JPH01124793A - Fuel assembly - Google Patents
Fuel assemblyInfo
- Publication number
- JPH01124793A JPH01124793A JP62282007A JP28200787A JPH01124793A JP H01124793 A JPH01124793 A JP H01124793A JP 62282007 A JP62282007 A JP 62282007A JP 28200787 A JP28200787 A JP 28200787A JP H01124793 A JPH01124793 A JP H01124793A
- Authority
- JP
- Japan
- Prior art keywords
- screw
- short
- fuel
- support plate
- fuel rod
- 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 title claims abstract description 100
- 125000006850 spacer group Chemical group 0.000 claims description 6
- 210000000078 claw Anatomy 0.000 claims description 5
- 238000005253 cladding Methods 0.000 abstract description 5
- 239000002826 coolant Substances 0.000 abstract description 4
- 239000012530 fluid Substances 0.000 abstract description 2
- 230000003449 preventive effect Effects 0.000 abstract 2
- 230000010355 oscillation Effects 0.000 abstract 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 230000000712 assembly Effects 0.000 description 4
- 238000000429 assembly Methods 0.000 description 4
- 239000008188 pellet Substances 0.000 description 3
- 230000002265 prevention Effects 0.000 description 3
- 238000009835 boiling Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects 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
- Fuel-Injection Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明は熱水力学特性を向上させるために燃料チャンネ
ルボックス内に長尺燃料棒とともに短尺燃料棒を組込ん
だ燃料集合体に関する。Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention provides a fuel assembly that incorporates short fuel rods together with long fuel rods in a fuel channel box to improve thermo-hydraulic properties. Regarding the body.
（従来の技術）
沸騰水型原子炉用燃料集合体は燃料チャンネルボックス
内に長尺燃料棒のみを組込んだものが一般的であったが
、最近では活発な核特性および熱水力学特性を改善させ
るために長尺燃料棒と短尺燃料棒を組込んだ炉心燃料の
設計が行われている。(Prior art) Fuel assemblies for boiling water reactors generally have only long fuel rods built into the fuel channel box, but recently, fuel assemblies for boiling water reactors have been designed to incorporate only long fuel rods into fuel channel boxes. To improve this, core fuel designs incorporating long and short fuel rods are being developed.
この短尺燃料棒を組込んだ燃料集合体は第５図に示した
ように形成されているが、基本的なｔ′ＦＩＩ造は従来
の一般的長尺燃料棒のみを組込んだ燃ｆ４集合体と同様
である。A fuel assembly incorporating these short fuel rods is formed as shown in Fig. 5, but the basic t'FII structure is a conventional fuel assembly incorporating only long fuel rods. It is similar to the body.
すなわち、第５図において符号１は燃料チャンネルボッ
クスで、このチャンネルボックス１内に長尺燃料棒２と
短尺燃料棒３の下端が下部支持板４に挿着されている。That is, in FIG. 5, reference numeral 1 denotes a fuel channel box, in which the lower ends of long fuel rods 2 and short fuel rods 3 are inserted into a lower support plate 4.
また長尺燃料棒２の上端は上部支持板５に挿着されてい
る。各々の燃料棒２゜３間はスペーサ６によって所定の
間隔が保持されるようになっている。Further, the upper end of the long fuel rod 2 is inserted into an upper support plate 5. A predetermined distance is maintained between the fuel rods 2.3 by spacers 6.
