JPH04204087A - Nuclear reactor - Google Patents
Nuclear reactorInfo
- Publication number
- JPH04204087A JPH04204087A JP2329037A JP32903790A JPH04204087A JP H04204087 A JPH04204087 A JP H04204087A JP 2329037 A JP2329037 A JP 2329037A JP 32903790 A JP32903790 A JP 32903790A JP H04204087 A JPH04204087 A JP H04204087A
- Authority
- JP
- Japan
- Prior art keywords
- assembly
- fuel
- fuel assembly
- rod
- socket
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000446 fuel Substances 0.000 claims abstract description 74
- 238000003780 insertion Methods 0.000 abstract description 10
- 230000037431 insertion Effects 0.000 abstract description 10
- 239000000463 material Substances 0.000 abstract description 5
- 230000009471 action Effects 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract 7
- 230000006866 deterioration Effects 0.000 abstract 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 14
- 239000002826 coolant Substances 0.000 description 7
- 230000008878 coupling Effects 0.000 description 7
- 238000010168 coupling process Methods 0.000 description 7
- 238000005859 coupling reaction Methods 0.000 description 7
- 238000009835 boiling Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005514 two-phase flow Effects 0.000 description 3
- 229910052770 Uranium Inorganic materials 0.000 description 2
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000003758 nuclear fuel Substances 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- JFALSRSLKYAFGM-UHFFFAOYSA-N uranium(0) Chemical compound [U] JFALSRSLKYAFGM-UHFFFAOYSA-N 0.000 description 2
- 244000025254 Cannabis sativa Species 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 235000015115 caffè latte Nutrition 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000004992 fission Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000003449 preventive effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Monitoring And Testing Of Nuclear Reactors (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野]
本発明は、原子炉内に設置した燃料集合体が、燃料集合
体下端から流入する冷却材の圧力で浮き上がることを防
止するための、燃料集合体結合装置に関する。[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a fuel assembly for preventing a fuel assembly installed in a nuclear reactor from floating due to the pressure of coolant flowing from the lower end of the fuel assembly. The present invention relates to an aggregate coupling device.
[従来の技術]
従来、加圧水型原子炉(PWR)では、冷却材流速が沸
騰水型原子炉(BWR)より速く、燃料集合体に加わる
揚力が大きいため、燃料集合体上端の上部ノズルに浮き
上がり防止の板ばねをとりつけ、この板ばねを上部炉心
板で押えることによって燃料集合体の浮き上がりを防止
していた。この構造については、財団法人原子力安全研
究協会、軽水炉燃料のふるまい編集委員会編の「軽水炉
燃料ノフルまい」PP59〜6o(昭60年8月)に詳
しい。[Prior Art] Conventionally, in a pressurized water reactor (PWR), the coolant flow rate is faster than that in a boiling water reactor (BWR), and the lift force applied to the fuel assembly is large, so the coolant floats up to the upper nozzle at the upper end of the fuel assembly. A preventive leaf spring was installed, and this leaf spring was pressed down by the upper core plate to prevent the fuel assembly from floating up. This structure is detailed in ``Light Water Reactor Fuel Behavior'' PP59-6o (August 1986) edited by the Nuclear Safety Research Association and the Light Water Reactor Fuel Behavior Editorial Committee.
近年、軽水炉において燃料棒を稠密に配置して、中性子
のスペクトルを硬くし、核分裂をおこしにくい°′U
をおこしやすい°”Pu に変換させて、ウラン資源
を節約する高転換型炉心の設計が進んでいる。この様な
炉心では、炉心の圧力損失が大きくなり、従来浮き上が
りに対して対策が不要であったBWRでも、揚力が増加
して、何らかの対策を施す必要が発生した。In recent years, fuel rods in light water reactors have been densely arranged to harden the neutron spectrum and make nuclear fission less likely to occur.
Progress is being made in the design of high-conversion reactor cores that conserve uranium resources by converting uranium into Pu, which is more likely to cause Even with the existing BWR, the lift force increased and it became necessary to take some countermeasures.
