JPH05126978A - Upper grid plate for nuclear reactor - Google Patents
Upper grid plate for nuclear reactorInfo
- Publication number
- JPH05126978A JPH05126978A JP3289796A JP28979691A JPH05126978A JP H05126978 A JPH05126978 A JP H05126978A JP 3289796 A JP3289796 A JP 3289796A JP 28979691 A JP28979691 A JP 28979691A JP H05126978 A JPH05126978 A JP H05126978A
- Authority
- JP
- Japan
- Prior art keywords
- plate
- grid
- nuclear reactor
- fuel assembly
- lattice plate
- 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
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
【0001】[0001]
【産業上の利用分野】本発明は沸騰水型原子炉に用いら
れる、炉心シュラウド上部に組み込まれて燃料集合体の
上端を保持する炉内構造物としての上部格子板に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an upper lattice plate as an internal structure for a boiling water reactor, which is incorporated in an upper portion of a core shroud and holds an upper end of a fuel assembly.
【0002】[0002]
【従来の技術】沸騰水型原子炉では炉心荷重の支持や制
御棒の挿入空間、燃料集合体や制御棒の交換性を考慮し
て炉内構造物が設置されている。原子炉圧力容器内に
は、多数体の燃料集合体と制御棒の集団で炉心を構成し
ている。炉心内の燃料集合体は下部においては炉心支持
板により水平方向に位置決めされており、燃料集合体の
荷重は炉心支持板の穴を介して制御棒案内管によって支
持されている。2. Description of the Related Art In a boiling water reactor, reactor internals are installed in consideration of support of core load, insertion space of control rods, exchangeability of fuel assemblies and control rods. In the reactor pressure vessel, a core is composed of a large number of fuel assemblies and a group of control rods. The fuel assembly in the core is positioned horizontally by the core support plate in the lower part, and the load of the fuel assembly is supported by the control rod guide tube through the hole of the core support plate.
【0003】また、炉心の上部において燃料集合体の上
端は図9に示した上部格子板1によって水平方向に支持
されている。上部格子板1は図9に示すように横梁2と
縦梁3とを格子状に組み合わせたもので、その組み合わ
せ方法は図10(a)に示すように厚さ13.5mm程度、幅 1
50mm程度の鋼性の横梁2と縦梁3とを障子の桟のように
両者に切り欠き部4を設け、図10(b)に示したように
両者の切り欠き部4を噛み合わせて押圧し格子状に形成
している。そして、図9に示したように外周部を円形に
形成して上部格子板1を構成し、上部格子板1は炉心シ
ュラウドの上部に組み込まれて炉心上部に設置される。The upper end of the fuel assembly in the upper part of the core is horizontally supported by the upper lattice plate 1 shown in FIG. As shown in FIG. 9, the upper grid plate 1 is a combination of horizontal beams 2 and vertical beams 3 in a grid pattern. The combination method is as shown in FIG.
A steel cross beam 2 and a vertical beam 3 of about 50 mm are provided with notches 4 on both sides like shovels for shoji screens, and as shown in FIG. 10 (b), the notches 4 are engaged and pressed. It is formed in a grid pattern. Then, as shown in FIG. 9, the outer peripheral portion is formed into a circular shape to form the upper lattice plate 1, and the upper lattice plate 1 is incorporated in the upper portion of the core shroud and installed on the upper portion of the core.
【0004】上部格子板1の枡目つまり、開口部の面積
は図11に示したように燃料集合体5が4体ずつ挿入でき
る大きさとなっている。このため、上部格子板は4体の
燃料集合体5からの水平方向荷重wHに耐えられるよう
に、上部格子板1の厚さh及び幅aは次式 (1)を満足す
るように設計され、前述した数値に決められている。 wH・1/(a・h2 )<C …(1) ここで、 wH:上部格子板の梁一個当りに加わる水平方向荷重 l:上部格子板の梁の開口部の一辺の長さ a:上部格子板の梁の幅(高さ方向の梁の厚さ) h:上部格子板の梁の厚さ(水平方向の梁の厚さ) C:設計条件 である。As shown in FIG. 11, the area of the mesh, that is, the opening of the upper lattice plate 1 is such that four fuel assemblies 5 can be inserted therein. Therefore, the upper lattice plate is designed so that the thickness h and the width a of the upper lattice plate 1 satisfy the following equation (1) so that the upper lattice plate can withstand the horizontal load wH from the four fuel assemblies 5. , It is decided by the above-mentioned numerical value. wH · 1 / (a · h 2 ) <C (1) where wH: Horizontal load applied to each beam of the upper lattice plate l: Length of one side of the opening of the beam of the upper lattice plate a: Beam width of upper lattice plate (thickness of beam in height direction) h: Thickness of beam of upper lattice plate (thickness of beam in horizontal direction) C: Design condition.
