JP2016075630A - Reactor pressure vessel and mounting method of welding protection device - Google Patents

Reactor pressure vessel and mounting method of welding protection device Download PDF

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JP2016075630A
JP2016075630A JP2014207338A JP2014207338A JP2016075630A JP 2016075630 A JP2016075630 A JP 2016075630A JP 2014207338 A JP2014207338 A JP 2014207338A JP 2014207338 A JP2014207338 A JP 2014207338A JP 2016075630 A JP2016075630 A JP 2016075630A
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pressure vessel
reactor pressure
protection device
welded part
metal cover
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靖己 北島
Yasuki Kitajima
靖己 北島
一義 青木
Kazuyoshi Aoki
一義 青木
三男 小室
Mitsuo Komuro
三男 小室
忠浩 三橋
Tadahiro Mihashi
忠浩 三橋
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Toshiba Corp
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Toshiba Corp
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    • 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

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Abstract

PROBLEM TO BE SOLVED: To provide a welding protection device capable of preventing a reactor pressure vessel from getting damaged or being broken at weld part even if the core is melt down by protecting a weld part and a penetration part on a lower head of the pressure vessel.SOLUTION: A metal cover container 35, which is covered with a thermal insulation material 36, includes a welding protection device 33A which is disposed around the weld part 30 on a penetration part 28 of the reactor pressure vessel 10. The welding protection device 33A which has ribs 37 and levers as reinforcement members is disposed inside the metal cover container 35.SELECTED DRAWING: Figure 3

Description

本発明の実施形態は、溶接部の破損を防止する溶接部保護装置を備えた原子炉圧力容器およびその溶接部保護装置の取付方法に関する。   Embodiments described herein relate generally to a reactor pressure vessel including a welded part protection device that prevents damage to a welded part, and a method for attaching the welded part protective apparatus.

水冷却型原子炉では、原子炉圧力容器内への給水の停止や原子炉圧力容器に接続された配管の破断による冷却水が喪失すると、原子炉水位が低下して炉心が露出し、冷却が不充分になる可能性がある。炉心冷却が不充分な場合を想定して、水位低下信号を検出して原子炉を自動的に非常停止させ、非常用炉心冷却装置による冷却材の注入によって炉心を冠水させて冷却し、炉心溶融事故が生じるのを未然に防止している。   In a water-cooled nuclear reactor, if the cooling water is lost due to the stoppage of water supply to the reactor pressure vessel or the breakage of the piping connected to the reactor pressure vessel, the reactor water level is lowered and the core is exposed, and cooling is performed. It may be insufficient. Assuming inadequate core cooling, the reactor is automatically shut down by detecting a water level drop signal, and the core is submerged and cooled by injecting coolant using an emergency core cooling system, and the core melts. Accidents are prevented from occurring.

確率的には極めて低いが、非常用炉心冷却装置が何らかの原因で作動せず、かつ、その他の炉心への注水装置も利用できない事態も想定され得る。炉心への注水が不充分な場合には、原子炉水の低下により炉心冷却が充分に行なわれず、原子炉停止後も発生し続ける崩壊熱によって燃料棒温度が上昇し、最終的には炉心溶融に至る可能性が考えられる。   Although the probability is extremely low, it may be assumed that the emergency core cooling device does not operate for some reason and water injection devices for other cores cannot be used. If the water injection into the core is insufficient, the core water will not be sufficiently cooled due to the decrease in reactor water, and the fuel rod temperature will rise due to the decay heat that continues to occur even after the reactor shuts down. The possibility of reaching

炉心溶融が万一生じる場合には、高温の炉心溶融物が原子炉圧力容器下部に溶け落ち、さらに、圧力容器下鏡の貫通部を溶融貫通して格納容器内の床上に落下する可能性がある。格納容器床に落下する炉心溶融物は、格納容器床に張られたコンクリートを加熱し、接触面が高温状態になると、コンクリートと反応し、二酸化炭素、水素等の非凝縮正ガスを大量に発生させ、コンクリートを溶融浸食させる。発生した非凝縮ガスは格納容器内の圧力を高め、格納容器を破損させる可能性がある。また、コンクリートの溶融浸食により格納容器バウンダリを破損させる可能性がある。   In the unlikely event that core melting occurs, there is a possibility that the hot core melt melts down into the lower part of the reactor pressure vessel, and further melts through the penetration part of the lower pressure vessel mirror and falls onto the floor in the containment vessel. is there. The core melt that falls on the containment floor heats the concrete stretched on the containment floor and reacts with the concrete when the contact surface reaches a high temperature, generating a large amount of noncondensable positive gases such as carbon dioxide and hydrogen. To melt and erode the concrete. The generated non-condensable gas increases the pressure in the containment vessel and may damage the containment vessel. In addition, the containment boundary may be damaged by melting and erosion of concrete.

一方、炉心溶融が生じても、炉心溶融物を原子炉圧力容器内に保持することができれば、炉心溶融物とコンクリートとの反応等を回避でき、考慮する必要かせなくなる。この点から、万一炉心溶融が生じても、炉心溶融物を原子炉圧力容器内に封じ込めて保持し、冷却する手段が提案されている。   On the other hand, even if the core melts, if the core melt can be held in the reactor pressure vessel, the reaction between the core melt and the concrete can be avoided and it is not necessary to consider. From this point, even if a core melt occurs, a means for confining and holding the core melt in the reactor pressure vessel and cooling it has been proposed.

炉心溶融物を原子炉圧力容器内に保持する代表的な手法にＩＶＲ（Ｉｎ−Ｖｅｓｓｅｌ Ｒｅｔｅｎｓｉｏｎ）と呼ばれる手法がある。ＩＶＲは原子炉圧力容器上に落下した炉心溶融物が格納容器に流出するのを防止する手法である。これは、原子炉圧力容器を冷却水で外部冠水させ、炉心溶融物から伝わる熱を冷却水の沸騰熱伝達で除熱し、発生した蒸気を格納容器内で冷却して凝縮させ、凝縮水を原子炉圧力容器周りに戻すことにより（圧力容器下鏡上に溶け落ちた）炉心溶融物および原子炉圧力容器を冷却し、炉心溶融物の流出を防止するものである。   There is a technique called IVR (In-Vessel Retention) as a typical technique for holding the core melt in the reactor pressure vessel. IVR is a technique for preventing the core melt that has fallen onto the reactor pressure vessel from flowing out into the containment vessel. This is because the reactor pressure vessel is externally flooded with cooling water, the heat transferred from the core melt is removed by boiling water transfer of the cooling water, and the generated steam is cooled and condensed in the containment vessel, and the condensed water is atomized. By returning to the periphery of the reactor pressure vessel (melted down on the mirror under the pressure vessel), the core melt and the reactor pressure vessel are cooled to prevent the core melt from flowing out.

ＩＶＲを成立させるためには、炉心溶融物から原子炉圧力容器に伝わる熱によって原子炉圧力容器が破損するのを防ぐ必要がある。このため、炉心溶融物から伝わる熱が集中する位置の原子炉圧力容器内壁面に耐熱材を張り、原子炉圧力容器に伝わる熱を制限して、原子炉圧力容器の溶融・破損を防ぐ技術が特許文献１で知られている。   In order to establish IVR, it is necessary to prevent the reactor pressure vessel from being damaged by heat transferred from the core melt to the reactor pressure vessel. For this reason, a technology to prevent melting and breakage of the reactor pressure vessel by applying a heat-resistant material to the inner wall of the reactor pressure vessel at the position where the heat transmitted from the core melt is concentrated and limiting the heat transmitted to the reactor pressure vessel It is known from Patent Document 1.

また、原子炉圧力容器内に炉心溶融物を受け止める構造物を設置し、圧力容器下部の構造物を保護する技術も特許文献２で知られている。   Patent Document 2 also discloses a technique for installing a structure for receiving a core melt in a reactor pressure vessel and protecting the structure under the pressure vessel.

特表２０００−５０２８０８号公報Special Table 2000-502808 米国特許第６１９５４０５号Ｂ明細書US Pat. No. 6,195,405 B

炉心溶融が万一生じ、圧力容器下部ヘッド（圧力容器下鏡）上で炉心溶融物を保持しようとする場合、圧力容器下部ヘッドに存在する貫通部の溶接部を保護することが課題となる。   In the unlikely event that core melting occurs and the core melt is to be held on the pressure vessel lower head (pressure vessel lower mirror), it becomes a problem to protect the welded portion of the penetration portion existing in the pressure vessel lower head.

炉心溶融物が原子炉圧力容器内部に保持された状態で原子炉圧力容器が外部から冷却されている場合、原子炉圧力容器内側が高温の炉心溶融物によって溶融浸食される。このとき、原子炉圧力容器外部は冷却により圧力容器壁の健全性が維持されていても、図１１に示すように、原子炉圧力容器１は圧力容器下部ヘッド１ａから内部に突き出た位置に、貫通部２を通る部材３を支持する溶接部４が存在すると、溶接部４が溶融し易く、貫通部２を通る部材３が落下する可能性が大きい。貫通部材３が抜け落ちると、原子炉圧力容器１の貫通部２に口径の大きい破損孔が生じ、この破損孔を通して炉心溶融物が外部に流出し、流れ落ちてしまう。   When the reactor pressure vessel is cooled from the outside while the core melt is held inside the reactor pressure vessel, the inside of the reactor pressure vessel is melted and eroded by the hot core melt. At this time, even if the outside of the reactor pressure vessel maintains the soundness of the pressure vessel wall by cooling, as shown in FIG. 11, the reactor pressure vessel 1 protrudes from the pressure vessel lower head 1a to the inside. If the welded part 4 that supports the member 3 passing through the penetrating part 2 is present, the welded part 4 is likely to melt, and the member 3 passing through the penetrating part 2 is likely to fall. When the penetrating member 3 falls off, a broken hole having a large diameter is generated in the penetrating portion 2 of the reactor pressure vessel 1, and the core melt flows out through the broken hole and flows down.

特許文献１は、原子炉圧力容器の内壁に耐熱材を張って保護層を帯状に配置し、原子炉圧力容器の溶融・破損を防ぐ技術であるが、圧力容器下部ヘッドの貫通部を炉心溶融物から保護することはできない。   Patent Document 1 is a technology in which a heat-resistant material is stretched on the inner wall of a reactor pressure vessel and a protective layer is disposed in a band shape to prevent melting and breakage of the reactor pressure vessel. It cannot be protected from things.

