JP6499478B2 - Steam generator, nuclear power plant, and seismic reinforcement method for steam generator - Google Patents

Description

  The present disclosure relates to a steam generator for generating steam by heat exchange with a fluid flowing in a heat transfer tube, a nuclear power plant including the steam generator, and a seismic reinforcement method for the steam generator.

In general, as a heat transfer tube structure of a steam generator, a structure in which a plurality of straight tube portions arranged in a vertical direction are connected to each other by a U-shaped bent portion is known. An assembly of a plurality of bent portions is usually referred to as a U-bend portion.
As an earthquake resistant structure in the U bend part, for example, Patent Document 1 discloses a structure in which a member holding a plurality of heat transfer tubes in the U bend part is fixed by a support member. Further, Patent Document 2 discloses a structure in which a heat transfer tube of a U bend portion is fixed to a container (body portion) of a steam generator via a support member.

  Furthermore, Patent Document 3 discloses a support structure for a U bend part that can improve the earthquake resistance of the U bend part and the resistance to flow vibration. Here, the fluid excitation vibration is vibration generated by the secondary cooling water flowing around the heat transfer tube of the U bend part or the primary cooling water flowing in the heat transfer pipe of the U bend part. Specifically, the steam generator includes a first support member provided so as to surround the U bend portion between the U bend portion and the tube group outer tube, a first support member, and the tube group outer tube. And a third support member for supporting the second support member.

US Pat. No. 6,772,732 US Pat. No. 5,692,557 JP 2013-011380 A

In recent years, since the demand for improving the earthquake resistance of steam generators is increasing, it is required to further improve the earthquake resistance of the steam generator. On the other hand, for the purpose of increasing the efficiency of the steam generator, the steam generator has been increased in size and the heat transfer tube has been reduced in diameter, and the weight of the steam generator tends to increase. Therefore, there is a concern that the shaking of the heat transfer tube will increase with respect to vibrations such as earthquakes. To reduce the weight of the steam generator, the heat transfer tube is made thinner, but from the viewpoint of the heat transfer tube shaking, the heat transfer tube rigidity may decrease due to the thinning of the heat transfer tube, and the heat transfer tube may be shaken. There is.
Therefore, a structure capable of realizing high seismic performance even for a steam generator corresponding to high efficiency is desired.

  In this regard, in the steam generator described in Patent Document 3, the first support member, the second support member, and the third support member have improved the earthquake resistance performance. However, recent requirements for the earthquake resistance performance of the steam generator have been improved. As a result, the development of steam generators that can further improve seismic performance is expected.

  In view of the above circumstances, at least one embodiment of the present invention aims to provide a steam generator and a nuclear power plant that can improve earthquake resistance in a bent portion of a heat transfer tube, and a method for earthquake strengthening of the steam generator. To do.

(1) A steam generator according to at least one embodiment of the present invention comprises:
A steam generator for generating steam by heat exchange with a fluid flowing in a heat transfer pipe,
A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bend located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes each having a portion;
A tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted;
A support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction orthogonal to a plane including the bent portion,
The plurality of heat transfer tubes such that a plurality of the bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and a plurality of the bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion pass are arranged according to a regular arrangement in a top view of the pipe support plate,
The regular arrangement includes an arrangement defect portion in which the heat transfer tubes do not exist in at least one row along the in-plane direction or the out-of-plane direction,
The support member is provided in at least a part of a space surrounded by the bent portions of a plurality of heat transfer tubes existing around the arrangement defect portion.

According to the configuration of (1) above, the plurality of through holes through which the first straight pipe portion and the second straight pipe portion pass are arranged according to a regular arrangement in a top view of the pipe support plate. It includes an arrangement defect portion in which the heat transfer tubes do not exist in at least one row along the inward or out-of-plane direction. That is, at least one row is missing in the regular arrangement defined by the through-hole through which the first straight pipe portion and the second straight pipe portion are inserted (arrangement defect portion), and the first straight pipe portion is included in the arrangement defect portion. And there is no through hole through which the second straight pipe portion passes. A support member for restricting the movement of the heat transfer tubes in the out-of-plane direction is provided in at least a part of the space surrounded by the bent portions of the plurality of heat transfer tubes existing around the arrangement defect portion.
As a result, when the heat transfer tube shakes in the out-of-plane direction, the bent portion of the heat transfer tube around the arrangement defect portion contacts the support member, and further displacement is prevented. Moreover, also about the bending part of another heat exchanger tube, the movement to the out-of-plane direction is controlled as a result of preventing the displacement of the bent part of the heat exchanger tube around an arrangement | sequence defect part. Therefore, the vibration in the bent part of the heat transfer tube group can be suppressed, and the earthquake resistance of the steam generator can be improved.
In addition, since the arrangement defect portion forms a gap corresponding to at least one heat transfer tube, the support member provided in the arrangement defect portion can have a sufficient thickness or diameter. For this reason, sufficient rigidity can be provided to the support member.
Further, when the above configuration is applied by additional work for an existing steam generator, it is sufficient to eliminate the at least one row of heat transfer tubes from the regular arrangement of a plurality of heat transfer tubes and provide a defective arrangement. The above configuration can be easily introduced to existing designs without significant changes. However, when the support member is configured using an existing heat transfer tube, the heat transfer tube may be modified into a support member without removing the heat transfer tube disposed at a position corresponding to the arrangement defect portion.

The support member may be rigidly supported with respect to the body portion in which the heat transfer tube is stored. For example, the support member may be directly supported by the trunk without using a later-described anti-vibration member.
In this case, a U-bend portion formed by the support member is eliminated by removing a portion having a low rigidity (for example, the anti-vibration member or the joint between the anti-vibration member and the holding member) from the load transmission path between the support member and the trunk portion. You can enjoy the excellent improvement effect of seismic performance.
On the other hand, if a low-rigidity portion (for example, the anti-vibration member or the joint between the anti-vibration member and the holding member) is included between the support member and the body, the rigidity of the support member itself is reduced. Even if it is improved, there is a possibility that the low rigidity portion may be damaged in the process of transmitting the load received by the support member from the heat transfer tube to the trunk.

(2) In some embodiments, in the configuration of (1) above,
The support member includes at least one partition plate fixed to the tube support plate and provided along the in-plane direction between the plurality of bent portions.
According to the configuration of (2) above, the support member includes at least one partition plate provided along the in-plane direction. Thereby, when the heat transfer tube shakes in the out-of-plane direction, the bent portion abuts on the partition plate and its movement is restricted. At this time, since the partition plate comes into contact with a large number of heat transfer tubes, it is possible to suppress shaking in a large part of the bent portion assembly with a small number of installations. Moreover, since a some bending part is divided | segmented in an out-of-plane direction by a partition plate, the moving mass of the heat exchanger tube which the one partition plate should support can be made small.
Furthermore, since the support member is fixed to the tube support plate, the support member can be supported rigidly with respect to the trunk portion. Therefore, when the support member receives the load of the bent portion due to the shaking of the heat transfer tube, the low rigidity portion may be damaged in the process of transmitting the load received by the support member from the heat transfer tube to the trunk portion. Can be prevented.

(3) In some embodiments, in the configuration of (2) above,
A holding member provided along the outer shape of a hemispherical U-bend portion formed above the tube support plate by the bent portions of the plurality of heat transfer tubes;
A plurality of anti-vibration members provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction and extending inward in the radial direction of the hemispherical shape of the U-bend portion from the holding member; Further comprising
The partition plate is sandwiched from both sides by the plurality of anti-vibration members.
In the configuration of (3), a plurality of anti-vibration members provided between the bent portions adjacent in the out-of-plane direction and extending inward in the radial direction of the hemispherical shape of the U bend portion are provided. Yes. By this anti-vibration member, fluid-excited vibration of the bent portion can be mainly suppressed. The fluid excitation vibration is vibration of a bent portion generated by a fluid flowing around the heat transfer tube (for example, secondary cooling water such as steam) or a fluid flowing in the heat transfer tube during operation of the steam generator. . Moreover, since the partition plate is pinched | interposed from the both sides by the some bracing member, the load from the bending part of a some heat exchanger tube can be received by a partition plate via a bracing member.

(4) In some embodiments, in the configuration of (3) above,
The partition plate has an arc-shaped edge along the outer shape of the U-bend portion,
The edge is fixed to the holding member.
According to the configuration of (4) above, the edge of the partition plate is fixed by the holding member, and the base side of the partition plate is fixed by the tube support plate, so the partition plate is fixed at two spaced locations. The partition plate can be more firmly fixed.

(5) In some embodiments, in the above configuration (3) or (4),
An annular support portion supported on the inner wall of the steam generator and surrounding the U-bend portion;
An edge of the partition plate is loosely fitted in a recess provided in the annular support portion.
According to the configuration of (5) above, since the edge of the partition plate is loosely fitted in the recess of the annular support portion supported by the inner wall of the steam generator (for example, the inner wall of the trunk portion), when the heat transfer tube shakes The load can be transmitted to the inner wall side of the steam generator through the partition plate and the annular support portion, and the load support capability of the bent portion caused by the shaking of the heat transfer tube can be improved. Moreover, since the partition part is loosely fitted with respect to the annular support part, the thermal stress resulting from the thermal expansion difference between the inner wall or the annular support part and the support member can be released.

(6) In some embodiments, in the above configurations (2) to (5),
The partition plate is provided with at least one opening.
According to the above (6), since the fluid (for example, secondary cooling water such as steam) flows along the out-of-plane direction through the opening of the partition plate, the partition plate impedes the heat flow in the U-bend portion. This can be suppressed.

(7) In one embodiment, in the configuration of (6) above,
The opening has an orifice portion having a minimum opening diameter.
According to the configuration of (7) above, when the partition plate is about to be displaced in the out-of-plane direction, the partition plate is displaced by the resistance force of the fluid (for example, secondary cooling water such as steam) passing through the orifice portion of the opening. Can be suppressed.

(8) In some embodiments, in any one of the above configurations (2) to (7),
The at least one partition plate includes a plurality of partition plates provided along the in-plane direction so as to be aligned in the out-of-plane direction.
According to the configuration of (8) above, the assembly of the plurality of bent portions (U bend portion) is divided into three or more in the out-of-plane direction by the plurality of partition plates. The moving mass can be further reduced.

(9) In some embodiments, in any one of the above configurations (1) to (8),
The support member includes at least one curved support bar provided along the in-plane direction and having higher rigidity than the bent portion.
According to the configuration of (9) above, when the heat transfer tube sways in the out-of-plane direction, the bent portion comes into contact with the curved support rod having higher rigidity than the bent portion and its movement is restricted. Further, since the curved support rod has a relatively small projected area with respect to the plane including the bent portion, the influence of the curved support rod on the heat flow along the out-of-plane direction can be reduced. Further, in the above configuration, since the number of heat transfer tubes excluded from the regular arrangement in order to form the arrangement defect portion can be reduced, a decrease in heat transfer efficiency due to the arrangement defect portion can be suppressed.

(10) In one embodiment, in the configuration of (9) above,
The curved support rod has the same diameter as the heat transfer tube and is solid.
According to the configuration of (10) above, the same support structure as that of the heat transfer tube can be used when supporting the curved support rod. For example, when the heat transfer tube is supported by a tube support plate configured to penetrate the heat transfer tube, the curved support bar can be supported by penetrating the tube support plate in the same manner as the heat transfer tube.

(11) In another embodiment, in the configuration of (9) above,
Further comprising at least one high-rigidity heat transfer tube having a tube thickness or a tube diameter larger than that of the heat transfer tube,
The curved support rod is a bent portion of the high-rigidity heat transfer tube.
According to the configuration of (11) above, the load of the bent portion caused by the shaking of the heat transfer tube can be supported by the high-rigidity heat transfer tube, and a fluid (for example, primary cooling water) flows through the high-rigidity heat transfer tube. As a result, a decrease in heat transfer efficiency due to the arrangement defect portion can be further suppressed.