このように上部支持板５と下部支持板４との間に複数本
の長尺燃料棒２と短尺燃料棒３および図示してないが複
数本のウォータロッドを正方格子状に配列し、燃料ｎ２
．３の軸方向の複数個所に設けたスペーサ６によって燃
料棒２．３とウォータロッドの所定間隔を保持している
。また前記上部支持板うは長尺燃料棒２およびウォータ
ロッドの上端を固定して回転を防止し、下部支持板４は
長尺燃料ｎ２、短尺燃料棒３およびウォータロッドの下
端を固定し下方からの流動録動などによる回転を防止し
ている。さらに長尺燃料棒２およびウォータロッドと上
部支持板５との間にはスプリング７が介挿され、使用中
の燃料棒２およびウォータロッドの伸びを吸収している
。In this way, a plurality of long fuel rods 2, a plurality of short fuel rods 3, and a plurality of water rods (not shown) are arranged in a square grid between the upper support plate 5 and the lower support plate 4, and the fuel n2
．． A predetermined distance between the fuel rod 2.3 and the water rod is maintained by spacers 6 provided at a plurality of locations in the axial direction of the fuel rod 2.3. The upper support plate 4 fixes the upper ends of the long fuel rods 2 and the water rods to prevent rotation, and the lower support plate 4 fixes the lower ends of the long fuel rods 2, the short fuel rods 3, and the water rods from below. This prevents rotation due to fluid recording, etc. Furthermore, a spring 7 is interposed between the long fuel rod 2 and water rod and the upper support plate 5 to absorb the elongation of the fuel rod 2 and water rod during use.
（発明が解決しようとする問題点）
しかしながら、従来の短尺燃料棒を組込んだ燃料集合体
は次のような問題点があった。(Problems to be Solved by the Invention) However, conventional fuel assemblies incorporating short fuel rods have the following problems.
すなわち、短尺燃料棒３の上端は固定されてなく自由に
なっているため軸方向の上向きに浮き上り、短尺燃料棒
３の下端が下部支持板４からはずれる恐れがあった。ま
た、場合によっては短尺燃料棒３が回転してスペーサ６
と短尺燃料棒３の接点においてその面に傷が付いて短尺
燃料ｎ３の健全性を損う恐れがあった。That is, since the upper end of the short fuel rod 3 is not fixed and is free, it floats upward in the axial direction, and there is a risk that the lower end of the short fuel rod 3 may come off from the lower support plate 4. In addition, in some cases, the short fuel rods 3 rotate and the spacers 6
There was a risk that the surface of the short fuel rod 3 would be damaged at the contact point between the short fuel rod 3 and the integrity of the short fuel rod n3.
そのなめ、短尺燃料棒３の下端を下部支持板４にねじ込
んで結合する手段も考えられるが、ねじが使用中の原子
炉内の水力振動によって弛んでしまい、その結果短尺燃
料棒３が浮上り、回転してしまう危惧は避けられないな
どの問題点がある。Therefore, a method of connecting the lower ends of the short fuel rods 3 to the lower support plate 4 by screwing them is considered, but the screws loosen due to hydraulic vibrations in the reactor during use, and as a result, the short fuel rods 3 float up. , there are problems such as the unavoidable risk of rotation.
本発明はかかる問題点を解決するためになされたもので
、短尺燃料棒が回転したり、浮上ったりすることを防止
した信頼性の高い燃料集合体を提供することにある。The present invention has been made to solve these problems, and an object of the present invention is to provide a highly reliable fuel assembly that prevents short fuel rods from rotating or floating.
［発明の構成］
（問題点を解決するための手段）
本発明の燃料集合体は、燃料チャンネルボックス内に上
部支持板および下部支持板を介して上下両端部が固定さ
れた複数本の長尺燃料棒と、下部支持板に下端部が固定
された複数本の短尺燃料棒とがスペーサを介して正方格
子状に配列されて組込まれてなる燃ｆｌ＠合体において
、前記短尺燃料棒の下端部と下部支持板との間に相互に
係合して前記短尺燃料棒の回転を防止する回転防止機構
を設けるとともに前記短尺燃料棒を前記下部支持板に固
定する固定機構を設けたことを特徴とする。[Structure of the Invention] (Means for Solving the Problems) The fuel assembly of the present invention comprises a plurality of elongated rods whose upper and lower ends are fixed in a fuel channel box via an upper support plate and a lower support plate. In a fuel fl@ combination in which a fuel rod and a plurality of short fuel rods whose lower ends are fixed to a lower support plate are arranged and assembled in a square grid via spacers, the lower ends of the short fuel rods are assembled. and a lower support plate are provided with a rotation prevention mechanism that engages with each other to prevent rotation of the short fuel rod, and a fixing mechanism that fixes the short fuel rod to the lower support plate. do.