また、特許文献２では、圧力容器下部ヘッド上に炉心溶融物を受け止めるギャップ構造物を設置し、原子炉圧力容器を貫通する構造物を保持することができるとされているが、ギャップ構造物が大型であるため、既設の原子炉に適用することが困難である。   Further, in Patent Document 2, it is said that a gap structure for receiving the core melt can be installed on the pressure vessel lower head and the structure penetrating the reactor pressure vessel can be held. Due to its large size, it is difficult to apply to existing reactors.

本発明の実施形態は、上述した事情を考慮してなされたもので、万一の炉心溶融時にも、原子炉圧力容器の溶接部の損傷・破損を防止することができる原子炉圧力容器およびその溶接部保護装置の取付方法を提供することを目的とする。   The embodiment of the present invention has been made in consideration of the above-described circumstances, and a reactor pressure vessel capable of preventing damage and breakage of a welded portion of the reactor pressure vessel even in the event of a core melt, and its It aims at providing the attachment method of a welding part protective device.

本発明に係る原子炉圧力容器は、上述した課題を解決するために、断熱材を覆った金属カバー容器を、原子炉圧力容器貫通部上の溶接部周囲に設置した溶接部保護装置を備え、前記溶接部保護装置は、前記金属カバー容器の内部に補剛部材のリブあるいはリバーが配設されたことを特徴とするものである。   In order to solve the above-described problems, a reactor pressure vessel according to the present invention includes a welded part protection device in which a metal cover container covering a heat insulating material is installed around a welded part on a reactor pressure vessel penetration part, The welded part protection device is characterized in that a rib or a river of a stiffening member is disposed inside the metal cover container.

また、本発明に係る原子炉圧力容器の溶接部保護装置の取付方法は、上述した課題を解決するために、原子炉圧力容器貫通部上の溶接部により貫通部材を固定する一方、断熱材を覆う金属カバー容器の内部に、補剛部材のリブあるいはリバーを配設した溶接部保護装置を準備し、前記貫通部材を固定する溶接部の周囲に前記溶接部保護装置を外側から覆うように設置して、前記溶接保護装置を取り付けることを特徴とする取付方法である。   Moreover, in order to solve the above-described problems, the method for attaching the reactor pressure vessel welded part protection apparatus according to the present invention fixes the penetration member by the welded part on the reactor pressure vessel penetration part, while providing the heat insulating material. Prepare a welded part protection device with ribs or rivers of stiffening members inside the metal cover container to cover, and install the welded part protection device from the outside around the welded part that fixes the penetrating member And it is the attachment method characterized by attaching the said welding protection apparatus.

本発明においては、万一の炉心溶融時にも、原子炉圧力容器の溶接部の溶融を防止して、溶接部の損傷・破損を防止することができる。   In the present invention, even in the unlikely event of melting of the core, melting of the welded portion of the reactor pressure vessel can be prevented, and damage / breakage of the welded portion can be prevented.

原子炉圧力容器の構成を示す縦断面図。The longitudinal cross-sectional view which shows the structure of a nuclear reactor pressure vessel. 原子炉圧力容器貫通部と溶接部保護装置の設置状態（図１のＡ部）を示す構成図。The block diagram which shows the installation state (A part of FIG. 1) of a reactor pressure vessel penetration part and a welding part protection apparatus. （Ａ）は本発明の第１の実施形態を示す溶接部保護装置の縦断面構造の説明図、（Ｂ）は図３（Ａ）のＡ−Ａ線に沿う平断面図。(A) is explanatory drawing of the longitudinal cross-section of the welding part protection apparatus which shows the 1st Embodiment of this invention, (B) is a plane sectional view which follows the AA line of FIG. 3 (A). （Ａ）は本発明の第２の実施形態を示す溶接部保護装置の縦断面構造の説明図、（Ｂ）は図４（Ａ）のＢ−Ｂ線に沿う平断面図。(A) is explanatory drawing of the longitudinal cross-section of the welding part protection apparatus which shows the 2nd Embodiment of this invention, (B) is a plane sectional view which follows the BB line of FIG. 4 (A). （Ａ）は本発明の第３の実施形態を示す溶接部保護装置の縦断面構造の説明図、（Ｂ）は図５（Ａ）のＣ−Ｃ線に沿う平断面図。(A) is explanatory drawing of the longitudinal cross-section of the welding part protection apparatus which shows the 3rd Embodiment of this invention, (B) is a plane sectional view which follows the CC line of FIG. 5 (A). （Ａ）は本発明の第４の実施形態を示す溶接部保護装置の片側縦断面構造の部分的な説明図、（Ｂ）は図６（Ａ）に示す状態から溶接部保護装置が変形した状態を示す部分的な説明図。(A) is partial explanatory drawing of the one-side longitudinal cross-section structure of the welding part protection apparatus which shows the 4th Embodiment of this invention, (B) has deformed the welding part protection apparatus from the state shown in FIG. 6 (A). Partial explanatory drawing which shows a state. （Ａ）は本発明の第５の実施形態を示す溶接部保護装置の片側縦断面構造の部分的な説明図、（Ｂ）は図７（Ａ）に示す状態から溶接部保護装置が変形した状態を示す部分的な説明図。(A) is partial explanatory drawing of the one-side longitudinal cross-section structure of the welding part protection apparatus which shows the 5th Embodiment of this invention, (B) has deformed the welding part protection apparatus from the state shown in FIG. 7 (A). Partial explanatory drawing which shows a state. （Ａ）は本発明の第６の実施形態を示す溶接部保護装置の片側縦断面構造の部分的な説明図、（Ｂ）は図８（Ａ）に示す状態から溶接部保護装置が変形した状態を示す部分的な説明図。(A) is partial explanatory drawing of the one-side longitudinal cross-sectional structure of the welding part protection apparatus which shows the 6th Embodiment of this invention, (B) has deformed the welding part protection apparatus from the state shown to FIG. 8 (A). Partial explanatory drawing which shows a state. 本発明の第７の実施形態を示す溶接部保護装置の片側縦断面構造の部分的な説明図。Partial explanatory drawing of the one-side longitudinal cross-sectional structure of the welding part protection apparatus which shows the 7th Embodiment of this invention. 本発明の第８の実施形態を示す溶接部保護装置の片側縦断面構造の部分的な説明図。Partial explanatory drawing of the one-side longitudinal cross-sectional structure of the welding part protection apparatus which shows the 8th Embodiment of this invention. 原子炉圧力容器の貫通部の共通部材の固定保持構造を示す部分的な縦断面図。The fragmentary longitudinal cross-section which shows the fixed holding structure of the common member of the penetration part of a reactor pressure vessel.

以下、本発明の実施形態について、添付図面を参照して説明する。   Embodiments of the present invention will be described below with reference to the accompanying drawings.

本発明の実施形態は水を冷却材とした水冷却型原子炉に適用される。水冷却型原子炉には沸騰水型原子炉や加圧水型原子炉の軽水型原子炉の他重水型原子炉がある。   The embodiment of the present invention is applied to a water-cooled nuclear reactor using water as a coolant. Water-cooled reactors include boiling water reactors, pressurized water reactors, light water reactors, and heavy water reactors.

図１は、水冷却型原子炉として沸騰水型原子炉の原子炉圧力容器１０の例を示すものである。原子炉圧力容器１０は、溶接構造の円筒型容器で構成され、内部に炉心１１を収容した炉心シュラウド１２がシュラウドサポート１３により支持される。炉心シュラウド１２を覆うシュラウドヘッド１４上には、スタンドパイプ１５を介して気水分離器１６が設けられ、この気水分離器１６上に蒸気乾燥器１７が設置される。   FIG. 1 shows an example of a reactor pressure vessel 10 of a boiling water reactor as a water cooled reactor. The reactor pressure vessel 10 is formed of a cylindrical vessel having a welded structure, and a core shroud 12 that houses a core 11 therein is supported by a shroud support 13. An air / water separator 16 is provided on the shroud head 14 covering the core shroud 12 via a stand pipe 15, and a steam dryer 17 is installed on the air / water separator 16.

また、原子炉圧力容器１０の圧力容器下鏡を構成する圧力容器下部ヘッド２０には、多数の制御棒駆動機構ハウジング（以下、ＣＲＤハウジング）２１が垂設され、図示しない制御棒駆動機構（ＣＲＤ）が設けられる。ＣＲＤハウジング２１上に図示しない炉心支持板との間で制御棒案内管２２が支持され、制御棒案内管２２は炉心１１内に、制御棒（図示せず）の出し入れを案内している。   In addition, a large number of control rod drive mechanism housings (hereinafter referred to as CRD housings) 21 are suspended from the pressure vessel lower head 20 constituting the pressure vessel lower mirror of the reactor pressure vessel 10, and a control rod drive mechanism (CRD not shown) is provided. ) Is provided. A control rod guide tube 22 is supported between the CRD housing 21 and a core support plate (not shown). The control rod guide tube 22 guides the control rod (not shown) into and out of the core 11.

なお、図１において、符号２３は主蒸気ノズルであり、符号２４は給水ノズルである。また、符号２５は再循環出口ノズルであり、符号２６は再循環入口ノズルである。   In addition, in FIG. 1, the code | symbol 23 is a main steam nozzle and the code | symbol 24 is a water supply nozzle. Reference numeral 25 denotes a recirculation outlet nozzle, and reference numeral 26 denotes a recirculation inlet nozzle.

ＣＲＤハウジング２１は、図２に示すように、圧力容器下部ヘッド２０の貫通部２８を通る部材（以下、貫通部材という。）２１を構成している。貫通部材２１は圧力容器下部ヘッド２０上で（サポートスリーブを構成する）スタブチューブ２９に溶接部３０で固定され、保持される。このように、貫通部材２１は原子炉圧力容器１０内部に突き出た位置で貫通部２８に拘束されて固定保持される。この実施形態は、圧力容器下部ヘッド（圧力容器下鏡）２０の貫通部２８を貫通部材２１が下方から挿入され、圧力容器下部ヘッド２０上で溶接部３０により固定支持される原子炉を対象としている。   As shown in FIG. 2, the CRD housing 21 constitutes a member (hereinafter referred to as a penetrating member) 21 that passes through the penetrating portion 28 of the pressure vessel lower head 20. The penetrating member 21 is fixed to the stub tube 29 (which constitutes a support sleeve) on the pressure vessel lower head 20 by a welding portion 30 and held. In this way, the penetrating member 21 is fixed and held by the penetrating portion 28 at a position protruding into the reactor pressure vessel 10. This embodiment is intended for a nuclear reactor in which a penetrating member 21 is inserted from below through a penetrating portion 28 of a pressure vessel lower head (pressure vessel lower mirror) 20 and fixedly supported by a weld 30 on the pressure vessel lower head 20. Yes.