(12) In some embodiments, in any one of the above configurations (9) to (11),
The plurality of curved support bars are connected to each other.
According to the configuration of (12) above, since the plurality of curved support bars are connected to each other, the rigidity of the curved support bars can be increased. That is, it is possible to improve the load supporting ability of the bent portion due to the shaking of the heat transfer tube.

(13) In some embodiments, in any one of the above configurations (9), (11), or (12),
The bent portions of the plurality of heat transfer tubes form a hemispherical U-bend portion above the tube support plate;
A plurality of bracing members provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction and extending along the radial direction of the hemispherical shape of the U-bend portion;
The curved support rod is
A hollow curved pipe provided in a plane parallel to the plane;
At least in a reinforcing region of the hollow curved tube portion that intersects the anti-vibration member when viewed from the out-of-plane direction, a filling member provided inside the hollow curved tube portion;
including.

In the configuration of (13), the anti-vibration member is provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction for the purpose of suppressing the fluid excitation vibration in the bent portion. When such a configuration is provided, when vibration (for example, an earthquake or the like) occurs in the U bend portion, the load caused by the heat transfer tube swaying in the out-of-plane direction is caused in the out-of-plane direction via the anti-vibration member. It is transmitted between the bent portions of adjacent heat transfer tubes. When only a hollow heat transfer tube is arranged in a region intersecting with the anti-rest member, there is a possibility that the heat transfer tube may be crushed by a load transmitted through the anti-rest member and the vibration of the entire U-bend portion cannot be suppressed. is there.
Therefore, in the configuration of (13), a curved support rod having higher rigidity than the bent portion is provided as a support member, and the curved support rod is provided in a plane parallel to a plane including the bent portion. And a filling member provided inside the hollow curved tube portion in the reinforcing region intersecting with the anti-vibration member. That is, in the reinforcing region of the hollow curved tube portion that intersects with the bracing member, since the filling member is packed inside the hollow curved tube portion, the rigidity becomes higher than that of the hollow heat transfer tube. Since the load resulting from the out-of-plane vibration of the heat transfer tube mainly acts on the reinforcing region of the hollow curved tube portion having high rigidity, the load can be received without collapsing the hollow curved tube portion. Therefore, the earthquake resistance of the U bend portion can be improved.
Moreover, you may use a heat exchanger tube as a hollow curved tube part. That is, a filling member may be provided inside the heat transfer tube to form a support member (curved support rod). Thereby, the earthquake-proof construction for implement | achieving the structure of said (13) with respect to the existing steam generator can be performed easily.

(14) In one embodiment, in the configuration of (13) above,
A plurality of the curved support rods and a plurality of the bracing members are alternately arranged in the out-of-plane direction,
A load transmission path that penetrates the U-bend portion in the out-of-plane direction by the reinforcing region of the hollow curved tube portions arranged in the out-of-plane direction, the filling member in the reinforcing region, and the anti-vibration member. Is formed.
According to the configuration of (14) above, the load transmission path is formed by the reinforcing region of the hollow curved tube portion, the filling member in the reinforcing region, and the anti-vibration member. On the path, the rigidity in the load transmission direction can be increased. Therefore, the earthquake resistance of the U bend portion can be effectively improved.

(15) In one embodiment, in the configuration of (14) above,
An annular support portion supported on the inner wall of the steam generator and surrounding the U-bend portion;
At both ends of the load transmission path, the curved support rod or the anti-vibration member is loosely fitted in a recess provided in the annular support portion.
According to the configuration of (15) above, since the curved support rod or the anti-vibration member is loosely fitted in the concave portion of the annular support portion supported by the inner wall of the steam generator, the annular support portion and the curved support rod Alternatively, the load from the load transmission path can be received by the inner wall while releasing the stress caused by the difference in thermal expansion with the vibration-preventing member.

(16) In some embodiments, in the above configurations (13) to (15),
The filling member includes a plurality of sections provided in a cross-section along the tube length direction of the hollow curved tube portion, including the reinforcing region of the hollow curved tube portion and a pair of anti-vibration members located on both sides of the reinforcing region. Composed of sections.
According to the configuration of (16), since the filling member is formed by the divided structure composed of a plurality of sections, each section of the filling member and the hollow curved tube portion are arranged on the load transmission path along the out-of-plane direction. It is possible to prevent a gap from being formed between the inner wall surface and the inner wall surface. As a result, the hollow curved tube portion can be prevented from being crushed, and the vibration of the entire U bend portion can be effectively suppressed.

(17) In some embodiments, in the above configurations (13) to (16),
The curved support rod is formed by installing the filling member inside some of the heat transfer tubes.
According to the configuration of (17) above, it is possible to easily perform the earthquake resistant construction for realizing the configurations of (13) to (16) with respect to the existing steam generator.

(18) In some embodiments, in any one of the configurations (1) to (17),
The support member includes at least one horizontal support bar that extends in the horizontal direction along the out-of-plane direction or the in-plane direction and is supported at both ends by the inner wall of the steam generator.
According to the configuration of (18), when the heat transfer tube sways in the out-of-plane direction, the bent portion abuts on the horizontal support rod and its movement is restricted. Further, since the horizontal support bar has a relatively small projected area in the in-plane direction, the influence of the horizontal support bar on the heat flow along the out-of-plane direction can be reduced.

(19) In one embodiment, in the configuration of (18) above,
An annular support portion that is supported on the inner wall of the steam generator and surrounds a hemispherical U-bend portion formed above the tube support plate by the bent portions of the plurality of heat transfer tubes;
The both ends of the at least one horizontal support rod are supported by the annular support portion.
According to the configuration of (19) above, both ends of the horizontal support rod are supported by the annular support portion that is rigidly supported by the inner wall of the steam generator (for example, the inner wall of the trunk portion). It is possible to improve the load supporting ability of the bent portion resulting from the above.

(20) A nuclear power plant according to at least one embodiment of the present invention,
A reactor vessel configured to heat the primary coolant;
A steam turbine configured to be driven by the steam of the secondary coolant;
The steam generator according to any one of (1) to (19), configured to generate the steam of the secondary coolant by heat exchange with the primary coolant;
It is characterized by providing.

  According to the configuration of (20) above, for the reasons described above, it is possible to suppress the vibration at the bent portion of the heat transfer tube and to improve the seismic performance of the steam generator, thereby providing a highly reliable nuclear power plant. it can.

(21) The seismic reinforcement method for a steam generator according to at least one embodiment of the present invention includes:
A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bent portion located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes, and a tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted. A method for seismic reinforcement of a steam generator for generating steam by heat exchange with the fluid flowing in the heat transfer pipe,
An installation step of installing in the steam generator a support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction perpendicular to the plane including the bent portion;
In the steam generator, the plurality of bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and the plurality of bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion of the plurality of heat transfer tubes pass are arranged according to a regular arrangement in a top view of the tube support plate,
In the installation step, the support member is installed in place of the heat transfer tube in at least one row along the in-plane direction or the out-of-plane direction in the regular array.

According to the above method (21), when the heat transfer tube sways in the out-of-plane direction, the bent portion abuts on the support member and further displacement is prevented, so that the displacement of the bent portion is kept small. be able to. Therefore, the vibration in the bent part of the heat transfer tube can be suppressed, and the earthquake resistance of the steam generator can be improved.
In addition, in at least one row along the in-plane direction or the out-of-plane direction among the regular arrangement of the plurality of heat transfer tubes, the support members are installed instead of the heat transfer tubes. Seismic construction can be easily performed according to the method of 21).

(22) In some embodiments, in the method of (21) above,
In the installation step, at least one curved support bar provided along the in-plane direction and having higher rigidity than the bent portion is installed as the support member.
According to the above method (22), when the heat transfer tube sways in the out-of-plane direction, the bent portion comes into contact with the curved support rod having higher rigidity than the bent portion, and its movement is restricted. , Can suppress the swing of the bent portion. Moreover, since the curved support rod has a relatively small projected area in the in-plane direction, the influence of the curved support rod on the heat flow along the out-of-plane direction can be reduced.

(23) In one embodiment, in the method of (22) above,
In the installation step, the curved support rod is formed by providing a filling member inside a heat transfer tube to be reinforced which is a part of the plurality of heat transfer tubes.
According to the above method (23), since it is not necessary to remove a part of the heat transfer tube when installing the support member on the existing steam generator, the existing steam generator is easily seismic-proofed. be able to.

(24) In one embodiment, in the method of (23) above,
The bent portions of the plurality of heat transfer tubes form a hemispherical U-bend portion above the tube support plate;
The steam generator is provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction and extends along the hemispherical radial direction of the U bend portion; and Further comprising
In the installation step,
The filling member is provided inside the reinforcement target heat transfer tube in a reinforcement region of the reinforcement target heat transfer tube intersecting with the anti-vibration member when viewed from the out-of-plane direction.
According to the above method (24), in the reinforcement region of the reinforcement target heat transfer tube intersecting with the bracing member, since the filling member is packed inside the reinforcement target heat transfer tube, the rigidity is higher than that of the hollow heat transfer tube. Get higher. Since the load caused by the vibration component in the out-of-plane direction mainly acts on the reinforced region of the heat transfer tube with high rigidity, the load to be reinforced can be received without being crushed. Therefore, the earthquake resistance of the U bend portion can be improved.

(25) In one embodiment, in the method of (24) above,
A plurality of the curved support rods and a plurality of the bracing members are alternately arranged in the out-of-plane direction;
In the installation step, the U-bend portion is penetrated in the out-of-plane direction by the reinforcement region of the heat transfer tubes to be reinforced arranged in the out-of-plane direction, the filling member in the reinforcement region, and the anti-vibration member. A load transmission path is formed.
According to the method of (25) above, since the load transmission path is formed by the reinforcement region of the heat transfer tube to be reinforced, the filling member in the reinforcement region, and the anti-vibration member, the U-bend portion in the out-of-plane direction The rigidity of can be increased. Therefore, the earthquake resistance of the U bend portion can be effectively improved.

  According to at least one embodiment of the present invention, when a vibration in the out-of-plane direction of the heat transfer tube occurs due to an earthquake or the like, the bent portion of the heat transfer tube contacts the support member, and further displacement is prevented. The bending portion can be kept small. Therefore, the vibration in the bent part of the heat transfer tube can be suppressed, and the earthquake resistance of the steam generator can be improved.

It is sectional drawing of the steam generator which concerns on one Embodiment. It is a perspective view of the U bend part provided with the fluid excitation vibration suppression structure which concerns on one Embodiment. It is a perspective view which shows the modification of the U bend part provided with the fluid excitation vibration suppression structure which concerns on one Embodiment. It is the figure which expanded a part of U bend part shown in FIG. It is a top view of the pipe support plate concerning one embodiment. It is sectional drawing (AA cross section) which shows the U bend part provided with the earthquake-resistant structure which concerns on one Embodiment. It is a top view of the pipe support plate concerning the modification of one embodiment. It is sectional drawing (BB cross section) which shows the U bend part provided with the earthquake proof structure which concerns on the modification of one Embodiment. It is a figure which shows an example of the support structure of the partition plate by a bracing member. It is a figure which shows an example of the support structure of the partition plate by a 2nd holding member (bridge). It is a figure which shows an example of the support structure of the partition plate by a ring support part. It is a fragmentary sectional view showing an example of 1 composition of a partition plate. It is a fragmentary sectional view which shows the other structural example of a partition plate. It is a top view of the pipe support plate concerning other embodiments. It is sectional drawing (CC cross section) which shows the U bend part provided with the earthquake proof structure which concerns on other embodiment. It is a top view of the pipe support plate concerning other embodiments. It is sectional drawing (DD cross section) which shows the U bend part provided with the earthquake proof structure which concerns on other embodiment. It is a partial side view which shows the example of 1 structure of a curved support bar. It is a partial side view which shows the other structural example of a curved support bar. It is sectional drawing which shows the U bend part provided with the earthquake proof structure which concerns on the modification of other embodiment. It is sectional drawing (EE cross section) of the U-bend part shown to FIG. 15A. It is a figure for demonstrating the earthquake-proof reinforcement method of the steam generator which concerns on one Embodiment. It is sectional drawing which shows the structural example of a filling member. It is FF sectional drawing of FIG. 17A. It is a side view which shows the structural example of a wire edge part. It is a side view which shows the other structural example of a filling member. It is a side view which shows the other structural example of a filling member.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Absent.
In this embodiment, after first explaining the whole structure of a steam generator, the earthquake-resistant structure of a steam generator is demonstrated.