板ばねで上から燃料集合体を押える上記従来技術は、冷
却材が単相流であるPWRに利用されておる。単相流の
場合、集合体に浮力を発生させる集合体内圧力損失の時
間的な変動は少ない。しかし、沸騰水型原子炉では、冷
却材が気液二相流のため、圧力損失の時間変動が太きい
。その結果、燃料集合体をばねで押えている構造では、
燃料集合体が圧力変動に起因して揚力が変化し、上下に
振動する可能性がある。燃料集合体の振動は、構造材の
強度や限界出力などの熱的な特性に、悪い影響を及ぼす
。The above-mentioned conventional technique of pressing down the fuel assembly from above with a leaf spring is used in a PWR in which the coolant is a single-phase flow. In the case of single-phase flow, there is little temporal variation in the pressure drop within the assembly that generates buoyancy in the assembly. However, in a boiling water reactor, the coolant is a gas-liquid two-phase flow, so the pressure loss fluctuates widely over time. As a result, in a structure in which the fuel assembly is held down by a spring,
The fuel assembly may vibrate up and down due to changes in lift due to pressure fluctuations. Vibrations in fuel assemblies have a negative effect on thermal properties such as the strength and critical output of structural materials.
本発明の目的は、燃料集合体を剛に固定し、振動を防ぐ
とともに、中性子照射や温度変化にともなう燃料集合体
の伸びを吸収できる構造を提供する二とにある。It is an object of the present invention to provide a structure that can rigidly fix a fuel assembly, prevent vibration, and absorb elongation of the fuel assembly due to neutron irradiation or temperature changes.
[課題を解決するための手段]
上記目的を達成するために、本発明では、燃料集合体下
端及び燃料支持金具に、プラグ、ソケット等からなる結
合装置を設け、燃料集合体内に上下に操作棒を貫通させ
、燃料集合体の上側から、燃料集合体と燃料支持金具と
の着脱を可能としたものである。[Means for Solving the Problems] In order to achieve the above object, in the present invention, a coupling device consisting of a plug, a socket, etc. is provided at the lower end of the fuel assembly and the fuel support fitting, and an operating rod is installed vertically within the fuel assembly. The fuel assembly and the fuel support fitting can be attached and detached from the upper side of the fuel assembly by penetrating the fuel assembly.
[作用]
結合器は、プラグとスパッドとソケット、またはプラグ
とラッチとソケット、あるいは、溝に複数のボールをは
めこんだロッドとソケット等から成り、これらの結合器
を燃料集合体内を貫通した操作棒を使って、燃料集合体
の上側から操作する。[Operation] A coupler consists of a plug, spud, and socket, or a plug, latch, and socket, or a rod and socket with multiple balls fitted in grooves, and these couplers can be operated by penetrating the fuel assembly. Operate from the top of the fuel assembly using a rod.
結合器は、燃料集合体を原子炉下部構造物に剛に結合す
るので、二相流に起因する揚力の変動に対して、燃料集
合体が大きく上下に振動することがない。Since the coupler rigidly couples the fuel assembly to the reactor substructure, the fuel assembly will not vibrate significantly up and down in response to fluctuations in lift caused by two-phase flow.
〔実施例]
以下、本発明の一実施例を第1図及び第2図を用いて説
明する。まず、第2図は、本発明を適用する高転換型の
BWRの一例である。この原子炉は燃料棒を三角格子に
稠密に配置した、断面が六角形状の燃料集合体10をも
ち、PWRと同じくクラスタ型の制御棒8を燃料集合体
10内に下から挿入する構造をもつ。燃料集合体10の
上側には、上部炉心板13があり、燃料集合体10の位
置決めと、固定の役割を果たしている。物料集台体10
の下側には制御棒8の通路を確保する制御棒案内管12
が原子炉圧力容器19に溶接しである。制御棒駆動機構
9.インターナルポンプ1]。[Example] An example of the present invention will be described below with reference to FIGS. 1 and 2. First, FIG. 2 shows an example of a high conversion type BWR to which the present invention is applied. This reactor has a fuel assembly 10 with a hexagonal cross section in which fuel rods are densely arranged in a triangular lattice, and has a structure in which cluster-type control rods 8 are inserted from below into the fuel assembly 10, similar to PWR. . There is an upper core plate 13 above the fuel assembly 10, which plays the role of positioning and fixing the fuel assembly 10. Material collection stand 10
A control rod guide tube 12 that secures a passage for the control rods 8 is located below the
is welded to the reactor pressure vessel 19. Control rod drive mechanism9. Internal pump 1].
