JP3966655B2

JP3966655B2 - Assembly method for water heater

Info

Publication number: JP3966655B2
Application number: JP29924199A
Authority: JP
Inventors: 島昌二中; 関敏明尾; 田繁桜; 橋正喜高
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1999-10-21
Filing date: 1999-10-21
Publication date: 2007-08-29
Anticipated expiration: 2019-10-21
Also published as: JP2001116205A

Description

【０００１】
【発明の属する技術分野】
本発明は、蒸気タービンを用いる発電プラント等において復水器で得られた凝縮水を加熱して蒸気発生器に供給する給水加熱器に関し、より詳しくは、この給水加熱器の新製取替工事を容易にする給水加熱器の組立方法に関する。
【０００２】
【従来の技術】
従来、火力発電所や原子力発電所等においては発電機を駆動するために蒸気タービンが用いられているが、この蒸気タービンから排出された蒸気は復水器で冷却されて凝縮水となった後、給水加熱器で一旦加熱され、次いで蒸気発生器でさらに加熱されて蒸気となり蒸気タービンに戻される。
【０００３】
上述した給水加熱器の構造を図１３を参照して概説すると、給水加熱器１は、復水器で得られた凝縮水を受け入れる水室２と、蒸気タービンから抽気した高温蒸気がその内部に導入される有底円筒状の本体胴３とを有している。そして、水室２内の給水室４内に導入された凝縮水は、本体胴３内にＵ字状に延在する多数の加熱管５の内部を通過する際に本体胴３内に導入された高温蒸気との熱交換によって加熱された後、水室２の排水室６を介して蒸気発生器に送られる。なお、図１３中に符号７で示したものは多数の加熱管５を保持するための支え板であり、符号８で示す部分は本体胴３の内部に生じたドレンからさらに余熱を回収するためのドレン冷却部、さらに符号９で示したものは給水加熱器１の脚である。
【０００４】
なお、発電所等に据え付けられている既設の給水加熱器を新しい給水加熱器に取り替える工事の際には、従来、既設の給水加熱器を分解して発電所の外に搬出した後、製造工場でその全体を完成させた新しい給水加熱器を発電所内に搬入し、所定の設置場所に据え付けている。
【０００５】
【発明が解決しようとする課題】
ところで、給水加熱器は、その本体胴の外径が約２ｍで全長が１０ｍを越える大きなものであるばかりでなく、その全体重量が４０トン〜１００トンもある非常に重い構造物である。これにより、新しい給水加熱器を発電所内に搬入する際には、幅が３ｍで高さが２ｍかつ長さが１０ｍを越える特別に大きな台車を使用する必要がある。
【０００６】
一方、原子力発電所の場合には、その特有な構造のため、給水加熱器の設置場所や搬入通路等がコンクリートの壁や柱で囲まれている。さらに、その内部には、系統停止に制約があったり放射性物質を内包したりする配管類や、ケーブル類、その他の設備等が縦横に設置されている。
【０００７】
したがって、新しい給水加熱器をそっくりそのまま原子力発電所内に搬入する従来の取替工事では、搬入の際に給水加熱器や台車等と干渉する建物および周囲の設備を改修したり原子力発電所の床を補強したりしなければならず、多大な費用や労力がかかるばかりでなく、取替工事に長い工期を必要としていた。
【０００８】
そこで、本発明の目的は、上述した従来技術が有する問題点を解消し、新旧の給水加熱器の全体を搬出したり搬入したりする必要を無くして、搬入および搬出の際に給水加熱器と干渉する建物や周囲の設備を改修する工事を不要にできるばかりでなく、既に設置されている給水加熱器の本体胴を再利用することにより新しい給水加熱器の製造に要する費用を低減できる、給水加熱器の新しい組立方法を提供することにある。
【０００９】
【課題を解決するための手段】
上記の課題を解決するため、請求項１に記載の給水加熱器の組立方法は、
