JP4094172B2

JP4094172B2 - underwater pump

Info

Publication number: JP4094172B2
Application number: JP14846899A
Authority: JP
Inventors: 俊三渡邊; 誠三上; 憲内田; 清文佐伯; 隆彦飯倉; 幸夫渡部; 直奈良林
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1999-05-27
Filing date: 1999-05-27
Publication date: 2008-06-04
Anticipated expiration: 2019-05-27
Also published as: JP2000338289A

Description

【０００１】
【発明の属する技術分野】
本発明は、圧力容器に設けられ、その容器内の炉水を循環させる水中ポンプに関する。
【０００２】
【従来の技術】
圧力容器、例えば原子炉圧力容器では、炉底部に水中ポンプ、具体的にはインターナルポンプを設置し、水中ポンプの駆動力により炉水（給水）を強請循環させ、炉心の核分裂の際のボイド率を調整し、原子炉熱出力の制御を行っている。
【０００３】
この水中ポンプは、図１５に示すように、炉胴体１のスタッドチューブ２に挿通され、炉胴体１と炉心シュラウド３との間に設置したポンプ部４と、炉胴体１の外側に設置したポンプ駆動部５とに区分けして構成されている。
【０００４】
ポンプ部４は、筒体６の内面シール部７に沿って着脱自在に装着させたウェアリング８内を回転するインペラ９と、インペラ９の回転力により案内された炉水（給水）の圧力を回復させて炉胴体１の炉底部側に供給するディフューザ１０とを備えている。なお、インペラ９は、その外周側をリング片１１で支持させるとともに、その内周側をポンプ軸１２のボス部１３に固設させている。また、ディフューザ１０は、筒体６に固設させている。
【０００５】
一方、ポンプ駆動部５は、その底部をカバー１４で塞ぐポンプケーシング１５内に、キャン１６を介装させてステータ１７とロータ１８とからなるウェットモータ１９を備えている。
【０００６】
他方、スタッドチューブ２内に挿通され、ポンプ部４とポンプ駆動部５とを互いに接続させるポンプ中間接続体２０は、ポンプ部４のディフューザ１０を支持するストレッチチューブ２１を備えるとともに、ストレッチチューブ２１をスタッドチューブ２に対し、取付け、取外しが自在にできるストレッチチューブナット２２を備えている。
【０００７】
また、ポンプ中間接続体２０は、ポンプ部４のポンプ軸１２とポンプ駆動部５のロータ１８とを互いに接続させる軸継手部２３の周辺の二次シール部２４を設け、二次シール部２４に二次シール加圧水管２５からのシール水を供給し、炉胴体１からの炉水（給水）をウェットモータ１９側に流出させないようになっている。
【０００８】
また、ポンプ駆動部５のポンプケーシング１５は、冷却水入口２６と冷却水出口２７とを備え、冷却水入口２６から供給された冷却水によりウェットモータ１９を冷却させた後、その冷却水を冷却水出口２７を介して系外に流出させている。
【０００９】
このように、従来の水中ポンプでは、容器内にポンプ部４を、容器外にポンプ駆動部５をそれぞれ区分けして設置し、配管系を削減させて効率の高い運転を行うとともに、溶接個所を少なくさせて検査時の作業員の労力を少なくさせるなどの数多くの改善を行ってきた。
【００１０】
【発明が解決しようとする課題】
図１５で示す従来の水中ポンプでは、次に述べるようなポンプ部４のインペラ９の振動問題がある。
【００１１】
従来、図１５で示す水中ポンプは、炉水をインペラ９からディフューザ１０に向って流出させる際、インペラ９の出口側の圧力が高いことも手伝って炉水としての漏水が筒体６とウェアリング８との間に形成する内面シール部７を介してインペラ９の入口側に向ってわずかに流出する。ポンプ軸１２は、インペラ内を流れる炉水の流水の変動で、センタ中心からわずかに偏位を繰り返し、すなわち振動として観測される。通常は、漏水による差圧軸受効果を受けて設置当初のセンタ中心から偏位しても、設置当初の位置に直ぐさま戻され、安定運転を行っている。
【００１２】
しかし、最近のＡＳＭＥペーパ（ＡｎＩｎｆｌｕｅｎｃｅｏｆＡｎｎｕｌａｒＳｅａｌＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｎｔｈｅＳｔａｂｉｌｉｔｙｏｆＶｅｒｔｉｃａｌＴｙｐｅＰｕｍｐｓｗｉｔｈＪｏｕｒｎａｌＢｅａｒｉｎｇｓＰＶＰ−ｖｏｌ．３６６，Ｐ２７９−２８６，ＡＳＭＥ，１９９８）によると、内面シール部７の入口側に固形物が付着し、この固形物の影響により漏水の流れに変動が発生し、インペラ９を支持するポンプ軸１２が当初の設置位置から変化し、その結果、ホワール振動等の不安定振動に発展したと、報告されている。
【００１３】
このような問題点を子細に考慮してみると、以下に示すことが実験により確認された。
【００１４】
図１６は、ポンプ部４のポンプ軸１２の偏位を示す模式図である。このうち、（ａ）は図１５のＡ−Ａ矢視方向から切断した平断面図を、（ｂ）は図１６の（ａ）のＢ−Ｂ矢視方向から切断した側断面図をそれぞれ示している。
【００１５】
インペラ９を支持するポンプ軸１２は、図１６の（ａ）に示すように、センタ中心Ｏ_１から矢印Ｅの方向に向ってセンタ中心Ｏ_２に偏位したとき、不安定振動へ発展した原因を調査してみると、図１６の（ｂ）に示すように、筒体６とイペンラ９の外側に設けたリング片１１との間に形成される内面シール部７の入口側に固形物ＳＰが付着・堆積していた。このため、炉水ＦＷがインペラ９の入口側から出口側に向って矢印のように流れる際、内面シール部７の入口ＩＮの圧力が高くなっているため、その一部が漏水ＬＳとして反転として内面シール部７内を出口ＥＸＴに向って流れる。このとき、内面シール部７の入口ＩＮに固形物ＳＰが付着・堆積していると、漏水ＬＳが断続的に流れ、ポンプ軸１２は、図１６の（ａ），（ｂ）に示すセンタ中心Ｏ_１を通る軸心ＳＣ_１からセンタ中心Ｏ_２を通る軸心ＳＣ_２に変位しても正常な差圧軸受効果が発生せず、不安定振動が発生するものと考えられる。
【００１６】
今、内面シール部７の入口ＩＮから出口ＥＸＴに向う圧力の変化を調査してみると、内面シール部７に固形物が付着・堆積していない場合、その圧力分布線図は、図１７に示すように、偏位方向圧力が反偏位方向圧力よりも高くなり、図１６の（ａ），（ｂ）に示すようにポンプ軸１２が一時的に偏位しても復原力が直ぐさま働くため、ポンプ軸１２を安定状態に維持させていた。
【００１７】
しかし、内面シール部７に固形物ＳＰの付着・堆積が増加すると、その圧力分布線図は、図１８に示すように、偏位方向圧力が反偏位方向圧力よりも下廻り、そのためポンプ軸１２を当初の設定位置からさらに偏位を促進させる傾向になっていた。
【００１８】
このように、従来の水中ポンプでは、内面シール部７に固形物ＳＰが付着・堆積すると、不安定振動が間断なく連続的に発生し、遂には危険状態になる問題点があった。
【００１９】
本発明は、このような事情に対処してなされたもので、内面シール部に固形物等の不純物が付着・堆積してもポンプ軸を設置当初の位置に維持させて安定運転を行わせた水中ポンプを提供することを目的とする。
【００２０】
【課題を解決するための手段】
本発明に係る水中ポンプは、上記目的を達成するために、請求項１に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記インペラの外側に固設するリング片と上記筒体の内面とで形成する内面シール部の、その筒体側の周方向に沿って設けた内周溝と、この内周溝に交差し、上記ポンプ軸の軸方向に沿って延びる導水溝と、この導水溝に連通し、上記筒体の周方向に沿って断続的に設けたポケット溝とを備えたものである。
【００２１】
本発明に係る水中ポンプは、上記目的を達成するために、請求項２に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記筒体の内面に着脱自在に装着するウェアリングと、上記インペラの外側に固設するリング片と上記ウェアリングの内面とで形成する内面シール部の、そのウェアリング側の周方向に沿って設けた内周溝と、この内周溝に交差し、上記ポンプ軸の軸方向に沿って延びる導水溝と、この導水溝に連通し、上記ウェアリングの周方向に沿って断続的に設けたポケット溝とを備えたものである。
【００２２】
本発明に係る水中ポンプは、上記目的を達成するために、請求項３に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記インペラの外側に固設するリング片と上記筒体の内面とで形成する内面シール部の、その筒体側の入口側に拡開通路を形成するとともに、この拡開通路に連通し、上記ポンプ軸の軸方向に沿って延びる導水溝と、この導水溝に連通し、上記筒体の周方向に沿って断続的に設けたポケット溝とを備え、上記拡開通路は、通路断面を上記導水溝に較べて相対的に大きくする構成にしたものである。
【００２３】
本発明に係る水中ポンプは、上記目的を達成するために、請求項４に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記筒体の内面に着脱自在に装着するウェアリングと、上記インペラの外側に固設するリング片と上記ウェアリングの内面とで形成する内面シール部の、そのウェアリング側の上記ポンプ軸の軸方向に沿って延びる導水溝と、この導水溝に連通し、上記ウェアリングの周方向に沿って断続的に設けたポケット溝と、上記ウェアリングと上記リング片とで形成する上記内面シール部の入口側に形成され、入口側端部で拡開する拡開通路とを備え、この拡開通路は、通路断面を上記導水溝に較べて相対的に大きくする構成にしたものである。
【００２４】
本発明に係る水中ポンプは、上記目的を達成するために、請求項５に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記インペラの外側に固設するリング片と上記筒体の内面とで形成する内面シール部の、その入口側に、入口側端部で拡開する拡開通路を形成し、その出口側に絞り通路を形成するとともに、上記拡開通路は、通路断面を上記内面シール部に較べて相対的に大きくする構成にしたものである。
【００２６】
本発明に係る水中ポンプは、上記目的を達成するために、請求項６に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記インペラの外側に固設するリング片と上記筒体の内面とで形成する内面シール部の上記ポンプ軸の軸方向に沿って延びる導水溝と、この導水溝に連通し、上記筒体の周方向に沿って断続的に設けたポケット溝と、上記内面シール部の、その入口側に形成した拡開通路と、その出口側に配置され、上記筒体の周方向に沿って設けたラビリンスシール片とを備え、上記拡開通路は、通路断面を上記導水溝に較べて相対的に大きくする構成にしたものである。
【００２７】
本発明に係る水中ポンプは、上記目的を達成するために、請求項７に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記筒体の内面に着脱自在に装着するウェアリングと、上記インペラの外側に固設するリング片と上記ウェアリングの内面とで形成する内面シール部の上記ポンプ軸の軸方向に沿って延びる導水溝と、この導水溝に連通し、上記ウェアリングの周方向に沿って断続的に設けたポケット溝と、上記ウェアリングと上記リング片とで形成する上記内面シール部の入口側に形成した拡開通路と、上記内面シール部の出口側に配置され、上記ウェアリングの周方向に沿って設けたラビリンスシール片とを備え、上記拡開通路は、通路断面を上記導水溝に較べて相対的に大きくする構成にしたものである。
【００２８】
本発明に係る水中ポンプは、上記目的を達成するために、請求項８に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記インペラの外側に固設するリング片と上記筒体の内面とで形成する内面シール部の、その入口側に拡開通路を形成するとともに、その出口側に絞り通路を形成する一方、その出口側に配置され、上記筒体の周方向に沿って設けたラビリンスシール片とを備え、上記拡開通路は、通路断面を上記内面シール部に較べて相対的に大きくする構成にしたものである。
【００２９】
本発明に係る水中ポンプは、上記目的を達成するために、請求項９に記載したように、ポンプ軸で支持されたインペラを収容する筒体を備えた水中ポンプにおいて、上記筒体の内面に着脱自在に装着するウェアリングと、上記インペラの外側に固設するリング片と上記ウェアリングの内面とで形成する内面シール部の、その入口側に拡開通路を形成するとともに、その出口側に絞り通路を形成する一方、その出口側に配置され、上記ウェアリングの周方向に沿って設けたラビリンスシール片とを備え、上記拡開通路は、通路断面を上記内面シール部に較べて相対的に大きくする構成にしたものである。
【００３０】
本発明に係る水中ポンプは、上記目的を達成するために、請求項１０に記載したように、インペラのリング片に対する拡開通路の距離をＬ_１とし、インペラのリング片に対する絞り通路の距離をＬ_０とするとき、絞り距離比Ｌ_１／Ｌ_０は、
【数２】
Ｌ_１／Ｌ_０＝２〜３
に設定したものである。
【００３１】
【発明の実施の形態】
以下、本発明に係る水中ポンプの実施形態を図面および図面に付した符号を引用して説明する。
【００３２】
図１は、本発明に係る水中ポンプの第１実施形態を示す概略部分縦断面図である。
【００３３】
本実施形態に係る水中ポンプは、環状の筒体３０にポンプ軸３１のボス部３２に固設したインペラ３３を収容する構成になっている。
【００３４】
また、筒体３０は、インペラ３３の下流側にディフューザ３４を固設させ、インペラ３３で回転力が与えられて静圧を失った炉水ＦＷをディフューザ３４で回復させて下流側に案内するようになっている。
【００３５】
一方、筒体３０は、その頭部側にインペラ３３の外側を支持するリング片３５との間に内面シール部３６を形成するとともに、内面シール部３６に横断して周方向に沿って連続的に形成する内周溝３７および断続的に形成するポケット溝３８とを備えている。
【００３６】
また、筒体３０は、内周溝３７に交差し、ポンプ軸３１の軸方向に向って長く延びる導水溝３９を備えるとともに、導水溝３９とポケット溝３８とを図２に示すように、互いに連通させる構成になっている。
【００３７】
このような構成を備えた水中ポンプにおいて、炉水（給水）ＦＷはインペラ３３からディフューザ３４を介して下流側に流れる際、導水溝３９からポケット溝３８にも流れる。ポケット溝３８に集められた炉水ＦＷは、インペラ３３の回転に伴って圧力が高まり、この圧力の高まりにより押圧力が発生し、この押圧力がインペラ３３のリング片３５に、いわゆるクサビ効果として与えてインペラ３３を安定状態に維持させるとともにシールとしても機能する。
【００３８】
ところで、水中ポンプの運転中、何らかの事情で、内面シール部３６の入口ＩＮ側に固形物が付着・堆積すると、炉水ＦＷの流れが悪くなる。このためインペラ３３のリング片３５に不均等な押圧力が発生し、これに伴ってインペラ３３に発生する圧力分布は、図１８で示したように、偏位方向圧力が反偏位方向圧力を下廻り、不安定振動が発生する。
【００３９】
本実施形態は、このような点を考慮したもので、筒体３０にその周方向に沿って連続的に内周溝３７を設けるとともに、内周溝３７に交差・連通させ、ポンプ軸３１の軸方向に向って長く延びる導水溝３９に連通させ、かつ筒体３０の周方向に沿って断続的にポケット溝３８を設け、内面シール部３６の入口ＩＮ側に、万一、固形物が付着・堆積しても、炉水ＦＷを内周溝３７、導水溝３９を介してポケット溝３８に集め、集めた炉水によりインペラ３３のリング片３５の全周に亘って均等に押圧力が発生する構成にしたものである。
【００４０】
