JP2007120321A - Steam turbine nozzle and steam turbine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steam turbine nozzle having a compact shape and high durability. <P>SOLUTION: This steam turbine nozzle 1 has a circular outer ring 2 having a guide groove 11 on the inner diameter side, a plurality of nozzles 3 and a plurality of circular arc-shaped packing rings 4 inserted into a groove 41 of a nozzle implanting part 33 of the nozzles 3. The nozzles 3 have a nozzle inserting part 31 inserted into the guide groove 11 of the outer ring 2, a nozzle plate 32 having one end connected to the nozzle inserting part 31 or integrally molded with the nozzle inserting part and the nozzle implanting part 33 connected to the other end of this nozzle plate 32 or integrally molded with the nozzle plate and arranging the groove 41 on the inner diameter side. A joint 51 between the nozzles 3 and a joint 52 between the packing rings 4 are arranged by being mutually dislocated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a highly durable steam turbine nozzle and a steam turbine.

Conventionally, steam turbine nozzles have mainly been in the form of a combination of an outer ring, a nozzle plate, an inner ring, and a packing ring. However, in order to make the steam turbine nozzle compact, those having no inner ring have been proposed. In a steam turbine nozzle of a type without an inner ring, an invention has been made in which a packing ring is provided on the base side (rotor side) of the nozzle. (For example, Patent Documents 1 to 3).
JP-A-7-324601 JP-A-11-200801 JP 2000-97350 A

  A steam turbine nozzle having a shape without an inner ring is shown in FIG. In FIG. 13, the steam turbine nozzle 1 without such an inner ring has no strength member (inner ring) for tightening the base side of the nozzle, and therefore has low rigidity and low durability. Even if the packing ring is arranged on the base side of the nozzle, as shown in FIG. 13, the joint 51 between the nozzles 3 and the joint 52 between the packing rings 4 are arranged to face each other. Therefore, its strength was not sufficient.

  The present invention has been made in consideration of such points, and an object thereof is to provide a steam turbine nozzle having a compact shape and high durability.

  The present invention includes a circular outer ring having a guide groove on the inner diameter side, a nozzle insertion portion that is inserted into the guide groove of the outer ring, and one end that is connected to the nozzle insertion portion or integrally formed with the nozzle insertion portion. A plurality of nozzles having a nozzle plate connected to the other end of the nozzle plate or integrally formed with the nozzle plate and provided with a groove on the inner diameter side, and inserted in the groove of the nozzle implantation portion of the nozzle. A steam turbine nozzle comprising a plurality of arc-shaped packing rings to be attached, wherein a joint between the nozzles and a joint between the packing rings are arranged so as to be shifted from each other.

  The present invention provides a circular outer ring that is separable into at least two or more parts and has a guide groove on the inner diameter side, a nozzle insertion part that is inserted into the guide groove of the outer ring, and the nozzle insertion part Or a nozzle plate having one end integrally formed with the nozzle insertion portion, and a nozzle implantation portion connected to the other end of the nozzle plate or integrally formed with the nozzle plate and provided with a groove on the inner diameter side. A plurality of nozzles and a plurality of arc-shaped packing rings inserted into the grooves of the nozzle implantation portion of the nozzle, and a joint between the outer ring portions is a joint between nozzles and a joint between packing rings The steam turbine nozzle is characterized in that the joints between the nozzles arranged corresponding to the eyes and not corresponding to the joints between the parts of the outer ring are displaced from the joints between the packing rings.

  The present invention is a circular outer ring having a guide groove on the inner diameter side, a nozzle insertion part that is inserted into the guide groove of the outer ring, and a nozzle insertion part that is connected to or integrally formed with the nozzle insertion part. A plurality of nozzles having a nozzle plate having one end, a nozzle plate connected to the other end of the nozzle plate or integrally formed with the nozzle plate, and provided with a groove on the inner diameter side; and inserted into a groove in the nozzle implantation portion of the nozzle. A plurality of arc-shaped packing rings to be worn, the nozzle implantation portion of the nozzle forms a groove of the nozzle implantation portion, and has a nozzle convex portion that fits into the packing ring. The groove ring depth T of the nozzle implanting portion has a packing ring recess fitted to the nozzle projection of the nozzle implanting portion and the packing ring projection arranged on the nozzle plate side of the packing ring recess. The ratio (T2 / T1) to the height T1 of the nozzle implantation portion is 0.85 or less, and the height of the convex portion provided on the packing ring disposed on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion The steam turbine nozzle is characterized in that a ratio (T4 / T1) of T4 to the height T1 of the nozzle implantation portion is 0.3 or more.