蒸気タービンが排出した蒸気を冷却して得られた凝縮水を加熱して蒸気発生器に供給する、本体胴および水室を備えた給水加熱器において、既に設置されている古い給水加熱器を分解して本体胴を設置場所に残すとともに、新しく製造した水室を前記設置場所に搬入し、次いで前記設置場所において新しく製造した前記水室に前記本体胴を接合することにより新たな給水加熱器を組み立てる給水加熱器の組立方法であって、
前記本体胴の前記水室に溶接する部分が合金鋼から製造されているときに、前記本体胴の前記水室に溶接する部分に炭素鋼の肉盛り溶接部を予め形成するとともに、前記炭素鋼の肉盛り溶接部を前記水室に溶接することにより前記本体胴および前記水室を一体に溶接し、
炭素鋼の部分の内壁面にステンレス鋼製の肉盛り溶接部を形成して前記炭素鋼の部分を覆うことを特徴とする。
【００１０】
請求項２に記載の給水加熱器の組立方法は、蒸気タービンが排出した蒸気を冷却して得られた凝縮水を加熱して蒸気発生器に供給する、本体胴および水室を備えた給水加熱器において、既に設置されている古い給水加熱器を分解して本体胴を設置場所に残すとともに、新しく製造した水室を前記設置場所に搬入し、次いで前記設置場所において新しく製造した前記水室に前記本体胴を接合することにより新たな給水加熱器を組み立てる給水加熱器の組立方法であって、
前記本体胴の前記水室に溶接する部分が合金鋼から製造されているときに、前記本体胴の前記水室に溶接する部分に炭素鋼の肉盛り溶接部を予め形成するとともに、前記炭素鋼の肉盛り溶接部を前記水室に溶接することにより前記本体胴および前記水室を一体に溶接し、
炭素鋼の部分の内側にステンレス鋼製の筒状部材を配置して、前記炭素鋼の部分を前記本体胴の内側空間から密封することを特徴とする。
【００１１】
請求項３に記載の給水加熱器の組立方法は、蒸気タービンが排出した蒸気を冷却して得られた凝縮水を加熱して蒸気発生器に供給する、本体胴および水室を備えた給水加熱器において、既に設置されている古い給水加熱器を分解して本体胴を設置場所に残すとともに、新しく製造した水室を前記設置場所に搬入し、次いで前記設置場所において新しく製造した前記水室に前記本体胴を接合することにより新たな給水加熱器を組み立てる給水加熱器の組立方法であって、
前記本体胴の前記水室に溶接する部分が合金鋼から製造されているときに、前記本体胴の前記水室に溶接する部分に炭素鋼製の短胴を予め溶接するとともに、
前記炭素鋼製の短胴を前記水室に溶接することにより前記本体胴と前記水室とを一体に溶接し、
炭素鋼の部分の内壁面にステンレス鋼製の肉盛り溶接部を形成して前記炭素鋼の部分を覆うことを特徴とする。
【００１２】
請求項４に記載の給水加熱器の組立方法は、蒸気タービンが排出した蒸気を冷却して得られた凝縮水を加熱して蒸気発生器に供給する、本体胴および水室を備えた給水加熱器において、既に設置されている古い給水加熱器を分解して本体胴を設置場所に残すとともに、新しく製造した水室を前記設置場所に搬入し、次いで前記設置場所において新しく製造した前記水室に前記本体胴を接合することにより新たな給水加熱器を組み立てる給水加熱器の組立方法であって、
前記本体胴の前記水室に溶接する部分が合金鋼から製造されているときに、前記本体胴の前記水室に溶接する部分に炭素鋼製の短胴を予め溶接するとともに、
前記炭素鋼製の短胴を前記水室に溶接することにより前記本体胴と前記水室とを一体に溶接し、
炭素鋼の部分の内側にステンレス鋼製の筒状部材を配置して、前記炭素鋼の部分を前記本体胴の内側空間から密封することを特徴とする。
【００１３】
すなわち、本発明の給水加熱器の組立方法においては、大型で重い給水加熱器の全体を設置場所から搬出したり搬入したりする必要がないから、給水加熱器の搬出および搬入の際に給水加熱器と干渉する建物や周囲の設備を改修する工事が不要となり、給水加熱器の取替工事に要する工期を大幅に短縮し、かつ取替工事に要する費用を大幅に低減することができる。また、既に設置されている給水加熱器の本体胴を再利用するので、新しい給水加熱器の製造に要する資材や労力等を大幅に節約することができる。
【００１４】
ところで、本体胴を水室に溶接する部分がクロムモリブデン鋼のような合金鋼から製造されているときには、本体胴を水室に溶接した後に熱処理が必要となるが、新しい給水加熱器の設置場所においてこのような熱処理を行うことは困難である。