汽水分離器18.蒸気乾燥器17などは、既存のBWR
と同じ構造になっている。給水管31から流入した冷却
材は、原子炉圧力容器19と炉心シュラウド16との間
の円環状のダウンカマ領域を下向きに流れ、インターナ
ルポンプ11で昇圧されて燃料集合体10に下から流入
する。燃料集合体ICI内で加熱された冷却材は沸騰し
、二相流状態で汽水分離器18へ流入する。ここで蒸気
と水の二成分に分離され、蒸気は蒸気乾燥器I7を経て
主蒸気管30に流れ、水は、再び、タウンカマ領域へ流
入する。この原子炉では、稠密な燃料集合体を使用する
ため、燃料集合体10内の圧力損失が大きく、従って、
燃料集合体10に上向きにかかる揚力か大きくなり、こ
れが自重を上回ると浮き上がってします。従って、集合
体の浮き上がりを防止する機構が必要になる。Brackish water separator 18. Steam dryer 17 etc. are installed in the existing BWR.
It has the same structure. The coolant flowing from the water supply pipe 31 flows downward through the annular downcomer region between the reactor pressure vessel 19 and the core shroud 16, is pressurized by the internal pump 11, and flows into the fuel assembly 10 from below. . The coolant heated within the fuel assembly ICI boils and flows into the brackish water separator 18 in a two-phase flow state. There, it is separated into two components: steam and water, the steam flows through the steam dryer I7 to the main steam pipe 30, and the water flows again into the town cooper area. In this nuclear reactor, since a dense fuel assembly is used, the pressure loss within the fuel assembly 10 is large, and therefore,
The upward lift force applied to the fuel assembly 10 increases, and if this exceeds its own weight, it will float. Therefore, a mechanism is required to prevent the assembly from floating up.
第1図は、その浮き上がりを防止する、本発明の一実施
例である。燃料集合体10は、上部タイプレート1と下
部タイプレート7を、制御棒を通す制御棒案内シンプル
管3で固定して骨組みとじ、下部タイプレート7、スペ
ーサ6、燃料棒端栓挿入板2で燃料棒4を支持した構造
になっている。FIG. 1 shows an embodiment of the present invention that prevents this lifting. The fuel assembly 10 is constructed by fixing an upper tie plate 1 and a lower tie plate 7 with a simple control rod guide tube 3 through which the control rods pass, and then forming a frame with a lower tie plate 7, a spacer 6, and a fuel rod end plug insertion plate 2. It has a structure that supports fuel rods 4.
燃料集合体10の中心には、集合体結合器の操作棒23
が集合体10を貫通しており、下部タイプレート7の下
端には、集合体結合器挿入部24を設け、操作棒23と
結合している。一方、制御棒案内管12の上端には燃料
支持金具32が結合しており、燃料支持金具32には、
集合体結合器受容部(ソケット)21が設けである。集
合体結合、器は、結合器上端22で、操作棒23を下に
押すことで、集合体10と燃料支持金具32を結合する
。操作棒23に加えた力を除くと、操作棒23は、ばね
24の作用により上に戻り、集合体10と燃料支持金具
32の結合を解除する。At the center of the fuel assembly 10 is an operation rod 23 of the assembly coupler.
passes through the assembly 10 , and an assembly coupler insertion portion 24 is provided at the lower end of the lower tie plate 7 and is coupled to the operating rod 23 . On the other hand, a fuel support fitting 32 is connected to the upper end of the control rod guide tube 12, and the fuel support fitting 32 includes:
An aggregate coupler receptacle (socket) 21 is provided. The assembly coupling device couples the assembly 10 and the fuel support fitting 32 by pushing down the operating rod 23 at the coupling upper end 22. When the force applied to the operating rod 23 is removed, the operating rod 23 returns upward due to the action of the spring 24, releasing the connection between the assembly 10 and the fuel support fitting 32.
第3図には、結合器挿入部20.受容部21の一実施例
を示す。第3図(a)は結合前の図で、挿入部20は、
プラグ25aとスパッド26から構成する。燃料集合体
を燃料支持金具の上に置くと、スパッド26が、ソケッ
ト21にはめこまれる。そこで第3図(b)のようにプ
ラグ25bを下に押しこむと、スパッド26が拡がり、
ソケット21と結合する。FIG. 3 shows a coupler insertion section 20. An example of the receiving part 21 is shown. FIG. 3(a) is a diagram before coupling, and the insertion portion 20 is
It consists of a plug 25a and a spud 26. When the fuel assembly is placed on the fuel support fitting, the spud 26 fits into the socket 21. Then, when the plug 25b is pushed down as shown in FIG. 3(b), the spud 26 expands.