  The present invention relates to the height T4 of the convex portion provided on the packing ring disposed on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion with respect to the depth T5 of the groove on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion. The steam turbine nozzle is characterized in that the ratio (T4 / T5) is 0.8 or more.

  The present invention includes a groove depth T5 on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion, and a height T4 of the convex portion provided on the packing ring disposed on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion. The steam turbine nozzle is characterized in that the difference (T5−T4) is 2 mm or more.

  The present invention is the steam turbine nozzle, wherein the packing ring has a ratio (T7 / T6) of the width T7 of the packing ring convex portion to the width T6 of the nozzle implantation portion being 0.5 or more.

  The present invention is the steam turbine nozzle, wherein a ratio (T8 / T7) of the width T8 of the packing ring concave portion to the width T7 of the packing ring convex portion is 0.7 or more.

  The present invention is a steam turbine nozzle in which a coil spring is disposed between a packing ring and a nozzle implantation portion of a nozzle.

  The present invention is a steam turbine nozzle characterized in that a caulking member having a linear expansion coefficient larger than that of each material of the outer ring, the nozzle plate, and the packing ring is provided at the joint of the packing ring.

  The present invention is a steam turbine nozzle characterized in that an anti-slip coking member is disposed between a packing ring and a nozzle implantation portion of the nozzle.

  The present invention is a steam turbine using the steam turbine nozzle described above.

  ADVANTAGE OF THE INVENTION According to this invention, while having a compact shape, a highly durable steam turbine nozzle can be provided.

First Embodiment Hereinafter, a first embodiment of a steam turbine nozzle 1 according to the present invention will be described with reference to the drawings. Here, FIG. 1 to FIG. 3 are diagrams showing a first embodiment of the present invention.

  As shown in FIGS. 1 and 2, in the steam turbine nozzle 1 of the present embodiment, the outer ring 2 has an upper half turbine nozzle part 2a and a lower half turbine nozzle part through a joint 53 between the parts 2a and 2b. 2b, having a guide groove 11 on the inner diameter side thereof, a plurality of nozzles 3 inserted into the guide groove 11, and a plurality of arc-shaped packing rings inserted into the nozzle 3 With 4

  As shown in FIG. 2, each nozzle 3 includes a nozzle insertion portion 31 that is inserted into the guide groove 11 of the outer ring 2, and a nozzle 32 that is connected to or integrally formed with the nozzle insertion portion 31. It has a plate 32 and a nozzle implantation portion 33 which is connected or integrally formed with the other end 32b of the nozzle plate 32 and has a groove 41 on its inner diameter side. In addition, integral molding here means what was formed by cutting collectively by NC processing etc. from one piece of material, and formed by mechanical connection, such as welding, after processing for every part. It is not a thing.

  Further, as shown in FIG. 2, the packing ring 4 is mounted in the groove 41 of the nozzle implantation portion 33 of the nozzle 3. In the steam turbine nozzle 1 shown in FIGS. 1 and 2, six arc-shaped packing rings 4 are arranged. In order to facilitate insertion into the groove 41 of the nozzle implantation portion 33 of the nozzle 3, It is preferable to use 4 to 8 arc-shaped packing rings 4.

  As shown in FIGS. 1 and 2, a joint 53 between the upper half turbine nozzle portion 2 a and the lower half turbine nozzle portion 2 b (hereinafter, a joint between the portions 2 a and 2 b of the outer ring 2) is: The joint 51 between the nozzles 3 that is arranged corresponding to the joint 51 between the nozzles 3 and the joint 52 between the packing rings 4 and does not correspond to the joint 53 between the portions 2 a and 2 b of the outer ring 2 is the packing ring 4. It is arranged so as to be shifted from the joint 52 between them.

  Next, the operation of the present embodiment having such a configuration will be described.

  As shown in FIGS. 1 and 2, the joint 51 between the nozzles 3 that does not correspond to the joint 53 between the portions 2 a and 2 b of the outer ring 2 and the joint 52 between the packing rings 4 are arranged so as to be shifted from each other. ing. That is, the packing ring 4 is disposed across the center direction of the outer ring 2 of the joint 51 between the nozzles 3 that does not correspond to the joint 53 between the portions 2 a and 2 b of the outer ring 2.