FIG. 1 is a schematic configuration diagram of a steam generator 1 according to an embodiment.
In some embodiments, the steam generator 1 includes a plurality of heat transfer tubes 3 disposed inside the trunk portion 2, and a tube support plate 7 through which the plurality of heat transfer tubes 3 are inserted. The steam is generated by heat exchange with the fluid flowing in the plurality of heat transfer tubes 3.
The plurality of heat transfer tubes 3 include a first straight pipe portion 4 located on the fluid inlet side, a second straight pipe portion 5 located on the fluid outlet side, the first straight pipe portion 4 and the second straight pipe, respectively. And a bent portion 6 located between the portions 5.
A plurality of through holes 71 (see FIGS. 5A, 6A, 11A, and 12A) through which the first straight pipe portion 4 and the second straight pipe portion 5 are inserted are formed in the pipe support plate 7.

  In FIG. 1, the steam generator 1 used for the nuclear power plant provided with the pressurized water reactor (PWR: Pressurized Water Reactor) is illustrated as one Embodiment. A pressurized water reactor uses light water (primary coolant) as a reactor coolant and neutron moderator, and a steam generator as high-temperature high-pressure water that does not boil the primary coolant (primary coolant) over the entire core Send to 1. In the steam generator 1, the heat of the high-temperature and high-pressure primary cooling water is transmitted to the secondary coolant (secondary cooling water), and the secondary cooling water is used as steam. This steam is sent to a steam turbine to drive the steam turbine. The output shaft of the steam turbine is connected to the input shaft of the generator, and the generator is driven by the steam turbine to generate power.

Here, the specific structural example of the steam generator 1 shown in FIG. 1 is demonstrated.
The body portion 2 of the steam generator 1 has a hollow cylindrical shape that extends in the vertical direction and is hermetically sealed, and the lower half portion has a smaller diameter than the upper half portion. In the body portion 2, a water chamber 8 is disposed on the lower end side, and a steam discharge port 15 is disposed on the upper end side.
A cylindrical tube group outer cylinder (inner wall) 9 is provided from the lower half portion of the trunk portion 2 to the upper half portion, and is arranged with a predetermined distance from the inner wall surface of the trunk portion 2. The lower end portion of the tube group outer tube 9 extends to a tube plate 10 disposed below in the lower half of the body portion 2. A plurality of heat transfer tubes 3 are arranged in the tube group outer tube 9. That is, the tube group outer tube 9 and the plurality of heat transfer tubes 3 are stored in the body portion 2 provided on the outer peripheral side of the tube group outer tube 9.

As described above, each heat transfer tube 3 includes the first straight pipe portion 4 located on the inlet 8c (entry chamber 8b) side, the second straight pipe portion 5 located on the outlet 8e (exit chamber 8d) side, and the first And a bent portion 6 located between the straight pipe portion 4 and the second straight pipe portion 5. In the illustrated example, the first straight pipe portion 4 and the second straight pipe portion 5 extend in the vertical direction, and one end of the bent portion 6 is connected to the upper end of the first straight pipe portion 4 so that the second straight pipe portion 4 is connected. The other end of the bent portion 6 is connected to the upper end of the tube portion 5. That is, the bent portion 6 is located above the first straight pipe portion 4 and the second straight pipe portion 5. Moreover, each lower end part of the 1st straight pipe part 4 and the 2nd straight pipe part 5 is supported by the tube sheet 10, and each intermediate part of the 1st straight pipe part 4 and the 2nd straight pipe part 5 is plural. The tube support plate 7 is supported. A plurality of through holes 71 (see FIGS. 5A, 6A, 11A, and 12A) are formed in the tube support plate 7 as described above, and the first straight pipe portion 4 and The second straight pipe portion 5 penetrates mainly in a non-contact state.
A portion where the bent portions 6 of the plurality of heat transfer tubes 3 are gathered is referred to as a U-bend portion 20. The U-bend portion 20 has a hemispherical shape and is formed above the tube support plate 7.
The specific configuration of the U bend unit 20 will be described later.

  The water chamber 8 provided at the lower end of the body portion 2 is partitioned into an entrance chamber 8b and an exit chamber 8d by a partition wall 8a. In the entrance chamber 8b, an inlet (inlet nozzle) 8c communicating with the outside of the body portion 2 is formed, and one end portion of each heat transfer tube 3 communicates with the entrance chamber 8b. The exit chamber 8d is formed with an outlet (exit nozzle) 8e communicating with the outside of the body portion, and the other end portion of each heat transfer tube 3 communicates with the exit chamber 8d. A cooling water pipe through which primary cooling water is sent from the pressurized water reactor is connected to the inlet 8c. The outlet 8e is connected to a cooling water pipe for sending the primary cooling water after heat exchange to the pressurized water reactor.

In the upper half of the body portion 2, a steam / water separator 11 that separates the feed water W into steam S and hot water, and moisture that removes the moisture of the separated steam S to make it close to dry steam. A separator 12 is provided. Between the steam / water separator 11 and the plurality of heat transfer tubes 3, a water supply tube 13 for supplying secondary cooling water into the body 2 from the outside is inserted.
A steam discharge port 15 is formed at the upper end of the body 2. Further, in the lower half of the body part 2, the secondary cooling water supplied from the water supply pipe 13 into the body part 2 is caused to flow down between the body part 2 and the tube group outer tube 9 by the tube plate 10. A water supply path 14 that is folded back and raised along the heat transfer tube 3 is provided. The steam outlet 15 is connected to a cooling water pipe for sending steam to the turbine, and the water supply pipe 13 is connected to a cooling water pipe for supplying secondary cooling water. The secondary cooling water is obtained by cooling the steam used in the turbine with a condenser and condensing it.

  Regarding the operation of the steam generator 1 having the above-described configuration, the primary cooling water heated in the pressurized water reactor is introduced from the inlet 8c of the steam generator 1 into the entrance chamber 8b and then from the entrance chamber 8b to the plurality of heat transfer tubes 3. It is introduced into the interior, circulates through the heat transfer tubes 3, reaches the exit chamber 8d, and is discharged from the exit chamber 8d to the outside of the steam generator 1 through the outlet 8e. On the other hand, the secondary cooling water cooled by the condenser is sent to the water supply pipe 13 and rises along the plurality of heat transfer pipes 3 through the water supply path 14 in the trunk portion 2. At this time, heat exchange is performed between the high-pressure and high-temperature primary cooling water and the secondary cooling water in the body portion 2. Then, the cooled primary cooling water is returned to the pressurized water reactor from the exit chamber 8d. On the other hand, the secondary cooling water heat-exchanged with the high-pressure and high-temperature primary cooling water rises in the body portion 2 and is separated into steam and hot water by the steam separator 11. The separated steam is sent to the turbine after moisture is removed by the moisture separator 12.

In one embodiment, the steam generator 1 may further include a fluid excitation vibration suppressing structure for improving resistance to fluid excitation vibration as illustrated in FIGS. 2 to 4. FIG. 2 is a perspective view of the U-bend portion 20 including the fluid excitation vibration suppressing structure according to the embodiment. FIG. 3 is a perspective view showing a modified example of the U-bend portion 20 including the fluid excitation vibration suppressing structure according to the embodiment. FIG. 4 is an enlarged view of a part of the U-bend portion 20 shown in FIG.
The fluid excitation vibration is generated by secondary cooling water flowing around the heat transfer tube 3 (bending portion 6) of the U bend portion 20 or primary cooling water flowing inside the heat transfer tube 3 (bending portion 6) of the U bend portion 20. Vibration. When the vibration of the heat transfer tube 3 due to the fluid excitation vibration becomes large, the heat transfer tubes 3 may come into contact with each other and the heat transfer tube 3 may be worn. The following fluid excitation vibration suppression structure is used for the purpose of suppressing fluid excitation vibration.

With reference to FIG.2 and FIG.3, the specific structural example of the U-bend part 20 is demonstrated first.
In the U-bend portion 20, the bent portions 6 of the heat transfer tubes 3 are arranged in order of increasing curvature radius of the bent portions 6 toward the outside (upper side), and the bent portions 6 are arranged in this manner. The upper ends of the plurality of heat transfer tubes 3 are formed in a hemispherical shape by changing the radius of curvature of the bent portion 6 while overlapping in a direction (out-of-plane direction) orthogonal to a plane including As a result, a U-bend portion 20 having a hemispherical shape as a whole is formed by arranging the bent portions 6 in a collective arrangement. The portion closest to the steam outlet 15 shown in FIG. 1 is the top of the U bend portion 20.

  In one embodiment, the steam generator 1 includes the first holding member 21 and the anti-vibration member 22 as the fluid excitation vibration suppressing structure described above.

The first holding member 21 is provided along the outer shape of the U-bend portion 20.
The anti-vibration member 22 is provided between the bent portions 6 of the adjacent heat transfer tubes 3 in the out-of-plane direction orthogonal to the plane including the bent portion 6. The anti-vibration member 22 extends from the first holding member 21 toward the inner side in the radial direction of the hemispherical shape of the U bend portion 20. That is, the brace is provided between the heat transfer tubes 3 arranged corresponding to a regular array 70 (see FIGS. 5A, 6A, 11A, and 12A) described later.

  Specifically, the anti-vibration member 22 is inserted between the rows of the bent portions 6 stacked in the out-of-plane direction, thereby connecting the adjacent bent portions 6 in the out-of-plane direction. For example, the anti-vibration member 22 is a member in which a bar-shaped member having a rectangular cross section is formed in a V shape. The bent member 22 has a bent portion arranged at the same diameter portion in the row of the bent portions 6 that are stacked, and an end portion outside the arc portion of the bent portion 6 having the largest radius of curvature. It is protruding. That is, as shown in FIG. 2, the end portion 22 a of the anti-vibration member 22 protrudes from the hemispherical surface 20 a of the U-bend portion 20 constituted by the bent portion 6 of the outermost heat transfer tube 3. As a result, the end 22a of the anti-vibration member 22 is arranged in a line in the horizontal direction (in-plane direction) along the plane including the bent portion 6 along the arc forming the outer diameter of the U-bend portion 20. Yes. In addition, a plurality of end portions 22a arranged in a line in this way are arranged in the out-of-plane direction with a gap corresponding to the heat transfer tube 3.

  Further, the anti-vibration members 22 may be paired with a small V-shaped member disposed inside a large V-shaped member. In the example shown in FIG. 2, three pairs of the anti-vibration members 22 are arranged on the bent portion 6 of the heat transfer tube 3. Furthermore, the part inserted between the row | line | columns of the piled heat exchanger tube 3 may be formed with the material (for example, SUS405) preferable for suppressing the vibration.

