioning pin, 21 ... Concavity and convexity, 22 ... Drain catcher, 23 ... Water passage, 24 ... Positioning pin hole, 25 ... Water discharge hole , 26 ... Lifting holes, 161 ... Outer ring, 162 ... Nozzle plate, 163 ... Inner ring, 164 ... Upper outer ring, 165 ... Lower outer ring, 167 ... Upper inner ring, 168 ... Lower inner ring, 171 ... Outer ring, 172 ... Nozzle plate, 174 ... Upper outer ring, 175 ... Lower outer ring, 178 ... Lower inner ring, 181 ... Upper connecting body, 182 ... Lower connecting body, 201 ... Small diameter part, 202 ... Large diameter part

Claims (9)

A plurality of nozzle diaphragm paragraphs connected to each other;
A moisture channel formed to extend in a circumferential direction between adjacent nozzle diaphragm stages of the plurality of nozzle diaphragm stages;
A positioning pin that is arranged so as to extend in a radial direction between adjacent nozzle diaphragm stages of the plurality of nozzle diaphragm stages, and has a small-diameter portion that is smaller in diameter than other parts in a portion overlapping the moisture flow path;
A nozzle-diaphragm linking body, comprising: a moisture discharge hole that connects the moisture channel and outer peripheral portions of the plurality of nozzle diaphragm stages, and drains the moisture in the moisture channel to the outside.   2. The nozzle diaphragm connection according to claim 1, wherein the nozzle diaphragm connection body includes an upper connection body and a lower connection body, and the positioning pins are arranged one on each of the left and right sides of the lower connection body. body.   The lower coupling body includes vertical joint bolts that fix the plurality of nozzle diaphragm stages to each other, and the positioning pins arranged on the left and right of the lower coupling body are both of the vertical coupling bolts of the lower coupling body. The nozzle-diaphragm coupling body according to claim 2, wherein the nozzle diaphragm coupling body is disposed above the uppermost one.   The said water discharge hole is provided in the lower part of the said nozzle-diaphragm coupling body, and one each is provided in the right and left of the perpendicular line which passes along the center part of the said nozzle-diaphragm coupling body. The nozzle-diaphragm coupling body according to any one of the above.   5. The nozzle diaphragm coupling body according to claim 1, wherein the moisture discharge hole is entirely provided inside a nozzle diaphragm stage of any one of the plurality of nozzle diaphragm stages. 6.   The nozzle diaphragm coupling body is a lower part of the nozzle diaphragm coupling body, and has a lifting hole portion on a vertical line passing through a central portion of the nozzle diaphragm coupling body, and the lifting hole portion has the moisture discharge hole. The nozzle-diaphragm coupling body according to any one of claims 1 to 5, wherein the nozzle-diaphragm coupling body is also used.   The moisture channel is a gap between concave and convex portions having a fitting structure of a concave portion formed in one of the nozzle diaphragm paragraphs adjacent to the plurality of nozzle diaphragm paragraphs and a convex portion formed in the other. The nozzle-diaphragm coupling body according to any one of claims 1 to 6.   The nozzle diaphragm connector according to claim 7, wherein each of the plurality of nozzle diaphragm stages includes an outer ring, a nozzle plate, and an inner ring, and the uneven portion is formed between the outer rings. A steam turbine having a casing and a nozzle diaphragm connector disposed in the casing,
A steam turbine according to any one of claims 1 to 8, wherein the nozzle diaphragm connector is a nozzle diaphragm connector.

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