It is coupled with the socket 21.
第4図には、結合器構造の他の実施例を示す。FIG. 4 shows another embodiment of the coupler structure.
第4図(a)は結合前の図で、結合器挿入部20はプラ
グ25bとラッチ27から構成する。ラッチ27をソケ
ット21に挿入後、第4図(b)のようにプラグ25b
を押し下げると、ラッチ27がソケット21bにかみあ
い結合する。分離する時には、プラグ25bを引きあげ
ればラッチ27がソケット21bからはずれる。FIG. 4(a) is a diagram before coupling, and the coupler insertion portion 20 is composed of a plug 25b and a latch 27. After inserting the latch 27 into the socket 21, plug 25b is inserted as shown in Fig. 4(b).
When pressed down, the latch 27 engages and connects to the socket 21b. When separating, the latch 27 is removed from the socket 21b by pulling up the plug 25b.
第5図には、結合器構造の他の実施例を示す。FIG. 5 shows another embodiment of the coupler structure.
第5図(a)は結合前の図で、ロッド28の溝にボール
29がはいった構造になっている。結合するには、ソケ
ット21cに挿入部20を差しこみ、ロッド28を押し
下げる。するとボール29が、ロッド28の溝から、ソ
ケット21cの溝に移動し、第5図(b)のように結合
する。この場合もロッド28を引きあげればよい。FIG. 5(a) is a diagram before connection, in which the ball 29 is inserted into the groove of the rod 28. To connect, insert the insertion part 20 into the socket 21c and push down the rod 28. Then, the ball 29 moves from the groove of the rod 28 to the groove of the socket 21c and is connected as shown in FIG. 5(b). In this case as well, the rod 28 can be pulled up.
結合器操作棒23を押し下げる操作は、第1図に示すよ
うに燃料集合体10の上部に設置した上部炉心板13に
設けた集合体固定操作ビン14で、集合体結合器操作部
22を押すことによって達成される。燃料交換的には、
この上部炉心板13を一時的に取り除き、すべての燃料
集合体が移動可能とする。また、上部炉心板13は、燃
料集合体10の上部タイプレートlとは接触していない
ので、燃料集合体10の伸びによって応力を受けること
はない。To push down the coupler operating rod 23, as shown in FIG. This is achieved by In terms of fuel exchange,
This upper core plate 13 is temporarily removed to allow all fuel assemblies to be moved. Further, since the upper core plate 13 is not in contact with the upper tie plate l of the fuel assembly 10, it is not subjected to stress due to the elongation of the fuel assembly 10.
[発明の効果]
本発明によれば、燃料集合体を原子炉圧力容器内の下部
構造物に剛に結合することができるので、沸騰水型原子
炉でも、揚力の変動にともなう燃料集合体の上下振動を
防ぐことができ、構造材の強度や限界圧力を劣化させる
ことがない。[Effects of the Invention] According to the present invention, the fuel assembly can be rigidly connected to the lower structure in the reactor pressure vessel, so even in a boiling water reactor, the fuel assembly can be fixed evenly due to fluctuations in lift force. Vertical vibration can be prevented, and the strength and critical pressure of structural materials will not deteriorate.
第1図は本発明の一実施例の集合体の縦断面図、第2図
は本発明を適用した炉心構成を示す縦断面図、第3図な
いし第5図は本発明による集合体結合部の詳細な構造を
示す断面図である。
l・・・上部タイブレート、2・・・燃料棒端栓挿入板
、3・・・制御棒案内シンプル管、4・・・燃料棒、5
・・・チャンネルボックス、6・・・スペーサ、7・・
・下部タイプレート、8・・・クラスタ型制御棒、9・
・・制御棒駆動機構、10・・・燃料集合体、11・・
・インターナルポンプ、12・・・制御棒案内管、13
・・−上部炉心板、14・・・集合体固定操作ビン、1
5・・・上部シュラウド、16・・・炉心シュラウド、
17・・・蒸気乾燥器、18・・・汽水分離器、19・
・・原子炉圧力容器、20・・・集合体結合器挿入部、
21・・・集合体結合器受容部(ソケット)、22・・
・集合体結合器操作部、23・・・集合体結合部操作棒
、24・・・バネ、25・・・プラグ、26・・・スパ
ッド、27・・・ラッチ、28・・・ロッド、29・・
・ボール、30・・・主蒸気管、31・・・給水管。
第3図
26・・・ ス/X′ット
(cL) (b)草 d
25b−−−−y°″5Z°゛
27−−− ラッテ
21 b 21 b
第 5
20C・・濃公体。
21C・・ ヶ
2B ・・・ 口・アト°。
29 ・、−才′′−ル
ノ2θC
IC
(ζ)
図
受客卸
(b)FIG. 1 is a longitudinal sectional view of an assembly according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing a core configuration to which the present invention is applied, and FIGS. 3 to 5 are assembly joints according to the present invention. FIG. 3 is a cross-sectional view showing the detailed structure of l... Upper tie plate, 2... Fuel rod end plug insertion plate, 3... Control rod guide simple tube, 4... Fuel rod, 5
...Channel box, 6...Spacer, 7...