図１２は、筒体３０のポケット溝３８の中央部において、炉水がインペラ３３のリング片３５に与える圧力分布を示す線図であり、この圧力分布線図から内面シール部３６の一部の領域を除いて偏位方向圧力が反偏位方向圧力を上廻ることが認められた。
【００４１】
このように、本実施形態によれば、筒体３０に内周溝３７、導水溝３９、ポケット溝３８を互いに連通させ、内面シール部３６の入口ＩＮ側の一部の領域に固形物が付着・堆積しても、他の溝から筒体３０の内面シール部３６の全域に亘って流れる構成にしたので、ポケット溝３８からインペラ３３のリング片３５に効果的な押圧力を確実に与えることができ、インペラ３３を支持するポンプ軸３１を安定状態に維持させることができる。
【００４２】
図３は、本発明に係る水中ポンプの第２実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００４３】
本実施形態に係る水中ポンプは、筒体３０の内周面の周方向に沿ってウェアリング４０を着脱自在に装着するとともに、このウェアリング４０に第１実施形態と同様に、内周溝３７、ポケット溝３８および導水溝３９を設け、これらを互いに連通させたものである。
【００４４】
このように、本実施形態では、内周溝３７、ポケット溝３８および導水溝３９を設けたウェアリング４０を筒体３０に着脱自在に装着させたので、第１実施形態と同様に、ポンプ軸３１を安定状態に維持させることと相俟って、インペラ等３３の交換を容易に行うことができ、その交換に要する作業時間を短くして作業者の労力を軽減させることができる。
【００４５】
図４は、本発明に係る水中ポンプの第３実施形態を示す概略部分縦断図面である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００４６】
本実施形態に係る水中ポンプは、第１実施形態と同様に、筒体３０にポケット溝３８および導水溝３９を設けるとともに、筒体３０の内面シール部３６の入口ＩＮ側をポンプ軸３１の軸方向に沿って拡開通路４１に形成し、拡開通路４１を導水溝３９を介してポケット溝３８に連通させたものである。
【００４７】
このように、本実施形態では、筒体３０の内面シール部３６の入口ＩＮ側にポンプ軸３１の軸方向に沿って拡開通路４１を形成し、拡開通路４１を導水溝３９を介してポケット溝３８に連通させたので、内面シール部３６の入口ＩＮ側に固形物が付着・堆積しても、炉水の流れの変化を低く抑えてポケット溝３８に炉水ＦＷを集めることができ、さらに固形物が付着・堆積していない拡開通路４１からの炉水ＦＷも加えてポケット溝３８に集められた炉水ＦＷでインペラ３３のリング片３５に与える押圧力を均一化することができる。
【００４８】
図１３は、筒体３０のポケット溝３８の炉水ＦＷからインペラ３３のリング片３５に与えられる圧力分布を示す線図であり、この圧力分布線図から偏位方向圧力が反偏位方向圧力を上廻ることが認められた。
【００４９】
したがって、本実施形態によれば、筒体３０の内面シール部３６を拡開通路４１に形成し、拡開通路４１を導水溝３９を介してポケット溝３８に連通させ、炉水ＦＷをポケット溝３８に確実に案内させたので、内面シール部３６の一部に固形物が付着・堆積してもインペラ３３のリング片３５に均一に押圧力を与えることができ、ポンプ軸３１を安定状態に維持させることができる。
【００５０】
図５は、本発明に係る水中ポンプの第４実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００５１】
本実施形態に係る水中ポンプは、第２実施形態と第３実施形態とを組み合わせたもので、ポケット溝３８、導水溝３９を設けたウェアリング４０を筒体３０に着脱自在に装着させるとともに、筒体３０の内面シール部３６の入口ＩＮ側をポンプ軸３１の軸方向に沿って拡開通路４１に形成し、拡開通路４１を導水溝３９を介してポケット溝３９に連通させたものである。
【００５２】
このように、本実施形態では、ポケット溝３８、導水溝３９を設けたウェアリング４０を筒体３０に着脱自在に装着させるとともに、筒体３０の内面シール部３６の入口ＩＮ側に拡開通路４１を形成し、拡開通路４１を導水溝３９を介してポケット溝３９に連通させたので、第３実施形態と同様に、ポンプ軸の安定維持と相俟ってインペラ３３等の交換作業を容易に行うことができる。
【００５３】
図６は、本発明に係る水中ポンプの第５実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号付している。
【００５４】
本実施形態に係る水中ポンプは、筒体３０とインペラ３３のリング片３５とで形成する内面シール部３６の、その入口ＩＮ側を拡開通路４１に形成するとともに、その出口ＥＸＴ側を絞り通路４２に形成したものである。この場合、インペラ３３のリング片３５に対する拡開通路４１の距離をＬ_１とし、インペラ３３のリング片３５に対する絞り通路４２の距離をＬ_０とするとき、絞り距離比Ｌ_１／Ｌ_０は、
【数３】
Ｌ_１／Ｌ_０＝２〜３
に設定されている。
【００５５】
このように、筒体３０の内面シール部３６の、その入口ＩＮ側を拡開通路４１に形成し、その出口ＥＸＴ側を絞り通路４２に形成し、絞り距離比Ｌ_１／Ｌ_０を
【数４】
Ｌ_１／Ｌ_０＝２〜３
の範囲に設定すると、内面シール部３６の炉水ＦＷによる圧力分布は、図１４に示すように、偏位方向圧力が反偏位方向圧力を上廻ることが認められた。
【００５６】
したがって、本実施形態によれば、内面シール部３６の入口ＩＮ側に固形物が付着・堆積しても拡開通路４１に形成するとともに、その出口ＥＸＴ側を絞り通路４２に形成し、常に偏位方向圧力が反偏位方向圧力よりも上廻る構成にしたので、ポンプ軸３１を安定状態に維持させることができる。
【００５７】
図７は、本発明に係る水中ポンプの第６実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００５８】
本実施形態に係る水中ポンプは、筒体３０の内周面の周方向に沿ってウェアリング４０の着脱自在に装着するとともに、ウェアリング４０とインペラ３３のリング片３５との間に形成された内面シール部３６の、その入口ＩＮ側を拡開通路４１に形成し、その出口ＥＸＴ側を絞り通路４２に形成する一方、インペラ３３のリング片３５に対する拡開通路４１の距離をＬ_１とし、インペラ３３のリング片３５に対する絞り通路４２の距離をＬ_０とするとき、絞り距離比Ｌ_１／Ｌ_０を、第５実施形態と同様に、
【数５】
Ｌ_１／Ｌ_０＝２〜３
に設定したものである。
【００５９】
したがって、本実施形態によれば、第５実施形態と同様に、ポンプ軸３１を安定状態に維持させることと相俟ってインペラ３３等の交換作業を容易に行うことができる。
【００６０】
図８は、本発明に係る水中ポンプの第７実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００６１】
本実施形態に係る水中ポンプは、筒体３０とインペラ３３のリング片３５とで形成する内面シール部３６の、その入口ＩＮ側を拡開通路４１に形成するとともに、その出口ＥＸＴ側とポンプ軸３１の軸方向に延びる導水溝３９に連通するポケット溝３８との間に、筒体３０の周方向に沿ってラビリンスシール片４３を設けたものである。
【００６２】
本実施形態によれば、内面シール部３６の入口ＩＮ側を拡開通路４１に形成するとともに、その出口ＥＸＴ側にラビリンスシール片４３を設けたので、その入口ＩＮ側に固形物が付着・堆積しても炉水ＦＷの漏水の流れに影響を与えることもなく、また、流入した漏水を内面シール部３６で閉じ込めてエネルギ損失を少なくさせることができる。
【００６３】
図９は、本発明に係る水中ポンプの第８実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００６４】
本実施形態に係る水中ポンプは、筒体３０の内周面の周方向に沿ってウェアリング４０を着脱自在に装着するとともに、ウェアリング４０とインペラ３３のリング片３５との間に形成された内面シール部３６の、その入口ＩＮ側を拡開通路４１に形成し、その出口ＥＸＴ側とポンプ軸３１の軸方向に伸びる導水溝３９に連通するポケット溝３８との間に、筒体３０の週方向に沿ってラビリンスシール片４３を設けたものである。
【００６５】
本実施形態によれば、筒体３０にウェアリング４０を着脱自在に装着するとともに、内面シール部３６の入口ＩＮ側に拡開通路４１を形成し、内面シール部３６の出口ＥＸＴ側にラビリンスシール片４３を設けたので、インペラ３３の交換作業を容易に行うことができ、炉水ＦＷの漏水を内面シール部３６で閉じ込めてエネルギ損失を少なくさせることができる。
【００６６】
図１０は、本発明に係る水中ポンプの第９実施形態を示す概略部分縦断面図である。なお、第１実施形態の構成部分と同一部分には同一符号を付している。
【００６７】
本実施形態に係る水中ポンプは、筒体３０とインペラ３３のリング片３５とで形成する内面シール部３６の、その入口ＩＮ側を拡開通路４１に形成するとともに、その出口ＥＸＴ側を絞り通路４２に形成し、さらにラビリンスシール片４３を筒体３０の周方向に沿って設けたものである。
【００６８】
また、本実施形態に係る水中ポンプは、インペラ３３のリング片３５に対する拡開通路４１の距離をＬ_１とし、インプラ３３のリング片３５に対する絞り通路４２の距離をＬ_０とするとき、絞り距離比Ｌ_１／Ｌ_０は、
【数６】
Ｌ_１／Ｌ_０＝２〜３
に設定したものである。
【００６９】
このように、実施形態によれば、内面シール部３６のその入口ＩＮ側を拡開通路４１に、その出口ＥＸＴ側を絞り通路４２にそれぞれ形成し、さらにその出口ＥＸＴ側にラビリンスシール片４３を設ける一方、インペラ３３のリング片３５に対する拡開通路４１の距離Ｌ_１とインペラ３３のリング片３５に対する絞り通路４２の距離Ｌ_０との絞り距離比Ｌ_１／Ｌ_０を、Ｌ_１／Ｌ_０＝２〜３に設定したので、ポンプ軸３１を安定状態に維持させるとともに、内面シール部３６に流入した炉水ＦＷの漏水を確実に閉じ込めてエネルギ損失を少なくさせることができる。
【００７０】
なお、本実施形態では、筒体３０とインペラ３３のリング片３５とで形成される内面シール部３６の、その入口ＩＮ側に拡開通路４１を形成し、その出口ＥＸＴ側に絞り通路４２を形成し、さらにその出口側にラビリンスシール片４３を設けているが、この実施形態に限らず、例えば図１１に示すように、筒体３０の内周面の周方向に沿ってウェアリング４０を着脱自在に装着し、このウェアリング４０とインペラ３３のリング片３５との間に形成される内面シール部３６に、第９実施形態で示した拡開通路４１、絞り通路４２およびラビリンスシール片４３を設けるとともに、拡開通路４１と絞り通路４２との絞り距離比Ｌ_１／Ｌ_０を、Ｌ_１／Ｌ_０＝２〜３に設定しても良い。
【００７１】
【発明の効果】
以上の説明のとおり、本発明に係る水中ポンプは、インペラを収容する筒体および筒体に着脱自在に装着したウェアリングのうち、いずれか一方に炉水の漏水を効果的に案内する通路手段、溝手段、封水手段を適宜に組み合わせて設け、通路手段に固形物が付着・堆積しても漏水の流れに悪影響を与えない構成にしたので、インペラを支持するポンプ軸に不安定振動を与えることなく安定状態に維持させることができる。
【図面の簡単な説明】
【図１】本発明に係る水中ポンプの第１実施形態を示す概略部分縦断面図。
【図２】図１のＣ−Ｃ矢視方向から切断した平断面図。
【図３】本発明に係る水中ポンプの第２実施形態を示す概略部分縦断面図。
【図４】本発明に係る水中ポンプの第３実施形態を示す概略部分縦断面図。
【図５】本発明に係る水中ポンプの第４実施形態を示す概略部分縦断面図。
【図６】本発明に係る水中ポンプの第５実施形態を示す概略部分縦断面図。
【図７】本発明に係る水中ポンプの第６実施形態を示す概略部分縦断面図。
【図８】本発明に係る水中ポンプの第７実施形態を示す概略部分縦断面図。
【図９】本発明に係る水中ポンプの第８実施形態を示す概略部分縦断面図。
【図１０】本発明に係る水中ポンプの第９実施形態を示す概略部分縦断面図。
【図１１】本発明に係る水中ポンプの第１０実施形態を示す概略部分縦断面図。
【図１２】本発明に係る水中ポンプの第１実施形態で得られた内面シール部の圧力分布線図。
【図１３】本発明に係る水中ポンプの第３実施形態で得られた内面シール部の圧力分布線図。
【図１４】本発明に係る水中ポンプの第５実施形態で得られた内面シール部の圧力分布線図。
【図１５】従来の水中ポンプを示す概略縦断面図。
【図１６】従来の水中ポンプにおけるポンプ軸の偏位を示す模式図で、（ａ）は図１５のＡ−Ａ矢視方向から切断した平断面図を（ｂ）は図１６の（ａ）のＢ−Ｂ矢視方向から切断した側断面図をそれぞれ示す。
【図１７】従来の水中ポンプにおけるポンプ軸を安定状態に維持させる内面シール部の圧力分布線図。
【図１８】従来の水中ポンプにおけるポンプ軸を不安定状態にさせる内面シール部の圧力分布線図。
【符号の説明】
１炉胴体
２スタッドチューブ
３炉心シュラウド
４ポンプ部
５ポンプ駆動部
６筒体
７内面シール部
８ウェアリング
９インペラ
１０ディフューザ
１１リング片
１２ポンプ軸
１３ボス部
１４カバー
１５ポンプケーシング
１６キャン
１７ステータ
１８ロータ
１９ウェットモータ
２０ポンプ中間接続体
２１ストレッチチューブ
２２ストレッチチューブナット
２３軸継手部
２４二次シール部
２５二次シール加圧水管
２６冷却水入口
２７冷却水出口
３０筒体
３１ポンプ軸
３２ボス部
３３インペラ
３４ディフューザ
３５リング片
３６内面シール部
３７内周溝
３８ポケット溝
３９導水溝
４０ウェアリング
４１拡開通路
４２絞り通路
４３ラビリンスシール片[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a submersible pump that is provided in a pressure vessel and circulates reactor water in the vessel.
[0002]
[Prior art]
In a pressure vessel, for example, a reactor pressure vessel, a submersible pump, specifically an internal pump, is installed at the bottom of the reactor. The reactor heat output is controlled by adjusting the rate.
[0003]
As shown in FIG. 15, this submersible pump is inserted into the stud tube 2 of the furnace body 1, a pump unit 4 installed between the furnace body 1 and the core shroud 3, and a pump installed outside the furnace body 1. It is configured to be divided into the drive unit 5.
[0004]
The pump unit 4 is configured to reduce the pressure of the impeller 9 rotating in the wear ring 8 detachably mounted along the inner surface seal portion 7 of the cylindrical body 6 and the pressure of the reactor water (feed water) guided by the rotational force of the impeller 9. And a diffuser 10 which is recovered and supplied to the furnace bottom side of the furnace body 1. The impeller 9 has an outer peripheral side supported by the ring piece 11 and an inner peripheral side fixed to the boss portion 13 of the pump shaft 12. Further, the diffuser 10 is fixed to the cylindrical body 6.