  For this reason, even if the forces F1 and F2 indicated by the arrows in FIG. 1 are applied to the nozzle 3, the movement of the nozzle 3 is suppressed by the packing ring 4 disposed across the center direction of the outer ring 2, and the nozzle 3 There is no deviation in the direction of the forces F1 and F2. For this reason, the durability of the steam turbine nozzle 1 can be improved.

  Next, a modification of the present embodiment will be described with reference to FIG.

  As shown in the modification of the present embodiment shown in FIG. 3, in the steam turbine nozzle 1, the joint 51 between the nozzles 3 and the joint 52 between the packing rings 4 are shifted from each other. It may be arranged.

  In FIG. 3, the other configuration is substantially the same as the embodiment shown in FIGS. In FIG. 3, the same parts as those in the embodiment shown in FIG. 1 and FIG.

  As described above, the joints 51 between all the nozzles 3 are arranged so as to be displaced from the joints 52 between the packing rings 4, whereby the durability of the steam turbine nozzle 1 can be further improved.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. 4 to 7, the same parts as those of the first embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the second embodiment shown in FIGS. 4 to 7, the nozzle 3 and the packing ring 4 have specific configurations, and the other configurations are substantially the same as those of the first embodiment shown in FIGS. 1 to 3. Are the same.

  The second embodiment shown in FIGS. 4 to 7 is separable into an upper half turbine nozzle part 2a and a lower half turbine nozzle part 2b through a joint 53 between the parts 2a and 2b of the outer ring 2. And has a guide groove 11 on the inner diameter side thereof, and includes a plurality of nozzles 3 inserted into the guide groove 11 and a plurality of arc-shaped packing rings 4 inserted into the nozzle 3 (see FIG. 1 to 3).

  Among these, the plurality of nozzles 3 are connected or integrally formed with the nozzle insertion portion 31, the nozzle plate 32 having one end 32 a connected or integrally formed with the nozzle insertion portion 31, and the other end 32 b of the nozzle plate 32, It has the nozzle implantation part 33 which provided the groove | channel 41 in the internal diameter side (refer FIG. 2).

  FIG. 4 shows a partial cross section of the steam turbine nozzle 1 in the present embodiment. As shown in FIG. 4, the nozzle implanting portion 33 of the nozzle 3 forms a groove 41 of the nozzle implanting portion 33 and has a nozzle convex portion 34 that fits with the packing ring 4. Further, the packing ring 4 includes a packing ring concave portion 42 that fits with the nozzle convex portion 34 of the nozzle implantation portion 33 of the nozzle 3, and a packing ring convex portion 43 that is disposed on the nozzle plate 32 side of the packing ring concave portion 42. Have.

  Here, the ratio (T2 / T1) of the depth T2 of the groove 41 of the nozzle implantation part 33 to the height T1 of the nozzle implantation part 33 is 0.85 or less. Further, the ratio (T4 / T1) of the height T4 of the packing ring convex portion 43 of the packing ring 4 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implanting portion 33 to the height T1 of the nozzle implanting portion 33. Is 0.3 or more (see FIG. 4).

  Further, the height T4 of the packing ring convex portion 43 of the packing ring 4 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implant portion 33 is closer to the nozzle plate 32 than the nozzle convex portion 34 of the nozzle implant portion 33. The ratio (T4 / T5) to the depth T5 of the groove 41 is 0.8 or more (see FIG. 4).

  Further, as shown in FIG. 7, the packing ring 4 is provided with a coil spring accommodating portion 6, and one end 5a is connected or simply placed in the coil spring accommodating portion 6 and the other end 5b is implanted in the nozzle. The coil spring 5 connected to or in contact with the nozzle implantation portion upper wall 33a of the portion 33 may be housed and disposed.

  Next, the operation of the present embodiment having such a configuration will be described.

  When the steam turbine blade (not shown) becomes long, the centrifugal force applied to the steam turbine blade increases, and the steam turbine blade, particularly the implanted portion, is overloaded. For this reason, it is necessary to shorten the steam turbine rotor blade, but the length of the steam turbine rotor blade generally corresponds to the total height of the nozzle 3 and the packing ring 4.