そこで、本体胴の水室に溶接する部分に炭素鋼の肉盛り溶接部を予め形成しておけば、この炭素鋼の肉盛り溶接部と炭素鋼製の水室とを溶接することになり、炭素鋼同士の溶接となるので溶接の後熱処理をほとんど不要にでき、新しい給水加熱器をより一層効率良く組み立てることができる。
同様に、本体胴の水室に溶接する部分に炭素鋼製の短胴を予め溶接しておけば、この炭素鋼製の短胴と炭素鋼製の水室とを溶接することになり、炭素鋼同士の溶接となるので溶接の後熱処理をほとんど不要にでき、新しい給水加熱器をより一層効率良く組み立てることができる。
【００１５】
このとき、給水加熱器の本体胴内に導入される高温蒸気には酸素ガスが含まれるため、炭素鋼が露出していると腐食が進んで減肉するおそれがある。
そこで、本発明のように、炭素鋼の部分である炭素鋼の肉盛り溶接部分若しくは炭素鋼製の短胴の内壁面にステンレス鋼の肉盛り溶接を形成して炭素鋼の部分を覆えば、炭素鋼の部分が高温蒸気に含まれる酸素ガスに接触して腐食し減肉することを防止し、新しい給水加熱器の長寿命化を図ることができる。
同様に、本発明のように、炭素鋼の部分である炭素鋼の肉盛り溶接部若しくは炭素鋼製の短胴の内側にステンレス鋼製の筒状部材を配置し、炭素鋼の部分を本体胴の内側空間から密封すれば、炭素鋼の部分が高温蒸気に含まれる酸素ガスによって腐食して減肉することを防止し、新しい給水加熱器の長寿命化を図ることができる。
【００１６】
請求項５に記載の給水加熱器の組立方法は、請求項１乃至４のいずれか１項に記載の給水加熱器の組立方法において、前記本体胴の内部に装入する機器に前記本体胴の内壁面上を摺動する摺動部材を予め設けておくことを特徴とする。
すなわち、多数の加熱管や加熱管を支持する支え板等の機器に予め摺動部材を設けておけば、これらの機器を本体胴の内部に装入する際に摺動部材が本体胴の内壁面上を摺動し、これらの機器を支持しかつ位置決めするので、新しい給水加熱器をより一層効率良く組み立てることができる。
【００１７】
請求項６に記載の給水加熱器の組立方法は、請求項１乃至５のいずれか１項に記載の給水加熱器の組立方法において、前記水室を製造する際に前記水室に脚当て部材を予め接合しておくとともに、前記設置場所において搬入した前記水室の前記脚当て部材に脚を接合することを特徴とする。
これにより、水室をより小型化できるから、水室を設置場所に搬入する際に建物や周囲の設備と水室とが干渉する可能性をより減少させることができる。
【００１８】
【発明の実施の形態】
以下、本発明に係る給水加熱器の組立方法の各参考例および各実施形態を、図１乃至図１２を参照して詳細に説明する。なお、以下の説明においては、同一の部分には同一の符号を用いてその説明を簡単なものとする。
【００１９】
第１参考例
まず最初に図１を参照し、本発明に係る給水加熱器の組立方法の第１参考例を説明すると、原子力発電所内に設置されていた古い給水加熱器は、その本体胴が水室側の端部において円周方向に溶断される。
そして、水室から分離された本体胴３ａはそのまま設置場所に残されるが、古い給水加熱器の水室や加熱管等はさらに分解されて原子力発電所から搬出される。
これにより、給水加熱器の取替工事に際して、大型で重い構造物である給水加熱器全体を搬出する必要がないから、原子力発電所の建物を改修したり給水加熱器の周囲の設備を除去したりする工事を不要にできる。
【００２０】
一方、工場で新しく製造された水室１２には本体胴の一部を形成する短胴１３を一体に設けるが、その全長Ｌは６メートル以内となるように製造する。
これにより、短胴１３の直径が２メートル程度の場合には新しい水室１２の重量を１０トン以下に収めることができるから、新しい水室１２の搬入に小型の台車を使用することができ、原子力発電所の床を補強する工事を不要にできる。
また、水室１２の全長Ｌを６メートル以内に収めれば、搬入の際に水室１２と原子力発電所の建物や給水加熱器の周囲の設備との干渉を大幅に減少させることができるから、原子力発電所の建物を改修したり給水加熱器の周囲の設備を除去したりする工事を不要にできる。
【００２１】