ところで、貫通部材２１の溶接部３０は原子炉圧力容器１０内で炉心下部プレナム３１に露出して晒されるため、炉心溶融が万一生じて１０００℃を遥かに超える高温の炉心溶融物が圧力容器下部ヘッド２０上に溶け落ちると、炉心溶融物が堆積されるスタブチューブ２９や制御棒案内管２２の温度が非常高温となり、溶接部３０に溶融が生じる虞がある。溶接部３０が溶融すると、貫通部材２１が抜け落ち、落下することが懸念される。この原子炉圧力容器１０内の溶接部２５の溶融・破損が生じるのを防止するため、原子炉圧力容器１０内に溶接部保護装置３３が設けられる。   By the way, the welded portion 30 of the penetrating member 21 is exposed and exposed to the lower plenum 31 in the reactor pressure vessel 10, so that the core melt should occur and the high temperature core melt far exceeding 1000 ° C. If it melts onto the lower head 20, the temperature of the stub tube 29 and the control rod guide tube 22 on which the core melt is deposited becomes extremely high, and there is a possibility that the weld 30 is melted. When the welded portion 30 is melted, there is a concern that the penetrating member 21 falls off and falls. In order to prevent melting and breakage of the welded portion 25 in the reactor pressure vessel 10, a welded portion protection device 33 is provided in the reactor pressure vessel 10.

溶接部保護装置３３は、原子炉圧力容器貫通部２８の溶接部３０周囲に設置され、貫通部材２１を固定保持する溶接部３０を、トーラス状あるいはドーナツ状の金属カバー容器３５内に収容される断熱材３６で熱的に保護するものである。   The welded part protection device 33 is installed around the welded part 30 of the reactor pressure vessel penetrating part 28, and the welded part 30 that fixes and holds the penetrating member 21 is accommodated in a torus-shaped or donut-shaped metal cover container 35. This is thermally protected by the heat insulating material 36.

金属カバー容器３５は、例えば、ボックス状容器３５ａの開口部を蓋材３５ｂで覆って２分割可能に構成される。金属カバー容器３５の分割構造は他にも種々の割型が考えられる。金属カバー容器３５は、ステンレス鋼や炭素鋼等の炉内構造物に用いられる金属材料で構成され、プレス成形や絞り成形、削り出し成形などで型成形される。金属カバー容器３５は溶接部３０に接触する部分が無垢の材料で好適に構成される。   The metal cover container 35 is configured to be divided into two parts by covering the opening of the box-shaped container 35a with a lid member 35b, for example. Various other split types are possible for the divided structure of the metal cover container 35. The metal cover container 35 is made of a metal material used for an in-furnace structure such as stainless steel or carbon steel, and is molded by press molding, draw molding, cut-out molding, or the like. The metal cover container 35 is preferably composed of a solid material at a portion contacting the welded portion 30.

また、金属カバー容器３５内に収容される断熱材３６には、鉄酸化物、酸化アルミニウム（ＡｌＯ２）、酸化ジルコニウム（ＺｎＯ２）等で構成され、断熱材３６は断熱性能を良好にするため、繊維状金属材料が充填され、収容される。 The heat insulating material 36 accommodated in the metal cover container 35 is made of iron oxide, aluminum oxide (AlO 2 ), zirconium oxide (ZnO 2 ), etc., and the heat insulating material 36 has good heat insulating performance. And filled with a fibrous metal material.

溶接部保護装置３３は、原子炉圧力容器貫通部２８の溶接部３０周囲を覆うように設置され、貫通部材２１を固定保持する溶接部３０の周囲を、断熱材３６で熱的に保護している。万一の炉心溶融時、炉心溶融物が圧力容器下部ヘッド２０上に落下すると、落下した炉心溶融物は冷却水により冷却され、固化して体積されるが、冷却水が蒸発してドライアウト状態になると、崩壊熱により炉心溶融物の温度が上昇する。上昇した温度や圧力により、溶接部保護装置３３は機械的・物理的強度が不足し、溶接部３０が損傷を受ける虞がある。   The welded part protection device 33 is installed so as to cover the periphery of the welded part 30 of the reactor pressure vessel penetrating part 28, and thermally protects the periphery of the welded part 30 that fixes and holds the penetrating member 21 with the heat insulating material 36. Yes. In the unlikely event of melting of the core, if the core melt falls onto the pressure vessel lower head 20, the dropped core melt is cooled and solidified by cooling water, but the cooling water evaporates and is in a dry-out state. Then, the temperature of the core melt rises due to decay heat. Due to the increased temperature and pressure, the welded part protection device 33 is insufficient in mechanical and physical strength, and the welded part 30 may be damaged.

［第１の実施形態］
図３（Ａ）および（Ｂ）は、原子炉圧力容器の第１の実施形態を示すもので、その溶接部保護装置３３Ａを示す縦断面図および平断面図である。図１および図２と同じ構成には同一符号を付して重複説明を省略する。 [First Embodiment]
FIGS. 3A and 3B show a first embodiment of a reactor pressure vessel, and are a longitudinal sectional view and a plan sectional view showing a welded part protection device 33A. The same components as those in FIG. 1 and FIG.

原子炉圧力容器１０は、原子炉圧力容器１０内部に立設されたスタブチューブ２９頂部の溶接部３０でＣＲＤハウジングの貫通部材２１を固定保持しており、貫通部材２１を固定保持する溶接部３０の周囲を溶接部保護装置３３Ａが外周側から覆設される。溶接部保護装置３３Ａは溶接部３０を熱的に保護している。   In the reactor pressure vessel 10, the penetrating member 21 of the CRD housing is fixedly held by the welded portion 30 at the top of the stub tube 29 erected inside the reactor pressure vessel 10, and the welded portion 30 that fixes and holds the penetrating member 21. 33 A of welding part protection devices 33A are covered from the outer peripheral side. The welded part protection device 33A protects the welded part 30 thermally.

溶接部保護装置３３Ａは、図３（Ａ）および（Ｂ）に示すように、トーラス状あるいはドーナツ状の金属カバー容器３５内に断熱材３６が充填され、収容される一方、金属カバー容器３５内部に周方向に沿って等間隔に垂直（縦）リブ３７が放射状に配設されて補強構造に構成される。垂直リブ３７は、コバルトや鉄系金属材料、酸化ジルコニウム、アルミナ、タングステン等の剛性材料で板状補剛部材を構成している。垂直リブ３７のリブ内側およびリブ外側は金属カバー容器３５の内壁に固定され、金属カバー容器３５の物理的・機械的強度や剛性を高めている。   As shown in FIGS. 3 (A) and 3 (B), the welded part protection device 33A is filled with a heat insulating material 36 in a torus-shaped or donut-shaped metal cover container 35 and accommodated therein. In addition, vertical (vertical) ribs 37 are radially arranged at equal intervals along the circumferential direction to constitute a reinforcing structure. The vertical ribs 37 constitute a plate-shaped stiffening member made of a rigid material such as cobalt, an iron-based metal material, zirconium oxide, alumina, or tungsten. The rib inner side and the rib outer side of the vertical rib 37 are fixed to the inner wall of the metal cover container 35 to enhance the physical / mechanical strength and rigidity of the metal cover container 35.

溶接部保護装置３３Ａは、圧力容器下部ヘッド２０の突出位置で（貫通部材２１を固定保持する）溶接部３０への装着性や取付性を考慮して割型構造に構成される。溶接部保護装置３３Ａは、圧力容器下部ヘッド２０の突出位置で、貫通部材２１を固定保持する溶接部３０の周囲を断熱材３６で覆って保護することで、溶接部３０への熱伝達を効果的に防止している。圧力容器下部ヘッド２０の貫通部２８上の溶接部３０の周囲を断熱材３６と金属カバー容器３５で覆うだけでは溶接部保護装置３３Ａの機械的・物理的強度が劣り、不足する可能性がある。このため、溶接部保護装置３３Ａは、金属カバー容器３５内部に板状補剛部材の縦（垂直）リブ３７を放射状に配設することで、金属カバー容器３５の強度、剛性を向上させ、貫通部材２１を固定保持する溶接部３０の損傷・破損を防止するものである。   The welded part protection device 33A is configured in a split structure in consideration of the mounting property and the mounting property to the welded part 30 (the penetrating member 21 is fixedly held) at the protruding position of the pressure vessel lower head 20. The welded part protection device 33 </ b> A effectively protects the heat transfer to the welded part 30 by covering and protecting the periphery of the welded part 30 that fixes and holds the penetrating member 21 with the heat insulating material 36 at the protruding position of the pressure vessel lower head 20. Prevent it. Simply covering the periphery of the welded portion 30 on the penetrating portion 28 of the pressure vessel lower head 20 with the heat insulating material 36 and the metal cover container 35 may deteriorate the mechanical / physical strength of the welded portion protection device 33A and may be insufficient. . For this reason, the welded part protection device 33A improves the strength and rigidity of the metal cover container 35 by disposing the vertical (vertical) ribs 37 of the plate-shaped stiffening member radially inside the metal cover container 35, and penetrates it. This prevents damage and breakage of the welded portion 30 that fixes and holds the member 21.

［作用］
原子炉圧力容器１０の溶接部保護装置３３Ａの取付は、次のようにして行なわれる。 [Action]
The welded part protection device 33A for the reactor pressure vessel 10 is attached as follows.

原子炉の建設時や定検時等に、原子炉圧力容器１０は圧力容器下部ヘッド２０の各貫通部２８に立設されたスタブチューブ２９に貫通部材２１を挿入し、貫通部材２１を圧力容器下部ヘッド貫通部２８上で、周溶接して溶接部３０に固定保持される。   At the time of construction of the nuclear reactor or at the time of regular inspection, the reactor pressure vessel 10 inserts a penetrating member 21 into a stub tube 29 erected at each penetrating portion 28 of the pressure vessel lower head 20, and the penetrating member 21 is inserted into the pressure vessel. On the lower head penetrating portion 28, it is circumferentially welded and fixedly held to the welded portion 30.