  For this reason, in order to shorten the length of the steam turbine rotor blade, the total height of the nozzle 3 and the packing ring 4 may be reduced, and reducing the height T1 of the nozzle implantation portion 33 may reduce the length of the steam turbine blade. This is useful for reducing the load on the rotor blades.

  Further, in order to improve the durability of the steam turbine nozzle 1, it is preferable to increase the cross-sectional area of the packing ring 4 inserted into the nozzle implantation portion 33 of the nozzle 3 so as to increase the cross-sectional second moment. For this reason, it is preferable to make the groove 41 formed in the nozzle implantation part 33 into which the packing ring 4 is inserted as large as possible.

  On the other hand, if the thickness T3 of the nozzle implantation portion upper wall 33a between the nozzle plate 32 and the groove 41 of the nozzle implantation portion 33 becomes too thin, as shown in FIG. 5B, the nozzle implantation portion upper wall 33a. Is deformed, and the same degree of shear stress is generated in the A portion and the B portion of the nozzle implantation portion 33. For this reason, durability of the nozzle implantation part 33 will fall remarkably.

  Here, when the ratio (T2 / T1) of the depth T2 of the groove 41 of the nozzle implantation portion 33 to the height T1 of the nozzle implantation portion 33 is larger than 0.85, the deformation as shown in FIG. Resulting in. On the other hand, according to the present invention, the ratio (T2 / T1) of the depth T2 of the groove 41 of the nozzle implantation portion 33 of the steam turbine nozzle 1 to the height T1 of the nozzle implantation portion 33 is 0.85 or less. Therefore, as shown in FIG. 5A, the normal nozzle implantation portion upper wall 33a can be maintained.

  Moreover, if the height T4 of the convex portion of the packing ring 4 disposed on the nozzle plate 32 side of the nozzle convex portion 34 of the nozzle implantation portion 33 becomes too small, as shown in FIG. The turbine nozzle 1 is greatly deformed.

  The ratio (T4 / T1) of the height T4 of the packing ring 4 disposed on the nozzle plate 32 side of the nozzle convex portion 34 of the nozzle implanted portion 33 to the height T1 of the nozzle implanted portion 33 is from 0.3. If it becomes small, as shown to Fig.6 (a), the steam turbine nozzle 1 will deform | transform greatly.

  On the other hand, according to the present invention, the ratio of the height T4 of the packing ring 4 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33 to the height T1 of the nozzle implantation portion 33 (T4 / Since T1) is 0.3 or more, the deformation amount of the steam turbine nozzle 1 can be kept small as shown in FIG. 6B.

  Further, the depth T5 of the groove 41 on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33 at the height T4 of the packing ring 4 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33. The ratio (T4 / T5) to is 0.8 or more. For this reason, since the cross-sectional area of the cross section of the packing ring 4 inserted in the nozzle implantation part 33 becomes large and the cross-sectional secondary moment of the packing ring 4 can be enlarged, the durability of the packing ring 4 is improved. Can do.

  In addition, the depth T5 of the groove 41 on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33 at the height T4 of the packing ring 4 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33. The depth T5 of the groove 41 on the nozzle plate 32 side with respect to the nozzle convex portion 34 of the nozzle implantation portion 33 and the nozzle convex portion 34 of the nozzle implantation portion 33 instead of setting the ratio (T4 / T5) to 0.8 or more. Even if the difference (T5−T4) from the height T4 of the packing ring 4 arranged on the nozzle plate 32 side is 2 mm or more, the same effect can be obtained.

  Further, as shown in FIG. 7, the coil ring housing 6 is provided in the packing ring 4 and the coil spring 5 is provided to prevent rubbing with a rotor (not shown) arranged on the inner diameter side of the steam turbine nozzle 1. You can also

  Further, the coil spring 5 can be attached without a large space such as a leaf spring. For this reason, the height T4 of the packing ring convex portion 43 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33 and the groove 41 on the nozzle plate 32 side of the nozzle convex portion 34 of the nozzle implantation portion 33 are arranged. The ratio (T4 / T5) to the depth T5 can be adjusted to be 0.8 or more. Further, the depth T5 of the groove 41 on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33 and the height of the packing ring convex portion 43 disposed on the nozzle plate 32 side from the nozzle convex portion 34 of the nozzle implantation portion 33. The difference (T5−T4) from the height T4 can be adjusted to be 2 mm or more.