As shown in FIGS. 2 and 4, the first holding member 21 is welded to the end portion 22 a of the anti-vibration member 22 to connect the end portions 22 a of the plural anti-vibration members 22. The first holding member 21 is an arc-shaped rod-like member attached along the outer periphery of the U bend portion 20, that is, the hemispherical outer periphery (hemispheric surface 20 a) of the U bend portion 20. The first holding member 21 extends in a direction orthogonal to the direction in which the plurality of heat transfer tubes 3 are stacked.
The plurality of first holding members 21 may be connected by a second holding member (bridge) 24.
The second holding member 24 is an arc-shaped and plate-shaped member disposed along the outer periphery of the U bend portion 20, that is, the hemispherical outer periphery (hemispheric surface 20 a) of the U bend portion 20. The second holding member 24 extends along the direction in which the bent portion 6 of the heat transfer tube 3 extends in the U bend portion 20. Although one second holding member 24 is shown in FIG. 4, a plurality of second holding members 24 are arranged in a direction parallel to the direction in which the plurality of bent portions 6 are overlapped.
The vibrations of the plurality of anti-vibration members 22 connected by the first holding member 21 and the second holding member 24 are restricted by a vibration restricting structure described later.

In a modification of the embodiment, as shown in FIGS. 3 and 4, the steam generator 1 further includes an earthquake resistant structure for suppressing the vibration of the fluid excitation vibration suppressing structure when vibration such as an earthquake occurs. May be.
As shown in FIGS. 3 and 4, the steam generator 1 has an annular support portion 31 (31 </ b> A, 31 </ b> B), an arm-shaped support portion 32 (32 </ b> A, 32 </ b> B), and an outer cylinder support portion 33 ( 33A, 33B).

The annular support portion 31 is formed in an annular shape, and is provided above the bent portion 6 so as to surround the U bend portion 20. The annular support portion 31 may be arranged so as to be concentric with the U bend portion 20 in plan view (top view). Further, the annular support portion 31 is supported by the tube group outer cylinder (inner wall) 9 surrounding the outer periphery of the U-bend portion 20 by the arm-shaped support portion 32. The annular support portion 31 has a predetermined distance from the U bend portion 20 and the tube group outer tube 9.
The arm-shaped support portion 32 is attached between the tube group outer cylinder 9 and the ring support portion 31 so that the tube group outer tube 9 supports the ring support portion 31. For example, a plurality of arm-shaped support portions 32 formed in a rod shape are provided on the outer side in the radial direction of the annular support portion 31. The plurality of arm-shaped support portions 32 extend radially from the annular support portion 31 toward the tube group outer tube 9.
As a specific configuration example, the annular support portion 31 includes a lower annular support portion 31 </ b> A on the tube support plate 7 side and an upper annular support portion 31 </ b> B on the top side of the U bend portion 20. The lower annular support portion 31A has a larger diameter than the upper annular support portion 31B. The arm-shaped support part 32 connects a plurality of lower arm-shaped support parts 32A for connecting the lower ring support part 31A and the tube group outer cylinder 9, and the upper ring support part 31B and the tube group outer cylinder 9 to each other. A plurality of upper arm-shaped support portions 32B. In addition, the number of installation of the annular support part 31 is not limited to this.

  The outer cylinder support part 33 is provided between the trunk | drum 2 and the pipe group outer cylinder 9, and makes the trunk | drum 2 support the pipe group outer cylinder 9. As shown in FIG. A plurality of outer tube support portions 33 may be provided in the circumferential direction between the body portion 2 and the tube group outer tube 9. With the above configuration, the annular support portion 31 is supported by the trunk portion 2 via the arm-shaped support portion 32 and the tube group outer tube 9.

  In one embodiment, the connecting portion between the annular support portion 31 and the arm-shaped support portion 32, the connecting portion between the arm-shaped support portion 32 and the tube group outer tube 9, and the tube group outer tube 9 and the body portion 2 and the outer portion. The connecting portion with the tube support portion 33 is rigidly connected by joining means such as welding or bolts. Therefore, the annular support portion 31 is supported rigidly with respect to the trunk portion 2.

  According to the above configuration, when the U-bend portion 20 vibrates in a direction (horizontal direction) parallel to the radial direction of the body portion 2 having a circular cross section due to an earthquake or the like, the annular support portion 31 and the arm-shaped support portion 32 are provided. Since the vibration of the U-bend portion 20 can be received by the body portion 2 through the outer cylinder support portion 33, the earthquake resistance of the U-bend portion 20 is ensured. In addition, since the annular support part 31 does not restrain the heat transfer tube 3 of the U bend part 20, when the steam generator 1 is operated, the secondary that passes between the annular support part 31 and the U bend part 20. Vibration wear and the like of the bent portion 6 due to cooling water can be suppressed. Therefore, according to the said earthquake-resistant structure which has the annular support part 31, the influence which it has on the tolerance with respect to the fluid excitation vibration of the heat exchanger tube 3 can be reduced, and the fluid excitation vibration of the heat exchanger tube 3 can be suppressed.

Here, a vibration restricting structure for restricting vibrations of the plurality of anti-vibration members 22 will be described.
As described above, the plurality of bracing members 22 are disposed between the plurality of bent portions 6, and the end portions 22 a of the plurality of bracing members 22 are connected by the first holding member 21. Further, the plurality of first holding members 21 are connected by the second holding member 24.
In one embodiment, the steam generator 1 further includes a restricting member 25 for restricting vibration of the anti-vibration member 22. The restricting member 25 is attached to the annular support portion 31, and is configured to sandwich the second holding member 24 with a predetermined gap and restrict the movement of the second holding member 24 in the out-of-plane direction. Has been. More specifically, the regulating member 25 of the annular support portion 31 has a recess 25a, and the second holding member 24 is sandwiched between the recess 25a with a predetermined gap. For example, the regulating member 25 is rigidly joined to the annular support portion 31 by joining means such as welding. The interval between the restriction member 25 and the second holding member 24 may be smaller than the interval between the annular support portion 31 and the plurality of heat transfer tubes 3 of the U bend portion 20.

  The steam generator 1 which concerns on this embodiment is further provided with the following structures as an earthquake-resistant structure which can improve the earthquake resistance in the bending part 6 of the heat exchanger tube 3. FIG.

  As shown in FIGS. 5A and 5B, FIGS. 6A and 6B, FIGS. 10A and 10B, and FIGS. 11A to 11C, the steam generator 1 includes a plurality of heat transfer tubes in the out-of-plane direction at the U-bend portion 20. 3 (bending portion 6) is further provided with support members 40 (40A, 40B), 50, 60 for restricting movement. 5A is a plan view of the tube support plate 7 according to the embodiment, and FIG. 5B is a cross-sectional view (A-A cross section) showing the U-bend portion 20 including the earthquake-resistant structure according to the embodiment. is there. FIG. 6A is a plan view of a tube support plate 7 according to a modification of the embodiment, and FIG. 6B is a cross-sectional view (B--) showing the U-bend portion 20 including the earthquake-resistant structure according to the modification of the embodiment. B cross section). FIG. 10A is a plan view of a tube support plate 7 according to another embodiment, and FIG. 10B is a cross-sectional view (CC cross-section) showing a U-bend portion 20 provided with an earthquake-resistant structure according to another embodiment. is there. FIG. 11A is a plan view of a tube support plate 7 according to still another embodiment, and FIG. 11B is a cross-sectional view (DD cross section) showing a U-bend portion 20 provided with an earthquake-resistant structure according to still another embodiment. ).

Hereinafter, a specific configuration of the support members 40, 50, 60 will be described.
As shown in FIGS. 5A, 6A, 10A, and 11A, the tube support plate 7 has a plurality of through holes 71 through which the first straight tube portion 4 and the second straight tube portion 5 of the plurality of heat transfer tubes 3 pass. Is formed. The plurality of through-holes 71 have a tube support plate 7 such that a plurality of bent portions 6 having different curvature radii are arranged along the in-plane direction, and a plurality of bent portions 6 having the same curvature radius are arranged in the out-of-plane direction. Are arranged according to the regular arrangement 70 in a top view. That is, as shown in FIG. 1, the bent portions 6 arranged in accordance with the regular array 70 have a plurality of bent portions 6 a ₁ , 6 a ₂ , 6 a ₃ ,... Arranged in the in-plane direction, and A plurality of bent portions 6a ₁ , 6b ₁ , 6c ₁ ,... Having the same radius of curvature are arranged along the out-of-plane direction.

Returning to FIGS. 5A, 6A, 10A, and 11A, the regular array 70 includes an array defect 72 in which the heat transfer tubes 3 do not exist in at least one line along the in-plane direction or the out-of-plane direction.
And the supporting members 40, 50, 60 for restricting the movement of the plurality of heat transfer tubes 3 (bending portions 6) in the out-of-plane direction are bent portions of the plurality of heat transfer tubes 3 existing around the arrangement defect portion 72. 6 is provided in at least a part of the space surrounded by 6.

  According to the above configuration, the plurality of through holes 71 through which the first straight pipe portion 4 and the second straight pipe portion 5 pass are arranged according to the regular arrangement 70 in a top view of the pipe support plate 7, and this regular arrangement 70 is The arrangement defect part 72 in which the heat transfer tubes 3 are not present in at least one line along the in-plane direction or the out-of-plane direction is included. That is, at least one row of the regular array 70 defined by the through holes 71 through which the first straight pipe portion 4 and the second straight pipe portion 5 are inserted is missing (arrangement defect portion 72). There is no through hole 71 through which the first straight pipe portion 4 and the second straight pipe portion 5 pass. A support member 40 for restricting the movement of the heat transfer tube 3 in the out-of-plane direction is provided in at least a part of the space surrounded by the bent portions 6 of the plurality of heat transfer tubes 3 present around the arrangement defect portion 72. 50, 60 are provided.

As a result, when the heat transfer tube 3 sways in the out-of-plane direction, the bent portion 6 of the heat transfer tube 3 around the arrangement defect portion 72 abuts against the support members 40, 50, 60, and further displacement is prevented. Is done. Moreover, also about the bending part 6 of the other heat exchanger tube 3, as a result of the displacement of the bending part 6 of the heat exchanger tube 3 around the arrangement | positioning defect part 72 being blocked | prevented, the movement to an out-of-plane direction is controlled. Therefore, the vibration in the bending part 6 of the U bend part 20 can be suppressed, and the earthquake resistance of the steam generator 1 can be improved.
Further, since the arrangement defect portion 72 forms a gap corresponding to at least one heat transfer tube 3, the support members 40, 50, 60 provided in the arrangement defect portion 72 may have a sufficient thickness or diameter. it can. For this reason, sufficient rigidity can be provided to the support members 40, 50, 60.

  Furthermore, when the above configuration is applied by additional work on the existing steam generator 1, at least one row of the heat transfer tubes 3 may be excluded from the regular array 70 of the plurality of heat transfer tubes 3, and the arrangement defect portion 72 may be provided. The above configuration can be easily introduced into an existing design without significantly changing the regular rule array 70. However, when the support member 60 is configured using the existing heat transfer tube 3 as shown in FIGS. 12A and 12B, without removing the heat transfer tube 3 disposed at a position corresponding to the arrangement defect portion 72, The heat transfer tube 3 may be modified to the support member 60.

The support members 40, 50, 60 may be rigidly supported with respect to the body portion 2 in which the heat transfer tube 3 is stored. For example, the support members 40, 50, and 60 are directly supported by the body portion 2 without using the anti-vibration member 22. Here, the direct support to the body portion 2 means that the tube body is attached to the tube group outer tube 9 connected to the body portion 2 via the outer tube support portion 33 as shown in FIG. The support members 40, 50, 60 are connected via members other than the anti-vibration member 22 as in the case of being attached to the tube support plate 7 connected to the body portion 2 via the tube 9 and the outer tube support portion 33. Is rigidly connected to the body 2.
Accordingly, a portion having low rigidity from the load transmission path between the support members 40, 50, 60 and the trunk portion 2 (for example, the anti-vibration member 22 or the joint portion between the anti-vibration member 22 and the first holding member 21). Thus, the excellent improvement effect of the seismic performance of the U-bend portion 20 by the support members 40, 50, 60 can be enjoyed.