貫通部材２１を溶接部３０に固定保持させた後、圧力容器下部ヘッド２０上の溶接部３０周囲を覆うように、溶接部保護装置３３Ａが装着され、取り付けられる。溶接部保護装置３３Ａは、圧力容器下部ヘッド２０の溶接部３０周囲を覆って設置される。   After fixing the penetrating member 21 to the welded portion 30, the welded portion protection device 33A is attached and attached so as to cover the periphery of the welded portion 30 on the pressure vessel lower head 20. The welded part protection device 33 </ b> A is installed to cover the periphery of the welded part 30 of the pressure vessel lower head 20.

溶接部保護装置３３Ａには、トーラス状あるいはドーナツ状金属カバー容器３５の内部に垂直リブ３７が放射状に配設され、かつ金属カバー容器３５内に断熱材３６が充填され、収容されている。   In the welded part protection device 33A, vertical ribs 37 are radially arranged inside a torus-shaped or donut-shaped metal cover container 35, and the metal cover container 35 is filled with a heat insulating material 36 and accommodated therein.

しかして、圧力容器下部ヘッド２０の突出位置で、溶接部３０により貫通部材２１を固定させ、保持した状態で、溶接部３０の周囲を覆うように溶接部保護装置３３Ａを外側あるいは上方から被せて装着し、設置される。溶接部保護装置３３Ａは各圧力容器下部ヘッド２０上の溶接部３０を順次覆うように設置していくことで、溶接部保護装置３３Ａの取付が完了し、原子炉圧力容器１０の貫通部２８上の溶接部３０の熱的保護構造が得られる。   Then, in the protruding position of the pressure vessel lower head 20, the penetration member 21 is fixed and held by the welded portion 30, and the welded portion protection device 33A is covered from the outside or the upper side so as to cover the periphery of the welded portion 30. Installed and installed. The welded part protection device 33A is installed so as to sequentially cover the welded parts 30 on the respective pressure vessel lower heads 20, so that the attachment of the welded part protective device 33A is completed, and the welded part protection device 33A Thus, a thermal protection structure for the welded portion 30 is obtained.

溶接部保護装置３３Ａを取り付けた後、制御棒案内管２２、図示しない制御棒、炉心１１、気水分離器１６や蒸気乾燥器１７等が原子炉圧力容器１０内で所要の手順で順次組み立てて構成され、原子炉圧力容器１０が構成されたり、あるいは検査後の原子炉圧力容器１０の組立が完了される。   After attaching the welded part protection device 33A, the control rod guide tube 22, the control rod (not shown), the core 11, the steam / water separator 16, the steam dryer 17, and the like are sequentially assembled in the reactor pressure vessel 10 in the required procedure. The reactor pressure vessel 10 is configured, or the assembly of the reactor pressure vessel 10 after the inspection is completed.

［第１の実施形態の効果］
第１の実施形態は、原子炉圧力容器１０底部の各貫通部材２１を圧力容器下部ヘッド２０上で固定保持する溶接部３０を、断熱材３６を備えた補強構造の溶接部保護装置３３Ａで周囲から覆って保護したので、溶接部３０の温度を融点以下に保持して、溶接部３０の溶融や損傷を防止することができる。 [Effect of the first embodiment]
In the first embodiment, the welded portion 30 that fixes and holds each penetrating member 21 at the bottom of the reactor pressure vessel 10 on the pressure vessel lower head 20 is surrounded by a welded portion protection device 33A having a reinforcing structure provided with a heat insulating material 36. Therefore, it is possible to prevent the welded portion 30 from being melted or damaged by keeping the temperature of the welded portion 30 below the melting point.

また、溶接部保護装置３３Ａは金属カバー容器３５内に、縦リブ３７を放射状に配置したので、金属カバー容器３５の強度・剛性を向上させることができ、通常運転時の冷却水や事故時の炉心溶融物の温度や圧力による損傷・破損を防ぐことができ、溶接部３０の保護を図ることができる。したがって、万一の事故時に炉心溶融が生じて、炉心溶融物が圧力容器下部ヘッド２０上に落下しても、溶接部３０の溶融や損傷を効果的に防止し、貫通部材２１が抜け落ちて落下するのを防ぐことができる。   Moreover, since the welded part protection device 33A radially arranges the vertical ribs 37 in the metal cover container 35, the strength and rigidity of the metal cover container 35 can be improved. Damage and breakage due to temperature and pressure of the core melt can be prevented, and the welded portion 30 can be protected. Therefore, even if the core melts in the event of an accident and the core melt falls on the pressure vessel lower head 20, it is possible to effectively prevent melting and damage of the welded portion 30, and the penetrating member 21 falls off and falls. Can be prevented.

［第２の実施形態］
次に、原子炉圧力容器の第２の実施形態を図４（Ａ）および（Ｂ）を参照して説明する。 [Second Embodiment]
Next, a second embodiment of the reactor pressure vessel will be described with reference to FIGS. 4 (A) and 4 (B).

第２の実施形態に係る原子炉圧力容器１０は、その溶接部保護装置３３Ｂの補強構造が第１の実施形態に示される原子炉圧力容器１０の溶接部保護装置３３Ａの補強構造と異なり、他の構成は異ならないので、同じ構成には同一符号を付し、重複する説明を省略ないしは簡略化する。   The reactor pressure vessel 10 according to the second embodiment differs from the reinforcement structure of the weld zone protection device 33A of the reactor pressure vessel 10 shown in the first embodiment in the reinforcement structure of the weld zone protection device 33B. Therefore, the same components are denoted by the same reference numerals, and redundant descriptions are omitted or simplified.

図４（Ａ）および（Ｂ）は、原子炉圧力容器１０の溶接部保護装置３３Ｂを示す縦断面図および平断面図である。   4A and 4B are a longitudinal sectional view and a plan sectional view showing the welded part protection device 33B of the reactor pressure vessel 10, respectively.

この溶接部保護装置３３Ｂは、原子炉圧力容器１０内の突出位置（スタブチューブ２９）で溶接部３０を周囲から覆って保護するものである。圧力容器下部ヘッド２０の突出位置（スタブチューブ２９）の溶接部３０で原子炉圧力容器１０の貫通部２８を貫く、貫通部材２１を固定保持し、貫通部材２１を固定する溶接部３０を周囲から溶接部保護装置３３Ｂで覆って熱的に保護するものである。   The welded part protection device 33B covers and protects the welded part 30 from the periphery at the protruding position (stub tube 29) in the reactor pressure vessel 10. The welded portion 30 that penetrates the penetration portion 28 of the reactor pressure vessel 10 at the welding portion 30 at the protruding position (stub tube 29) of the pressure vessel lower head 20 is fixed and held, and the welded portion 30 that fixes the penetration member 21 is surrounded from the periphery. It is covered and thermally protected by the welded part protection device 33B.

第２の実施形態に示された溶接部保護装置３３Ｂは、断熱材３６を備えたトーラス状あるいはドーナツ状金属カバー容器３５の内部にリング状あるいはワッシャ状の水平リブ３８を複数箇所で縦方向に間隔を置いて段状に配設した構成が、縦リブ３７を放射状に配設した第１の実施形態の溶接部保護装置３３Ａとは相違する。水平リブ３８は、金属カバー容器３５内に一段だけ水平方向に配設したものでもよい。水平リブ３８はコバルト、あるいは鉄系金属材料、酸化ジルコニウム、アルミナ、タングステン等の剛性材料で構成された板状補剛部材である。   The welded part protection device 33B shown in the second embodiment includes a ring-shaped or washer-shaped horizontal rib 38 in a vertical direction at a plurality of locations inside a torus-shaped or donut-shaped metal cover container 35 provided with a heat insulating material 36. The configuration in which the gaps are arranged stepwise is different from the welded part protection device 33A of the first embodiment in which the longitudinal ribs 37 are radially arranged. The horizontal ribs 38 may be arranged in the metal cover container 35 by one level in the horizontal direction. The horizontal rib 38 is a plate-shaped stiffening member made of a rigid material such as cobalt, an iron-based metal material, zirconium oxide, alumina, or tungsten.

第２の実施形態の原子炉圧力容器１０の溶接部保護装置３３Ｂにおいて、圧力容器下部ヘッド貫通部２８上の溶接部３０への溶接部保護装置３３Ｂの取付は、第１の実施形態に示された溶接部保護装置３３Ａの取付と、金属カバー容器３５の内部の水平リブ３８の配設構造が異なるのみで、他の取付態様は異ならないので、説明を省略する。   In the weld zone protection device 33B of the reactor pressure vessel 10 of the second embodiment, the attachment of the weld zone protection device 33B to the weld portion 30 on the pressure vessel lower head penetration 28 is shown in the first embodiment. Since only the attachment structure of the welded part protection device 33A and the arrangement structure of the horizontal ribs 38 inside the metal cover container 35 are different, and other attachment modes are not different, the description is omitted.

［第２の実施形態の効果］
原子炉圧力容器１０底部を貫通する貫通部材２１を圧力容器下部ヘッド２０の突出位置で固定保持する溶接部３０の周囲を、断熱材３６を備えた補強構造の溶接部保護装置３３Ｂで覆って保護することで、第１の実施形態と同様、万一の炉心溶融時にも、溶接部３０の温度を融点以下に保持して、溶接部３０の溶融や損傷を防止することができる。 [Effects of Second Embodiment]
The periphery of the welded portion 30 that fixes and holds the penetrating member 21 penetrating the bottom of the reactor pressure vessel 10 at the protruding position of the pressure vessel lower head 20 is covered and protected by a welded portion protection device 33B having a reinforcing structure provided with a heat insulating material 36. Thus, as in the first embodiment, even in the unlikely event of core melting, the temperature of the welded portion 30 can be maintained below the melting point, and melting or damage of the welded portion 30 can be prevented.

また、溶接部保護装置３３Ｂにおいても、補強構造に構成して金属カバー容器３５の強度、剛性を向上させることができ、第１の実施形態に示される溶接部保護装置３３Ａと同様の効果を奏することができ、溶接部３０の熱的保護を図ることができ、貫通部材２１が抜け落ちて落下するのを防止することができる。   Further, the welded part protection device 33B can also be configured as a reinforcing structure to improve the strength and rigidity of the metal cover container 35, and has the same effect as the welded part protection apparatus 33A shown in the first embodiment. Therefore, the thermal protection of the welded portion 30 can be achieved, and the penetrating member 21 can be prevented from falling off and falling.

［第３の実施形態］
図５（Ａ）および（Ｂ）は、原子炉圧力容器の第３の実施形態を示す縦断面図および平断面図である。 [Third Embodiment]
FIGS. 5A and 5B are a longitudinal sectional view and a plan sectional view showing a third embodiment of the reactor pressure vessel.

