JPH0616377Y2 - Flammable poison stick - Google Patents
Flammable poison stickInfo
- Publication number
- JPH0616377Y2 JPH0616377Y2 JP1987154792U JP15479287U JPH0616377Y2 JP H0616377 Y2 JPH0616377 Y2 JP H0616377Y2 JP 1987154792 U JP1987154792 U JP 1987154792U JP 15479287 U JP15479287 U JP 15479287U JP H0616377 Y2 JPH0616377 Y2 JP H0616377Y2
- Authority
- JP
- Japan
- Prior art keywords
- pipe
- plug
- end plug
- contact
- inner pipe
- 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.)
- Expired - Lifetime
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
- Butt Welding And Welding Of Specific Article (AREA)
Description
【考案の詳細な説明】 「産業上の利用分野」 この考案は原子炉内において初期過剰となっている反応
度を抑制するために使用される可燃性毒物棒に関する。DETAILED DESCRIPTION OF THE INVENTION "Industrial Application" This invention relates to a burnable poison rod used to control the initial excess reactivity in a nuclear reactor.
「従来の技術」 原子炉に装荷される燃料集合体は、上下方向に離間して
対向配置された上部ノズルと下部ノズルとの間に多数の
長尺な燃料棒を所定間隔をおいて互いに平行にまとめた
ものであるが、この燃料集合体には、原子炉内において
初期過剰となっている反応度を抑制するための可燃性毒
物棒が備えられている。“Prior Art” A fuel assembly loaded in a nuclear reactor has a large number of long fuel rods parallel to each other at a predetermined interval between an upper nozzle and a lower nozzle which are vertically opposed to each other. The fuel assembly is equipped with a burnable poison rod for suppressing the reactivity that is initially excessive in the reactor.
この可燃性毒物棒の一例を第４図および第５図に示す。
これら図において符号１は可燃性毒物棒の外管を示す。
この外管１の内部には内管２が外管１と隙間を隔てて同
心に配置されており、外管１と内管２との間に隙間には
リング状のペレット３……が外管１および内管２の軸線
方向に多数挿入されている。このペレット（可燃性毒
物）３は、炭化ホウ素一酸化アルミニウム（Ｂ４Ｃ−Ａ
ｌ２Ｏ３）からなる中性子吸収材であり、原子炉の運転
に伴い燃焼するようになっている。An example of this burnable poison rod is shown in FIGS. 4 and 5.
In these figures, reference numeral 1 indicates an outer tube of a burnable poison rod.
An inner tube 2 is concentrically arranged inside the outer tube 1 with a gap between the outer tube 1 and a ring-shaped pellet 3 ... A large number of tubes 1 and inner tubes 2 are inserted in the axial direction. This pellet (combustible poison) 3 is boron carbide aluminum monoxide (B 4 C-A).
It is a neutron absorber made of 1 2 O 3 ) and burns with the operation of the nuclear reactor.
また、上記内管２の開口端面2aは外管１の開口端面1aよ
り図中左方に位置しており、各開口部は端栓５により閉
塞されている。The opening end surface 2a of the inner tube 2 is located to the left of the opening end surface 1a of the outer tube 1 in the figure, and each opening is closed by an end plug 5.
この端栓５は外管１に挿入される外栓６と、この外栓６
の図中左端面に同心にかつ外栓６より小径に形成され、
内管２に挿入される内栓７とから構成されている。The end plug 5 includes an outer plug 6 to be inserted into the outer tube 1, and the outer plug 6
Is formed concentrically on the left end face in the figure and having a smaller diameter than the outer plug 6,
It is composed of an inner plug 7 that is inserted into the inner tube 2.
外栓６の図中左端部外周面には、この外周面を周方向に
沿って切り欠いてなる挿入部6aが形成されており、この
挿入部6aの右端には上記外管１の開口端面1aに当接する
当接面６ｂが形成されている。On the outer peripheral surface of the left end portion in the figure of the outer plug 6, an insertion portion 6a is formed by cutting the outer peripheral surface in the circumferential direction, and the opening end surface of the outer tube 1 is formed on the right end of the insertion portion 6a. A contact surface 6b that contacts the 1a is formed.
一方、上記内栓７の図中左端部外周面には、この外周面
を周方向に沿って切り欠いてなる挿入部7aが形成されて
おり、この挿入部7aの右端には上記内管２の開口端面2a
に当接する当接面7bが形成されている。On the other hand, on the outer peripheral surface of the left end portion of the inner plug 7 in the figure, an insertion portion 7a is formed by cutting out the outer peripheral surface in the circumferential direction, and the inner pipe 2 is formed at the right end of the insertion portion 7a. Open end face 2a
A contact surface 7b is formed which abuts against.