  Next, each embodiment of the steam generator 1 provided with the earthquake-resistant structure mentioned above is described in detail.

  As shown in FIG. 5A, FIG. 5B and FIG. 6A, FIG. 6B, in one embodiment, the support member 40 is fixed to the tube support plate 7 and is provided between the plurality of bent portions 6 along the in-plane direction. And at least one partition plate. In this case, as shown in FIG. 5A, the alignment defect portion 72 is formed in a straight line shape in the out-of-plane direction. And the partition plate 40 is arrange | positioned so that it may occupy at least one part of the space enclosed by the bending part 6 of the some heat exchanger tube 3 which exists around the linear array defect part 72. FIG. The partition plate 40 is rigidly fixed to the tube support plate 7 by bolt fastening or welding. The partition plate 40 may be provided only above the tube support plate 7, and may extend not only above the tube support plate 7 but also below. The lower portion of the partition plate 40 is formed in a semicircular shape corresponding to the outer diameter of the hemispherical U-bend portion 20, and the lower portion of the partition plate 40 is formed by the first straight pipe portion 4 and the second straight pipe portion. It may be formed in a rectangular plate shape corresponding to the outer diameter of the aggregate of the tube portions 5. Furthermore, the edge part of the partition plate 40 may be located outside the heat transfer tube 3. However, the shape of the partition plate 40 is not limited to this, and may be another shape such as a square shape.

As shown in FIGS. 5A and 5B, in one embodiment, one alignment defect 72 is formed linearly along the out-of-plane direction so as to pass through the center of the tube support plate 7 in the in-plane direction. . Then, one partition plate 40 is provided at a position corresponding to the arrangement defect portion 72 of the tube support plate 7. That is, the partition plate 40 is erected on the tube support plate 7 along the in-plane direction in the space formed by the arrangement defect portion 72.
According to this configuration, when the heat transfer tube 3 shakes in the out-of-plane direction, the bent portion 6 abuts on the partition plate 40 and its movement is restricted. At this time, since the partition plate 40 is in contact with the bent portions 6 of the large number of heat transfer tubes 3, it is possible to suppress the shaking of the majority of the bend portions 20 with a small number of installations. Moreover, since the some bending part 6 is divided | segmented in an out-of-plane direction by the partition plate 40 (in this case, two), the moving mass of the heat exchanger tube which the one partition plate 40 should support can be made small.
Furthermore, since the partition plate 40 is fixed to the tube support plate 7, the partition plate 40 can be rigidly supported with respect to the trunk portion 2. Therefore, when the partition plate 40 receives the load of the bent portion 6 due to the shaking of the heat transfer tube 3, the low rigidity portion in the process of transmitting the load received by the partition plate 40 from the heat transfer tube 3 to the body portion 2. Can be prevented from being damaged.

As shown in FIGS. 6A and 6B, in a modification of the embodiment, at least one partition plate 40 includes a plurality of partition plates 40A provided along the in-plane direction so as to be aligned in the out-of-plane direction. 40B included. In the examples shown in these drawings, the two arrangement defect portions 72A and 72B are formed so as to pass through two different places in the out-of-plane direction, and each extend linearly along the in-plane direction. Yes. Two partition plates 40A and 40B are provided at positions corresponding to the alignment defect portions 72A and 72B of the tube support plate 7 in the space formed by the alignment defect portions 72A and 72B. That is, the two partition plates 40A and 40B are erected on the tube support plate 7 so as to be parallel to each other and along the in-plane direction.
According to this structure, since the aggregate | assembly (U bend part 20) of the some bending part 6 is divided | segmented into 3 or more in an out-of-plane direction by several partition plate 40A, 40B, one partition plate 40 (40A, 40A, 40B) can reduce the moving mass of the heat transfer tube 3.

  7 to 9 show configuration examples for supporting the edge 40a side of the partition plate 40 (40A, 40B). The edge 40a of the partition plate 40 is an edge region on the side far from the tube support plate 7 (the top side of the U-bend portion 20).

FIG. 7 is a view showing an example of a support structure of the partition plate 40 by the anti-vibration member 22.
In the example shown in FIG. 7, the partition plate 40 is sandwiched from both sides by the plurality of anti-vibration members 22. Note that the anti-vibration member 22 is the same as that shown in FIGS. 2 and 3 described above. The plurality of bent portions 6 extend along the in-plane direction, while the anti-vibration member 22 is disposed between the plurality of bent portions 6 and extends along the in-plane direction like the bent portions 6. Exist.
The partition plate 40 is provided in parallel to a plane passing through the anti-vibration member 22 or a plane passing through the bent portion 6. The edge side (radially outward side) of the partition plate 40 is supported by the pair of anti-vibration members 22 arranged on both sides in the in-plane direction of the partition plate 40. At this time, the partition plate 40 and the anti-vibration member 22 may not be fixed, or may be fixed by welding or the like.
According to this configuration, since the partition plate 40 is sandwiched from both sides by the plurality of anti-vibration members 22, the load from the bent portions 6 of the plurality of heat transfer tubes 3 is divided via the anti-vibration members 22. Can be received at.

FIG. 8 is a diagram illustrating an example of a support structure of the partition plate 40 (40A, 40B) by the holding member (second holding member 24).
In the example shown in FIG. 8, the partition plate 40 has an arcuate edge portion 40 a along the outer shape of the U-bend portion 20, and this edge portion 40 a is fixed to the second holding member (bridge) 24. The The edge 40a of the partition plate 40 and the second holding member 24 may be fixed by welding or the like. As described above, the second holding member 24 is formed along the outer shape of the hemispherical U-bend portion 20 in the out-of-plane direction. That is, the extending direction of the partition plate 40 and the extending direction of the second holding member 24 substantially coincide with each other. Therefore, it is possible to ensure a sufficient bonding area between the edge portion 40a of the partition plate 40 and the second holding member 24.
According to this configuration, the edge 40a of the partition plate 40 is fixed by the second holding member 24, and the base side of the partition plate 40 is fixed by the tube support plate 7, so that the partition plate 40 is fixed at two spaced locations. As a result, the partition plate 40 can be more firmly fixed.

FIG. 9 is a view showing an example of a support structure of the partition plate 40 (40A, 40B) by the annular support portion 31. As shown in FIG.
In the example shown in FIG. 9, the edge portion 40 a of the partition plate 40 is loosely fitted in the recess portion 25 a provided in the restriction member 25 of the annular support portion 31. Specifically, the regulating member 25 of the annular support portion 31 has a recess 25a, and the edge 40a of the partition plate 40 is sandwiched between the recess 25a with a predetermined gap. The interval between the regulating member 25 and the edge 40 a of the partition plate 40 may be smaller than the interval between the annular support portion 31 and the plurality of heat transfer tubes 3 of the U bend portion 20.
According to this configuration, the edge portion 40a of the partition plate 40 is formed in the concave portion 25a of the restriction member 25 of the annular support portion 31 supported on the inner wall of the steam generator 1 (for example, the inner wall of the trunk portion 2 or the tube group outer tube 9). As a result, the load can be transmitted to the inner wall side of the steam generator 1 via the partition plate 40 and the annular support portion 31 when the heat transfer tube 3 is shaken. Thereby, the load support capability of the bending part 6 resulting from the shaking of the heat exchanger tube 3 can be improved. Further, since the partition plate 40 is loosely fitted to the annular support portion 31, heat caused by a difference in thermal expansion between the inner wall of the steam generator 1 or the annular support portion 31 and the support member (partition plate) 40. Stress can be released.

In addition to the above configuration, the partition plate 40 (40A, 40B) may further include the configuration shown in FIG. 10A or 10B.
FIG. 10A is a partial cross-sectional view showing a configuration example of the partition plate 40 (40A, 40B).
As shown in the figure, the partition plate 40 is provided with at least one opening 40b. The space formed by the opening 40 b may have a columnar shape with the same shape in the thickness direction of the partition plate 40. For example, when the space formed by the opening 40b is cylindrical, the diameter of the opening 40b is the same in the thickness direction of the partition plate 40. Further, a plurality of openings 40 b may be provided for one partition plate 40.
According to this configuration, since the secondary cooling water (including steam) flows along the out-of-plane direction through the opening 40b of the partition plate 40, the partition plate 40B inhibits the heat flow in the U bend portion 20. This can be suppressed.

FIG. 10B is a partial cross-sectional view showing another configuration example of the partition plate 40 (40A, 40B).
As shown in the figure, the partition plate 40 is provided with at least one opening 40b. The opening 40b has an orifice portion 40c having a minimum opening diameter. In the illustrated configuration example, the orifice portion 40 c is located in the center portion of the partition plate 40 in the thickness direction. The wall surface of the opening 40b is formed in a tapered shape from the orifice portion 40c toward each surface of the partition plate 40, and the opening 40b increases in diameter from the central portion toward the surface in the thickness direction of the partition plate 40. doing. In another configuration example, the orifice portion 40 c may be located in any surface of the partition plate 40.
According to this configuration, when the partition plate 40 is about to be displaced in the out-of-plane direction, the displacement of the partition plate 40 is suppressed by the resistance force of the secondary cooling water (including steam) that passes through the orifice portion 40c of the opening 40b. can do.

In another embodiment, as shown in FIGS. 11A and 11B, the support member 50 extends in the horizontal direction along the out-of-plane direction or the in-plane direction, and the inner wall (for example, the trunk portion 2) of the steam generator 1. Or at least one horizontal support rod 50A, 50B supported at both ends by the inner wall of the tube group outer tube 9). In this case, as shown in FIG. 11A, the arrangement defect portion 72 is formed so that the arrangement of the heat transfer tubes 3 is such that at least a linear space is formed inside the U-bend portion 20. The horizontal support bar 50 may be rigidly fixed to the inner wall of the steam generator 1 by bolt fastening or welding. Alternatively, the horizontal support bar 50 may be supported on the inner wall of the steam generator 1 so that a difference in thermal expansion between the inner wall of the steam generator 1 and the horizontal support bar 50 can be allowed. For example, the horizontal support bar 50 is supported so as to be slightly movable with respect to the inner wall of the steam generator 1 in the extending direction of the horizontal support bar 50.
According to this configuration, when the heat transfer tube 3 shakes in the out-of-plane direction, the bent portion 6 abuts on the horizontal support rod 50 and its movement is restricted. In addition, since the horizontal support bar 50 has a relatively small projected area in the in-plane direction, the influence of the horizontal support bar 50 on the heat flow along the out-of-plane direction can be reduced.

Both ends of the horizontal support rod 50 may be supported by the annular support portion 31 (31A, 31B). The annular support portions (31A, 31B) are the same as those shown in FIGS.
In the illustrated example, the two horizontal support bars 50A and 50B are arranged along the out-of-plane direction so as to be parallel to each other in the space formed by the arrangement defect portions 72A and 72B. However, the number of horizontal support bars 50 is not limited to two, and may be one or three or more. Moreover, you may arrange | position so that it may extend along the in-plane direction of the horizontal support bar | burr 50. FIG.
According to the above configuration, both ends of the horizontal support rod 50 are supported by the annular support portion 31 that is rigidly supported on the inner wall of the steam generator 1 (for example, the inner wall of the body 2 or the tube group outer tube 9). As a result, the load supporting ability of the bent portion 6 due to the shaking of the heat transfer tube 3 can be improved.

  In still another embodiment, as shown in FIGS. 12A to 12C, the support member 60 is provided along the in-plane direction and has at least one curved support rod 60 </ b> A having higher rigidity than the bent portion 6. , 60B. The regular array 70 includes discrete defect portions 72 that are positioned discretely, and the curved support rods 60 (60 </ b> A, 60 </ b> B) are provided in at least a part of the space formed by the defective array portions 72. In the illustrated example, a plurality of curved support bars 60A and 60B are provided at different positions in the in-plane direction and the out-of-plane direction.