【0005】前述したように燃料集合体5は上部格子板
1によって水平方向に支持され、横梁2と縦梁3による
開口部には4体の燃料集合体5が挿入される。図12は上
部格子板1の開口部内に挿入された燃料集合体5と制御
棒7との相対位置関係で示すもので、図12に示したよう
に燃料集合体5間の間隔6は制御棒7が挿入できるよう
に制御棒7の厚さに対して適切な空間が確保されてい
る。As described above, the fuel assemblies 5 are horizontally supported by the upper lattice plate 1, and four fuel assemblies 5 are inserted into the openings formed by the horizontal beams 2 and the vertical beams 3. FIG. 12 shows the relative positional relationship between the fuel assemblies 5 inserted into the openings of the upper lattice plate 1 and the control rods 7. As shown in FIG. 12, the spacing 6 between the fuel assemblies 5 is the control rods. An appropriate space is ensured for the thickness of the control rod 7 so that 7 can be inserted.
【0006】横梁2の厚さと縦梁3を挟んだ燃料集合体
5,5同士の間隙(ナローギャップ)8は同じになって
いる。また、上部格子板1のひとつの開口部に位置する
燃料集合体5,5同士の間隙(ワイドギャップ)9は図
11に示したように燃料集合体5のチャンネルボックス上
部の外面に設置されるチャンネルパッド10及びチャンネ
ルファスナ11により確保されている。The thickness of the horizontal beam 2 and the gap (narrow gap) 8 between the fuel assemblies 5, 5 sandwiching the vertical beam 3 are the same. Further, the gap (wide gap) 9 between the fuel assemblies 5 and 5 located in one opening of the upper lattice plate 1 is shown in FIG.
As shown in FIG. 11, it is secured by the channel pad 10 and the channel fastener 11 installed on the outer surface of the upper part of the channel box of the fuel assembly 5.
【0007】制御棒7および大型制御棒のウイング7a
は上部格子板1の開口部に位置する4体の燃料集合体
5,5の間のワイドギャップ9に挿入、引き抜きされ
る。制御棒7は中性子吸収体B4C粉末をステンレス製
のポイズンチューブに充填し、上下を封止したものを配
列してステンレス板をU字型に曲げて部分的に冷却水導
入用の穴を開けたシース内部に配列して翼を構成し、こ
れら四つの翼を中央のタイロッドに結合して十字型の制
御棒が構成されている。なお、図12中符号7aは大型制
御棒のウイングを示している。Control rod 7 and large control rod wing 7a
Is inserted into and withdrawn from the wide gap 9 between the four fuel assemblies 5 and 5 located at the opening of the upper lattice plate 1. For the control rod 7, a neutron absorber B4C powder was filled in a poison tube made of stainless steel, and those sealed at the top and bottom were arranged and the stainless steel plate was bent into a U shape to partially form a hole for introducing cooling water. The wing is arranged inside the sheath to form a wing, and these four wings are connected to a central tie rod to form a cross-shaped control rod. Note that reference numeral 7a in FIG. 12 indicates a wing of a large control rod.
【0008】制御棒7の使用時は制御棒下部のカップリ
ング装置と制御棒駆動機構が接続され、原子炉圧力容器
の下部から上下に操作される。制御棒交換時には下部の
カップリングを解除用ハンドルにより解除した後、上部
のハンドルを治具によりつかんで炉心上部に引き上げて
交換する。制御棒7は使用することによってその中性子
吸収能力が減耗するため、一定の使用期間毎に交換する
必要があり、定期検査の燃料交換作業と同時に制御棒交
換も行われるのが普通である。When the control rod 7 is used, the coupling device at the bottom of the control rod and the control rod drive mechanism are connected, and the control rod 7 is operated vertically from the bottom of the reactor pressure vessel. When replacing the control rod, the lower coupling is released with the release handle, then the upper handle is grasped by a jig and pulled up to the upper part of the core for replacement. Since the neutron absorption capacity of the control rods 7 is reduced by use, it is necessary to replace the control rods at regular intervals of use, and the control rods are usually replaced at the same time as the fuel exchange work of the periodic inspection.
【0009】[0009]
【発明が解決しようとする課題】135万kWe 級の沸騰水
型原子炉の炉心は燃料集合体5の数が 872体にも上り、
燃料集合体5の交換時の作業工数が従来の 110万kWe 級
のものよりも増加する。今後の大容量化による燃料交換
作業の工数増加を抑制するために、燃料集合体の外形を
大きくすることが考えられる。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The core of a boiling water reactor of 1.35 million kWe has 872 fuel assemblies 5,
The work man-hours for replacing the fuel assembly 5 are increased compared to the conventional 1.1 million kWe class. In order to suppress an increase in the number of man-hours for refueling work due to future increase in capacity, it is conceivable to enlarge the outer shape of the fuel assembly.