・Lower tie plate, 8...Cluster type control rod, 9・
...Control rod drive mechanism, 10...Fuel assembly, 11...
・Internal pump, 12...Control rod guide tube, 13
...-Upper core plate, 14...Aggregation fixed operation bin, 1
5... Upper shroud, 16... Core shroud,
17...Steam dryer, 18...Brackish water separator, 19.
... Reactor pressure vessel, 20 ... Assembly coupler insertion part,
21... Aggregate coupler receiving part (socket), 22...
- Aggregate coupler operating section, 23... Aggregate coupling section operating rod, 24... Spring, 25... Plug, 26... Spud, 27... Latch, 28... Rod, 29・・・
- Ball, 30... Main steam pipe, 31... Water supply pipe. Fig. 3 26... S/X't (cL) (b) Grass d 25b---y°''5Z°゛27--- Latte 21 b 21 b 5th 20C...Kokotai. 21C... ga2B...mouth/atoo. 29 ・, -Sai''-Luno 2θC IC (ζ) Figure Customer Wholesaler (b)
Claims (1)
料集合体を設置する原子炉において、燃料集合体下端を
燃料支持金具上端部に燃料集合体結合器を設け、燃料集
合体を貫通した燃料集合体結合器操作棒を、燃料合体の
上部から操作して上、下に移動させることにより、前記
燃料集合体と燃料支持金具との着脱を可能にしたことを
特徴とする原子炉。 2、請求項1において、前記燃料集合体の上方に設けた
上部炉心板により結合器、操作棒を上下させ、前記燃料
集合体と前記燃料支持金具の着脱操作をする構造とした
原子炉。 3、請求項1において、前記燃料集合体結合器として、
プラグとスパッドとソケット、または、プラグとラッチ
とソケット、あるいは、溝にボールをとりつけたロッド
とソケットを利用する原子炉。[Claims] 1. In a nuclear reactor in which a fuel assembly is installed on a fuel support fitting fixed in a reactor pressure vessel, a fuel assembly coupler is provided to connect the lower end of the fuel assembly to the upper end of the fuel support fitting. , by operating a fuel assembly coupler operating rod that penetrates the fuel assembly from the top of the fuel assembly and moving it up and down, the fuel assembly and the fuel support fitting can be attached and detached. Characteristic nuclear reactor. 2. The nuclear reactor according to claim 1, wherein the coupler and the operating rod are moved up and down by an upper core plate provided above the fuel assembly to attach and detach the fuel assembly and the fuel support fitting. 3. In claim 1, as the fuel assembly coupler,
A nuclear reactor that uses a plug and spud and socket, or a plug and latch and socket, or a rod and socket with a ball in a groove.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2329037A JPH04204087A (en) | 1990-11-30 | 1990-11-30 | Nuclear reactor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2329037A JPH04204087A (en) | 1990-11-30 | 1990-11-30 | Nuclear reactor |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH04204087A true JPH04204087A (en) | 1992-07-24 |
Family
ID=18216899
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2329037A Pending JPH04204087A (en) | 1990-11-30 | 1990-11-30 | Nuclear reactor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH04204087A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006313145A (en) * | 2005-05-02 | 2006-11-16 | Westinghouse Electric Co Llc | Restricted assembly in core and reactor core |
-
1990
- 1990-11-30 JP JP2329037A patent/JPH04204087A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006313145A (en) * | 2005-05-02 | 2006-11-16 | Westinghouse Electric Co Llc | Restricted assembly in core and reactor core |
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