[0005]
On the other hand, the pump drive unit 5 includes a wet motor 19 including a stator 17 and a rotor 18 with a can 16 interposed in a pump casing 15 whose bottom is covered with a cover 14.
[0006]
On the other hand, a pump intermediate connector 20 that is inserted into the stud tube 2 and connects the pump unit 4 and the pump drive unit 5 to each other includes a stretch tube 21 that supports the diffuser 10 of the pump unit 4, and the stretch tube 21. A stretch tube nut 22 that can be freely attached to and detached from the stud tube 2 is provided.
[0007]
Further, the pump intermediate connector 20 is provided with a secondary seal portion 24 around the shaft coupling portion 23 that connects the pump shaft 12 of the pump portion 4 and the rotor 18 of the pump drive portion 5 to each other. The seal water from the secondary seal pressurized water pipe 25 is supplied so that the reactor water (feed water) from the furnace body 1 does not flow out to the wet motor 19 side.
[0008]
The pump casing 15 of the pump drive unit 5 includes a cooling water inlet 26 and a cooling water outlet 27, and after cooling the wet motor 19 with the cooling water supplied from the cooling water inlet 26, the cooling water is cooled. It flows out of the system through the water outlet 27.
[0009]
As described above, in the conventional submersible pump, the pump unit 4 is installed inside the container and the pump drive unit 5 is installed outside the container, and the piping system is reduced to perform highly efficient operation. Many improvements have been made, such as reducing the amount of labor required during inspections.
[0010]
[Problems to be solved by the invention]
The conventional submersible pump shown in FIG. 15 has a vibration problem of the impeller 9 of the pump unit 4 as described below.
[0011]
Conventionally, in the submersible pump shown in FIG. 15, when the reactor water flows out from the impeller 9 toward the diffuser 10, leakage of the reactor water as the reactor body 6 and the wear ring is also helped by the high pressure on the outlet side of the impeller 9. 8 flows out slightly toward the inlet side of the impeller 9 through the inner surface seal portion 7 formed between the two. The pump shaft 12 is observed as vibrations, that is, a slight deviation from the center center due to fluctuations in the flow of reactor water flowing in the impeller. Normally, even if it deviates from the center center at the time of installation due to the differential pressure bearing effect due to water leakage, it is returned to the initial position immediately and stable operation is performed.
[0012]
However, recent ASME papers (An Influencing of Annular Seal Characteristics on the Stability of Vertical Type Pumps with Journal Bearings PVP-vol. 986, P279-P As a result of this solid matter, the flow of water leaked and the pump shaft 12 supporting the impeller 9 changed from the initial installation position, and as a result, it developed into unstable vibration such as whirl vibration. ,It has been reported.
[0013]
Considering these problems in detail, the following was confirmed by experiments.
[0014]
FIG. 16 is a schematic diagram showing the displacement of the pump shaft 12 of the pump unit 4. Among these, (a) is a plane sectional view cut from the direction of arrows AA in FIG. 15, and (b) is a side sectional view cut from the direction of arrows BB in FIG. ing.
[0015]
As shown in FIG. 16A, the pump shaft 12 that supports the impeller 9 has a center center O. ₁ From the center O to the direction of arrow E ₂ When the cause of the unstable vibration is investigated, it is formed between the cylindrical body 6 and the ring piece 11 provided outside the impeller 9 as shown in FIG. The solid SP was deposited and deposited on the inlet side of the inner surface seal portion 7 to be formed. For this reason, when the reactor water FW flows from the inlet side to the outlet side of the impeller 9 as indicated by an arrow, the pressure at the inlet IN of the inner surface seal portion 7 is high, and a part of the pressure is reversed as the water leakage LS. It flows in the inner surface seal portion 7 toward the outlet EXT. At this time, if the solid matter SP adheres and accumulates at the inlet IN of the inner surface seal portion 7, the water leakage LS flows intermittently, and the pump shaft 12 is centered at the center shown in FIGS. 16 (a) and 16 (b). O ₁ Axis SC passing through ₁ To center O ₂ Axis SC passing through ₂ It is considered that the normal differential pressure bearing effect does not occur even if it is displaced, and unstable vibration occurs.
[0016]
Now, when the change in the pressure from the inlet IN to the outlet EXT of the inner surface seal portion 7 is examined, when solid matter is not adhered or deposited on the inner surface seal portion 7, the pressure distribution diagram is shown in FIG. As shown in FIG. 16, the displacement direction pressure becomes higher than the anti-deviation direction pressure, and even if the pump shaft 12 is temporarily displaced as shown in FIGS. In order to work, the pump shaft 12 was maintained in a stable state.
[0017]
However, when the adhesion / deposition of the solid SP increases on the inner surface seal portion 7, the pressure distribution diagram shows that the displacement direction pressure is lower than the anti-deviation direction pressure, as shown in FIG. Tended to promote further deviation from the initial set position.
[0018]
As described above, in the conventional submersible pump, when solid matter SP adheres to and accumulates on the inner surface seal portion 7, unstable vibration continuously occurs without interruption, and finally there is a problem that it becomes a dangerous state.
[0019]
The present invention has been made in response to such a situation, and even when impurities such as solid matter adhere to and accumulate on the inner surface seal portion, the pump shaft is maintained at the initial position of installation to perform stable operation. The purpose is to provide a submersible pump.
[0020]
[Means for Solving the Problems]
In order to achieve the above object, a submersible pump according to the present invention is a submersible pump comprising a cylindrical body that houses an impeller supported by a pump shaft, as described in claim 1, and is fixed to the outside of the impeller. An inner circumferential groove provided along the circumferential direction of the cylinder side of the inner surface seal portion formed by the ring piece to be installed and the inner surface of the cylinder body, and intersecting the inner circumferential groove and extending in the axial direction of the pump shaft A water guide groove extending along the pocket and a pocket groove communicating with the water guide groove and provided intermittently along the circumferential direction of the cylindrical body are provided.
