JPH05164865A - Fuel assembly - Google Patents
Fuel assemblyInfo
- Publication number
- JPH05164865A JPH05164865A JP3334729A JP33472991A JPH05164865A JP H05164865 A JPH05164865 A JP H05164865A JP 3334729 A JP3334729 A JP 3334729A JP 33472991 A JP33472991 A JP 33472991A JP H05164865 A JPH05164865 A JP H05164865A
- Authority
- JP
- Japan
- Prior art keywords
- fuel rod
- fuel
- end plug
- tie plate
- short
- 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、原子炉の燃料集合体に
係り、特に、燃料棒の長さが短い短尺燃料棒または燃料
棒の上端が支持または固定されていない燃料棒の、運転
中における浮き上がりおよび運搬中における移動を防止
する燃料集合体に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel assembly of a nuclear reactor, and more particularly to a short fuel rod having a short fuel rod or a fuel rod in which an upper end of the fuel rod is not supported or fixed. The present invention relates to a fuel assembly that prevents floating and movement during transportation.
【０００２】[0002]
【従来の技術】原子炉用燃料集合体は、図２に示すよう
に複数本の燃料棒を整列保持し、横方向の振動を拘束す
るスペーサ，燃料棒の上部端栓を支持する上部タイプレ
ート，下部端栓を支持する下部タイプレート、および、
これらの部材で組み立てられた燃料バンドルを収納する
チャンネルボックス（図示せず）で構成されている。2. Description of the Related Art As shown in FIG. 2, a fuel assembly for a nuclear reactor has an upper tie plate which holds a plurality of fuel rods in an aligned manner, restrains lateral vibrations, and supports upper end plugs of the fuel rods. ， The lower tie plate supporting the lower end plug, and
It is configured by a channel box (not shown) that accommodates a fuel bundle assembled with these members.
【０００３】ところで、放射線被爆量低減の観点から、
燃料サイクルの長期化を図る高燃焼度燃料集合体の開発
が行われている。ウラン装荷量を増加させる方法とし
て、燃料棒を細径にして本数を増やすことが考えられて
いる。しかし、燃料棒の本数が増えると燃料集合体の圧
力損失が増えることになる。そこで、低圧損化の一方法
として、燃料棒の一部に、従来の燃料棒の約半分の長さ
をもつ短尺燃料棒を配列することが提案されている（例
えば特開平2−140689 号公報）。From the viewpoint of reducing the radiation exposure,
High burnup fuel assemblies are being developed to prolong the fuel cycle. As a method of increasing the amount of uranium loaded, it is considered to reduce the number of fuel rods to increase the number. However, as the number of fuel rods increases, the pressure loss of the fuel assembly also increases. Therefore, as one method of reducing the low pressure loss, it has been proposed to arrange a short fuel rod having a length about half that of a conventional fuel rod in a part of the fuel rod (for example, Japanese Patent Laid-Open No. 140689/1990). ).
【０００４】[0004]
【発明が解決しようとする課題】しかし、従来の燃料集
合体に上記の短尺燃料棒をその一部に採用した場合、従
来の上部タイプレートではその上端が支持できなくな
る。すなわち、上，下部タイプレート間を結合している
結合燃料棒以外の通常の長尺な燃料棒と下部タイプレー
トとの結合構成は、図３に示すように下部端栓に設けて
ある丸軸を下部タイプレートの燃料棒の挿入穴に嵌合さ
せただけの構造である。そのため、上部タイプレートに
その上端が支持できなくなった短尺燃料棒は原子炉運転
中の浮き上がりおよび運搬中での移動があり、その健全
性に問題が生じる可能性があった。However, when the above-mentioned short fuel rod is adopted as a part of the conventional fuel assembly, the upper end of the conventional upper tie plate cannot be supported. That is, as shown in FIG. 3, the conventional long fuel rods other than the joined fuel rods connecting the upper and lower tie plates and the lower tie plate are connected to each other by a round shaft provided in the lower end plug. Is simply fitted into the insertion hole of the lower tie plate fuel rod. Therefore, the short fuel rods whose upper ends cannot be supported by the upper tie plate may float during the operation of the reactor and move during transportation, which may cause a problem in the soundness.