また、端栓５の中心部には、原子炉内において冷却水を
内管２内を流通させるための貫通孔８が形成されてい
る。Further, a through hole 8 for allowing cooling water to flow through the inner pipe 2 in the reactor is formed in the center of the end plug 5.
そして、上記構成の可燃性毒物棒は、内管２の外周にペ
レット３をはめ込み、内管２の開口部に端栓５の内栓７
の挿入部7aを挿入して、内管２の開口端面2aと内栓７の
当接面7bとの当接部を周方向に沿って溶接（溶接部１０
を形成）し、その後、外管１の開口部に外栓６の挿入部
6aを挿入して、外管１の開口端面1aと外栓６の当接面6b
との当接部を周方向に沿って溶接（溶接部１１を形成）
することにより組み立てられる。Then, the burnable poison rod having the above-mentioned configuration is such that the pellet 3 is fitted into the outer periphery of the inner pipe 2, and the inner plug 7 of the end plug 5 is inserted into the opening of the inner pipe 2.
Of the inner pipe 2 and the contact portion between the contact surface 7b of the inner plug 7 are welded along the circumferential direction (weld portion 10).
And then insert the outer plug 6 into the opening of the outer tube 1.
Inserting 6a, the open end surface 1a of the outer tube 1 and the contact surface 6b of the outer plug 6
Weld the contact part with and along the circumferential direction (form the welded part 11)
It is assembled by doing.
「考案が解決しようとする問題点」 ところで、上記構成の可燃性毒物棒においては、それを
組み立てる際に、端栓５の内栓７の当接面7bと内管２の
開口端面2aとの当接部を溶接する作業、および外栓６の
当接面6bと外管１の開口端面1aとの当接部を溶接する作
業の２つの溶接作業を必要とするので、組み立てに手間
がかかると共に、溶接部１０，１１の検査も２回行わな
ければならないので、生産性が低いという問題があっ
た。"Problems to be solved by the invention" By the way, in the combustible poison rod having the above structure, when assembling it, the contact surface 7b of the inner plug 7 of the end plug 5 and the opening end surface 2a of the inner pipe 2 Two welding operations, one for welding the abutting portion and the other for the abutting portion between the abutting surface 6b of the outer plug 6 and the opening end surface 1a of the outer tube 1, are required, so that assembly is troublesome. At the same time, since the welded portions 10 and 11 must be inspected twice, there is a problem that productivity is low.
また、端栓５の内栓７の当接面7bと内管２の開口端面2a
との当接部を溶接した後に、外栓６の当接面6bと外管１
の開口端面1aとの当接部を溶接するので、当接面7aと内
管２の開口端面2aとの溶接部１０において、端栓５およ
び内管２に熱による変形が生じると、外管１に端栓５の
外栓６を挿入し難くになったり、外管１、内管２および
端栓５のそれぞれの軸心がずれたりして、歩留まりが非
常に悪いという問題があった。Also, the contact surface 7b of the inner plug 7 of the end plug 5 and the opening end surface 2a of the inner pipe 2
After welding the abutting portion with the abutment surface 6b of the outer plug 6 and the outer tube 1
Since the contact portion of the contact surface 7a with the opening end surface 1a is welded, if the end plug 5 and the inner tube 2 are deformed by heat at the weld portion 10 between the contact surface 7a and the opening end surface 2a of the inner tube 2, the outer tube Since it becomes difficult to insert the outer plug 6 of the end plug 5 into 1 and the axial centers of the outer pipe 1, the inner pipe 2 and the end plug 5 are displaced, there is a problem that the yield is very poor.
この考案は、上記問題点を解決することを目的としてい
る。This invention aims at solving the above-mentioned problems.
「問題点を解決するための手段」 この考案の可燃性毒物棒は、外管と内管とのそれぞれの
開口端部を二重管の軸線方向において同一位置に配置す
ると共に、外管の開口端面と端栓の当接面との当接部に
形成される溶接部が、内管の開口端面と端栓の当接面と
の当接部まで延びていることを特徴としている。[Means for Solving the Problems] In the burnable poison rod of the present invention, the open ends of the outer pipe and the inner pipe are arranged at the same position in the axial direction of the double pipe, and the open pipe of the outer pipe is opened. The welded portion formed at the contact portion between the end surface and the contact surface of the end plug extends to the contact portion between the open end surface of the inner pipe and the contact surface of the end plug.