【0010】しかしながら、燃料集合体5の外形を大き
くすると燃料集合体5一体当たりの重量が重くなる。例
えば、燃料集合体5の重量を従来燃料のM倍にすると設
計で考慮すべき水平方向重量wHもM倍になる。また、燃
料集合体5の横断面の一辺の長さをL倍にすると上部格
子板1の横梁2と縦梁3に加わるモーメントはM×L倍
になる。However, when the outer shape of the fuel assembly 5 is increased, the weight per unit of the fuel assembly 5 becomes heavy. For example, if the weight of the fuel assembly 5 is M times that of the conventional fuel, the horizontal weight wH to be considered in the design is also M times. When the length of one side of the cross section of the fuel assembly 5 is L times, the moment applied to the horizontal beams 2 and the vertical beams 3 of the upper lattice plate 1 is M × L times.
【0011】従来の上部格子板の設計基礎で、このモー
メントに耐えるようにするには式 (1)から明らかなよう
に上部格子板1の横梁2と縦梁3の厚さhをM×Lにす
るか、または上部格子板1の横梁2と縦梁3の幅aをM
×Lにする必要がある。例えば具体的にMが4、Lが2
となる場合について考えると上部格子板1の横梁2と縦
梁3の厚さhを従来の約 2.8倍の38mm以上の厚さが必要
である。In order to withstand this moment in the conventional design basis of the upper lattice plate, the thickness h of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1 is M × L as is clear from the equation (1). Or the width a of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1 is set to M
It is necessary to make xL. For example, M is 4 and L is 2
When considering the case, the thickness h of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1 needs to be 38 mm or more, which is about 2.8 times the thickness h of the conventional one.
【0012】しかしながら、上部格子板1の横梁2と縦
梁3の厚さhは燃料集合体の間の間隙(ナローギャッ
プ)の幅で制限されている。また、ナローギャップの幅
及びワイドギャップの幅は水対燃料体積比の関係を核的
に最適化するように設計されており、従来の設計では上
部格子板1の横梁2と縦梁3の厚さhを従来の約 2.8倍
の厚さにすることはナローギャップの幅より大きくなる
ことを意味し、採用することは出来ない。However, the thickness h of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1 is limited by the width of the gap (narrow gap) between the fuel assemblies. Further, the width of the narrow gap and the width of the wide gap are designed to nuclearly optimize the relationship of the water-fuel volume ratio, and in the conventional design, the thickness of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1 is set. Making the thickness h about 2.8 times thicker than the conventional one means that it is larger than the width of the narrow gap and cannot be adopted.
【0013】次に上部格子板1の横梁2と縦梁3厚さh
をナローギャップ幅の設定上許容できる約16mmに増や
し、上部格子板1の横梁2と縦梁3の幅aを増加させて
対応することも考えられる。しかしながら、その厚さは
従来の約6倍の約 880mm必要であるが、このような極厚
の上部格子板を一枚の極厚板材から削りだし加工で制作
することは技術的に難しい。また、図10に示したように
横梁2と縦梁3の板材を組み合わせて、上部格子板を製
作した場合にはさらに倍の1760mm必要となる。Next, the thickness h of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1
May be increased to about 16 mm, which is allowable in setting the narrow gap width, and the width a of the horizontal beam 2 and the vertical beam 3 of the upper lattice plate 1 may be increased to cope with this. However, the thickness is required to be about 880 mm, which is about 6 times as large as the conventional thickness, but it is technically difficult to machine such an extremely thick upper lattice plate by machining from one extremely thick plate material. Further, as shown in FIG. 10, when the plate members of the horizontal beam 2 and the vertical beam 3 are combined to manufacture the upper lattice plate, the doubled amount is 1760 mm.
【0014】上部格子板の下縁の位置は炉心有効長で決
まるため、上部格子板が従来よりも厚くなる分は、燃料
集合体の軸方向全長を伸ばし、上方に上部格子板上縁を
伸ばすことになる。後者のような組み板で製作する場合
は、燃料集合体の長さを約1600mm長くする必要が生じ
る。このように従来の技術では燃料集合体の圧損増加、
燃料集合体の形成加工費の増加を招き不利になる課題が
ある。Since the position of the lower edge of the upper lattice plate is determined by the effective core length, the axial lattice length of the fuel assembly is extended and the upper edge of the upper lattice plate is extended upward as much as the thickness of the upper lattice plate becomes thicker than before. It will be. In the case of manufacturing with the latter type of assembled plate, it is necessary to lengthen the fuel assembly by about 1600 mm. Thus, in the conventional technology, the pressure loss of the fuel assembly increases,
There is a problem that the cost of forming and processing the fuel assembly increases, which is disadvantageous.
【0015】本発明は上記課題を解決するためになされ
たもので、制御棒の交換作業が容易で、かつ格子板の板
厚を薄くして経済性を高めた上部格子板を提供しようと
いうものである。The present invention has been made in order to solve the above problems, and an object of the present invention is to provide an upper grid plate in which the control rods can be easily replaced and the grid plate is made thin to improve the economical efficiency. Is.