（作用）
本発明によれば、回転防止機構と固定機構との組合せに
よって冷却材の流動振動によって短尺燃料棒が回転しよ
うとしても回転力が阻止されて短尺燃料棒の浮上りを防
止し、もって燃料集合体の信頼性を向上させる。(Function) According to the present invention, even if the short fuel rods try to rotate due to the flow vibration of the coolant, the rotational force is blocked by the combination of the rotation prevention mechanism and the fixing mechanism, thereby preventing the short fuel rods from floating. Improve reliability of fuel assemblies.
（実施例）
第１図から第４区を参照しながら本発明の一実施例を説
明する。(Example) An example of the present invention will be described with reference to sections 4 from FIG.
第１図は本発明に係る燃料集合体の短尺燃料棒を一部断
面で示した斜視図で、第２図は第１図における短尺燃料
棒の下部を拡大して示す部分斜視図である。FIG. 1 is a partially cross-sectional perspective view of a short fuel rod of a fuel assembly according to the present invention, and FIG. 2 is a partially enlarged perspective view of the lower part of the short fuel rod in FIG. 1.
すなわち、短尺燃料棒８は被覆ｇ−９内に燃料ベレット
１０が積層して装填され、燃料ペレット１０の上端にス
プリング１１が配置され、被覆管９の上端は上部は上部
端栓１２で密閉され、また被覆管９の下端部は下部端栓
１３で密封された構造になっている。下部端栓１３は被
覆管９内に挿入される柱部１４と、短尺燃料棒８の回転
を防止する回転防止機構として上部ねじ１５と、下部支
持板４に固定するための固定機構としての下部ねじ１６
とが設けられている。上部ねじ１５と下部ねじ１６とは
逆ねじの関係にねじが切られており、また上部ねじ１５
の直径は下部ねじ１６の直径よりも大きい。上部ねじ１
５にはナツト１７がねじ込まれ、下部ねじ１６にはワッ
シャ１８が挿入される。ワッシャ１８には３枚の羽根１
９と下方に延びる爪２０とが設けられている。下部ねじ
１６は第３図に示した下部支持板４のめねじ２１にねじ
込まれ、爪２０は下部支持板４のめねじ２１の近傍に設
けたキー渭２２に挿入され、羽根１９はナツトの側面を
抱持してゆるみ止めの作用を行なう。That is, the short fuel rod 8 is loaded with fuel pellets 10 stacked in a cladding g-9, a spring 11 is arranged at the upper end of the fuel pellet 10, and the upper end of the cladding tube 9 is sealed with an upper end plug 12. The lower end of the cladding tube 9 is sealed with a lower end plug 13. The lower end plug 13 includes a column portion 14 inserted into the cladding tube 9, an upper screw 15 as a rotation prevention mechanism for preventing rotation of the short fuel rod 8, and a lower portion as a fixing mechanism for fixing it to the lower support plate 4. screw 16
and is provided. The upper screw 15 and the lower screw 16 are threaded in a reverse thread relationship, and the upper screw 15
is larger than the diameter of the lower screw 16. Upper screw 1
A nut 17 is screwed into the lower screw 16, and a washer 18 is inserted into the lower screw 16. Washer 18 has three blades 1
9 and a claw 20 extending downward. The lower screw 16 is screwed into the female thread 21 of the lower support plate 4 shown in FIG. Holds the sides to prevent loosening.
次に上記短尺燃料棒８を下部支持板４に組立てる方法に
ついて第２図から第４図を参照しながら説明する。Next, a method for assembling the short fuel rods 8 to the lower support plate 4 will be explained with reference to FIGS. 2 to 4.