「作用」 この考案の可燃性毒物棒にあっては、外管の開口端部と
内管の開口端部とを二重管の軸線方向において同一位置
に配置し、外管の開口端面と端栓の当接面との当接部
に、この当接部から内管の開口端面と端栓の当接面との
当接部まで延びる溶接部を一体的に形成したので、二重
管と端栓との溶接作業を１回で行うことができ、この結
果生産性および歩留まりを向上させることができる。[Operation] In the burnable poison rod of the present invention, the opening end of the outer pipe and the opening end of the inner pipe are arranged at the same position in the axial direction of the double pipe, and the opening end face and the end of the outer pipe are arranged. Since a welded portion extending from this contact portion to the contact portion between the opening end surface of the inner pipe and the contact surface of the end plug is integrally formed at the contact portion with the contact surface of the plug, the double pipe and The welding operation with the end plug can be performed once, and as a result, the productivity and the yield can be improved.
「実施例」 以下この考案の一実施例を第１図および第２図を参照し
て説明する。[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
これらの図において符号１０は二重管、符号１１は端栓
を示す。上記二重管１０は外管１２と、この外管１２の
内部に所定の隙間を隔てて同心に配置された内管１３と
から構成されており、外管１２の開口端面12aと内管１
３の開口端面13aとは二重管１０の軸線方向において同
一位置に位置している。なお、外管１２と内管１３との
間には上記ペレット３が挿入されている。In these figures, reference numeral 10 indicates a double pipe and reference numeral 11 indicates an end plug. The double pipe 10 is composed of an outer pipe 12 and an inner pipe 13 which is concentrically arranged inside the outer pipe 12 with a predetermined gap therebetween. The open end face 12a of the outer pipe 12 and the inner pipe 1 are formed.
The opening end face 13a of the No. 3 is located at the same position in the axial direction of the double pipe 10. The pellet 3 is inserted between the outer tube 12 and the inner tube 13.
また、上記端栓１１は第２図に示すように、略半球状の
栓本体１５と、その図中左面に形成され、内管１３に挿
入される筒状の挿入部１６と、この挿入部１６の外側に
形成され、外管１２と内管１３との間のに挿入されるリ
ング状の環部１８とにより構成されている。そして、環
部１８の外側に位置する栓本体１５の左面が外管１２の
開口端面12aに当接する当接面１９とされており、環部
１８の内側に位置する栓本体１５の左面が内管１３の開
口端面13aに当接する当接面２０とされている。As shown in FIG. 2, the end plug 11 has a substantially hemispherical plug body 15, a cylindrical insertion portion 16 formed on the left side in the drawing and inserted into the inner pipe 13, and this insertion portion. A ring-shaped ring portion 18 is formed on the outer side of 16 and is inserted between the outer tube 12 and the inner tube 13. The left surface of the plug body 15 located outside the ring portion 18 is the contact surface 19 that contacts the open end surface 12a of the outer tube 12, and the left surface of the plug body 15 located inside the ring portion 18 is the inner surface. The contact surface 20 contacts the open end surface 13a of the tube 13.
また上記端栓１１の中央部には図中左右方向に延びる貫
通孔２１が形成されている。Further, a through hole 21 extending in the left-right direction in the drawing is formed in the central portion of the end plug 11.
そして、この発明の可燃性毒物棒は、第２図に示すよう
に、内管１３に端栓１１の挿入部１６を、内管１３と外
管１２との間に環部１８を挿入すると共に、内管１３の
開口端面13aに栓本体１５の当接面２０を、外管１２の
開口端面12aに当接面１９を当接させて、第１図に示す
ように、外管１２の開口端面12aと端栓１１の当接面１
９との当接部に、この当接部から内管１３の開口端面13
aと当接面２０との当接部まで延びる溶接部２１を形成
することにより、これら当接部が一体的に溶接されてい
る。The burnable poison rod of the present invention, as shown in FIG. 2, inserts the insertion portion 16 of the end plug 11 into the inner pipe 13 and the ring portion 18 between the inner pipe 13 and the outer pipe 12. The contact surface 20 of the plug body 15 is brought into contact with the opening end surface 13a of the inner tube 13 and the contact surface 19 is brought into contact with the opening end surface 12a of the outer tube 12 to open the outer tube 12 as shown in FIG. Contact surface 1 between end surface 12a and end plug 11
9 and the opening end surface 13 of the inner pipe 13 from this contact portion.