【0016】[0016]
【課題を解決するための手段】本発明は原子炉圧力容器
内の炉心シュラウド上部に組み込まれ複数の燃料集合体
の上端を保持する原子炉用上部格子板において、横梁と
縦梁とによって格子状に組まれた第1の格子体と第2の
格子体とを積層し一体化固定してなることを特徴とす
る。SUMMARY OF THE INVENTION The present invention relates to an upper grid plate for a reactor, which is incorporated in an upper part of a core shroud in a reactor pressure vessel and holds upper ends of a plurality of fuel assemblies, in a grid shape by a horizontal beam and a vertical beam. It is characterized in that the first lattice body and the second lattice body assembled in the above are laminated and integrally fixed.
【0017】[0017]
【作用】本発明によれば、従来技術の延長である 400mm
程度の極厚板からの一体削り出しの格子体を二枚組み合
わせ積層して一体化製作できるものであり、燃料集合体
4体分の荷重が有効な梁部分全体で受けられ、上部格子
板の高さ方向の厚さが組み合わせ方式の1/2にでき
る。According to the present invention, 400 mm which is an extension of the prior art
It is possible to integrally manufacture by laminating two pieces of integrally carved grids from an extremely thick plate, and the load of four fuel assemblies can be received by the entire effective beam part. The thickness in the height direction can be reduced to half that of the combination method.
【0018】また、上側に設ける格子体の開口部をずら
す事により燃料集合体一体一体が上側格子体で支持され
る構成にできる。これにより、燃料集合体同士の間隙を
保持するチャンネルファスナおよびチャンネルパッドが
不要となる。さらに、上部に設置する格子体1を複数個
の部分に分割できるようにすることによりその格子体の
取扱いが容易になる。Further, by shifting the opening of the lattice provided on the upper side, the fuel assembly can be integrally supported by the upper lattice. This eliminates the need for channel fasteners and channel pads that maintain a gap between the fuel assemblies. Furthermore, by making it possible to divide the lattice body 1 installed on the upper portion into a plurality of portions, the lattice body can be easily handled.
【0019】[0019]
【実施例】図1から図5を参照しながら本発明に係る原
子炉用上部格子板の第1の実施例を説明する。図1は本
発明に係る原子炉用上部格子板が 135万kWe 級の改良型
沸騰水型原子炉の原子炉圧力容器内に組み込まれた状態
を概略的に示している。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the upper lattice plate for a nuclear reactor according to the present invention will be described with reference to FIGS. FIG. 1 schematically shows a state in which an upper grid plate for a nuclear reactor according to the present invention is installed in a reactor pressure vessel of an improved boiling water reactor of 1.35 million kWe class.
【0020】図1において原子炉圧力容器12内のほぼ中
央から下方に炉心シュラウド13が設けられ、この炉心シ
ュラウド13によって炉心14が囲まれている。炉心14内の
燃料集合体(図示せず)は炉心支持板15と第1の格子体
16と第2の格子体17とが積層され一体化されてなる上部
格子板18によって保持される。この上部格子体18は炉心
シュラウド13の上部に組み込まれてボルトで固定され
る。In FIG. 1, a core shroud 13 is provided below the center of the reactor pressure vessel 12 and the core 14 is surrounded by the core shroud 13. The fuel assembly (not shown) in the core 14 is composed of the core support plate 15 and the first lattice body.
It is held by an upper lattice plate 18 in which 16 and the second lattice body 17 are laminated and integrated. The upper lattice body 18 is incorporated in the upper portion of the core shroud 13 and fixed by bolts.
【0021】第1の格子体16と第2の格子体17は図2に
示したように横梁19と縦梁20とを格子状に組み合わせて
両者16,17を積層し一体化固定したものであり、図3に
示す燃料集合体22の4体分を挿入する大きさの桝目つま
り開口部21を持っている。燃料集合体22の4体で囲まれ
た十字型の制御棒23が炉心の下部から挿入され上下に駆
動される。なお、図3中23aは制御棒23のブレードを固
定するセンターポストである。As shown in FIG. 2, the first grid member 16 and the second grid member 17 are formed by combining horizontal beams 19 and vertical beams 20 in a grid pattern and stacking them 16 and 17 in an integrated manner. There is a grid or opening 21 of a size into which four fuel assemblies 22 shown in FIG. 3 are inserted. A cross-shaped control rod 23 surrounded by four fuel assemblies 22 is inserted from the lower part of the core and driven up and down. Incidentally, reference numeral 23a in FIG. 3 is a center post for fixing the blade of the control rod 23.
【0022】制御棒23の駆動は図1に示したように炉心
14の下方にあって燃料集合体22の縦梁を受け、炉心14か
ら制御棒23を下方に引き抜いたとき制御棒23を収容する
制御棒案内管の内部を貫通する駆動軸を作動させる制御
棒駆動機構(制御棒駆動機構ハウジング24内に収容され
ている)によってなされる。なお、本実施例で用いる燃
料集合体22は図3及び図5に示した構造になっている。The control rod 23 is driven as shown in FIG.