まず、上部ねじ１５にナツト１７を取り付けておく、上
述したように上部ねじ１５の外径は下部ねじ１６の山径
つまり外径よりも大きいので、下部ねじ１６を通過して
上部ねじ１５に挿入つまりねじ込むことができる。次に
ワッシャ１８を爪２０と下部支持板４のキー渭２２に係
合させるようにして下部支持板４の上面に配置する。つ
づいて、上記短尺燃料棒８の下部ねじ１６をワッシャ１
８の孔を貫通させて下部支持板４のめねじ２１にねじ込
んで結合させる。そして、ナツト１７を絞めつけ、最後
に第４図に示したようにワッシャ１８のゆるみ止め羽根
１９をナツト１７の中心方向に折り曲げてナツト１７の
ゆるみ止めを行なう。First, attach the nut 17 to the upper screw 15. As mentioned above, the outer diameter of the upper screw 15 is larger than the thread diameter, that is, the outer diameter of the lower screw 16, so it is inserted into the upper screw 15 by passing through the lower screw 16. In other words, it can be screwed in. Next, the washer 18 is placed on the upper surface of the lower support plate 4 so as to engage the claw 20 and the key lever 22 of the lower support plate 4. Next, tighten the lower screw 16 of the short fuel rod 8 with the washer 1.
8 and screwed into the female thread 21 of the lower support plate 4 to connect them. Then, the nut 17 is tightened, and finally the locking blade 19 of the washer 18 is bent toward the center of the nut 17 to prevent the nut 17 from loosening, as shown in FIG.
このように構成することによって、燃料チャンネルボッ
クス１内を流れる冷却材の流動振動により短尺燃料棒８
が回転しようとしても、上部ねじ１５と下部ねじとが逆
ねじの関係になっているため短尺燃料棒８が回転するこ
とがない。With this configuration, the short fuel rods 8 are caused by the flow vibration of the coolant flowing inside the fuel channel box 1.
Even if the short fuel rod 8 tries to rotate, the short fuel rod 8 will not rotate because the upper screw 15 and the lower screw have a reverse screw relationship.
また、ナツト１７はワッシャ１８の羽根１９によってゆ
るみ止めがなされているのでゆるむことはない。Further, the nut 17 is prevented from loosening because it is prevented from loosening by the blades 19 of the washer 18.
［発明の効果］
本発明によれば短尺燃料棒が下部支持板に確実に固定さ
れているので、冷却材の流動振動によって燃料チャンネ
ルボックス内で回転したり、また浮上ったりすることを
防止できる。[Effects of the Invention] According to the present invention, since the short fuel rods are securely fixed to the lower support plate, it is possible to prevent them from rotating or floating within the fuel channel box due to flow vibration of the coolant. .
よって、燃料集合体自体の信頼性を向上させることがで
きる。Therefore, the reliability of the fuel assembly itself can be improved.
第１図から第４図までは本発明に係る燃料集合体の一実
施例を説明するための図で、第１図は燃料棒の斜視図、
第２図は第１図の下端部を分解して示す斜視図、第３図
は下部支持板の部分拡大斜視図、第４図は下部支持板に
燃料棒を組立てた状態を示す立面図、第５図は従来の燃
料集合体を示す縦断面図である。
１・・・・・・・・・・・・燃料チャンネルボックス２
・・・・・・・・・・・・長尺燃料棒３．８・・・・・
・短尺燃料棒
４・・・・・・・・・・・・下部支持板５・・・・・・
・・・・・・上部支持板６・・・・・・・・・・・・ス
ペーサ
７・・・・・・・・・・・・スプリング９・・・・・・
・・・・・・被覆管
１０・・・・・・・・・燃料ペレット
１１・・・・・・・・・スプリング
１２・・・・・・・・・上部端栓
１３・・・・・・・・・下部端栓
１４・・・・・・・・・幹部
１５・・・・・・・・・上部ねじ
１６・・・・・・・・・下部ねじ
１７・・・・・・・・・ナツト
１８・・・・・・・・・ワッシャ
１９・・・・・・・・・羽根
２０・・・・・・・・・爪
２１・・・・・・・・・めねじ
２２・・・・・・・・・キー渭
代理人 弁理士 則 近 憲 佑
同 第子丸 健
第３２
第４０
−５丁1 to 4 are diagrams for explaining one embodiment of a fuel assembly according to the present invention, and FIG. 1 is a perspective view of a fuel rod;
Fig. 2 is an exploded perspective view of the lower end of Fig. 1, Fig. 3 is a partially enlarged perspective view of the lower support plate, and Fig. 4 is an elevational view showing the state in which fuel rods are assembled to the lower support plate. , FIG. 5 is a longitudinal sectional view showing a conventional fuel assembly. 1・・・・・・・・・・・・Fuel channel box 2