第３の実施形態に示された原子炉圧力容器１０の溶接部保護装置３３Ｃは、第１の実施形態に示された溶接部保護装置３３Ａの板状補剛部材に代り、金属カバー容器３５の内部にバー（棒）状補剛部材のリバー３９を配設した構成を採用したもので、他の構成は、第１の実施形態に示された原子炉圧力容器１０の溶接部保護装置３３Ａと異ならないので、同じ構成には同一符号を付して重複説明を省略する。   The welded part protection device 33C of the reactor pressure vessel 10 shown in the third embodiment is replaced with a plate-shaped stiffening member of the welded part protection device 33A shown in the first embodiment, and is replaced with a metal cover vessel 35. A configuration in which a bar (bar) stiffening member river 39 is disposed inside is employed, and the other configuration is the same as the welded part protection device 33A of the reactor pressure vessel 10 shown in the first embodiment. Since they are not different, the same components are denoted by the same reference numerals and redundant description is omitted.

第３の実施形態に示される原子炉圧力容器１０において、その溶接部保護装置３３Ｃは、原子炉圧力容器１０内部に貫通部２８から突き出した位置で、（貫通部材２１を固定支持する）溶接部３０を外周部から覆い保護するものである。溶接部保護装置３３Ｃは、第１の実施形態の溶接部保護装置３３Ａに用いられる縦リブ３７の板状補剛部材に代り、バー（棒）状補剛部材であるリバー３９を用いたものである。   In the reactor pressure vessel 10 shown in the third embodiment, the welded portion protection device 33C is a welded portion (fixingly supporting the penetration member 21) at a position protruding from the penetration portion 28 inside the reactor pressure vessel 10. 30 is covered and protected from the outer periphery. The welded part protection device 33C uses a bar 39 that is a bar-shaped stiffening member instead of the plate-like stiffening member of the vertical rib 37 used in the welded part protection apparatus 33A of the first embodiment. is there.

第３の実施形態において、原子炉圧力容器１０の溶接部保護装置３３Ｃは、断熱材３６を備えたトーラス状あるいはドーナツ状金属カバー容器３５の内部に周方向に沿ってバー状補剛部材のリバー３９を放射状に複数本配設したものである。リバー３９は第１の実施形態の縦リブ３７および第２の実施形態の水平リブ３８と同じ剛性材料で構成されて、水平方向に配設され、リバー３９両端が金属カバー容器３５の内壁に固定される。放射状のリバー３９は金属カバー容器３５内部で１段あるいは２段以上の多段構造に配設される。   In the third embodiment, the welded part protection device 33C of the reactor pressure vessel 10 includes a bar-shaped stiffening member river along the circumferential direction inside a torus-like or donut-like metal cover vessel 35 provided with a heat insulating material 36. A plurality of 39 are arranged radially. The river 39 is made of the same rigid material as the vertical ribs 37 of the first embodiment and the horizontal ribs 38 of the second embodiment, and is arranged in the horizontal direction, and both ends of the river 39 are fixed to the inner wall of the metal cover container 35. Is done. The radial river 39 is arranged inside the metal cover container 35 in a multistage structure having one or more stages.

第３の実施形態の溶接部保護装置３３Ｃは、圧力容器下部ヘッド２０の突出位置で溶接部３０の周囲を金属カバー容器３５および断熱材３６で覆って保護することで、圧力容器下部ヘッド２０上で貫通部材２１を保持する溶接部３０への熱の伝達を防ぐことができる。また、溶接部保護装置３３Ｃは金属カバー容器３５の内部にバー状補剛部材の複数本のリバー３９を放射状に配設することで、補強構造に構成でき、金属カバー容器３５の強度や剛性を向上させることができる。   The welded part protection device 33C of the third embodiment covers and protects the periphery of the welded part 30 with the metal cover container 35 and the heat insulating material 36 at the protruding position of the pressure vessel lower head 20, thereby protecting the pressure vessel lower head 20. Therefore, it is possible to prevent heat from being transferred to the welded portion 30 that holds the penetrating member 21. Further, the welded part protection device 33C can be configured as a reinforcing structure by radially arranging a plurality of bar-shaped stiffening members 39 inside the metal cover container 35, and the strength and rigidity of the metal cover container 35 can be increased. Can be improved.

第３の実施形態において、原子炉圧力容器１０の溶接部保護装置３３Ｃの取付は、第１の実施形態の溶接部保護装置３３Ａの取付と、金属カバー容器３５内のリバー３９の配設を除いて異ならないので、第１の実施形態を参照して詳細な説明を省略する。   In the third embodiment, the welding part protection device 33C of the reactor pressure vessel 10 is attached except for the attachment of the welding part protection device 33A of the first embodiment and the arrangement of the river 39 in the metal cover container 35. Therefore, detailed description will be omitted with reference to the first embodiment.

［第３の実施形態の効果］
原子炉圧力容器１０底部を貫通する貫通部材２１を圧力容器下部ヘッド２０の突出位置で固定保持する溶接部３０の周囲を、断熱材３６を備えた溶接部保護装置３３Ｃで覆って保護することで、第１の実施形態と同様、万一の炉心溶融時にも、溶接部３０の温度を融点以下に保持して、溶接部３０の溶融や損傷を防止することができる。 [Effect of the third embodiment]
By covering and protecting the periphery of the welded portion 30 that fixes and holds the penetrating member 21 penetrating the bottom of the reactor pressure vessel 10 at the protruding position of the pressure vessel lower head 20 with a welded portion protection device 33C provided with a heat insulating material As in the first embodiment, even in the unlikely event of melting of the core, the temperature of the welded portion 30 can be kept below the melting point to prevent the welded portion 30 from being melted or damaged.

また、溶接部保護装置３３Ｃにおいても、複数本のバー状補剛部材のリバー３９を放射状に配設して金属カバー容器３５の強度、剛性を向上させることができ、第１の実施形態に示された溶接部保護装置３３Ａと同様の効果を奏することができ、溶接部３０の保護を図ることができる。   Also in the welded part protection device 33C, a plurality of bar-shaped stiffening member rivers 39 can be arranged radially to improve the strength and rigidity of the metal cover container 35, as shown in the first embodiment. The effect similar to the welded part protection device 33A can be obtained, and the welded part 30 can be protected.

［第４の実施形態］
次に、原子炉圧力容器の第４の実施形態を図６（Ａ）および（Ｂ）を参照して説明する。 [Fourth Embodiment]
Next, a fourth embodiment of the reactor pressure vessel will be described with reference to FIGS. 6 (A) and (B).

図６（Ａ）および（Ｂ）は、原子炉圧力容器１０の溶接部保護装置３３Ｄの片側縦断面構造を部分的に示す概略図である。この溶接部保護装置３３Ｄを説明するに当り、第１の実施形態ないし第３の実施形態に示された原子炉圧力容器１０の溶接部保護装置３３Ａ，３３Ｂ，３３Ｃと同じ構成には同一符号を付して重複する説明を省略する。   6 (A) and 6 (B) are schematic views partially showing a one-side longitudinal sectional structure of a welded part protection device 33D of the reactor pressure vessel 10. FIG. In the description of the welded part protection device 33D, the same reference numerals are given to the same components as the welded part protective devices 33A, 33B, 33C of the reactor pressure vessel 10 shown in the first to third embodiments. A duplicate description will be omitted.

図６（Ａ）に示される原子炉圧力容器の溶接部保護装置３３Ｄは、圧力容器下鏡の圧力容器下部ヘッド２０の突出位置上に位置する溶接部３０の周囲を覆い保護するものである。圧力容器下部ヘッド２０上突出位置の溶接部３０（図３（Ａ），図４（Ａ），図５（Ａ）参照）は、原子炉圧力容器１０の底部を貫通する貫通部材２１を固定保持するもので、この貫通部材２１を固定保持する溶接部３０の周囲を覆うように溶接部保護装置３３Ｄが設けられ、装着される。   The reactor pressure vessel welded part protection device 33D shown in FIG. 6A covers and protects the periphery of the welded part 30 located on the protruding position of the pressure vessel lower head 20 of the pressure vessel lower mirror. A welding portion 30 (see FIGS. 3A, 4A, and 5A) at a position protruding above the pressure vessel lower head 20 fixes and holds the penetrating member 21 that penetrates the bottom of the reactor pressure vessel 10. Therefore, a welded part protection device 33D is provided and attached so as to cover the periphery of the welded part 30 that fixes and holds the penetrating member 21.

溶接部保護装置３３Ｄは、第１の実施形態ないし第３の実施形態に示される金属カバー容器３５と同様、トーラス状あるいはドーナツ状金属カバー容器３５内に断熱材３６が収容される。金属カバー容器３５の内部には板状補剛部材であるリブ４０が水平方向に配設される。リブ４０に代えてバー（棒）状補剛部材のリバー３９であってもよい。リブ４０あるいはリバー３９の中間部４１が途中で凹凸結合され、弱化領域が形成されて嵌め合される。   As with the metal cover container 35 shown in the first to third embodiments, the welded part protection device 33D has a heat insulating material 36 accommodated in a torus-shaped or donut-shaped metal cover container 35. Inside the metal cover container 35, ribs 40, which are plate-shaped stiffening members, are disposed in the horizontal direction. Instead of the rib 40, a bar 39 of a bar-shaped stiffening member may be used. The rib 40 or the intermediate portion 41 of the river 39 is joined in the middle to form a weakened region, and is fitted.

第４の実施形態に示された原子炉圧力容器１０の溶接部保護装置３３Ｄでは、トーラス状あるいはドーナツ状金属カバー容器３５内に配置されるリブ４０あるいはリバーは、原子炉の通常運転時の水圧では補剛部材として機能し、リブ４０あるいはリバーが変形したり、凹凸結合が外れるのを防止することができる。リブ４０あるいはリバーには酸化ジルコニウムやアルミナ等の材料が用いられる。   In the welded part protection device 33D of the reactor pressure vessel 10 shown in the fourth embodiment, the rib 40 or the river disposed in the torus-like or donut-like metal cover vessel 35 has a water pressure during normal operation of the reactor. Then, it functions as a stiffening member, and it is possible to prevent the rib 40 or the river from being deformed or the concavo-convex bond from being released. A material such as zirconium oxide or alumina is used for the rib 40 or the river.