A control rod that receives the vertical beam of the fuel assembly 22 below 14 and operates the drive shaft that penetrates the inside of the control rod guide tube that accommodates the control rod 23 when the control rod 23 is pulled downward from the core 14. This is performed by a drive mechanism (housed in a control rod drive mechanism housing 24). The fuel assembly 22 used in this embodiment has the structure shown in FIGS. 3 and 5.
【0023】この燃料集合体22,22aは一辺の長さが従
来の燃料集合体5の 1.2〜2倍の大型角筒状のチャンネ
ルボックス25(以後、大型チャンネルボックスと呼ぶ)
の対面する2面を結ぶ二枚一組の板状構造物26の二組に
よって、燃料棒28を4体の部分燃料集合体22aに区分
し、図5に示したように二枚の板状構造物29で挟まれる
断面を非沸騰水領域30とした大型燃料集合体を用いる。
なお、図中27はウォータロッドを、28は燃料棒を示して
いる。また、図3に示すように大型チャンネルボックス
25の対面する面を結ぶ板状構造物26の二組によって燃料
棒28を4体の部分燃料集合体に区分した大型燃料集合体
を用いても良い。The fuel assemblies 22 and 22a are large rectangular tube-shaped channel boxes 25 (hereinafter referred to as large-sized channel boxes) whose one side length is 1.2 to 2 times that of the conventional fuel assembly 5.
The fuel rods 28 are divided into four partial fuel assemblies 22a by two sets of two plate-like structures 26 that connect the two facing surfaces of the two plate-like structures 26 as shown in FIG. A large fuel assembly is used in which the cross section sandwiched by the structures 29 has a non-boiling water region 30.
In the figure, 27 is a water rod and 28 is a fuel rod. Also, as shown in FIG. 3, a large channel box
A large fuel assembly may be used in which the fuel rods 28 are divided into four partial fuel assemblies by two sets of plate-like structures 26 that connect the facing surfaces of 25.
【0024】ところで、図1に示したように炉心シュラ
ウド13と原子炉圧力容器12の内壁との間隙に形成される
ダウンカマー31の下部にはインターナショナル再循環ポ
ンプ32が複数(10〜12台)配置されている。By the way, as shown in FIG. 1, a plurality of international recirculation pumps 32 (10 to 12 units) are provided below the downcomer 31 formed in the gap between the core shroud 13 and the inner wall of the reactor pressure vessel 12. It is arranged.
【0025】復水器から流出した冷却水は給水加熱器で
加熱後、給水ポンプで原子炉圧力容器12の給水ノズル33
を経て給水スパージャ34から注入される。給水は炉心14
から流出した水,蒸気の二相流を気水分離器35及び蒸気
乾燥機3bによって蒸気と分離された高温水と混合され
てダウンカマー31を下降し、インターナショナルポンプ
32によって加圧され下部プレナム37へ入る。下部プレナ
ム37に入った水は炉心14に供給され燃料棒28の発熱によ
り沸騰する。炉心14で発生した蒸気は気水分離器35及び
蒸気乾燥器36により湿分が除かれ蒸気出口ノズル38から
タービンに向かう。The cooling water flowing out from the condenser is heated by the feed water heater, and then is fed by the feed water pump to the feed water nozzle 33 of the reactor pressure vessel 12.
And is injected from the water supply sparger 34. Water supply is core 14
The two-phase flow of water and steam flowing out of the mixer is mixed with the high temperature water separated from the steam by the steam separator 35 and the steam dryer 3b to descend the downcomer 31, and the international pump.
It is pressurized by 32 and enters the lower plenum 37. The water that has entered the lower plenum 37 is supplied to the core 14 and boils due to the heat generation of the fuel rods 28. The steam generated in the core 14 has its moisture removed by a steam separator 35 and a steam dryer 36, and travels from a steam outlet nozzle 38 to a turbine.
【0026】前述したように従来の原子炉では上部格子
板1を一個で燃料集合体5を支えている。そこで、図3
および図5に示したような一辺の長さが従来の燃料集合
体5の2倍で、かつ、重さが4倍の大型燃料集合体22を
装荷しようとした場合、本発明では上部格子板18の幅a
を従来の燃料集合体5を装荷する場合の従来の上部格子
板1の幅の2倍、つまり約 880mmにする必要がある。こ
のような幅を有する上部格子板を従来の技術で極厚板材
から削り出し加工で製作することは難しい。As described above, in the conventional nuclear reactor, one upper lattice plate 1 supports the fuel assembly 5. Therefore, FIG.
In addition, when an attempt is made to load a large-sized fuel assembly 22 having a side length twice as shown in FIG. 18 width a
Should be twice the width of the conventional upper grid plate 1 when the conventional fuel assembly 5 is loaded, that is, about 880 mm. It is difficult to manufacture an upper lattice plate having such a width by cutting a very thick plate material by a conventional technique.