・・・・・・・・・・・・Long fuel rod 3.8・・・・・・
・Short fuel rod 4・・・・・・・・・Lower support plate 5・・・・・・
・・・・・・Upper support plate 6・・・・・・・・・Spacer 7・・・・・・・・・Spring 9・・・・・・
......Claying tube 10...Fuel pellets 11... Spring 12... Upper end plug 13... ...Lower end plug 14... Trunk 15... Upper screw 16... Lower screw 17... ...Nut 18...Washer 19...Blade 20...Claw 21...Female thread 22.・・・・・・・・・Key Wei's agent Patent attorney Nori Chika Ken Yudo Daishimaru Ken No. 32 No. 40-5
Claims (3)
部支持板を介して上下両端部が固定された複数本の長尺
燃料棒と、下部支持板に下端部が固定された複数本の短
尺燃料棒とがスペーサを介して正方格子状に配列されて
組込まれてなる燃料集合体において、前記短尺燃料棒の
下端部と下部支持板との間に相互に係合して前記短尺燃
料棒の回転を防止する回転防止機構を設けるとともに前
記短尺燃料棒を前記下部支持板に固定する固定機構を設
けたことを特徴とする燃料集合体。(1) A plurality of long fuel rods whose upper and lower ends are fixed inside the fuel channel box via an upper support plate and a lower support plate, and a plurality of short fuel rods whose lower ends are fixed to a lower support plate. and a fuel assembly in which the short fuel rods are arranged and assembled in a square lattice shape via spacers, the lower ends of the short fuel rods and the lower support plate are mutually engaged with each other to control the rotation of the short fuel rods. A fuel assembly characterized in that it is provided with an anti-rotation mechanism for preventing rotation and a fixing mechanism for fixing the short fuel rod to the lower support plate.
ねじと下部ねじとが逆ねじの関係に設けられかつ上部ね
じにナットがねじ込まれ、このナットを羽根および爪が
設けられたワッシャの前記羽根を折り曲げて抱持したも
のからなることを特徴とする特許請求の範囲第１項記載
の燃料集合体。(2) The anti-rotation mechanism has an upper screw and a lower screw installed in the lower end plug of the short fuel rod in a reverse thread relationship, a nut screwed into the upper screw, and a washer provided with a blade and a claw. 2. A fuel assembly according to claim 1, characterized in that said blades are bent and held together.
部ねじと前記ワッシャの爪からなることを特徴とする特
許請求の範囲第１項記載の燃料集合体。(3) The fuel assembly according to claim 1, wherein the fixing mechanism comprises a lower screw provided on the lower end plug of the short fuel rod and a claw of the washer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62282007A JPH01124793A (en) | 1987-11-10 | 1987-11-10 | Fuel assembly |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62282007A JPH01124793A (en) | 1987-11-10 | 1987-11-10 | Fuel assembly |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01124793A true JPH01124793A (en) | 1989-05-17 |
Family
ID=17646924
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62282007A Pending JPH01124793A (en) | 1987-11-10 | 1987-11-10 | Fuel assembly |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01124793A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0393799U (en) * | 1990-01-12 | 1991-09-25 | ||
| JP2008523363A (en) * | 2004-12-09 | 2008-07-03 | アレヴァ エンペー ゲゼルシャフト ミット ベシュレンクテル ハフツング | Boiling water reactor fuel assemblies |
-
1987
- 1987-11-10 JP JP62282007A patent/JPH01124793A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0393799U (en) * | 1990-01-12 | 1991-09-25 | ||
| JP2008523363A (en) * | 2004-12-09 | 2008-07-03 | アレヴァ エンペー ゲゼルシャフト ミット ベシュレンクテル ハフツング | Boiling water reactor fuel assemblies |
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