  In addition, when providing the coil spring 5 and the coil spring accommodating part 6 so that an elastic force may work between the nozzle 3 and the packing ring 4 with good balance, it is preferable to provide at least two places for each packing ring 4.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. In addition, in each figure, the same code | symbol is attached | subjected to the same part as 2nd Embodiment shown in FIG. 4 thru | or FIG. 7, and detailed description is abbreviate | omitted. In the third embodiment shown in FIGS. 8 and 9, the ratio of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33 is 0.5 or more, and the width T8 of the packing ring concave portion 42 The packing ring 4 having a ratio of the packing ring convex portion 43 to the width T7 of 0.7 or more is used, and the others are substantially the same as those of the second embodiment shown in FIGS.

  By increasing the cross-sectional area of the cross section of the packing ring 4 disposed in the nozzle implantation portion 33, the secondary moment of the cross section of the packing ring 4 can be increased, so that the durability of the packing ring 4 can be improved. it can.

  Next, the relationship between the cross-sectional shape of the packing ring 4 and the rigidity will be described.

  The rigidity of the packing ring 4 varies depending on the secondary moment of the section of the packing ring 4. Further, the cross-sectional secondary moment varies depending on the width T7 of the packing ring convex portion 43, the width T6 of the nozzle implantation portion 33, and the width T8 of the packing ring concave portion 42.

  FIG. 9 shows the relationship between the change in the ratio (T7 / T6) of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33 and the amount of change in the cross-sectional secondary moment, and the packing ring concave portion 42. The relationship between the change in the ratio (T8 / T7) of the width T8 to the width T7 of the packing ring convex portion 43 and the amount of change in the sectional moment of inertia is shown.

  As shown in FIG. 9, by increasing the ratio (T7 / T6) of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33, the cross-sectional secondary moment can be greatly changed. Thus, the rigidity of the packing ring 4 can be increased. On the other hand, even if the ratio (T8 / T7) of the width T8 of the packing ring concave portion 42 to the width T7 of the packing ring convex portion 43 is increased, the cross-sectional secondary moment does not change much. For this reason, the rigidity of the packing ring 4 does not change greatly.

  When the width T7 of the packing ring convex portion 43 is changed and the amount of deflection of the packing ring 4 is numerically calculated by simulation, the ratio of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33 (T7 / T6) 10 and the change in the amount of deflection of the packing ring 4 are as shown in FIG. For this reason, when the ratio (T7 / T6) of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33 is larger than 0.4, the amount of deflection of the packing ring 4 becomes 5 mm or less. Since it hardly changes, a robust and safe design can be performed.

  When the ratio (T7 / T6) of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33 is 0.4 or more, the deflection amount of the packing ring 4 is generally steam. The value is below the allowable value for the turbine to operate normally.

  In order to obtain a safe and highly reliable steam turbine nozzle 1, the ratio (T7 / T6) of the width T7 of the packing ring convex portion 43 to the width T6 of the nozzle implantation portion 33 should be 0.4 or more. Is preferred.

  In FIG. 8, when the width T8 of the packing ring recess 42 is reduced and the step T9 between the packing ring protrusion 43 and the packing ring recess 42 is increased, the packing ring recess 42 in which the packing ring 4 is fitted to the nozzle implantation portion 33 is obtained. The moment generated by the pressure increases, and the stress generated in the portion C of the packing ring 4 increases.

  Therefore, the ratio (T8 / T7) of the width T8 of the packing ring concave portion 42 to the width T7 of the packing ring convex portion 43 is as small as possible so that the step T9 between the packing ring convex portion 43 and the packing ring concave portion 42 becomes small. A larger packing ring 4 with higher durability can be obtained.

  When the numerical value is calculated by changing the width T8 of the packing ring concave portion 42 and simulating the stress applied to the C portion, the ratio (T8 / T7) of the width T8 of the packing ring concave portion 42 to the width T7 of the packing ring convex portion 43 is 0. When the value is smaller than .7, the stress in the portion C of the packing ring 4 generally exceeds the allowable stress value because the steam turbine (not shown) can operate normally. On the other hand, according to the present invention, the ratio (T8 / T7) of the width T8 of the packing ring concave portion 42 to the width T7 of the packing ring convex portion 43 is 0.7 or more. For this reason, it can prevent that the stress which generate | occur | produces in the C part of the packing ring 4 becomes large too much, and can operate | move a steam turbine normally.