【０００５】本発明の目的は、短尺燃料棒を一部に備え
た燃料集合体において、この短尺燃料棒の原子炉運転中
における浮き上がりおよび運搬中における移動を防止す
る機構を設けた燃料集合体を提供することにある。An object of the present invention is to provide a fuel assembly provided with a part of a short fuel rod, which is provided with a mechanism for preventing the short fuel rod from being lifted up during a reactor operation and moved during transportation. To provide.
【０００６】[0006]
【課題を解決するための手段】短尺燃料棒の下部端栓の
根元部分にスプリングを設け、さらに、下部端栓の先端
部分に回転止めピンを設ける。そして、短尺燃料棒の下
部端栓が挿入されるべく位置の下部タイプレートの挿入
孔に、溝とグリッドの裏面に回転止めピンの固定用の溝
を設ける。A spring is provided at the base of the lower end plug of a short fuel rod, and a rotation stop pin is provided at the tip of the lower end plug. Then, a groove for fixing the rotation stop pin is provided on the back surface of the groove and the grid in the insertion hole of the lower tie plate where the lower end plug of the short fuel rod is inserted.
【０００７】[0007]
【作用】上記短尺燃料棒と下部タイプレートを嵌合させ
ることにより、原子炉運転中における短尺燃料棒の浮き
上がりおよび運搬中における移動を防止できる。By fitting the short fuel rod and the lower tie plate, it is possible to prevent the short fuel rod from being lifted up during operation of the reactor and moved during transportation.
【０００８】[0008]
【実施例】以下、本発明の一実施例を図１，図２，図
４，図５及び図６により説明する。本発明に係る燃料集
合体の全体構成を図２に示す。原子炉用燃料集合体にお
ける複数の燃料棒４は正方格子状に配列されている。燃
料棒４は上端が上部端栓を上部タイプレート１で、下端
は下部端栓７を下部タイプレート２にて支持され、両タ
イプレート間を複数のスペーサ３により整列保持されて
いる。燃料棒の一部は、短尺燃料棒６で構成されてい
る。短尺燃料棒６の構成を図４に示す。短尺燃料棒６の
下部端栓７の丸軸部において、下部端栓７の根元部分に
スプリング９を点溶接１３で固定し、かつ、下部端栓７
の先端部分には矩形型の突起物の回転止めピン１０を設
けてある。そして図５に示すように、短尺燃料棒６の下
部端栓７が挿入されるべく位置の下部タイプレート２の
挿入孔８には、短尺燃料棒６に設けられた回転止めピン
１０がグリッド１５の表面から裏面まで通過できる溝１
１と挿入孔周辺のグリッド１５裏面には溝と１８０度反
対側に回転止めピン固定溝１２が設けられている。図１
は、本発明の短尺燃料棒６と下部タイプレート２の嵌合
状況を示したものである。図１により、短尺燃料棒６の
装着手順を具体的に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1, 2, 4, 5, and 6. The overall structure of the fuel assembly according to the present invention is shown in FIG. The plurality of fuel rods 4 in the fuel assembly for a nuclear reactor are arranged in a square lattice. The fuel rod 4 has its upper end supported by the upper tie plate 1 at the upper end plug, and has the lower end supported by the lower tie plate 2 at the lower end plug 7, and the two tie plates are aligned and held by the plurality of spacers 3. Part of the fuel rods is composed of short fuel rods 6. The structure of the short fuel rod 6 is shown in FIG. In the round shaft portion of the lower end plug 7 of the short fuel rod 6, the spring 9 is fixed to the root portion of the lower end plug 7 by spot welding 13, and the lower end plug 7
A rotation stopper pin 10 of a rectangular protrusion is provided at the tip of the. Then, as shown in FIG. 5, in the insertion hole 8 of the lower tie plate 2 at the position where the lower end plug 7 of the short fuel rod 6 is to be inserted, the rotation stopping pin 10 provided on the short fuel rod 6 is arranged in the grid 15. Groove 1 that can pass from the front surface to the back surface
A rotation stopper pin fixing groove 12 is provided on the back surface of the grid 15 around the insertion hole 1 and the insertion hole on the side opposite to the groove by 180 degrees. Figure 1
[Fig. 4] shows a fitting state of the short fuel rod 6 and the lower tie plate 2 of the present invention. A procedure for mounting the short fuel rods 6 will be specifically described with reference to FIG.