【0027】これに対して本実施例によれば第1の格子
体16及び第2の格子体17の幅と厚さは従来の燃料集合体
5を装荷する場合と同じ幅約 400mmと厚さ約15mmで済
み、従来技術の延長上で製作することができる。On the other hand, according to the present embodiment, the width and thickness of the first grid body 16 and the second grid body 17 are the same as when the conventional fuel assembly 5 is loaded, that is, the width and the thickness are about 400 mm. It only takes about 15 mm and can be manufactured by extending the conventional technology.
【0028】上部格子板を変更して開口部の大きさを燃
料集合体一体分の大きさにすれば大型燃料集合体を装荷
する場合でも上部格子板の梁の幅及び厚さを変更する必
要はない。しかし、一定の中性子照射量を受けるごとに
行なわなければならない制御棒交換が出来なくなる不都
合を生じるが、これに対して本第1の実施例ではそれを
解消する。Even if a large fuel assembly is loaded, it is necessary to change the width and thickness of the beam of the upper lattice plate by changing the upper lattice plate so that the size of the opening is the size of the integral fuel assembly. There is no. However, the control rod exchange, which has to be performed every time a constant neutron irradiation dose is received, causes a disadvantage that this problem is solved in the first embodiment.
【0029】次に図6により本発明の第2の実施例を説
明する。図6(a)は第2の実施例の上部格子板39を示
し、図6(b)は第1の格子体40を、図6(c)は第2
の格子体41を示している。Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 6A shows the upper lattice plate 39 of the second embodiment, FIG. 6B shows the first lattice body 40, and FIG.
The grid 41 is shown.
【0030】この第2の実施例は第1の実施例と同じく
上部格子板39を第1の格子体40と第2の格子体41とを上
下に組み合わせて構成し、図6に示すように両者40,41
の桝目つまり開口部の周期を第1のと第2のとで燃料集
合体一体分だけずらせ両者を組み合わせると開口部の大
きさが燃料集合体一体分となるように設置する。第1の
格子体40と第2の格子体41とを積層し、桝目を揃え、第
1の格子体40に図2に示したガイドピン42を取り付け、
第2の格子体41にガイドピン42を挿入するたて孔部43を
設けることにより取り外し可能となる。例えば、第1の
格子体40は第2の格子体41にピン止めされ、クランプで
押さえる。大型燃料集合体を装荷する場合でも制御棒の
交換が可能である。このガイドピン42の効果により第1
の格子体40の着脱作業が容易にできる。In the second embodiment, as in the first embodiment, the upper lattice plate 39 is constructed by combining the first lattice body 40 and the second lattice body 41 vertically, and as shown in FIG. Both 40, 41
And the cycle of the opening is shifted by the amount corresponding to the integral of the fuel assembly between the first and the second, and the two are combined so that the size of the opening is equal to the integral of the fuel assembly. The first grid body 40 and the second grid body 41 are laminated, the grids are aligned, and the guide pins 42 shown in FIG. 2 are attached to the first grid body 40.
By providing the vertical hole portion 43 into which the guide pin 42 is inserted in the second lattice body 41, the second lattice body 41 can be removed. For example, the first grid body 40 is pinned to the second grid body 41 and held by a clamp. The control rod can be replaced even when a large fuel assembly is loaded. Due to the effect of this guide pin 42
It is possible to easily attach and detach the grid body 40.
【0031】また、上部格子板を第1および第2の実施
例と同じく第1の格子体と第2の格子体とで構成し、上
部の格子体を構成する梁の上下両縁にテーパー加工を施
してもよい。これにより第1の格子体の着脱作業を改善
し、燃料集合体の取扱いが容易になる。梁のテーパー加
工の効果により第1の格子体の着脱作業が容易にでき、
大型制御棒の出し入れが容易にできる。Further, the upper lattice plate is composed of the first lattice body and the second lattice body as in the first and second embodiments, and the upper and lower edges of the beams constituting the upper lattice body are tapered. May be given. This improves the attachment / detachment work of the first lattice body and facilitates the handling of the fuel assembly. Due to the effect of taper processing of the beam, it is possible to easily attach and detach the first grid body,
Large control rod can be easily taken in and out.
【0032】また、上部格子板を構成する梁の両縁にテ
ーパー加工を施す代わりに燃料集合体のチャンネルボッ
クス25の上端を図7に示すように上方に向けて面積が小
さくなるような絞り部25aを有する燃料集合体44と組み
合わせてもよい。このように燃料集合体を構成すれば第
1の格子体の着脱作業が容易にでき、大型制御棒の出し
入れが容易にできる。また、梁の厚さhにテーパーをつ
けることによって、実質的に肉厚を薄くして、強度が低
下する設計を避けることが出来る。Further, instead of tapering both edges of the beam forming the upper lattice plate, the upper end of the channel box 25 of the fuel assembly is directed upward as shown in FIG. It may be combined with the fuel assembly 44 having 25a. By constructing the fuel assembly in this way, the attachment and detachment work of the first lattice body can be facilitated and the large control rod can be easily taken in and out. Further, by tapering the thickness h of the beam, it is possible to substantially reduce the wall thickness and avoid a design in which the strength is reduced.