Fourth Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. 11 and 12, the same parts as those of the first embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals, and detailed description thereof is omitted. In the fourth embodiment shown in FIG. 11, a caulking member 44 having a linear expansion coefficient larger than each material of the outer ring 2, the nozzle plate 32, and the packing ring 4 is provided at the joint 52 between the packing rings 4. An anti-shifting caulking member 45 is disposed between the ring 4 and the nozzle implantation portion 33 of the nozzle 3 or a combination of the two, and the rest is substantially the same as in the first embodiment shown in FIGS. It is.

  When the steam turbine nozzle 1 is used, the temperature rises. For this reason, each structural member of the steam turbine nozzle 1 may thermally expand, and a gap may be generated in the joint 52 between the packing rings 4.

  For this reason, as shown in FIG. 11, by providing a caulking member 44 having a larger linear expansion coefficient than the materials of the outer ring 2, the nozzle plate 32 and the packing ring 4 at the joint 52 between the packing rings 4, the steam turbine nozzle Even if the temperature of 1 increases, the gap generated between the packing rings 4 can be kept covered by the caulking member 44. For this reason, the durability of the steam turbine nozzle 1 can be improved.

  Further, when the steam turbine nozzle 1 is used and the temperature rises, a gap is generated between the nozzle 3 and the packing ring 4, and the packing ring 4 rotates in the circumferential direction due to vibration caused by driving the steam turbine. There are things to do.

  In this way, when the packing ring 4 rotates in the circumferential direction, the joint 51 between the nozzles 3 that does not correspond to the joint 53 between the portions 2 a and 2 b of the outer ring 2 coincides with the joint 52 between the packing rings 4. Or the joints 51 between the nozzles 3 and the joints 52 between the packing rings 4 may coincide with each other.

  On the other hand, according to the present invention, as shown in FIG. 12, by disposing the misalignment preventing caulking member 45 between the packing ring 4 and the nozzle implantation portion 33 of the nozzle 3, the packing ring 4 is surrounded. The joint 51 between the nozzles 3 that does not correspond to the joint 53 between the portions 2 a and 2 b of the outer ring 2 does not coincide with the joint 52 between the packing rings 4. Further, the joint 51 between the nozzles 3 and the joint 52 between the packing rings 4 do not coincide with each other.

  By the way, by manufacturing the steam turbine using the steam turbine nozzle 1 shown in each of the above-described embodiments, it is possible to obtain a steam turbine having a small moving blade with a small size and high durability.

1 is a schematic diagram showing a first embodiment of a steam turbine nozzle according to the present invention. The block diagram which shows 1st Embodiment of the steam turbine nozzle by this invention. Schematic which shows the modification of 1st Embodiment of the steam turbine nozzle by this invention. Sectional drawing which shows the ratio of each area | region in 2nd Embodiment of the steam turbine nozzle by this invention. Sectional drawing which shows the mode of a deformation | transformation of the nozzle implantation part of a nozzle. Sectional drawing which shows the mode of a deformation | transformation of the flexibility of a nozzle and a packing ring. Sectional drawing which shows the coil spring in 2nd Embodiment of the steam turbine nozzle by this invention. Sectional drawing which shows the ratio of each area | region in 3rd Embodiment of the steam turbine nozzle by this invention. The graph which shows the change of the cross-sectional secondary moment which generate | occur | produces in the packing ring in 3rd Embodiment of the steam turbine nozzle by this invention. The graph which shows the change of the deflection amount with respect to T7 / T6 in 3rd Embodiment of the steam turbine nozzle by this invention. Schematic which shows 4th Embodiment of the steam turbine nozzle by this invention. Sectional drawing which shows 4th Embodiment of the steam turbine nozzle by this invention. Schematic which shows the conventional steam turbine nozzle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steam turbine nozzle 2 Outer ring | wheel 2a, 2b Part 3 Nozzle 4 Packing ring 5 Coil spring 11 Guide groove 31 Nozzle insertion part 32 Nozzle plate 33 Nozzle implantation part 34 Nozzle convex part 41 Groove 42 Packing ring concave part 43 Packing ring convex part 44 Caking member 45 Misalignment preventing caulking member 51 Joint 52 between nozzles 52 Joint 53 between packing rings 53 Joint between outer ring parts