【０００９】（１） 短尺燃料棒６が挿入されるべく位
置の下部タイプレート２の挿入孔８に、上部から短尺燃
料棒６の下部端栓７を挿入させる。その時、回転止めピ
ン１０と挿入孔８の溝位置１１を一致させる。(1) The lower end plug 7 of the short fuel rod 6 is inserted from above into the insertion hole 8 of the lower tie plate 2 at the position where the short fuel rod 6 is inserted. At that time, the rotation stop pin 10 and the groove position 11 of the insertion hole 8 are aligned.
【００１０】（２）さらに挿入して、スプリング９を押
し縮めて回転止めピン１０をグリッド１５の裏面まで貫
通させる。(2) Further insertion, the spring 9 is pressed and contracted so that the rotation stopping pin 10 penetrates to the back surface of the grid 15.
【００１１】（３）スプリング９を押し縮めたままで回
転止めピン１０の位置を１８０度回転させて反対側の回
転防止ピン固定溝１２に落し入れて固定する。(3) While the spring 9 is being compressed, the position of the rotation stopping pin 10 is rotated by 180 degrees and dropped into the rotation preventing pin fixing groove 12 on the opposite side to be fixed.
【００１２】（４）スプリング９の力により、短尺燃料
棒６は下部タイプレート２に確実に固定される。(4) Due to the force of the spring 9, the short fuel rod 6 is securely fixed to the lower tie plate 2.
【００１３】また、図６は、短尺燃料棒６の構成を示し
たもので、下部端栓７の根元部分に設けたスプリング９
をコイルスプリング９の変わりにプレートスプリング１
４を用いた変形例である。FIG. 6 shows the structure of the short fuel rod 6, in which a spring 9 provided at the root of the lower end plug 7 is provided.
Instead of coil spring 9 plate spring 1
4 is a modified example using 4.
【００１４】[0014]
【発明の効果】本発明によれば、燃料集合体の原子炉運
転中における短尺燃料棒の浮き上がりを防止し、運搬中
における移動を防止して燃料集合体の健全性を向上させ
ることができる。According to the present invention, the short length of the fuel rod can be prevented from being lifted up during the operation of the fuel assembly in the reactor and the movement of the fuel assembly during the transportation can be prevented so that the integrity of the fuel assembly can be improved.
【図１】本発明の一実施例を示す短尺燃料棒と下部タイ
プレートとの組立て状態を示す断面図。FIG. 1 is a sectional view showing an assembled state of a short fuel rod and a lower tie plate showing an embodiment of the present invention.
【図２】燃料集合体の全体構成を示す断面図。FIG. 2 is a sectional view showing the overall structure of a fuel assembly.
【図３】従来の短尺燃料棒と下部タイプレートとの組立
て状態を示す説明図。FIG. 3 is an explanatory view showing an assembled state of a conventional short fuel rod and a lower tie plate.
【図４】本発明の短尺燃料棒の構造を示す説明図。FIG. 4 is an explanatory view showing the structure of a short fuel rod of the present invention.
【図５】本発明の下部タイプレートの構造を示す断面
図。FIG. 5 is a sectional view showing the structure of the lower tie plate of the present invention.
【図６】本発明の短尺燃料棒の変形構造を示す説明図。FIG. 6 is an explanatory view showing a modified structure of the short fuel rod of the present invention.
２…下部タイプレート、４…長尺燃料棒、６…短尺燃料
棒、７…下部端栓、８…燃料棒挿入孔、９…スプリン
グ、１０…回転止めピン、１１…溝、１２…回転止めピ
ン固定溝、１３…点溶接。2 ... Lower tie plate, 4 ... Long fuel rod, 6 ... Short fuel rod, 7 ... Lower end plug, 8 ... Fuel rod insertion hole, 9 ... Spring, 10 ... Rotation stop pin, 11 ... Groove, 12 ... Rotation stop Pin fixing groove, 13 ... Spot welding.