炉心溶融が生じる事故時の圧力容器下部ヘッド２０の変形挙動を熱流動解析で評価した解析結果表示例によると、炉心溶融物が堆積している圧力容器下部ヘッド２０貫通部近傍の温度分布では、スタブチューブ２９や制御棒案内管２２の温度が１２００℃程度の高温となっている例が紹介されている［日本原子力学会［２０１４年春の年会］２０１４年３月２６日〜２８日；Ｎ４８、事故時の圧力容器下部ヘッドの破損挙動評価に関する検討、（３）下部ヘッドの破損評価解析（その１）、原子力機構 加治芳行氏他５名 参照］。   According to the analysis result display example in which the deformation behavior of the pressure vessel lower head 20 at the time of the accident in which the core melts is evaluated is evaluated by thermal flow analysis, the temperature distribution near the penetration portion of the pressure vessel lower head 20 where the core melt is deposited is An example in which the temperature of the stub tube 29 and the control rod guide tube 22 is as high as about 1200 ° C. has been introduced [Japan Atomic Energy Society [2014 Spring Annual Meeting] March 26-28, 2014; N48, Examination of damage behavior evaluation of the pressure vessel lower head at the time of the accident, (3) Analysis of damage evaluation of the lower head (Part 1), see JAEA Yoshiyuki Kaji et al.

炉心溶融が生じる万一の事故時には、圧力容器下部ヘッド２０上に落下して体積される高温の炉心溶融物の温度・圧力に抗し切れず、溶接部保護装置３３Ｄの金属カバー容器３５が図６（Ｂ）に示すように変形し、損傷を受けることが予想される。   In the event of an accident in which core melting occurs, the metal cover container 35 of the welded part protection device 33D is not able to withstand the temperature and pressure of the hot core melt that falls on the pressure vessel lower head 20 and is volumed. As shown in FIG. 6 (B), it is expected to be deformed and damaged.

第４の実施形態に示された溶接部保護装置３３Ｄは、金属カバー容器３５の内部にリブ４０あるいはリバーが配設され、事故時に炉心溶融物の温度や圧力を受けて金属カバー容器３５が変形すると、図６（Ｂ）に示すように金属カバー容器３５内部のリブ４０あるいはリバーの凹凸結合が外れる。   In the welded part protection device 33D shown in the fourth embodiment, a rib 40 or a river is disposed inside the metal cover container 35, and the metal cover container 35 is deformed by receiving the temperature or pressure of the core melt at the time of an accident. Then, as shown in FIG. 6 (B), the concave-convex bond between the rib 40 or the river inside the metal cover container 35 is released.

金属カバー容器３５の内部に配設されたリブ４０あるいはリバーの凹凸結合が外れると、金属カバー容器３５の外部から内部に至る熱伝達経路が遮断され、断熱材３６による熱断熱機能を向上させることができる。溶接部保護装置３３Ｄは、リブ４０あるいはリバーによる外部から内部への熱伝達経路が遮断されることで、溶接部３０の温度を融点以下に保つことができる。溶接部３０の溶融・損傷を防ぎ、溶接部３０の溶融による貫通部材２１の落下を防止することができる。   When the ribs 40 or the ribs disposed inside the metal cover container 35 are disconnected, the heat transfer path from the outside to the inside of the metal cover container 35 is blocked, and the heat insulation function by the heat insulating material 36 is improved. Can do. The welded part protection device 33D can keep the temperature of the welded part 30 below the melting point by blocking the heat transfer path from the outside to the inside by the rib 40 or the river. It is possible to prevent melting and damage of the welded portion 30 and to prevent the penetrating member 21 from falling due to melting of the welded portion 30.

したがって、炉心溶融が生じる事故時にも、溶接部保護装置３３Ｄは、高温の炉心溶融物による溶接部３０の溶融、変形、損傷を防止することができ、貫通部材２１を固定・保持する溶接部３０を熱的に保護し、健全性を維持することができる。   Therefore, the welded part protection device 33D can prevent the welded part 30 from being melted, deformed, or damaged by the high-temperature core melt even in the event of an occurrence of core melting, and the welded part 30 that fixes and holds the penetrating member 21. Can be thermally protected and maintain soundness.

［第４の実施形態の効果］
第４の実施形態に係る原子炉圧力容器１０の溶接部保護装置３３Ｄにおいては、原子炉の通常運転時の冷却水の水圧では、金属カバー容器３５の変形を防止でき、金属カバー容器３５内部のリブ４０あるいはリバーは補剛部材として機能し、溶接部３０の損傷を防止することができる。 [Effect of the fourth embodiment]
In the welded part protection apparatus 33D of the reactor pressure vessel 10 according to the fourth embodiment, the water pressure of the cooling water during normal operation of the reactor can prevent the metal cover vessel 35 from being deformed, and the inside of the metal cover vessel 35 can be prevented. The rib 40 or the river functions as a stiffening member and can prevent the welded portion 30 from being damaged.

また、炉心溶融が生じる万一の事故時には、高温の炉心溶融物の温度圧力により溶接部保護装置３３Ｄの変形や損傷が生じても、金属カバー容器３５の変形とリブ４０あるいはリバーの凹凸結合の外れとを許容することで、金属カバー容器３５の外部から内部への熱伝達経路を遮断することができ、溶接部３０のか温度を融点以下に保つことで、溶接部３０の損傷を防止できる。したがって、溶接部３０の溶融・損傷を防ぎ、貫通部材２１の落下を防止でき、溶接部３０を保護することができる。   In the unlikely event of a core melting, even if the welded part protection device 33D is deformed or damaged by the temperature pressure of the hot core melt, the deformation of the metal cover container 35 and the uneven coupling of the rib 40 or the river By allowing the disengagement, the heat transfer path from the outside to the inside of the metal cover container 35 can be blocked, and by keeping the temperature of the welded portion 30 below the melting point, the welded portion 30 can be prevented from being damaged. Therefore, melting / damage of the welded portion 30 can be prevented, the penetrating member 21 can be prevented from falling, and the welded portion 30 can be protected.

［第５の実施形態］
次に、原子炉圧力容器の第５の実施形態を図７（Ａ）および（Ｂ）を参照して説明する。 [Fifth Embodiment]
Next, a fifth embodiment of the reactor pressure vessel will be described with reference to FIGS. 7 (A) and 7 (B).

図７（Ａ）および（Ｂ）は、原子炉圧力容器１０の溶接部保護装置３３Ｅの片側縦断面構造を部分的に示す概略図である。図６（Ａ）および（Ｂ）に示された第４の実施形態と同じ構成には、同一符号を付して重複説明を省略する。   FIGS. 7A and 7B are schematic views partially showing a one-side longitudinal cross-sectional structure of the welded part protection device 33E of the reactor pressure vessel 10. FIG. The same components as those in the fourth embodiment shown in FIGS. 6A and 6B are denoted by the same reference numerals, and redundant description is omitted.

図７（Ａ）に示される原子炉圧力容器の溶接部保護装置３３Ｅは、図３（Ａ），図４（Ａ）および図５（Ａ）に示すように、圧力容器下鏡の圧力容器下部ヘッド２０の突出位置（スタブチューブ２９）上部に位置する溶接部３０の周囲を覆い保護するものである。圧力容器下部ヘッド２０突出位置の溶接部３０は、原子炉圧力容器１０底部を貫通する貫通部材２１を固定保持するものである。溶接部保護装置３３Ｅは、貫通部材２１を固定保持する溶接部３０の周囲を覆って装着され、設けられる。   As shown in FIGS. 3 (A), 4 (A) and 5 (A), the reactor pressure vessel weld zone protection device 33E shown in FIG. The periphery of the welded portion 30 located above the protruding position (stub tube 29) of the head 20 is covered and protected. The welded portion 30 at the protruding position of the pressure vessel lower head 20 fixes and holds the penetrating member 21 that penetrates the bottom of the reactor pressure vessel 10. The welded part protection device 33E is mounted and provided so as to cover the periphery of the welded part 30 that fixes and holds the penetrating member 21.

第５の実施形態の原子炉圧力容器の溶接部保護装置３３Ｅは、トーラス状あるいはドーナツ金属カバー容器３５内に断熱材３６が収容される一方、金属カバー容器３５の内部に板状補剛部材あるいはバー状補剛部材のリブ４３あるいはリバーが配設される。リブ４３あるいはリバーは金属カバー容器３５外周側内壁および内周側内壁にそれぞれ固定される。両内壁に固定されたリブ４３あるいはリバーは、中間部４４が一部低融点金属あるいは樹脂材で構成される。低融点金属には、リブ４３あるいはリバーにより融点の低い金属材料、例えば銅（Ｃｕ）、銀（Ａｇ）、亜鉛（Ｚｎ）等で構成され、樹脂材にはプラスチックがある。低融点金属や樹脂材は、原子炉の通常運転時の冷却材温度では溶融することなく固定状態に保たれる。   In the reactor pressure vessel welded part protection device 33E of the fifth embodiment, a heat insulating material 36 is accommodated in a torus-shaped or donut metal cover container 35, while a plate-shaped stiffening member or Ribs 43 or rivers of bar-shaped stiffening members are provided. The ribs 43 or the rivers are respectively fixed to the outer peripheral side inner wall and the inner peripheral side inner wall of the metal cover container 35. The ribs 43 or the rivers fixed to the inner walls are partially made of a low melting point metal or a resin material. The low melting point metal is composed of a metal material having a low melting point by ribs 43 or a river, such as copper (Cu), silver (Ag), zinc (Zn), etc., and the resin material is plastic. The low melting point metal or resin material is kept in a fixed state without melting at the coolant temperature during normal operation of the nuclear reactor.

第５の実施形態の原子炉圧力容器の溶接部保護装置３３Ｅでは、トーラス状あるいはドーナツ状の金属カバー容器３５内部に配設されたリブ４３あるいはリバーは、原子炉の通常運転時の水圧では、補剛部材として機能し、低融点金属や樹脂材が溶融して変質するのを防止することができる。   In the reactor pressure vessel welded part protection apparatus 33E according to the fifth embodiment, the rib 43 or the river disposed in the torus-shaped or donut-shaped metal cover vessel 35 has a water pressure during normal operation of the reactor. It functions as a stiffening member and can prevent the low melting point metal or resin material from being melted and altered.

炉心溶融が生じる万一の事故時には、圧力容器下部ヘッド２０上に落下して体積される高温の炉心溶融物の温度・圧力に抗し切れず、溶接部保護装置３３Ｅの金属カバー容器３５が変形し、損傷を受けることが予想される。   In the unlikely event that the core melts, the metal cover container 35 of the welded part protection device 33E is deformed without being able to resist the temperature and pressure of the hot core melt falling on the pressure vessel lower head 20 and volume. And is expected to be damaged.