[0021]
In order to achieve the above object, the submersible pump according to the present invention is a submersible pump comprising a cylindrical body that houses an impeller supported by a pump shaft. An inner circumferential groove provided along a circumferential direction on the wear ring side of an inner seal portion formed by a wear ring to be detachably mounted, a ring piece fixed to the outer side of the impeller, and an inner surface of the wear ring; A water guide groove that intersects the inner peripheral groove and extends along the axial direction of the pump shaft, and a pocket groove that communicates with the water guide groove and is provided intermittently along the circumferential direction of the wear ring. Is.
[0022]
In order to achieve the above object, a submersible pump according to the present invention includes a cylindrical body that houses an impeller supported by a pump shaft, as described in claim 3. underwater pump And forming an expansion passage on the inlet side of the inner surface seal portion formed by the ring piece fixed to the outside of the impeller and the inner surface of the cylinder, and in the expansion passage Communication A water guide groove extending along the axial direction of the pump shaft, and a pocket groove communicating with the water guide groove and provided intermittently along the circumferential direction of the cylinder. The expanded passage has a structure in which the passage cross-section is relatively larger than the water guide groove. Is.
[0023]
In order to achieve the above object, the submersible pump according to the present invention is a submersible pump comprising a cylinder that houses an impeller supported by a pump shaft. A water guide extending along the axial direction of the pump shaft on the wear ring side of an inner seal portion formed by a wear ring to be detachably attached, a ring piece fixed to the outer side of the impeller, and an inner surface of the wear ring Formed on the inlet side of the inner surface seal portion formed by the groove, the pocket groove communicated with the water guide groove, intermittently provided along the circumferential direction of the wear ring, and the wear ring and the ring piece, Expands at the entrance end An expansion passage is provided, and the expansion passage has a configuration in which the passage cross section is relatively larger than the water guide groove.
[0024]
In order to achieve the above object, the submersible pump according to the present invention is a submersible pump comprising a cylindrical body that houses an impeller supported by a pump shaft, as described in claim 5, and is fixed to the outside of the impeller. On the inlet side of the inner seal portion formed by the ring piece to be installed and the inner surface of the cylinder, Expands at the entrance end An expanded passage is formed, a throttle passage is formed on the outlet side thereof, and the expanded passage is configured to have a relatively larger passage cross section than the inner surface seal portion.
[0026]
In order to achieve the above object, the submersible pump according to the present invention includes: Claim 6 As described above, in the submersible pump provided with the cylindrical body that accommodates the impeller supported by the pump shaft, the inner seal portion formed by the ring piece fixed to the outer side of the impeller and the inner surface of the cylindrical body A water guide groove extending along the axial direction of the pump shaft, a pocket groove communicating with the water guide groove and provided intermittently along the circumferential direction of the cylindrical body, and formed on the inlet side of the inner surface seal portion. An expansion passage and a labyrinth seal piece arranged along the circumferential direction of the cylindrical body on the outlet side thereof The expanded passage has a structure in which the passage cross-section is relatively larger than the water guide groove. Is.
[0027]
In order to achieve the above object, the submersible pump according to the present invention includes: Claim 7 In the submersible pump provided with the cylindrical body that stores the impeller supported by the pump shaft, a wear ring that is detachably attached to the inner surface of the cylindrical body, and a ring piece that is fixed to the outside of the impeller And a water guide groove extending along the axial direction of the pump shaft of the inner surface seal portion formed by the inner surface of the wear ring, and a pocket provided intermittently along the circumferential direction of the wear ring, communicating with the water guide groove An expansion passage formed on the inlet side of the inner surface seal portion formed by the groove, the wear ring and the ring piece, and disposed on the outlet side of the inner surface seal portion, provided along the circumferential direction of the wear ring A labyrinth seal piece The expanded passage has a structure in which the passage cross-section is relatively larger than the water guide groove. Is.
[0028]
In order to achieve the above object, the submersible pump according to the present invention includes: Claim 8 As described above, in the submersible pump provided with the cylindrical body that accommodates the impeller supported by the pump shaft, the inner seal portion formed by the ring piece fixed to the outer side of the impeller and the inner surface of the cylindrical body, A labyrinth seal piece provided along the circumferential direction of the cylindrical body is formed on the outlet side while forming an expansion passage on the inlet side and a throttle passage on the outlet side. The expanded passage has a configuration in which the cross section of the passage is relatively larger than the inner seal portion. Is.
[0029]
In order to achieve the above object, the submersible pump according to the present invention includes: Claim 9 In the submersible pump provided with the cylindrical body that stores the impeller supported by the pump shaft, a wear ring that is detachably attached to the inner surface of the cylindrical body, and a ring piece that is fixed to the outside of the impeller And an inner surface seal portion formed by the inner surface of the wear ring, an expansion passage is formed on the inlet side thereof, and a throttle passage is formed on the outlet side thereof. Labyrinth seal piece provided along the direction The expanded passage has a configuration in which the cross section of the passage is relatively larger than the inner seal portion. Is.
[0030]
In order to achieve the above object, the submersible pump according to the present invention includes: Claim 10 The distance of the expansion passage relative to the ring piece of the impeller is L ₁ And the distance of the throttle passage with respect to the ring piece of the impeller is L ₀ When the aperture distance ratio L ₁ / L ₀ Is
[Expression 2]
L ₁ / L ₀ = 2 to 3