フロントページの続き (72)発明者 中島 潤二郎 茨城県日立市幸町三丁目１番１号 株式会 社日立製作所日立工場内 (72)発明者 金森 健児 茨城県日立市幸町三丁目１番１号 株式会 社日立製作所日立工場内Front Page Continuation (72) Inventor Junjiro Nakajima 1-1-1, Sachimachi, Hitachi, Ibaraki Hitachi Ltd. Hitachi factory (72) Inventor Kenji Kanamori 3-1-1, Sachimachi, Hitachi, Ibaraki Stock company Hitachi Ltd.Hitachi factory
Claims (1)
ペーサ，下部タイプレートにより結合されている燃料バ
ンドルと、これらを収納するチャンネルボックスで構成
された燃料集合体において、短尺燃料棒の下部端栓の根
元部分にスプリングを設け、かつ、前記下部端栓の先端
部分に回転止めピンを設け、前記短尺燃料棒の前記下部
端栓が挿入されるべく位置の下部タイプレートの挿入孔
に、溝と前記回転止めピンの固定溝を設けたことを特徴
とする燃料集合体。1. A fuel assembly comprising a fuel bundle in which a plurality of fuel rods are joined by an upper tie plate, a spacer, and a lower tie plate, and a channel assembly for housing these fuel bundles. A spring is provided at the base portion of the end plug, and a rotation stop pin is provided at the tip portion of the lower end plug, and the insertion hole of the lower tie plate at the position where the lower end plug of the short fuel rod is to be inserted, A fuel assembly comprising a groove and a fixing groove for fixing the rotation stop pin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3334729A JPH05164865A (en) | 1991-12-18 | 1991-12-18 | Fuel assembly |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3334729A JPH05164865A (en) | 1991-12-18 | 1991-12-18 | Fuel assembly |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05164865A true JPH05164865A (en) | 1993-06-29 |
Family
ID=18280567
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3334729A Pending JPH05164865A (en) | 1991-12-18 | 1991-12-18 | Fuel assembly |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05164865A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6226343B1 (en) * | 1995-10-12 | 2001-05-01 | General Electric Company | Water rod in a fuel assembly of a boiling water nuclear reactor |
-
1991
- 1991-12-18 JP JP3334729A patent/JPH05164865A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6226343B1 (en) * | 1995-10-12 | 2001-05-01 | General Electric Company | Water rod in a fuel assembly of a boiling water nuclear reactor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4544522A (en) | Nuclear fuel assembly spacer | |
| US4885127A (en) | Nuclear fuel rod support grid with attachable spring and dimple support spacers | |
| US4585616A (en) | Nuclear fuel spacer grid with improved outer straps | |
| US4357298A (en) | Nuclear fuel assembly space arrangement | |
| JPS63285490A (en) | Fragment filter lower nozzle in fuel aggregate | |
| KR101072381B1 (en) | Top nozzle assembly having improved hold down performance in a fuel assembly of a nuclear reactor | |
| JPS6290594A (en) | Splinter capture device in fuel aggregate | |
| US4389369A (en) | Bi-metallic grid for a nuclear reactor fuel assembly | |
| US4585615A (en) | Nuclear fuel spacer grid with improved grid straps | |
| JPH08278393A (en) | Repairing method of fuel assembly with damaged fuel rod and spacer | |
| US4571324A (en) | Nuclear fuel assembly spacer | |
| US4587704A (en) | Method of mounting a continuous loop spring on a nuclear fuel spacer | |
| JPH036492A (en) | Upper nozzle sub-assembly of nuclear fuel aggregate | |
| EP0797217B1 (en) | Spacer capture mechanism for non-round water rods | |
| JPH05164865A (en) | Fuel assembly | |
| JP3364526B2 (en) | Fuel bundle | |
| JP3108189B2 (en) | Top nozzle of nuclear fuel assembly | |
| JPS61788A (en) | Holddown device for fuel aggregate of nuclear reactor | |
| US6285729B1 (en) | Fuel spacer/water rod capture apparatus and methods for boiling water nuclear reactors | |
| JPH02140689A (en) | Fuel assembly | |
| JP2884107B2 (en) | Fuel assembly | |
| JPH0312588A (en) | Fuel assembly | |
| JP2901685B2 (en) | Fuel assemblies and reactors | |
| JPS60152983A (en) | Nuclear fuel aggregate | |
| JPH02195295A (en) | Atomic fuel assembly |