【0033】図8は本発明の第3の実施例を示した上部
格子板の平面図である。本実施例は第1の格子体45を90
度セクターで4分割できる様に4個の構成部品45a,45
b,45c,45dで作成したものである。第1の格子体45
をこのように構成することにより第1の格子体45の取扱
いが容易になる。FIG. 8 is a plan view of the upper grid plate showing the third embodiment of the present invention. In this embodiment, the first grid 45 is replaced by 90
4 component parts 45a, 45 so that it can be divided into 4 in each degree sector
b, 45c, 45d. First grid 45
With this configuration, the first grid body 45 can be easily handled.
【0034】本発明の実施態様を要約すればつぎのとお
りである。第1は上部格子板を第1の格子体と第2の格
子体の二枚によって構成し、この二枚を重ね合わせて一
体化固定すること。第2は上部格子板を第1の格子体と
第2の格子体の二枚によって構成し、前記第1の格子体
と第2の格子体はそれぞれ燃料集合体4体分の開口部を
持ち、両者の開口部の周期を燃料集合体一体分だけずら
せ両者を組み合わせると開口部の大きさが燃料集合体一
体分となるようにし、第1の格子体は定期検査時に取外
し、取付が可能であること。第3は上部格子板を第1の
格子体と第2の格子体の二枚によって構成し、前記第1
の格子体を複数個の部分に分割できるようにし、第1の
格子体は定期検査時に取外し、取付が可能にしたこと。The embodiments of the present invention are summarized as follows. First, the upper lattice plate is composed of two sheets, a first lattice body and a second lattice body, and these two sheets are superposed and integrally fixed. The second upper grid plate is composed of two sheets, a first grid body and a second grid body, and each of the first grid body and the second grid body has openings for four fuel assemblies. , The openings of both are shifted by the amount of the fuel assembly integrated so that the size of the opening becomes the size of the integrated fuel assembly, and the first grid can be removed and attached during the periodic inspection. To be. Thirdly, the upper lattice plate is composed of two sheets, a first lattice body and a second lattice body.
The grid body can be divided into a plurality of parts, and the first grid body can be removed and attached during the periodic inspection.
【0035】[0035]
【発明の効果】本発明によれば制御棒の交換時作業が容
易で、かつ格子板の板厚を薄くし必要な資材を減らすこ
とができるので、原子炉の建設コストを削減でき、ひい
ては原子炉の経済性を高めることができる。EFFECTS OF THE INVENTION According to the present invention, the work at the time of exchanging the control rod is easy, and the thickness of the lattice plate can be made thin to reduce the required materials. The economic efficiency of the furnace can be increased.
【図1】本発明に係る原子炉用上部格子板を原子炉圧力
容器内に組み込んだ状態を示す縦断面図。FIG. 1 is a vertical cross-sectional view showing a state in which a reactor upper lattice plate according to the present invention is incorporated in a reactor pressure vessel.
【図2】本発明に係る原子炉用上部格子板の第1の実施
例において第1の格子体と第2の格子体を分離した状態
を示す斜視図。FIG. 2 is a perspective view showing a state where the first lattice body and the second lattice body are separated in the first embodiment of the upper lattice plate for a nuclear reactor according to the present invention.
【図3】図2における原子炉用上部格子板内に挿入され
る燃料集合体と制御棒の配置状態の一例を示す縦断面
図。FIG. 3 is a vertical cross-sectional view showing an example of the arrangement of fuel assemblies and control rods inserted into the nuclear reactor upper lattice plate in FIG.
【図4】図2における原子炉用上部格子板内に燃料集合
体が挿入された状態を部分的に示す斜視図。FIG. 4 is a perspective view partially showing a state in which a fuel assembly is inserted into the nuclear reactor upper lattice plate in FIG. 2.
【図5】図2における原子炉用上部格子板内に挿入され
る燃料集合体と制御棒の配置状態の他の例を示す縦断面
図。5 is a vertical cross-sectional view showing another example of the arrangement state of the fuel assemblies and the control rods inserted into the nuclear reactor upper lattice plate in FIG.
【図6】(a)は本発明に係る原子炉用上部格子板の第
2の実施例を示す平面図、(b)は(a)における第1
の格子体を示す平面図、(c)は(a)における第2の
格子体を示す平面図。6A is a plan view showing a second embodiment of the upper lattice plate for a nuclear reactor according to the present invention, and FIG. 6B is a first view in FIG.
2A is a plan view showing the lattice body of FIG. 3C, and FIG.
【図7】本発明に適用される燃料集合体を一部切欠して
示す斜視図。FIG. 7 is a perspective view showing a fuel assembly applied to the present invention with a part thereof cut away.
【図8】本発明に係る原子炉用上部格子板の第3の実施
例における第1の格子体とその分割状態を示す平面図。FIG. 8 is a plan view showing a first lattice body and its divided state in a third embodiment of the upper lattice plate for a nuclear reactor according to the present invention.