By forming a welded portion 21 that extends to the contact portion between a and the contact surface 20, these contact portions are integrally welded.
上記構成の可燃性毒物棒によれば、外管１２の開口端面
12aと内管１３の開口端面13aとを二重管１０の軸線方向
において同一位置に配置し、外管１２の開口端面12aと
端栓１１の当接面１９との当接部に、この当接部から内
管１３の開口端面13aと端栓１１の当接面２０との当接
部まで延びる溶接部２１を一体的に形成したので、二重
管１０と端栓１１との溶接作業を１回で行うことができ
る。したがって、可燃性毒物棒の組み立ておよび溶接部
２１検査を従来より容易に行うことができ、よって生産
性を向上させることができる。According to the burnable poison rod having the above structure, the open end surface of the outer tube 12
12a and the opening end surface 13a of the inner tube 13 are arranged at the same position in the axial direction of the double tube 10, and the contact portion between the opening end surface 12a of the outer tube 12 and the contact surface 19 of the end plug 11 is provided with this contact. Since the welded portion 21 extending from the contact portion to the contact portion between the open end surface 13a of the inner pipe 13 and the contact surface 20 of the end plug 11 is integrally formed, the welding work of the double pipe 10 and the end plug 11 can be performed. It can be done once. Therefore, the assembling of the burnable poison rod and the inspection of the welded portion 21 can be performed more easily than before, and thus the productivity can be improved.
また、二重管１０と端栓１５との溶接を１回で行うこと
ができるので、従来のように、端栓５および内管２に熱
による変形が生じて、外管１に端栓５の外栓６を挿入し
難くになったり、外管１、内管２および端栓５のそれぞ
れの軸心がずれたりすることがなく、よって歩留まりを
向上させることができる。Moreover, since the double pipe 10 and the end plug 15 can be welded once, the end plug 5 and the inner pipe 2 are deformed by heat, and the outer pipe 1 is welded to the end plug 5 as in the conventional case. It becomes difficult to insert the outer plug 6 and the respective axial centers of the outer tube 1, the inner tube 2 and the end plug 5 are not displaced, so that the yield can be improved.
「他の実施例」 第３図はこの考案の他の実施例を示すものであり、第１
図および第２図に示すものと異なる点は端栓の形状であ
る。[Other Embodiments] FIG. 3 shows another embodiment of the present invention.
The point different from those shown in FIGS. 2 and 3 is the shape of the end plug.
すなわち、第３図に示す端栓３０は、第１図および第２
図に示す端栓１１から環部１８を切り離したものであ
る。そして、この端栓３０を用いた可燃性毒物棒では、
外管１２と内管１３との間に環部１８の代わりにリング
状の中子３１が挿入された上で端栓３０と二重管１０と
が上記と同様にして溶接されている。That is, the end plug 30 shown in FIG.
The ring portion 18 is separated from the end plug 11 shown in the figure. And with the burnable poison stick using this end plug 30,
A ring-shaped core 31 is inserted between the outer pipe 12 and the inner pipe 13 instead of the ring portion 18, and the end plug 30 and the double pipe 10 are welded in the same manner as above.
この実施例の可燃性毒物棒によれば、上記第一実施例の
可燃性毒物棒の効果に加えて、端栓３０の形状が簡単に
なるので、端栓３０を容易に製造することができるとい
う効果が得られる。According to the burnable poison rod of this embodiment, in addition to the effect of the burnable poison rod of the first embodiment, the end plug 30 has a simple shape, so that the end plug 30 can be easily manufactured. The effect is obtained.
「考案の効果」 以上説明したように、この考案の可燃性毒物棒によれ
ば、外管の開口端部と内管の開口端部とを二重管の軸線
方向において同一位置に配置し、外管の開口端面と端栓
の当接面との当接部に、この当接部から内管の開口端面
と端栓の当接面との当接部まで延びる溶接部を一体的に
形成したので、二重管と端栓との溶接作業を１回で行う
ことができる。したがって、可燃性毒物棒の組み立てお
よび溶接部の検査を従来より容易に行うことができ、よ
って生産性を向上させることができる。[Advantage of Device] As described above, according to the burnable poison rod of the present invention, the open end of the outer pipe and the open end of the inner pipe are arranged at the same position in the axial direction of the double pipe, A weld is integrally formed at the contact portion between the opening end surface of the outer pipe and the contact surface of the end plug, from this contact portion to the contact portion between the opening end surface of the inner pipe and the contact surface of the end plug. Therefore, the welding work of the double pipe and the end plug can be performed once. Therefore, the assembling of the burnable poison rod and the inspection of the welded portion can be carried out more easily than before, and the productivity can be improved.