Claims (11)

A circular outer ring having a guide groove on the inner diameter side;
A nozzle insertion portion to be inserted into the guide groove of the outer ring, a nozzle plate having one end connected to the nozzle insertion portion or integrally formed with the nozzle insertion portion, and connected to the other end of the nozzle plate or the nozzle plate A plurality of nozzles integrally formed with a nozzle implantation portion provided with a groove on the inner diameter side;
A plurality of arc-shaped packing rings inserted into the grooves of the nozzle implantation portion of the nozzle,
The steam turbine nozzle according to claim 1, wherein the joint between the nozzles and the joint between the packing rings are arranged so as to be shifted from each other. A circular outer ring that is separable into at least two parts and has a guide groove on the inner diameter side;
A nozzle insertion portion that is inserted into the guide groove of the outer ring, a nozzle plate that is connected to the nozzle insertion portion or formed integrally with the nozzle insertion portion, and is connected to the other end of the nozzle plate or A plurality of nozzles integrally formed with this nozzle plate and having a nozzle implantation portion provided with a groove on the inner diameter side;
A plurality of arc-shaped packing rings inserted into the grooves of the nozzle implantation portion of the nozzle,
The joint between the parts of the outer ring is arranged corresponding to the joint between the nozzles and the joint between the packing rings,
A steam turbine nozzle, wherein the joints between the nozzles not corresponding to the joints between the outer ring portions are arranged so as to be shifted from the joints between the packing rings. A circular outer ring having a guide groove on the inner diameter side;
Nozzle insertion portion to be inserted into the guide groove of the outer ring, a nozzle plate having one end connected to the nozzle insertion portion or integrally formed with the nozzle insertion portion, and connected to the other end of the nozzle plate or nozzle A plurality of nozzles integrally formed with a plate and having a nozzle implantation portion provided with a groove on the inner diameter side;
A plurality of arc-shaped packing rings inserted into the groove of the nozzle implantation portion of the nozzle,
The nozzle implantation part of the nozzle has a nozzle convex part that fits with the packing ring while forming a groove of the nozzle implantation part,
The packing ring has a packing ring concave portion that fits with the nozzle convex portion of the nozzle implantation portion of the nozzle, and a packing ring convex portion arranged on the nozzle plate side of the packing ring concave portion,
A packing in which the ratio (T2 / T1) of the groove depth T2 of the nozzle implantation portion to the height T1 of the nozzle implantation portion is 0.85 or less, and is disposed closer to the nozzle plate than the nozzle convex portion of the nozzle implantation portion A steam turbine nozzle, wherein a ratio (T4 / T1) of a height T4 of a convex portion provided on the ring to a height T1 of a nozzle implantation portion is 0.3 or more.   The ratio of the height T4 of the convex portion provided on the packing ring arranged on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion to the depth T5 of the groove on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion (T4 / The steam turbine nozzle according to claim 3, wherein T5) is 0.8 or more.   Difference (T5) between the depth T5 of the groove on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion and the height T4 of the convex portion provided on the packing ring disposed on the nozzle plate side from the nozzle convex portion of the nozzle implantation portion -T4) is 2 mm or more, The steam turbine nozzle of Claim 3 characterized by the above-mentioned.   The steam turbine nozzle according to claim 3 or 4, wherein the packing ring has a ratio (T7 / T6) of the width T7 of the packing ring convex portion to the width T6 of the nozzle implantation portion being 0.5 or more.   The steam turbine nozzle according to claim 6, wherein the ratio (T8 / T7) of the width T8 of the packing ring concave portion to the width T7 of the packing ring convex portion is 0.7 or more.   The steam turbine nozzle according to any one of claims 1 to 7, wherein a coil spring is disposed between the packing ring and a nozzle implantation portion of the nozzle.   The steam turbine nozzle according to any one of claims 1 to 8, wherein a caulking member having a linear expansion coefficient larger than each material of the outer ring, the nozzle plate, and the packing ring is provided at a joint of the packing ring. .   The steam turbine nozzle according to any one of claims 1 to 9, wherein a shift preventing coking member is disposed between the packing ring and a nozzle implantation portion of the nozzle.   A steam turbine using the steam turbine nozzle according to claim 1.

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