  According to this configuration, when the heat transfer tube 3 sways in the out-of-plane direction, the bent portion 6 abuts on the curved support rod 60 having higher rigidity than the bent portion 6 and its movement is restricted. In addition, since the curved support rod 60 has a relatively small projected area onto the plane including the bent portion 6, the influence of the curved support rod 60 on the heat flow along the out-of-plane direction can be reduced. Further, in the above configuration, since the number of the heat transfer tubes 3 to be excluded from the regular array 70 in order to form the alignment defect portion 72 can be reduced, it is possible to suppress a decrease in heat transfer efficiency due to the alignment defect portion 72.

The curved support rod 60 may have the same diameter as the heat transfer tube 3 and may be solid.
Thereby, when supporting the curved support rod 60, the same support structure as the heat transfer tube 3 can be used. For example, when the heat transfer tube 3 is supported by the tube support plate 7 configured to penetrate the heat transfer tube 3, the curved support rod 60 is supported by penetrating the tube support plate 7 in the same manner as the heat transfer tube 3. Can do.

FIG. 13 is a partial side view showing a configuration example of the curved support rod 60.
As shown in FIG. 13, the plurality of curved support bars 60 may be connected to each other. That is, a plurality of curved support bars 60 (three in the illustrated example) are arranged adjacent to each other, and these curved support bars 60 are connected to each other by the connecting member 62. In this case, the plurality of curved support bars 60 may be arranged in the out-of-plane direction or in the in-plane direction.
According to this configuration, since the plurality of curved support bars 60 are connected to each other, the rigidity of the curved support bars 60 can be increased. That is, the load supporting ability of the bent portion 6 due to the shaking of the heat transfer tube 3 can be improved.

FIG. 14 is a partial side view showing another configuration example of the curved support rod 60.
As shown in FIG. 14, the curved support rod 60 may be a bent portion of at least one high-rigidity heat transfer tube having a tube thickness or a tube diameter larger than that of the heat transfer tube 3. In the illustrated example, the curved support rod 60 constituted by the bent portion of the high-rigidity heat transfer tube has a larger diameter than the heat transfer tube 3 and is attached to the tube support plate 7 by bolts 63.
According to this configuration, the load of the bent portion 6 due to the shaking of the heat transfer tube 3 can be supported by the bent portion (curved support rod 60) of the high-rigidity heat transfer tube, and primary cooling is performed in the high-rigidity heat transfer tube. By flowing water, it is possible to further suppress a decrease in heat transfer efficiency due to the arrangement defect portion 72.

  Here, with reference to FIG. 15A and FIG. 15B, the modification of other embodiment shown to the above-mentioned FIG. 12A and FIG. 12B is demonstrated. FIG. 15A is a cross-sectional view showing a U-bend portion provided with an earthquake-resistant structure according to a modification of another embodiment. 15B is a cross-sectional view (EE cross section) of the U-bend portion shown in FIG. 15A.

As shown in FIGS. 15A and 15B, the bending support rod 60 is viewed from the hollow bending tube portion 65 provided in a plane parallel to the plane including the bending portion 6 (in-plane direction), and at least from the out-of-plane direction. The filling member 66 of the hollow bending tube portion 65 that sometimes intersects with the anti-vibration member 22 includes a filling member 66 provided inside the hollow bending tube portion 65.
In the said structure, the anti-vibration member 22 is provided between the bending parts 6 of the heat exchanger tube 3 adjacent in an out-of-plane direction for the purpose of suppressing the fluid excitation vibration in the bending part 6. FIG. When such a configuration is provided, when vibration (for example, an earthquake or the like) occurs in the U-bend portion 20, a load caused by the shaking of the heat transfer tube 3 in the out-of-plane direction is caused to pass through the anti-vibration member 22. It is transmitted between the bent portions 6 of the heat transfer tubes 3 adjacent in the outer direction. When only the hollow heat transfer tube 3 is arranged in a region intersecting with the anti-vibration member 22, the heat transfer tube 3 is crushed by the load transmitted through the anti-vibration member 22 to suppress the vibration of the entire U bend portion 20. It may not be possible.

  Therefore, in the above configuration, the curved support rod 60 having higher rigidity than the bent portion 6 is provided as a support member, and the curved bent rod 60 is provided in a plane parallel to the plane including the bent portion 6. And a filling member 66 provided inside the hollow curved tube portion 65 in the filling member 66 intersecting with the anti-vibration member 22. That is, in the filling member 66 of the hollow curved tube portion 65 that intersects with the anti-vibration member 22, since the filling member 66 is packed inside the hollow curved tube portion 65, the rigidity is higher than that of the hollow heat transfer tube 3. . Since the load resulting from the out-of-plane vibration of the heat transfer tube 3 mainly acts on the filling member 66 of the hollow bending tube portion 65 having high rigidity, the load can be received without the hollow bending tube portion 65 being crushed. Therefore, the earthquake resistance of the U bend part 20 can be improved.

In the example shown in FIG. 15B, the lower annular support portion 31 </ b> A and the upper annular support portion 31 </ b> B are provided at two different locations in the height direction, respectively on the inlet side and the outlet side of the bent portion 6 of the heat transfer tube 3. A V-shaped bracing member 22 is arranged. In this configuration, there are four filling members 66 where one hollow bending tube portion 65 intersects with the anti-vibration member 22. In these four filling members 66, the filling member 66 is provided inside the hollow bending tube portion 65.
Further, the heat transfer tube 3 may be used as the hollow bending tube portion 65. That is, a filling member 66 may be provided inside the heat transfer tube 3 to form a support member (curved support rod 60). Thereby, earthquake-proof construction can be easily performed with respect to the existing steam generator 1.

As shown in FIG. 15A, when a plurality of curved support rods 60 and a plurality of bracing members 22 are alternately arranged in the out-of-plane direction, the filling member of the hollow curved tube portion 65 arranged in the out-of-plane direction. 66, the filling member 66 in the filling member 66, and the anti-vibration member 22 may form a load transmission path that penetrates the U-bend portion 20 in the out-of-plane direction. In the illustrated example, the plurality of filling members 66 provided in the plurality of hollow curved tube portions 65 are linearly arranged at the same height as the annular support portion 31 in the out-of-plane direction. Therefore, the load transmission path is formed linearly in the order of the annular support portions 31, the alternately arranged filling members 66 and the anti-vibration members 22, and the annular support portions 31.
According to this configuration, since the load transmission path is formed by the reinforcing region of the hollow curved tube portion, the filling member 66 in the reinforcing region, and the anti-vibration member 22, Then, the rigidity in the load transmission direction can be increased. Therefore, the earthquake resistance of the U bend part 20 can be improved effectively.

As shown in FIGS. 15A and 15B, the curved support rod 60 or the anti-vibration member 22 is loosely fitted in the recess 25a (see FIG. 9) of the regulating member 25 of the annular support portion 31 at both ends of the load transmission path. May be.
According to this configuration, since the curved support rod 60 or the anti-vibration member 22 is loosely fitted in the concave portion 25a of the annular support portion 31 supported on the inner wall of the steam generator 1, the curved annular support portion 31 and the curved support portion 31 are curved. The load from the load transmission path can be received by the inner wall of the steam generator 1 while releasing the stress caused by the difference in thermal expansion with the support rod 60 or the anti-vibration member 22.

FIG. 16 is a diagram for explaining a seismic reinforcement method for a steam generator according to an embodiment. 17A is a cross-sectional view illustrating a configuration example of the filling member, and FIG. 17B is a cross-sectional view taken along line FF in FIG. 17A.
The filling member 66 may be configured by a plurality of sections provided in a cross section along the tube length direction of the hollow curved tube portion 65. As shown in FIG. 17A, this cross section is a cross section including a reinforcing region of the hollow bending tube portion 65 and a pair of anti-vibration members 22 located on both sides of the reinforcing region. In the example shown in FIGS. 16, 17A, and 17B, each of the plurality of filling members 66 includes two sections 66A and 66B arranged in the out-of-plane direction. In FIG. 16, each filling member 66 is arranged so that two sections 66A and 66B overlap in the depth direction of the paper surface. Therefore, the section 66A on the front side of the paper surface is indicated by a solid line, and the section on the back side of the paper surface. 66B is indicated by a dotted line.
According to this configuration, since the filling member 66 is formed by a divided structure including a plurality of sections 66A and 66B, each of the sections 66A and 66B of the filling member 66 on the load transmission path along the out-of-plane direction. It is possible to prevent a gap from being formed between the inner wall surface of the hollow bending tube portion 65. Thereby, crushing of the hollow bending tube part 65 can be prevented, and vibration of the entire U bend part 20 can be effectively suppressed.

Further, the curved support rod 60 may be formed by installing a filling member 66 inside some of the heat transfer tubes 3.
According to this structure, earthquake-proof construction can be easily performed on the existing steam generator 1.

Here, with reference to FIG. 16, FIG. 17A and FIG. 17B, the seismic reinforcement method of the steam generator 1 which concerns on one Embodiment is demonstrated below.
In one embodiment, the seismic reinforcement method of the steam generator 1 includes an installation step of installing in the steam generator 1 a support member 60 for restricting the movement of the plurality of heat transfer tubes 3 in the out-of-plane direction.
In the steam generator 1, a plurality of bent portions 6 having different curvature radii are arranged along an in-plane direction parallel to the plane, and a plurality of bent portions 6 having the same curvature radius are arranged in an out-of-plane direction. The plurality of through-holes 71 through which the first straight pipe portion 4 and the second straight pipe portion 5 of the plurality of heat transfer tubes 3 pass are regularly arranged 70 (FIGS. 5A, 6A, 10A and (See FIG. 11A). In the installation step, the support members 60 are installed in place of the heat transfer tubes 3 in at least one row along the in-plane direction or the out-of-plane direction in the regular array 70.

According to the above method, when the heat transfer tube 3 is shaken in the out-of-plane direction, the bent portion 6 abuts on the support member 60 and further displacement is prevented, so that the displacement of the bent portion 6 is kept small. be able to. Therefore, the shaking in the bending part 6 of the heat exchanger tube 3 can be suppressed, and the earthquake resistance of the steam generator 1 can be improved.
In addition, since the support members 60 are installed in place of the heat transfer tubes 3 in at least one row along the in-plane direction or the out-of-plane direction among the regular array 70 of the plurality of heat transfer tubes 3, the existing steam generator 1 Can be easily seismic-proofed.

In the installation step, at least one curved support rod 60 provided along the in-plane direction and having higher rigidity than the bent portion 6 may be installed as a support member.
When the heat transfer tube 3 swings in the out-of-plane direction, the bent portion 6 abuts on the curved support rod 60 having higher rigidity than the bent portion 6 and its movement is restricted. Can be suppressed. Further, since the curved support rod 60 has a relatively small projected area on the surface including the bent portion 6, the influence of the curved support rod 60 on the heat flow along the out-of-plane direction can be reduced.
Further, in the installation step, the curved support rod 60 may be formed by providing the filling member 66 inside the reinforcement target heat transfer tube 60 ′ which is a part of the plurality of heat transfer tubes 3.
According to this, since it is not necessary to remove a part of the heat transfer tube 3 when installing the support member 60 in the existing steam generator 1, it is easy to perform earthquake-proof construction on the existing steam generator 1. Can do.