また、二重管と端栓との溶接を１回で行うことができる
ので、従来のように、端栓および内管に変形が生じて、
外管に端栓を挿入し難くになったり、外管、内管および
端栓のそれぞれの軸心がずれたりすることがなく、よっ
て歩留まりを向上させることができる。In addition, since the double pipe and the end plug can be welded once, the end plug and the inner pipe are deformed as in the conventional case,
It is possible to improve the yield without making it difficult to insert the end plugs into the outer tube or shifting the respective axial centers of the outer tube, the inner tube and the end plugs.
第１図および第２図はこの考案の可燃性毒物棒の一実施
例を示すものであり、第１図は可燃性毒物棒の要部を示
す断面図、第２図は二重管と端栓とを溶接する前の要部
の断面図、第３図はこの考案の他の実施例を示すもので
あり、二重管と端栓とを溶接する前の要部の断面図、第
４図および第５図は従来の可燃性毒物棒の一例を示すも
のであり、第４図は可燃性毒物棒の要部の断面図、第５
図は二重管と端栓とを溶接する前の要部の断面図であ
る。 ３……可燃性毒物（ペレット）、１０……二重管、１１
……端栓、 １２……外管、12a……開口端面、 １３……内管、13a……開口端面、 １９，２０……当接面、２１……溶接部。FIGS. 1 and 2 show an embodiment of the burnable poison rod of the present invention. FIG. 1 is a sectional view showing a main part of the burnable poison rod, and FIG. 2 is a double pipe and an end. 4 is a cross-sectional view of the main part before welding the stopper, and FIG. 3 shows another embodiment of the present invention. FIG. 4 is a cross-sectional view of the main part before welding the double pipe and the end plug. 5 and 5 show an example of a conventional burnable poison rod, FIG. 4 is a cross-sectional view of a main portion of the burnable poison rod, FIG.
The figure is a cross-sectional view of a main part before welding the double pipe and the end plug. 3 ... Combustible poison (pellet), 10 ... Double pipe, 11
...... End plug, 12 …… Outer pipe, 12a …… Opening end face, 13 …… Inner pipe, 13a …… Opening end face, 19,20 …… Abutting surface, 21 …… Welding part.
Claims (1)
置された内管とからなる二重管であって、外管と内管と
の隙間に可燃性毒物が挿入され、二重管の開口端部に端
栓が挿入溶接されてなる可燃性毒物棒において、 上記外管と上記内管とのそれぞれの開口端部を上記二重
管の軸線方向において同一位置に配置すると共に、上記
外管の開口端面と上記端栓の当接面との当接部に形成さ
れる溶接部が、上記内管の開口端面と上記端栓の当接面
との当接部まで延びていることを特徴とする可燃性毒物
棒。1. A double pipe comprising an outer pipe and an inner pipe concentrically arranged in the outer pipe with a gap therebetween, wherein a burnable poison is inserted into the gap between the outer pipe and the inner pipe. In a burnable poison rod in which an end plug is inserted and welded into the open end of the heavy pipe, the open ends of the outer pipe and the inner pipe are arranged at the same position in the axial direction of the double pipe. A welding portion formed at a contact portion between the opening end surface of the outer pipe and the contact surface of the end plug extends to a contact portion between the opening end surface of the inner pipe and the contact surface of the end plug. A flammable poison stick characterized by being present.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1987154792U JPH0616377Y2 (en) | 1987-10-09 | 1987-10-09 | Flammable poison stick |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1987154792U JPH0616377Y2 (en) | 1987-10-09 | 1987-10-09 | Flammable poison stick |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0159897U JPH0159897U (en) | 1989-04-14 |
| JPH0616377Y2 true JPH0616377Y2 (en) | 1994-04-27 |
Family
ID=31431842
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1987154792U Expired - Lifetime JPH0616377Y2 (en) | 1987-10-09 | 1987-10-09 | Flammable poison stick |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0616377Y2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2017116504A (en) * | 2015-12-25 | 2017-06-29 | 三菱重工業株式会社 | Control rod aggregate for fuel storage pit |
| JP2019007916A (en) * | 2017-06-28 | 2019-01-17 | 三菱重工業株式会社 | Insertion object for fuel storage pit |
-
1987
- 1987-10-09 JP JP1987154792U patent/JPH0616377Y2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0159897U (en) | 1989-04-14 |
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