【図9】従来の原子炉用上部格子板を一部切欠して示す
斜視図。FIG. 9 is a perspective view showing a conventional upper lattice plate for a nuclear reactor by partially cutting away.
【図10】(a)は図9の上部格子板の梁を組み立てる
前の状態を部分的に示す斜視図、(b)は(a)の状態
を押圧して組み立てた状態を部分的に示す斜視図。10A is a perspective view partially showing a state before assembling the beams of the upper lattice plate in FIG. 9, and FIG. 10B is a partial view showing a state where the state of FIG. Perspective view.
【図11】図9の原子炉用上部格子板内に挿入された燃
料集合体を示す横断面図。FIG. 11 is a cross-sectional view showing a fuel assembly inserted in the nuclear reactor upper lattice plate shown in FIG. 9;
【図12】図9の原子炉用上部格子板内に挿入された燃
料集合体と制御棒を概略的に示す横断面図。FIG. 12 is a cross-sectional view schematically showing a fuel assembly and control rods inserted into the nuclear reactor upper lattice plate of FIG.
1…上部格子板(従来例)、2,19…横梁、3,20…縦
梁、4…切り欠き部、5,22,44…燃料集合体、6…間
隔、7,23…制御棒、8…ナローギャップ、9…ワイド
ギャップ、10…チャンネルパッド、11…チャンネルファ
スナ、12…原子炉圧力容器、13…炉心シュラウド、14…
炉心、15…炉心支持板、16,40,45…第1の格子体、1
7,41…第2の格子体、18,39…上部格子体(本発
明)、21…開口部、24…制御棒駆動機構ハウジング、25
…大型チャンネルボックス、26…板状構造物、27…ウォ
ータロッド、28…燃料棒、29…板状構造物、30…非沸騰
領域、31…ダウンカマー、32…インターナルポンプ、33
…給水ノズル、34…給水スパージャ、35…気水分離器、
36…蒸気乾燥器、37…下部プレナム、38…蒸気出口ノズ
ル、42…ガイドピン、43…たて孔部。1 ... Upper lattice plate (conventional example), 2, 19 ... Horizontal beam, 3, 20 ... Vertical beam, 4 ... Notch part, 5, 22, 44 ... Fuel assembly, 6 ... Interval, 7, 23 ... Control rod, 8 ... Narrow gap, 9 ... Wide gap, 10 ... Channel pad, 11 ... Channel fastener, 12 ... Reactor pressure vessel, 13 ... Core shroud, 14 ...
Core, 15 ... Core support plate, 16, 40, 45 ... First lattice body, 1
7, 41 ... Second lattice body, 18, 39 ... Upper lattice body (present invention), 21 ... Opening portion, 24 ... Control rod drive mechanism housing, 25
… Large channel box, 26… plate structure, 27… water rod, 28… fuel rod, 29… plate structure, 30… non-boiling region, 31… downcomer, 32… internal pump, 33
… Water supply nozzle, 34… Water supply sparger, 35… Steam separator,
36 ... Steam dryer, 37 ... Lower plenum, 38 ... Steam outlet nozzle, 42 ... Guide pin, 43 ... Vertical hole.
Claims (1)
に組み込まれ複数の燃料集合体の上端を保持する原子炉
用上部格子板において、横梁と縦梁とによって格子状に
組まれた第1の格子体と第2の格子体とを積層し一体化
固定してなることを特徴とする原子炉用上部格子板。1. An upper lattice plate for a reactor, which is incorporated in an upper portion of a core shroud in a reactor pressure vessel and holds upper ends of a plurality of fuel assemblies, wherein the first lattice plates are assembled by horizontal beams and vertical beams. An upper lattice plate for a nuclear reactor, characterized in that the lattice body and the second lattice body are laminated and integrally fixed.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3289796A JPH05126978A (en) | 1991-11-06 | 1991-11-06 | Upper grid plate for nuclear reactor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3289796A JPH05126978A (en) | 1991-11-06 | 1991-11-06 | Upper grid plate for nuclear reactor |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH05126978A true JPH05126978A (en) | 1993-05-25 |
Family
ID=17747884
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3289796A Pending JPH05126978A (en) | 1991-11-06 | 1991-11-06 | Upper grid plate for nuclear reactor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH05126978A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100854769B1 (en) * | 2006-12-01 | 2008-08-27 | 한국원자력연구원 | Fixed unit of neclear feul manifold and reactor core the same |
KR101102127B1 (en) * | 2010-06-16 | 2012-01-03 | 두산중공업 주식회사 | Performance Test Apparatus for Head assembly of Nuclear Reactor |
-
1991
- 1991-11-06 JP JP3289796A patent/JPH05126978A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100854769B1 (en) * | 2006-12-01 | 2008-08-27 | 한국원자력연구원 | Fixed unit of neclear feul manifold and reactor core the same |
KR101102127B1 (en) * | 2010-06-16 | 2012-01-03 | 두산중공업 주식회사 | Performance Test Apparatus for Head assembly of Nuclear Reactor |
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