第５の実施形態に示された溶接部保護装置３３Ｅは、金属カバー容器３５の内部に配設されたリブ４３あるいはリバーの一部が低融点金属あるいは樹脂材で構成されておれ、万一の炉心溶融時に炉心溶融物が落下して、温度・圧力を受けると、金属カバー容器３５内部にリブ４３あるいはリバーの低融点金属あるいは樹脂材の部分が溶融したり、変質する。この溶接部保護装置３３Ｅは、リブ４３あるいはリバーの低融点金属あるいは樹脂材で構成された部分が溶融あるいは変質することを利用し、外部から内部への熱伝達経路を遮断し、溶接部３０の温度を融点以下に保って溶融を防ぎ、溶接部３０を保護することができる。したがって、溶接部３０の溶融・損傷を防止し、貫通部材２１の落下を防ぐことができる。   In the welded part protection device 33E shown in the fifth embodiment, a part of the rib 43 or the river disposed inside the metal cover container 35 is made of a low melting point metal or a resin material. When the core melt falls during the melting of the core and is subjected to temperature and pressure, the rib 43 or the low melting point metal or resin material portion of the river is melted or altered in the metal cover container 35. This welded part protection device 33E utilizes the fact that the rib 43 or the portion of the river made of a low melting point metal or resin material is melted or altered, interrupts the heat transfer path from the outside to the inside, and The temperature can be kept below the melting point to prevent melting and protect the welded portion 30. Therefore, melting / damage of the welded portion 30 can be prevented, and the penetrating member 21 can be prevented from falling.

［第５の実施形態の効果］
第５の実施形態に係る原子炉圧力容器の溶接部保護装置３３Ｅにおいては、原子炉の通常運転時には第４の実施形態で説明した溶接部保護装置３３Ｄと同様の効果を奏することができる。 [Effect of Fifth Embodiment]
In the reactor pressure vessel welded part protecting apparatus 33E according to the fifth embodiment, the same effects as the welded part protecting apparatus 33D described in the fourth embodiment can be obtained during normal operation of the reactor.

また、炉心溶融が生じる万一の事故時には、高温の炉心溶融物の温度・圧力により、溶接部保護装置３３Ｅにおいて、金属カバー容器３５内部に配設されたリブ４３あるいはリバーの低融点金属あるいは樹脂材で構成された部分が溶融あるいは変質することで、外部から内部への熱伝達経路を遮断することができ、溶接部３０の温度を融点以下に保って保護し、貫通部材２１の落下を防ぐことができる。   In the unlikely event that the core melts, the low temperature metal or resin of the rib 43 or the river disposed in the metal cover container 35 in the welded part protection device 33E due to the temperature and pressure of the hot core melt. By melting or altering the portion made of the material, the heat transfer path from the outside to the inside can be cut off, the temperature of the welded portion 30 is kept below the melting point, and the penetration member 21 is prevented from falling. be able to.

［第６の実施形態］
次に、原子炉圧力容器の第６の実施形態を図８（Ａ）および（Ｂ）を参照して説明する。 [Sixth Embodiment]
Next, a sixth embodiment of the reactor pressure vessel will be described with reference to FIGS. 8 (A) and 8 (B).

図８（Ａ）および（Ｂ）は、原子炉圧力容器の溶接部保護装置３３Ｆの片側縦断面構造を部分的に示す概略図である。図６（Ａ）および（Ｂ）に示された第４の実施形態と同じ構成には、同一符号を付して重複説明を省略する。   FIGS. 8A and 8B are schematic views partially showing a one-side longitudinal cross-sectional structure of a welded part protection device 33F of a reactor pressure vessel. The same components as those in the fourth embodiment shown in FIGS. 6A and 6B are denoted by the same reference numerals, and redundant description is omitted.

図８（Ａ）に示される原子炉圧力容器の溶接部保護装置３３Ｆは、圧力容器下鏡の圧力容器下部ヘッド２０の突出位置（スタブチューブ２９）上の溶接部３０の周囲を覆って保護するものである。圧力容器下部ヘッド２０突出位置上の溶接部３０は、原子炉圧力容器１０底部を貫通する貫通部材２１を固定保持するもので、この貫通部材２１を固定保持する溶接部３０の周囲を覆うように溶接部保護装置３３Ｆが設けられる。   The reactor pressure vessel welded portion protection device 33F shown in FIG. 8A covers and protects the periphery of the welded portion 30 on the protruding position (stub tube 29) of the pressure vessel lower head 20 of the pressure vessel lower mirror. Is. The welded portion 30 on the protruding position of the pressure vessel lower head 20 fixes and holds the penetrating member 21 that penetrates the bottom of the reactor pressure vessel 10, and covers the periphery of the welded portion 30 that fixes and holds the penetrating member 21. A welded part protection device 33F is provided.

溶接部保護装置３３Ｆは、トーラス状あるいはドーナツ状金属カバー容器３５内に断熱材３６が収容される。金属カバー容器３５の内部には板状補剛部材のリブ４５あるいはバー（棒）状補剛部材のリバーが水平方向に配設される。リブ４５あるいはリバーの両端部が金属カバー容器３５の内壁（外周側内壁および内周側内壁）に固定される。リブ４５あるいはリバーは中間部４６が途中で凹凸結合され、弱化領域が形成されて嵌め合される。リブ４５あるいはリバーの周囲には遮熱コーティング４８が施される。   In the welded part protection device 33 </ b> F, a heat insulating material 36 is accommodated in a torus-shaped or donut-shaped metal cover container 35. Inside the metal cover container 35, ribs 45 of plate-shaped stiffening members or rivers of bar-shaped stiffening members are arranged in the horizontal direction. Both ends of the rib 45 or the river are fixed to the inner wall (the outer peripheral side inner wall and the inner peripheral side inner wall) of the metal cover container 35. The ribs 45 or the rivers are engaged with each other by forming an uneven portion in the middle of the intermediate portion 46 to form a weakened region. A thermal barrier coating 48 is applied around the rib 45 or the river.

第６の実施形態に示された原子炉圧力容器１０の溶接部保護装置３３Ｆでは、トーラス状あるいはドーナツ状金属カバー容器３５内に配設されるリブ４５あるいはリバーは、原子炉の通常運転時の水圧では補剛部材として機能し、リブ４５あるいはリバーが変形したり、弱化領域の凹凸結合が外れるのを防止することができる。リブ４５やリバーには酸化ジルコニウムやアルミナ等の材料が用いられる。   In the welded part protection device 33F of the reactor pressure vessel 10 shown in the sixth embodiment, the rib 45 or the river disposed in the torus-like or donut-like metal cover vessel 35 is not provided during normal operation of the reactor. Under water pressure, it functions as a stiffening member, and it is possible to prevent the rib 45 or the river from being deformed and the uneven coupling in the weakened region from being released. A material such as zirconium oxide or alumina is used for the rib 45 and the river.

炉心溶融が生じる万一の事故時には、圧力容器下部ヘッド２０上に落下して体積される高温の炉心溶融物の温度・圧力に抗し切れず、溶接部保護装置３３Ｆの金属カバー容器３５が変形し、損傷を受けることが予想される。   In the unlikely event of a core melting, the metal cover container 35 of the welded part protection device 33F is deformed without being able to resist the temperature and pressure of the high temperature core melt falling on the pressure vessel lower head 20 and volume. And is expected to be damaged.

第６の実施形態に示された溶接部保護装置３３Ｆは、金属カバー容器３５の内部にリブ４５あるいはリバーが配設され、事故時に炉心溶融物の温度や圧力を受けて金属カバー容器３５が変形すると、図８（Ｂ）に示すように金属カバー容器３５内部のリブ４５あるいはリバーの中間部４６の凹凸結合が外れる。   In the welded part protection device 33F shown in the sixth embodiment, a rib 45 or a river is disposed inside the metal cover container 35, and the metal cover container 35 is deformed by receiving the temperature or pressure of the core melt at the time of an accident. Then, as shown in FIG. 8 (B), the concave-convex coupling of the rib 45 inside the metal cover container 35 or the intermediate portion 46 of the river is released.

金属カバー容器３５の内部に配設されたリブ４５あるいはリバーの凹凸結合が外れると、金属カバー容器３５の外部から内部に至る熱伝達経路が遮断され、遮熱コーティングや断熱材３６の作用で熱断熱機能を向上させることができる。溶接部保護装置３３Ｆは、リブ４５あるいはリバーによる外部から内部への熱伝達経路が遮断されることで、溶接部３０の温度を融点以下に保つことができる。このため、溶接部３０の溶融・損傷を防ぎ、溶接部３０の溶融による貫通部材２１の落下を防止することができる。   When the ribs 45 or the ribs disposed on the inside of the metal cover container 35 are disconnected, the heat transfer path from the outside to the inside of the metal cover container 35 is interrupted, and heat is applied by the action of the thermal barrier coating or the heat insulating material 36. The heat insulation function can be improved. The welded part protection device 33F can keep the temperature of the welded part 30 below the melting point by blocking the heat transfer path from the outside to the inside by the rib 45 or the river. For this reason, melting / damage of the welded portion 30 can be prevented, and dropping of the penetrating member 21 due to melting of the welded portion 30 can be prevented.

したがって、炉心溶融が生じる事故時にも、溶接部保護装置３３Ｆは、高温の炉心溶融物による溶接部３０の溶融、変形、損傷を防止することができ、貫通部材２１を固定・保持する溶接部３０を熱的に保護し、健全性を維持することができる。   Therefore, the welded part protection device 33F can prevent the welded part 30 from being melted, deformed, or damaged by the high-temperature core melt even in an accident in which core melting occurs, and the welded part 30 that fixes and holds the penetrating member 21. Can be thermally protected and maintain soundness.

［第６の実施形態の効果］
第６の実施形態に係る原子炉圧力容器の溶接部保護装置３３Ｆにおいては、原子炉の通常運転時や炉心溶融が生じる事故時には、第４の実施形態で説明した溶接部保護装置３３Ｄと同様の効果を奏する他、溶接部保護装置３３Ｆの金属カバー容器３５内部に配設されるリブ４５あるいはリバー同士が再接触した場合でも、遮熱コーティング４８によって再び熱伝達経路とすることを防ぐことができる。 [Effect of the sixth embodiment]
In the reactor pressure vessel welded part protection apparatus 33F according to the sixth embodiment, the same as the welded part protection apparatus 33D described in the fourth embodiment at the time of normal operation of the reactor or an accident in which core melting occurs. In addition to the effects, even when the ribs 45 or the rivers disposed inside the metal cover container 35 of the welded part protection device 33F are brought into contact with each other again, the heat shielding coating 48 can prevent the heat transfer path from being used again. .