Is set.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the submersible pump according to the present invention will be described with reference to the drawings and reference numerals attached to the drawings.
[0032]
FIG. 1 is a schematic partial longitudinal sectional view showing a first embodiment of a submersible pump according to the present invention.
[0033]
The submersible pump according to the present embodiment is configured to accommodate an impeller 33 fixed to a boss portion 32 of a pump shaft 31 in an annular cylinder 30.
[0034]
Further, the cylindrical body 30 has a diffuser 34 fixed to the downstream side of the impeller 33, and the reactor water FW that has lost the static pressure due to the rotational force applied by the impeller 33 is recovered by the diffuser 34 and guided downstream. In Has become .
[0035]
On the other hand, the cylindrical body 30 is formed with an inner surface seal portion 36 between itself and a ring piece 35 that supports the outer side of the impeller 33 on the head side, and is continuous along the circumferential direction across the inner surface seal portion 36. An inner circumferential groove 37 formed intermittently and a pocket groove 38 formed intermittently.
[0036]
Further, the cylindrical body 30 includes a water guide groove 39 that intersects the inner peripheral groove 37 and extends long in the axial direction of the pump shaft 31, and the water guide groove 39 and the pocket groove 38 are mutually connected as shown in FIG. It is configured to communicate.
[0037]
In the submersible pump having such a configuration, the reactor water (feed water) FW also flows from the water guide groove 39 to the pocket groove 38 when flowing from the impeller 33 through the diffuser 34 to the downstream side. The reactor water FW collected in the pocket groove 38 increases in pressure with the rotation of the impeller 33, and a pressing force is generated by the increase in the pressure. This pressing force is applied to the ring piece 35 of the impeller 33 as a so-called wedge effect. The impeller 33 is provided to maintain the stable state, and also functions as a seal.
[0038]
By the way, if the solid matter adheres and accumulates on the inlet IN side of the inner surface seal portion 36 for some reason during operation of the submersible pump, the flow of the reactor water FW becomes worse. Therefore, an uneven pressing force is generated in the ring piece 35 of the impeller 33, and the pressure distribution generated in the impeller 33 in accordance with this is shown in FIG. Underwater, unstable vibration occurs.
[0039]
In the present embodiment, such a point is taken into consideration, and the cylindrical body 30 is provided with the inner circumferential groove 37 continuously along the circumferential direction, and intersects and communicates with the inner circumferential groove 37 so that the pump shaft 31 A pocket groove 38 is intermittently provided along the circumferential direction of the cylindrical body 30 so as to communicate with a water guide groove 39 extending in the axial direction, and a solid matter should adhere to the inlet IN side of the inner surface seal portion 36. Even if it accumulates, the reactor water FW is collected in the pocket groove 38 via the inner circumferential groove 37 and the water guide groove 39, and the collected reactor water generates a uniform pressing force over the entire circumference of the ring piece 35 of the impeller 33. It is the structure which does.
[0040]
FIG. 12 is a diagram showing a pressure distribution that the reactor water gives to the ring piece 35 of the impeller 33 in the central portion of the pocket groove 38 of the cylindrical body 30. From this pressure distribution diagram, a part of the inner surface seal portion 36 is shown. Except for the region, it was found that the displacement pressure exceeded the anti-deviation pressure.
[0041]
As described above, according to the present embodiment, the inner circumferential groove 37, the water guide groove 39, and the pocket groove 38 are communicated with each other to the cylindrical body 30, and solid matter adheres to a partial region on the inlet IN side of the inner surface seal portion 36. -Even if it accumulates, since it was made the structure which flows over the whole region of the inner surface seal part 36 of the cylinder 30 from another groove | channel, an effective pressing force is reliably given to the ring piece 35 of the impeller 33 from the pocket groove | channel 38. The pump shaft 31 that supports the impeller 33 can be maintained in a stable state.
[0042]
FIG. 3 is a schematic partial longitudinal sectional view showing a second embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0043]
In the submersible pump according to the present embodiment, the wear ring 40 is detachably mounted along the circumferential direction of the inner peripheral surface of the cylindrical body 30, and the inner peripheral groove 37 is attached to the wear ring 40 as in the first embodiment. The pocket groove 38 and the water guide groove 39 are provided and communicated with each other.
[0044]
Thus, in this embodiment, since the wear ring 40 provided with the inner circumferential groove 37, the pocket groove 38, and the water guide groove 39 is detachably attached to the cylindrical body 30, the pump shaft as in the first embodiment. Combined with maintaining 31 in a stable state, the impeller 33 and the like can be easily replaced, and the work time required for the replacement can be shortened to reduce the labor of the operator.
[0045]
FIG. 4 is a schematic partial longitudinal sectional view showing a third embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0046]
As in the first embodiment, the submersible pump according to the present embodiment is provided with the pocket groove 38 and the water guide groove 39 in the cylindrical body 30, and the inlet IN side of the inner surface seal portion 36 of the cylindrical body 30 is connected to the shaft of the pump shaft 31. The expansion passage 41 is formed along the direction, and the expansion passage 41 is communicated with the pocket groove 38 through the water guide groove 39.
[0047]
As described above, in this embodiment, the expansion passage 41 is formed along the axial direction of the pump shaft 31 on the inlet IN side of the inner surface seal portion 36 of the cylindrical body 30, and the expansion passage 41 is interposed via the water guide groove 39. Since it is connected to the pocket groove 38, the reactor water FW can be collected in the pocket groove 38 by suppressing a change in the flow of the reactor water even if solid matter adheres and accumulates on the inlet IN side of the inner surface seal portion 36. Furthermore, the pressing force applied to the ring piece 35 of the impeller 33 by the reactor water FW collected in the pocket groove 38 in addition to the reactor water FW from the expanded passage 41 where no solid matter adheres or accumulates can be made uniform. it can.
[0048]