In another embodiment, when the steam generator 1 includes the above-described anti-vibration member 22 illustrated in FIGS. 2 and 3, in the installation step, the reinforcement object that intersects with the anti-vibration member 22 when viewed from the out-of-plane direction. In the reinforcing region 68 of the heat transfer tube 60 ′, filling members 66 (66-1, 66-2, 66-3, 66-4) are provided inside the heat transfer target tube 60 ′. The filling members 66-1, 66-2, 66-3, 66-4 may have the same configuration as the filling member 66 shown in FIGS. 17A and 17B.
According to this method, in the reinforcement region 68 ′ of the reinforcement target heat transfer tube 60 ′ intersecting with the anti-vibration member 22, the filling member 66 (66-1, 66-2, 66− is provided inside the reinforcement target heat transfer tube 60 ′. 3, 66-4) is packed, so that the rigidity is higher than that of the hollow heat transfer tube 3. Since the load caused by the vibration component in the out-of-plane direction mainly acts on the reinforced region 68 ′ of the reinforced object heat transfer tube 60 ′ having high rigidity, the load can be received without being crushed. Therefore, the earthquake resistance of the U bend part 20 can be improved.

A plurality of curved support rods 60 and a plurality of bracing members are alternately arranged in the out-of-plane direction,
In the installation step, the reinforcement region 68 ′ of the heat transfer tubes 60 ′ to be reinforced arranged in the out-of-plane direction, the filling members 66 (66-1, 66-2, 66-3, 66-4) in the reinforcement region 68 ′, And the load transmission path which penetrates the U-bend part 20 in an out-of-plane direction is formed by the anti-vibration member 22.
According to this method, the reinforcing region 68 ′ of the heat transfer tube 60 ′ to be reinforced, the filling member 66 (66-1, 66-2, 66-3, 66-4) in the reinforcing region 68 ′, and the anti-rest Since the load transmission path is formed by the member 22, the rigidity of the U-bend portion 20 in the out-of-plane direction can be increased. Therefore, the earthquake resistance of the U bend part 20 can be improved effectively.

For example, the filling member 66 (66-1, 66-2, 66-3, 66-4) may be installed at a predetermined position in the heat transfer tube 60 ′ to be reinforced by wires 80A and 80B.
Specifically, as shown in FIGS. 16, 17A, and 17B, the filling member 66 (66-1, 66-2, 66-3, 66-4) is installed for each reinforcing region 68 ′. Each filler member 66 (66-1,66-2,66-3,66-4) includes a first section _{66A (66A 1, 66A 2,} 66A 3, 66A 4), second section 66B _(66B 1, 66B ₂ , 66B ₃ , 66B ₄ ). The first section 66A and the second section 66B have tapered surfaces that are inclined with respect to the tube length direction, and are arranged in a state where the tapered surfaces contact each other. The tapered surface of the first section 66A and the tapered surface of the second section 66B have the same inclination angle with respect to the tube length direction. The surfaces of the first section 66A and the second section 66B opposite to the tapered surfaces are formed along the tube wall of the heat transfer tube 60 ′ to be reinforced. Therefore, when the relative positions in the tube length direction of the first section 66A and the second section 66B change, the integral width (width in the tube diameter direction) of the first section 66A and the second section 66B changes. The tapered surface may be a flat surface or a surface having irregularities in the tube length direction, and the positions of the first section 66A and the second section 66B in the tube length direction may be maintained.

Each first section 66A (66A ₁ , 66A ₂ , 66A ₃ , 66A ₄ ) is connected to each other by a wire 80A in a state of being separated from each other. Similarly, the second sections 66B (66B ₁ , 66B ₂ , 66B ₃ , 66B ₄ ) are connected to each other in a state of being separated from each other by a wire 80B. A first member 82 having an L-shaped cross section is attached to the end of the wire 80A. On the other hand, a second member 84 is attached to the end of the wire 80B. The second member 84 is configured such that the bottom surface is pushed by the first member 82 and moves together with the first member 82 in one direction.

  When the filling member 66 (66-1, 66-2, 66-3, 66-4) is installed in the above configuration, first, the wire 80A to which the first section 66A is attached and the second section 66B are attached. The wire 80B is inserted into the reinforcement target heat transfer tube 60 ′. Then, with the second member 84 placed on the first member 82, the wire 80A and the wire 80B are pushed into the reinforcement target heat transfer tube 60 'from the bottom surface of the first member 82 by a pusher (not shown). Then, the filling member 66 (66-1, 66-2, 66-3, 66-4) is moved to a predetermined reinforcing region 68 '. In addition, in the state where each filling member 66 is located in the predetermined reinforcing region 68 ′, the wire 80A extending from the first section 66A1 farthest from the first member 82 protrudes from the heat transfer pipe 60 ′ to be reinforced. The length of 80A is adjusted in advance.

  When each filling member 66 is located in a predetermined reinforcing region 68 ', the wire 82A protruding from the heat transfer tube 60' to be reinforced is pulled to move only the first section 66A slightly. Thereby, the integral width (width in the tube radial direction) of the first section 66A and the second section 66B is expanded, and the first section 66A and the second section 66B are pressed against the tube wall of the heat transfer tube 60 'to be reinforced. Therefore, the filling member 66 is packed in the reinforcing heat transfer tube 60 ′ without any gap in the load transmission path. Thereafter, the end of the heat transfer tube 60 ′ to be reinforced may be sealed with a plug 88.

  Further, a position sensor 87 for detecting the position of at least one filling member 66 (66-1, 66-2, 66-3, 66-4) may be attached. By moving the wires 82 </ b> A and 82 </ b> B based on the detection signal from the position sensor 87, each filling member 66 can be appropriately installed in a predetermined reinforcing region 68 ′. In the illustrated example, the position sensor 87 is attached to the wires 80 </ b> A and 80 </ b> B in the vicinity of the filling member 66. In the illustrated example, the position sensors 87 are attached to all of the filling members 66-1, 66-2, 66-3, 66-4, but the filling members 66-1, 66-2, 66 are provided. If the distance between −3 and 66-4 is acquired in advance, the number of position sensors 87 may be one. Further, the position sensor 87 may be removable after the filling member 66 is installed.

  In the above description, the example in which the filling member 66 is configured by the two sections 66A and 66B has been described. However, in order to facilitate handling during installation, the filling member 66 may be configured by one section. In addition, after the filling member 66 is installed, the end portion of the reinforcement target heat transfer tube 60 ′ may not be sealed with the plug 88, and water may flow inside the reinforcement target heat transfer tube 60 ′.

FIG. 19 is a side view showing another configuration example of the filling member 66.
In the example shown in the figure, the filling member 66 includes a main body portion 90 and an insertion portion 95 inserted into the main body portion 90.
The main body portion 90 is formed in a truncated cone shape on the small diameter side and formed in a cylindrical shape on the large diameter side, and has a substantially truncated cone-shaped recess portion 91 provided on the surface on the large diameter side, and a female screw portion communicating with the recess portion 91. 92. A slit 93 extending along the tube length direction is provided on the outer periphery on the large diameter side of the main body 90. A plurality of slits 93 may be provided in the circumferential direction of the main body 90.
The insertion portion 95 includes a truncated cone portion 96 having an outer peripheral surface having a shape corresponding to the concave portion 91 of the main body portion 90, and a male screw portion 97 formed corresponding to the female screw portion 92 of the main body portion 90. .

In the above configuration, the filling member 66 is inserted into the heat transfer tube 60 ′ to be reinforced, moved to the reinforced region 68 ′, and then the insertion portion 95 is rotated in the circumferential direction by the torque transmission wire 99. The male screw portion 97 is screwed into the female screw portion 92 of the main body portion 90. At this time, the truncated cone portion 96 of the insertion portion 95 is pushed into the concave portion 91 of the main body portion 90, the slit 93 is opened, and the main body portion 90 is expanded in diameter. As a result, the outer peripheral surface of the main body 90 is pressed against the tube wall of the reinforcement target heat transfer tube 60 ', and the filling member 66 is packed in the load transfer path without any gaps in the reinforcement target heat transfer tube 60'.
As another configuration example, the main body 90 and the insertion portion 95 are formed of materials having different linear expansion coefficients, and the outer peripheral surface of the main body 90 is pressed against the tube wall of the heat transfer tube 60 ′ to be reinforced by temperature change. You may do it.

FIG. 20 is a side view showing still another configuration example of the filling member 66.
In the example shown in the figure, the filling member 66 includes a first pedestal portion 101, a first gear portion 102, a second pedestal portion 103, a second gear portion 104, and a third gear portion 105.
The first pedestal portion 101 is formed so as to abut against the inner wall surface on one side of the heat transfer tube 60 ′ to be reinforced, and the second pedestal portion 103 is opposed to the inner wall surface with which the first pedestal portion 101 abuts. It forms so that it may contact | abut to the inner wall surface of the side.
The first gear portion 102, the second gear portion 104, and the third gear portion 105 are constituted by bevel gears. The first gear portion 102 is rotatably supported by the first pedestal portion 101. The second gear portion 104 is rotatably supported by the second pedestal portion 103. The third gear portion 105 is detachably attached to the torque transmission wire 106 and is provided so as to mesh with the first gear portion 102 and the second gear portion 104.

  In the above configuration, the filling member 66 is inserted into the reinforcement target heat transfer tube 60 ′ and moved to the reinforcement region 68 ′, and then the third gear portion 105 is moved by the torque transmission wire 106 in the circumferential direction of the reinforcement target heat transfer tube 60 ′. Rotate to Accordingly, the first gear portion 102 and the second gear portion 104 meshed with the third gear portion 105 rotate in the direction of the arrow in the drawing. Note that a rotation stop structure may be further provided so that the first pedestal portion 101 and the second pedestal portion 103 do not rotate due to the rotation of the first gear portion 102 and the second gear portion 104. For example, since the first pedestal portion 101 and the second pedestal portion 103 are reversely rotated, the first pedestal portion 101 and the second pedestal portion 103 may be configured to prevent relative rotation. It is good also considering the surface which touches the reinforcement object heat exchanger tube 60 'of the part 101 and the 2nd base part 103 as a friction surface.

  As described above, according to the above-described embodiment, when the heat transfer tube 3 is shaken in the out-of-plane direction due to an earthquake or the like, the bent portion 6 of the heat transfer tube 3 contacts the support members 40, 50, 60. Since the further displacement is prevented, the displacement of the bent portion 6 can be kept small. Therefore, the vibration in the bent part of the heat transfer tube can be suppressed, and the earthquake resistance of the steam generator 1 can be improved.

Moreover, the following advantages are acquired by applying the above-mentioned embodiment to a nuclear power plant. Here, the nuclear power plant according to an embodiment is configured to be driven by a reactor vessel (eg, a pressurized water reactor) configured to heat the primary coolant and steam of the secondary coolant. A steam turbine and the steam generator 1 described in the above embodiment are provided.
According to the nuclear power plant, the vibration at the bent portion 6 of the heat transfer tube 3 can be suppressed, and the seismic performance of the steam generator 1 can be improved. Therefore, a highly reliable nuclear power plant can be provided.

  The present invention is not limited to the above-described embodiments, and includes forms obtained by modifying the above-described embodiments and forms obtained by appropriately combining these forms.

For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expression “comprising”, “including”, or “having” one constituent element is not an exclusive expression that excludes the presence of the other constituent elements.