［その他の実施形態］
本発明の実施形態に示された原子炉圧力容器の溶接部保護装置では、圧力容器下部ヘッド貫通部上の溶接部保護装置において、金属カバー容器の内部に補剛部材である金属製のリブやリバーを配設した補強構造の例を示したが、図９の第７の実施形態で示すように、溶接部保護装置３３Ｇは、金属カバー容器３５内部に配設されるリブあるいはリバー５０全体をセラミックスあるいは樹脂材で構成してもよい。この場合、セラミックスあるいは樹脂材製のリブやリバー５０は金属カバー容器３５の内壁から突出する係止用突起５１で保持され、固定されるように構成される。 [Other Embodiments]
In the reactor pressure vessel welded part protecting apparatus shown in the embodiment of the present invention, in the welded part protecting apparatus on the pressure vessel lower head penetration part, a metal rib or stiffening member is provided inside the metal cover container. Although the example of the reinforcing structure in which the river is disposed has been shown, as shown in the seventh embodiment of FIG. 9, the welded part protection device 33G has the rib disposed inside the metal cover container 35 or the entire river 50. You may comprise with ceramics or a resin material. In this case, the rib or river 50 made of ceramics or resin material is configured to be held and fixed by the locking protrusion 51 protruding from the inner wall of the metal cover container 35.

また、溶接部保護装置３３Ｈは、図１０の第８の実施形態に示すように、セラミックス５２をステンレス鋼製カバー５３で被覆して補剛部材のリブやレバー５４を構成し、このリブやリバー５４を金属カバー容器３５の内壁に溶接にて固定させる補強構造としてもよい。   Further, as shown in the eighth embodiment of FIG. 10, the welded part protection device 33H comprises a rib 52 and a lever 54 of a stiffening member by covering the ceramics 52 with a stainless steel cover 53, and this rib or river It is good also as a reinforcement structure which fixes 54 to the inner wall of the metal cover container 35 by welding.

いずれにしても、本発明の実施形態は、原子炉（圧力）容器の底部貫通部に貫通部材が挿入されて貫通し、原子炉（圧力）容器の貫通部上の溶接部で貫通部材を固定支持する溶接部を保護する補強構造の溶接部保護装置が設けられる。   In any case, in the embodiment of the present invention, the penetrating member is inserted into the bottom penetrating portion of the reactor (pressure) vessel and penetrates, and the penetrating member is fixed by the weld on the penetrating portion of the reactor (pressure) vessel. A welded part protection device having a reinforcing structure for protecting the supporting welded part is provided.

以上、本発明のいくつかの実施形態を説明したが、これらの実施形態は、例として提示したものであり、発明の範囲を限定することは意図していない。これら新規な実施形態は、その他の様々な形態で実施されることが可能であり、発明の要旨を逸脱しない範囲で種々の省略、置き換え、変更を行なうことができる。これらの実施形態やその変形は、発明の範囲や要旨に含まれるとともに、特許請求の範囲に記載された発明とその均等の範囲に含まれる。   As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

１０…原子炉圧力容器、１１…炉心、１２…炉心シュラウド、１３…シュラウドサポート、１４…シュラウドヘッド、１５…スタンドパイプ、１６…気水分離器、１７…蒸気乾燥器、２０…圧力容器下部ヘッド（圧力容器下鏡）、２１…貫通部材（制御棒駆動機構（ＣＲＤ）ハウジング）、２２…制御棒案内管、２３…主蒸気ノズル、２４…給水ノズル、２５…再循環出口ノズル、２６…再循環入口ノズル、２８…貫通部、２９…スタブチューブ（サポートチューブ）、３０…溶接部、３１…炉心下部プレナム、３３，３３Ａ〜３３Ｈ…溶接部保護装置、３５…金属カバー容器、３６…断熱材、３７…垂直リブ（板状補剛部材）、３８…水平リブ（板状補剛部材）、３９…リバー（棒状補剛部材）、４０，４３，４５…リブあるいはリバー（補剛部材）、４１，４６…中間部（凹凸結合部）、４４…低融点金属または樹脂材、４８…遮断コーティング、５０，５４…リブあるいはリバー（補剛部材）、５１…係止用突起、５２…セラミックス、５５…ステンレス鋼製カバー。   DESCRIPTION OF SYMBOLS 10 ... Reactor pressure vessel, 11 ... Core, 12 ... Core shroud, 13 ... Shroud support, 14 ... Shroud head, 15 ... Stand pipe, 16 ... Steam-water separator, 17 ... Steam dryer, 20 ... Pressure vessel lower head (Pressure vessel lower mirror), 21 ... penetrating member (control rod drive mechanism (CRD) housing), 22 ... control rod guide tube, 23 ... main steam nozzle, 24 ... water supply nozzle, 25 ... recirculation outlet nozzle, 26 ... re Circulating inlet nozzle, 28 ... penetrating part, 29 ... stub tube (support tube), 30 ... welded part, 31 ... core lower plenum, 33, 33A-33H ... welded part protection device, 35 ... metal cover container, 36 ... heat insulating material 37 ... Vertical rib (plate-shaped stiffening member), 38 ... Horizontal rib (plate-shaped stiffening member), 39 ... River (bar-shaped stiffening member), 40, 43, 45 ... Rib or river ( Rigid member), 41, 46 ... intermediate portion (uneven joint portion), 44 ... low melting point metal or resin material, 48 ... barrier coating, 50, 54 ... rib or river (stiffening member), 51 ... locking projection, 52 ... ceramics, 55 ... stainless steel cover.

Claims (10)

断熱材を覆った金属カバー容器を、原子炉圧力容器貫通部上の溶接部周囲に設置した溶接部保護装置を備え、
前記溶接部保護装置は、前記金属カバー容器の内部に補剛部材のリブあるいはリバーが配設されたことを特徴とする原子炉圧力容器。 A metal cover container covering the heat insulating material is provided with a welded part protection device installed around the welded part on the reactor pressure vessel penetration part,
The reactor pressure vessel according to claim 1, wherein the welded part protection device is provided with a rib or river of a stiffening member inside the metal cover vessel. 前記溶接部保護装置の金属カバー容器は、トーラス状あるいはドーナツ状に構成され、前記金属カバー容器の内部に、周方向に沿って等間隔に板状補剛部材の垂直リブが放射状に配設された請求項１に記載の原子炉圧力容器。 The metal cover container of the welded part protection device is formed in a torus shape or a donut shape, and the vertical ribs of the plate-shaped stiffening members are radially arranged in the metal cover container at equal intervals along the circumferential direction. The reactor pressure vessel according to claim 1. 前記溶接部保護装置の金属カバー容器は、トーラス状あるいはドーナツ状に構成され、前記金属カバー容器の内部に、板状補剛部材の水平リブがリング状あるいはワッシャ状に配設された請求項１に記載の原子炉圧力容器。 The metal cover container of the welded part protection device is configured in a torus shape or a donut shape, and a horizontal rib of a plate-shaped stiffening member is disposed in a ring shape or a washer shape inside the metal cover container. Reactor pressure vessel as described in 1. 前記溶接部保護装置の金属カバー容器は、トーラス状あるいはドーナツ状に構成され、前記金属カバー容器の内部に、板状補剛部材の複数のリバーが周方向に沿って等間隔にかつ放射状に配設された請求項１に記載の原子炉圧力容器。 The metal cover container of the welded part protection device is formed in a torus shape or a donut shape, and a plurality of ribs of a plate-shaped stiffening member are arranged radially at equal intervals in the circumferential direction inside the metal cover container. The reactor pressure vessel according to claim 1 provided. 前記リブあるいはリバーは、中間部が途中で凹凸結合されて弱化領域が構成された請求項１に記載の原子炉圧力容器。 2. The reactor pressure vessel according to claim 1, wherein the rib or the river has a weakened region formed by concavity and convexity in the middle portion. 前記リブあるいはリバーは、中間部の一部が低融点金属あるいは樹脂材で構成された請求項１に記載の原子炉圧力容器。 2. The reactor pressure vessel according to claim 1, wherein a part of an intermediate portion of the rib or the river is made of a low melting point metal or a resin material. 前記リブあるいはリバーは、遮熱コーティングが施されて被覆された請求項１に記載の原子炉圧力容器。 The reactor pressure vessel according to claim 1, wherein the rib or river is coated with a thermal barrier coating. 前記リブあるいはリバーは、全体がセラミックあるいは樹脂材で構成された請求項１に記載の原子炉圧力容器。 The reactor pressure vessel according to claim 1, wherein the rib or the river is entirely made of a ceramic or a resin material. 前記リブあるいはリバーは、セラミックをステンレス鋼製カバーで被覆して構成された請求項１に記載の原子炉圧力容器。 The reactor pressure vessel according to claim 1, wherein the rib or the river is configured by covering a ceramic with a stainless steel cover. 原子炉圧力容器貫通部上の溶接部により貫通部材を固定する一方、
断熱材を覆う金属カバー容器の内部に、補剛部材のリブあるいはリバーを配設した溶接部保護装置を準備し、
前記貫通部材を固定する溶接部の周囲に前記溶接部保護装置を外側から覆うように設置して、前記溶接保護装置を取り付けることを特徴とする原子炉圧力容器の溶接部保護装置の取付方法。 While fixing the penetrating member by the weld on the reactor pressure vessel penetration,
Prepare a welding part protection device in which ribs or rivers of stiffening members are arranged inside the metal cover container covering the heat insulating material,
A method for attaching a welded part protecting device for a reactor pressure vessel, wherein the welded protective device is installed around the welded part that fixes the penetrating member so as to cover the welded part from the outside.
JP2014207338A 2014-10-08 2014-10-08 Reactor pressure vessel and mounting method of welding protection device Pending JP2016075630A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106903397A (en) * 2017-03-31 2017-06-30 中国核工业第五建设有限公司 The method of welding AP1000 nuclear power station CV cylinders and penetration piece sleeve

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106903397A (en) * 2017-03-31 2017-06-30 中国核工业第五建设有限公司 The method of welding AP1000 nuclear power station CV cylinders and penetration piece sleeve
CN106903397B (en) * 2017-03-31 2019-07-19 中国核工业第五建设有限公司 The method for welding AP1000 nuclear power station CV cylinder and penetration piece sleeve

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