FIG. 13 is a diagram showing a pressure distribution applied from the reactor water FW in the pocket groove 38 of the cylindrical body 30 to the ring piece 35 of the impeller 33. From this pressure distribution diagram, the displacement direction pressure is the anti-deviation direction pressure. It was recognized that
[0049]
Therefore, according to the present embodiment, the inner surface seal portion 36 of the cylindrical body 30 is formed in the expansion passage 41, the expansion passage 41 is communicated with the pocket groove 38 via the water guide groove 39, and the reactor water FW is made into the pocket groove. 38 is surely guided so that even if solid matter adheres to and accumulates on a part of the inner surface seal portion 36, it is possible to uniformly apply a pressing force to the ring piece 35 of the impeller 33, and the pump shaft 31 is brought into a stable state. Can be maintained.
[0050]
FIG. 5 is a schematic partial longitudinal sectional view showing a fourth embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0051]
The submersible pump according to the present embodiment is a combination of the second embodiment and the third embodiment. The wear ring 40 provided with the pocket groove 38 and the water guide groove 39 is detachably attached to the cylindrical body 30. The inlet IN side of the inner surface seal portion 36 of the cylindrical body 30 is formed in the expansion passage 41 along the axial direction of the pump shaft 31, and the expansion passage 41 is communicated with the pocket groove 39 through the water guide groove 39. is there.
[0052]
As described above, in the present embodiment, the wear ring 40 provided with the pocket groove 38 and the water guide groove 39 is detachably attached to the cylindrical body 30, and the expansion passage is provided on the inlet IN side of the inner surface seal portion 36 of the cylindrical body 30. 41, and the expansion passage 41 is communicated with the pocket groove 39 via the water guide groove 39. Therefore, as in the third embodiment, the replacement work of the impeller 33 and the like can be performed together with the stable maintenance of the pump shaft. It can be done easily.
[0053]
FIG. 6 is a schematic partial longitudinal sectional view showing a fifth embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the part same as the component of 1st Embodiment.
[0054]
The submersible pump according to the present embodiment forms the inlet IN side of the inner surface seal portion 36 formed by the cylindrical body 30 and the ring piece 35 of the impeller 33 in the expansion passage 41 and the throttle passage on the outlet EXT side thereof. 42 is formed. In this case, the distance of the expansion passage 41 to the ring piece 35 of the impeller 33 is set to L ₁ And the distance of the throttle passage 42 with respect to the ring piece 35 of the impeller 33 is L ₀ When the aperture distance ratio L ₁ / L ₀ Is
[Equation 3]
L ₁ / L ₀ = 2 to 3
Is set to
[0055]
In this way, the inner surface seal portion 36 of the cylindrical body 30 is formed with its inlet IN side in the expanded passage 41 and its outlet EXT side is formed in the throttle passage 42, and the throttle distance ratio L ₁ / L ₀ The
[Expression 4]
L ₁ / L ₀ = 2 to 3
As shown in FIG. 14, it was recognized that the pressure distribution due to the reactor water FW at the inner surface seal portion 36 was higher than the anti-deviation direction pressure.
[0056]
Therefore, according to the present embodiment, even if solid matter adheres and accumulates on the inlet IN side of the inner surface seal portion 36, it is formed in the expanded passage 41, and the outlet EXT side is formed in the throttle passage 42, so that it is always biased. Since the displacement pressure is higher than the anti-deviation pressure, the pump shaft 31 can be maintained in a stable state.
[0057]
FIG. 7 is a schematic partial longitudinal sectional view showing a sixth embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0058]
The submersible pump according to the present embodiment is mounted between the wear ring 40 and the ring piece 35 of the impeller 33 while the wear ring 40 is detachably mounted along the circumferential direction of the inner peripheral surface of the cylindrical body 30. The inner side seal portion 36 is formed with the inlet IN side in the expanded passage 41 and the outlet EXT side is formed in the throttle passage 42, while the distance of the expanded passage 41 to the ring piece 35 of the impeller 33 is set to L ₁ And the distance of the throttle passage 42 with respect to the ring piece 35 of the impeller 33 is L ₀ When the aperture distance ratio L ₁ / L ₀ As in the fifth embodiment,
[Equation 5]
L ₁ / L ₀ = 2 to 3
Is set.
[0059]
Therefore, according to the present embodiment, similar to the fifth embodiment, it is possible to easily replace the impeller 33 and the like in combination with maintaining the pump shaft 31 in a stable state.
[0060]
FIG. 8 is a schematic partial longitudinal sectional view showing a seventh embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0061]
The submersible pump according to the present embodiment forms the inlet IN side of the inner surface seal portion 36 formed by the cylindrical body 30 and the ring piece 35 of the impeller 33 in the expanded passage 41, and the outlet EXT side and the pump shaft. A labyrinth seal piece 43 is provided along the circumferential direction of the cylindrical body 30 between the pocket groove 38 communicating with the water guide groove 39 extending in the axial direction of 31.
[0062]
According to the present embodiment, since the inlet IN side of the inner surface seal portion 36 is formed in the expansion passage 41 and the labyrinth seal piece 43 is provided on the outlet EXT side, solid matter adheres and accumulates on the inlet IN side. Even if it does not affect the flow of water leaked from the reactor water FW, the leaked water can be confined by the inner surface seal portion 36 to reduce energy loss.
[0063]
FIG. 9 is a schematic partial longitudinal sectional view showing an eighth embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0064]
The submersible pump according to the present embodiment is formed between the wear ring 40 and the ring piece 35 of the impeller 33 while the wear ring 40 is detachably mounted along the circumferential direction of the inner peripheral surface of the cylindrical body 30. The inner side seal portion 36 has an inlet IN side formed in an expanded passage 41, and the cylindrical body 30 is formed between the outlet EXT side and a pocket groove 38 communicating with a water guide groove 39 extending in the axial direction of the pump shaft 31. A labyrinth seal piece 43 is provided along the week direction.
[0065]
According to the present embodiment, the wear ring 40 is detachably attached to the cylindrical body 30, the expanded passage 41 is formed on the inlet IN side of the inner surface seal portion 36, and the labyrinth seal is disposed on the outlet EXT side of the inner surface seal portion 36. Since the piece 43 is provided, the replacement work of the impeller 33 can be easily performed, and the leakage of the reactor water FW can be confined by the inner surface seal portion 36 to reduce energy loss.