DESCRIPTION OF SYMBOLS 1 Steam generator 2 Trunk part 3 Heat exchanger tube 4 1st straight pipe part 5 2nd straight pipe part 6 Bending part 7 Pipe support plate 20 U bend part 21 1st holding member 22 Anti-vibration member 24 2nd holding member (bridge)
25 Restriction member 25a Recess 31 (31A, 31B) Ring support portion 32 (32A, 32B) Arm-like support portion 33 Outer cylinder support portion 40 (40A, 40B) Support member (partition plate)
50 (50A, 50B) Support member (horizontal support bar)
60 (60A, 60B), support member (curved support bar)
60 'support member (heat transfer tube to be reinforced)
66 (66-1,66-2,66-3,66-4) filling member _{66A (66A 1, 66A 2,} 66A 3, 66A 4) first section _{66B (66B 1, 66B 2,} 66B 3, 66B 4 ) Second section 68, 68 'Reinforcement region 70 Regular arrangement 71 Through hole 72 (72A, 72B) Arrangement defect part 80A, 80B Wire

Claims (24)

A steam generator for generating steam by heat exchange with a fluid flowing in a heat transfer pipe,
A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bend located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes each having a portion;
A tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted;
A support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction orthogonal to a plane including the bent portion,
The plurality of heat transfer tubes such that a plurality of the bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and a plurality of the bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion pass are arranged according to a regular arrangement in a top view of the pipe support plate,
It said regular sequence comprises a sequence defect portion in which the heat transfer tubes are not present in at least one row along the plane Direction,
The support member is provided in the alignment defect portion ,
The support member includes at least one partition plate fixed to the tube support plate and provided along the in-plane direction between the plurality of bent portions.
A holding member provided along the outer shape of a hemispherical U-bend portion formed above the tube support plate by the bent portions of the plurality of heat transfer tubes;
A plurality of anti-vibration members provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction and extending inward in the radial direction of the hemispherical shape of the U-bend portion from the holding member; Further comprising
The partition plate is sandwiched from both sides by the plurality of anti-vibration members,
The partition plate has an arc-shaped edge along the outer shape of the U-bend portion,
The steam generator, wherein the edge is fixed to the holding member . An annular support portion supported on the inner wall of the steam generator and surrounding the U-bend portion;
Steam generator according to claim 1, characterized in that the edge of the partition plate in a recess provided in said annular support portion is loosely fitted. The steam generator according to claim 1 or 2 , wherein at least one opening is provided in the partition plate. The steam generator according to claim 3 , wherein the opening has an orifice portion having a minimum opening diameter. Wherein the at least one partition plate, according to any one of claims 1 to 4, characterized in that it comprises a plurality of partition plates provided along the plane direction so as to be aligned in the out of plane direction Steam generator. A steam generator for generating steam by heat exchange with a fluid flowing in a heat transfer pipe,
A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bend located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes each having a portion;
A tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted;
A support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction orthogonal to a plane including the bent portion,
The plurality of heat transfer tubes such that a plurality of the bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and a plurality of the bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion pass are arranged according to a regular arrangement in a top view of the pipe support plate,
The regular arrangement includes an arrangement defect portion in which the heat transfer tubes do not exist in at least one row along the in-plane direction,
The support member is provided in the alignment defect portion,
The support member is provided along the plane direction, and, steam generator you wherein a rigidity than the bent portion comprises a high least one curved support bars. The steam generator according to claim 6 , wherein the curved support rod has the same diameter as the heat transfer tube and is solid. Further comprising at least one high-rigidity heat transfer tube having a tube thickness or a tube diameter larger than that of the heat transfer tube,
The steam generator according to claim 6 , wherein the curved support rod is a bent portion of the high-rigidity heat transfer tube. The steam generator according to any one of claims 6 to 8 , wherein the plurality of curved support rods are connected to each other. The bent portions of the plurality of heat transfer tubes form a hemispherical U-bend portion above the tube support plate;
A plurality of bracing members provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction and extending along the radial direction of the hemispherical shape of the U-bend portion;
The curved support rod is
A hollow curved pipe provided in a plane parallel to the plane;
At least in a reinforcing region of the hollow curved tube portion that intersects the anti-vibration member when viewed from the out-of-plane direction, a filling member provided inside the hollow curved tube portion;
The steam generator according to claim 6, 8, or 9 . A plurality of the curved support rods and a plurality of the bracing members are alternately arranged in the out-of-plane direction,
A load transmission path that penetrates the U-bend portion in the out-of-plane direction by the reinforcing region of the hollow curved tube portions arranged in the out-of-plane direction, the filling member in the reinforcing region, and the anti-vibration member. The steam generator according to claim 10 , wherein the steam generator is formed. An annular support portion supported on the inner wall of the steam generator and surrounding the U-bend portion;
The steam generator according to claim 11 , wherein the curved support rod or the anti-vibration member is loosely fitted in a recess provided in the annular support portion at both ends of the load transmission path. The filling member includes a plurality of sections provided in a cross section along the tube length direction of the hollow curved tube portion including the reinforcing region of the hollow curved tube portion and a pair of the anti-vibration members located on both sides of the reinforcing region. The steam generator according to any one of claims 10 to 12 , wherein the steam generator is constituted by a section. The steam generator according to any one of claims 10 to 13 , wherein the curved support rod is formed by installing the filling member inside a part of the heat transfer tubes. A steam generator for generating steam by heat exchange with a fluid flowing in a heat transfer pipe,
A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bend located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes each having a portion;
A tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted;
A support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction orthogonal to a plane including the bent portion,
The plurality of heat transfer tubes such that a plurality of the bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and a plurality of the bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion pass are arranged according to a regular arrangement in a top view of the pipe support plate,
The regular arrangement includes an arrangement defect portion in which the heat transfer tubes do not exist in at least one row along the out-of-plane direction,
The support member is provided in the alignment defect portion,
Said support member extends in a horizontal direction along the surface outward direction, steam generated across the inner wall of the steam generator you comprising a horizontal supporting bar of the at least one supported vessel. A steam generator for generating steam by heat exchange with a fluid flowing in a heat transfer pipe,
A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bend located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes each having a portion;
A tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted;
A support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction orthogonal to a plane including the bent portion,
The plurality of heat transfer tubes such that a plurality of the bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and a plurality of the bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion pass are arranged according to a regular arrangement in a top view of the pipe support plate,
The regular arrangement includes an arrangement defect portion in which the heat transfer tubes do not exist in at least one row along the in-plane direction or the out-of-plane direction,
The support member is provided in the alignment defect portion,
The support member includes at least one horizontal support bar that extends in the horizontal direction along the out-of-plane direction or the in-plane direction and is supported at both ends by the inner wall of the steam generator;
An annular support portion that is supported on the inner wall of the steam generator and surrounds a hemispherical U-bend portion formed above the tube support plate by the bent portions of the plurality of heat transfer tubes;
Wherein the ends of at least one of the horizontal support bar, steam generator you characterized in that it is supported by the annular supporting portion. A reactor vessel configured to heat the primary coolant;
A steam turbine configured to be driven by the steam of the secondary coolant;
The steam generator according to any one of claims 1 to 16 , wherein the steam generator is configured to generate the steam of the secondary coolant by heat exchange with the primary coolant.
A nuclear plant characterized by comprising: A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bent portion located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes, and a tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted. A method for seismic reinforcement of a steam generator for generating steam by heat exchange with the fluid flowing in the heat transfer pipe,
An installation step of installing in the steam generator a support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction perpendicular to the plane including the bent portion;
In the steam generator, the plurality of bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and the plurality of bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion of the plurality of heat transfer tubes pass are arranged according to a regular arrangement in a top view of the tube support plate,
In the installation step,
In at least one row along the Direction within the plane of the ordered array, instead of the heat transfer tube, arranged along the plane direction, and said at least one stiffer than curved portion curved support A method for seismic reinforcement of a steam generator, characterized in that a rod is installed as the support member. 19. The steam generator according to claim 18 , wherein, in the installation step, the curved support rod is formed by providing a filling member inside a heat transfer tube to be reinforced that is a part of the plurality of heat transfer tubes. Seismic reinforcement method. The bent portions of the plurality of heat transfer tubes form a hemispherical U-bend portion above the tube support plate;
The steam generator is provided between the bent portion of the heat transfer tubes that are adjacent in the out of plane direction, a plurality of vibration stopper member extending along the radial direction of the hemispherical shape of the U-bend portion In addition,
In the installation step,
In reinforcing the region of the reinforcement subject heat transfer tube intersecting the vibration preventing member when viewed from the surface outward, according to claim 19, characterized in that providing the filling member to the inside of the reinforcing target heat transfer tube Seismic reinforcement method for steam generators. A plurality of the curved support rods and a plurality of the bracing members are alternately arranged in the out-of-plane direction;
In the installation step, the U-bend portion is penetrated in the out-of-plane direction by the reinforcement region of the heat transfer tubes to be reinforced arranged in the out-of-plane direction, the filling member in the reinforcement region, and the anti-vibration member. 21. The method for seismic reinforcement of a steam generator according to claim 20 , wherein a load transmission path is formed. A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bent portion located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes, and a tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted. A method for seismic reinforcement of a steam generator for generating steam by heat exchange with the fluid flowing in the heat transfer pipe,
An installation step of installing in the steam generator a support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction perpendicular to the plane including the bent portion;
In the steam generator, the plurality of bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and the plurality of bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion of the plurality of heat transfer tubes pass are arranged according to a regular arrangement in a top view of the tube support plate,
The bent portions of the plurality of heat transfer tubes form a hemispherical U-bend portion above the tube support plate;
The steam generator
A holding member provided along the outer shape of a hemispherical U-bend portion formed above the tube support plate by the bent portions of the plurality of heat transfer tubes;
A plurality of anti-vibration members provided between the bent portions of the heat transfer tubes adjacent in the out-of-plane direction and extending inward in the radial direction of the hemispherical shape of the U-bend portion from the holding member;
Have
In the installation step,
In at least one row along the in-plane direction of the regular array, a partition plate as the support member extending along the in-plane direction between the plurality of bent portions instead of the heat transfer tube While fixing to the tube support plate,
An edge of the arc-shaped partition plate along the outer shape of the U-bend portion is fixed to the holding member in a state where the partition plate is sandwiched from both sides by the plurality of anti-vibration members.
A method for seismic reinforcement of steam generators. A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bent portion located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes, and a tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted. A method for seismic reinforcement of a steam generator for generating steam by heat exchange with the fluid flowing in the heat transfer pipe,
An installation step of installing in the steam generator a support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction perpendicular to the plane including the bent portion;
In the steam generator, the plurality of bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and the plurality of bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion of the plurality of heat transfer tubes pass are arranged according to a regular arrangement in a top view of the tube support plate,
In the installation step,
In at least one row along the out-of-plane direction of the regular array, instead of the heat transfer tube, it extends in the horizontal direction along the out-of-plane direction, and at least both ends are supported by the inner wall of the steam generator. One horizontal support rod is installed as the support member
A method for seismic reinforcement of steam generators. A first straight pipe portion located on the fluid inlet side; a second straight pipe portion located on the fluid outlet side; and a bent portion located between the first straight pipe portion and the second straight pipe portion. A plurality of heat transfer tubes, and a tube support plate formed with a plurality of through holes through which the first straight tube portion and the second straight tube portion of the plurality of heat transfer tubes are inserted. A method for seismic reinforcement of a steam generator for generating steam by heat exchange with the fluid flowing in the heat transfer pipe,
An installation step of installing in the steam generator a support member for restricting movement of the plurality of heat transfer tubes in an out-of-plane direction perpendicular to the plane including the bent portion;
In the steam generator, the plurality of bent portions having different curvature radii are arranged along an in-plane direction parallel to the plane, and the plurality of bent portions having the same curvature radius are arranged in the out-of-plane direction. The plurality of through-holes through which the first straight pipe portion and the second straight pipe portion of the plurality of heat transfer tubes pass are arranged according to a regular arrangement in a top view of the tube support plate,
The steam generator is supported by an inner wall of the steam generator, and an annular support portion surrounding a hemispherical U-bend portion formed above the tube support plate by the bent portions of the plurality of heat transfer tubes. Further comprising
In the installation step,
As the support member that extends in the horizontal direction along the out-of-plane direction or the in-plane direction instead of the heat transfer tube in at least one row along the out-of-plane direction or the in-plane direction of the regular array. At least one horizontal support bar
Both ends of the horizontal support rod are supported by the annular support portion.
A method for seismic reinforcement of steam generators.