[0066]
FIG. 10 is a schematic partial longitudinal sectional view showing a ninth embodiment of the submersible pump according to the present invention. In addition, the same code | symbol is attached | subjected to the same part as the component of 1st Embodiment.
[0067]
The submersible pump according to the present embodiment forms the inlet IN side of the inner surface seal portion 36 formed by the cylindrical body 30 and the ring piece 35 of the impeller 33 in the expansion passage 41 and the throttle passage on the outlet EXT side thereof. Further, a labyrinth seal piece 43 is provided along the circumferential direction of the cylindrical body 30.
[0068]
Further, the submersible pump according to the present embodiment sets the distance of the expansion passage 41 to the ring piece 35 of the impeller 33 as L. ₁ And the distance of the throttle passage 42 with respect to the ring piece 35 of the impeller 33 is L ₀ When the aperture distance ratio L ₁ / L ₀ Is
[Formula 6]
L ₁ / L ₀ = 2 to 3
Is set.
[0069]
As described above, according to the embodiment, the inlet IN side of the inner surface seal portion 36 is formed in the expansion passage 41, the outlet EXT side thereof is formed in the throttle passage 42, and the labyrinth seal piece 43 is further formed on the outlet EXT side. On the other hand, the distance L of the expansion passage 41 with respect to the ring piece 35 of the impeller 33 ₁ And the distance L of the throttle passage 42 with respect to the ring piece 35 of the impeller 33 ₀ Aperture distance ratio L ₁ / L ₀ , L ₁ / L ₀ Since it is set to = 2 to 3, the pump shaft 31 can be maintained in a stable state, and the leakage of the reactor water FW flowing into the inner surface seal portion 36 can be reliably confined to reduce energy loss.
[0070]
In the present embodiment, an expansion passage 41 is formed on the inlet IN side of the inner surface seal portion 36 formed by the cylindrical body 30 and the ring piece 35 of the impeller 33, and a throttle passage 42 is formed on the outlet EXT side thereof. Further, the labyrinth seal piece 43 is provided on the outlet side thereof. However, the present invention is not limited to this embodiment. For example, as shown in FIG. 11, the wear ring 40 is provided along the circumferential direction of the inner peripheral surface of the cylindrical body 30. The inner surface seal 36 formed between the wear ring 40 and the ring piece 35 of the impeller 33 is detachably attached to the expansion passage 41, the throttle passage 42 and the labyrinth seal piece 43 shown in the ninth embodiment. And a throttle distance ratio L between the expansion passage 41 and the throttle passage 42. ₁ / L ₀ , L ₁ / L ₀ = 2 to 3 may be set.
[0071]
【The invention's effect】
As described above, the submersible pump according to the present invention is a passage means that effectively guides leakage of reactor water to either one of the cylinder housing the impeller and the wear ring detachably attached to the cylinder. In addition, the groove means and the water sealing means are provided in an appropriate combination, and even if solid matter adheres to or accumulates on the passage means, it does not adversely affect the flow of water leakage, so unstable vibration is generated in the pump shaft that supports the impeller. It can be maintained in a stable state without giving.
[Brief description of the drawings]
FIG. 1 is a schematic partial longitudinal sectional view showing a first embodiment of a submersible pump according to the present invention.
FIG. 2 is a cross-sectional plan view taken from the direction of arrows CC in FIG.
FIG. 3 is a schematic partial longitudinal sectional view showing a second embodiment of the submersible pump according to the present invention.
FIG. 4 is a schematic partial longitudinal sectional view showing a third embodiment of the submersible pump according to the present invention.
FIG. 5 is a schematic partial longitudinal sectional view showing a fourth embodiment of the submersible pump according to the present invention.
FIG. 6 is a schematic partial longitudinal sectional view showing a fifth embodiment of the submersible pump according to the present invention.
FIG. 7 is a schematic partial longitudinal sectional view showing a sixth embodiment of the submersible pump according to the present invention.
FIG. 8 is a schematic partial longitudinal sectional view showing a seventh embodiment of the submersible pump according to the present invention.
FIG. 9 is a schematic partial longitudinal sectional view showing an eighth embodiment of the submersible pump according to the present invention.
FIG. 10 is a schematic partial longitudinal sectional view showing a ninth embodiment of the submersible pump according to the present invention.
FIG. 11 is a schematic partial longitudinal sectional view showing a tenth embodiment of a submersible pump according to the present invention.
FIG. 12 is a pressure distribution diagram of the inner surface seal portion obtained in the first embodiment of the submersible pump according to the present invention.
FIG. 13 is a pressure distribution diagram of the inner surface seal portion obtained in the third embodiment of the submersible pump according to the present invention.
FIG. 14 is a pressure distribution diagram of the inner surface seal portion obtained in the fifth embodiment of the submersible pump according to the present invention.
FIG. 15 is a schematic longitudinal sectional view showing a conventional submersible pump.
16 is a schematic view showing the displacement of a pump shaft in a conventional submersible pump, wherein (a) is a plan sectional view cut from the direction of arrows AA in FIG. 15, and (b) is (a) in FIG. Side sectional views cut from the direction of arrows BB are respectively shown.
FIG. 17 is a pressure distribution diagram of an inner surface seal portion that maintains a pump shaft in a stable state in a conventional submersible pump.
FIG. 18 is a pressure distribution diagram of an inner surface seal portion that causes an unstable pump shaft in a conventional submersible pump.
[Explanation of symbols]
1 Furnace body
2 Stud tube
3 Core shroud
4 Pump part
5 Pump drive
6 cylinder
7 Inner seal
8 Wearing
9 Impeller
10 Diffuser
11 Ring pieces
12 Pump shaft
13 Boss
14 Cover
15 Pump casing
16 Can
17 Stator
18 Rotor
19 Wet motor
20 Pump intermediate connector
21 Stretch tube
22 Stretch tube nut
23 Shaft coupling
24 Secondary seal
25 Secondary seal pressurized water pipe
26 Cooling water inlet
27 Cooling water outlet
30 cylinder
31 Pump shaft
32 Boss
33 Impeller
34 Diffuser
35 Ring pieces
36 Inside seal part
37 Inner groove
38 pocket groove
39 Water guide groove
40 Wearing
41 Expansion passage
42 Restricted passage
43 Labyrinth seal pieces

Claims

In a submersible pump including a cylindrical body that houses an impeller supported by a pump shaft, a circumferential direction on the cylindrical side of an inner surface seal portion formed by a ring piece fixed to the outer side of the impeller and an inner surface of the cylindrical body An inner circumferential groove provided along the inner circumferential groove, a water guiding groove that intersects the inner circumferential groove and extends along the axial direction of the pump shaft, and communicates with the water guiding groove and intermittently along the circumferential direction of the cylindrical body. A submersible pump characterized by comprising a pocket groove provided in the water.

In a submersible pump including a cylindrical body that houses an impeller supported by a pump shaft, a wear ring that is detachably attached to the inner surface of the cylindrical body, a ring piece that is fixed to the outer side of the impeller, and an inner surface of the wear ring An inner peripheral groove provided along the circumferential direction on the wear ring side, a water guide groove that intersects the inner peripheral groove and extends along the axial direction of the pump shaft, and the water guide A submersible pump comprising: a pocket groove that communicates with the groove and is provided intermittently along the circumferential direction of the wear ring.

In a submersible pump including a cylindrical body that stores an impeller supported by a pump shaft, an inlet side on the cylindrical side of an inner surface seal portion formed by a ring piece fixed to the outer side of the impeller and an inner surface of the cylindrical body An expansion passage is formed, and communicates with the expansion passage and extends along the axial direction of the pump shaft, and communicates with the water conveyance groove and intermittently along the circumferential direction of the cylindrical body. A submersible pump comprising: a pocket groove provided; and the expanding passage having a configuration in which a cross section of the passage is relatively larger than the water guide groove.

In a submersible pump including a cylindrical body that houses an impeller supported by a pump shaft, a wear ring that is detachably attached to the inner surface of the cylindrical body, a ring piece that is fixed to the outer side of the impeller, and an inner surface of the wear ring A water guide groove extending along the axial direction of the pump shaft on the wear ring side, and a pocket provided intermittently along the circumferential direction of the wear ring. A groove, and an expansion passage formed on the inlet side of the inner surface seal portion formed by the wear ring and the ring piece, and expanding at an end portion on the inlet side. A submersible pump characterized in that it is configured to be relatively larger than a water guide groove.

In water pump with a cylindrical body that houses the supported impeller pump shaft, the inner surface seal portion formed in the inner surface of the ring piece and the cylinder to be fixed to the outside of said impeller, on its inlet side, an inlet An expansion passage that expands at the side end portion is formed, a throttle passage is formed on the outlet side thereof, and the expansion passage is configured to have a relatively larger passage cross section than the inner surface seal portion. Submersible pump characterized by

In a submersible pump including a cylindrical body that stores an impeller supported by a pump shaft, an inner seal portion formed by a ring piece fixed to the outside of the impeller and an inner surface of the cylindrical body in the axial direction of the pump shaft. A water guide groove extending along the water guide groove, a pocket groove provided intermittently along the circumferential direction of the cylindrical body, an expansion passage formed on the inlet side of the inner surface seal portion, and A labyrinth seal piece disposed on the outlet side and provided along the circumferential direction of the cylindrical body, wherein the expansion passage has a configuration in which the passage cross section is relatively larger than the water guide groove. Submersible pump.

In a submersible pump including a cylindrical body that houses an impeller supported by a pump shaft, a wear ring that is detachably attached to the inner surface of the cylindrical body, a ring piece that is fixed to the outer side of the impeller, and an inner surface of the wear ring A water guide groove extending along the axial direction of the pump shaft of the inner surface seal portion formed by, and a pocket groove communicating with the water guide groove and intermittently provided along a circumferential direction of the wear ring, and the wear ring And an expanded passage formed on the inlet side of the inner surface seal portion formed by the ring piece, and a labyrinth seal piece disposed on the outlet side of the inner surface seal portion and provided along the circumferential direction of the wear ring. The submersible pump is characterized in that the expansion passage has a configuration in which a passage cross-section is relatively larger than the water guide groove.

In a submersible pump including a cylindrical body that stores an impeller supported by a pump shaft, an inner surface seal portion formed by a ring piece fixed to the outer side of the impeller and an inner surface of the cylindrical body is expanded to the inlet side. And a labyrinth seal piece disposed along the circumferential direction of the cylindrical body, the expansion passage having a passage cross-section. A submersible pump characterized in that it is configured to be relatively larger than the inner seal portion.

In a submersible pump including a cylindrical body that stores an impeller supported by a pump shaft, a wear ring that is detachably attached to the inner surface of the cylindrical body, a ring piece that is fixed to the outer side of the impeller, and an inner surface of the wear ring In the inner seal portion formed by the above, an expansion passage is formed on the inlet side, and a throttle passage is formed on the outlet side, while being arranged on the outlet side and provided along the circumferential direction of the wear ring. A submersible pump comprising: a labyrinth seal piece, wherein the expansion passage is configured to have a passage cross-section relatively larger than the inner seal portion.

When the distance of the expansion passage to the ring piece of the impeller is L ₁ and the distance of the throttle passage to the ring piece of the impeller is L ₀ , the throttle distance ratio L ₁ / L ₀ is

The submersible pump according to claim 5, 8 or 9, wherein