他方、新しく製造した水室１２の所定の設置場所への搬入が完了すると、設置場所において図示されない加熱管やドレン冷却部等を水室１２に取り付ける。次いで、これらの加熱管やドレン冷却部を本体胴３ａの内部に装入した後、本体胴３ａの端部３ｂと短胴１３の端部１３ａとを突合わせて一体に溶接することにより、新しい給水加熱器１０の組み立てを完了する。
【００２２】
すなわち、本第１参考例の給水加熱器の組立方法によれば、大型で重い給水加熱器の全体を設置場所から搬出したり搬入したりする必要がないから、給水加熱器の搬出および搬入の際に給水加熱器と干渉する建物や周囲の設備を改修する工事が不要となり、給水加熱器の取替工事に要する工期を大幅に短縮し、かつ取替工事に要する費用を大幅に低減することができる。
また、既に設置されている給水加熱器の本体胴を再利用するので、新しい給水加熱器の製造に要する資材や労力等を大幅に節約することができる。
さらに、設置場所に搬入する水室１２をその全長が６メートル以下となるように製造することにより、搬入の際における水室１２と原子力発電所の建物や周囲の設備との干渉が大幅に減少するので、原子力発電所の建物や給水加熱器の周囲の設備を改修する工事を不要とし、給水加熱器の取替工事に要する工期を大幅に短縮し、かつ取替工事に要する費用、さらには取替工事に伴って生じる廃棄物の量を大幅に減少させることができる。
特に原子力発電所の内部には、系統停止に制約があったり放射性物質を内包したりする配管類やケーブル類、その他の設備等が縦横に設置されているため、これらの設備の改修を不要とすることにより、給水加熱器の取替工事に伴う費用を低減し、かつ工事に伴って生じる廃棄物の量を減少させることができる。
【００２３】
第２参考例
次に図２を参照し、本発明に係る給水加熱器の組立方法の第２参考例について説明すると、本第２参考例の組立方法は、古い給水加熱器の本体胴３ａの端部３ｃおよび新しく製造した水室１２側の短胴１３の端部１３ｂを、それぞれ本体胴３ａの軸線に対して水平面垂直な方向からみたときに階段状に形成する点で、上述した第１参考例の組立方法と異なっている。
すなわち、階段状に形成した本体胴３ａの端部３ｃおよび水室１２の端部１３ｂを互いに突合わせた状態で本体胴３ａと短胴１３とを一体に溶接することにより、溶接作業に伴って本体胴３ａおよび短胴１３に発生する変形を減少させることができる。
したがって、本第２参考例の組立方法によれば、溶接を完了した後に通常必要とされる、本体胴３ａおよび短胴１３の断面形状をそれぞれ真円に修正する作業を省くことができるから、新しい給水加熱器２０をより一層効率良く組み立てることができる。
【００２４】
第３参考例
次に図３を参照し、本発明に係る給水加熱器の組立方法の第３参考例について説明すると、本第３参考例の組立方法は、一体に溶接する本体胴３ａの端部３ｂおよび短胴１３の端部１３ａに、予め炭素鋼の肉盛溶接３１，３２をそれぞれ施工しておく点で、上述した第１実施形態の組立方法と異なっている。
【００２５】
すなわち、本体胴３ａや水室１２の短胴１３をクロムモリブデン鋼のような合金鋼から製造する場合には、両者を一体に溶接する際に溶接後の熱処理が必要となるが、新しい給水加熱器３０の設置場所においてこのような熱処理を行うことは困難である。
そこで、本第３参考例の組立方法においては、図４の上半分に示したように、本体胴３ａの端部３ｂおよび短胴１３の端部１３ａに、予め炭素鋼の肉盛溶接３１，３２をそれぞれ施工しておく。
その後、図４の下半分に符号３３で示したように、肉盛溶接３１，３２同士を突合わせ溶接することにより本体胴３ａと短胴１３とを一体に溶接すれば、炭素鋼同士の溶接となるので溶接の後熱処理をほとんど不要にでき、新しい給水加熱器３０をより一層効率良く組み立てることができる。
【００２６】
第４参考例
次に図５を参照し、本発明に係る給水加熱器の組立方法の第４参考例について説明すると、本第４参考例の組立方法は、一体に溶接する本体胴３ａの端部３ｂおよび水室１２の短胴１３の端部１３ａに、炭素鋼製の短胴４１，４２を予め溶接しておく点で、上述した第１参考例の組立方法と異なっている。
【００２７】
すなわち、本体胴３ａや水室１２の短胴１３をクロムモリブデン鋼のような合金鋼から製造する場合には、両者を一体に溶接する際に溶接後の熱処理が必要となるが、新しい給水加熱器４０の設置場所においてこのような熱処理を行うことは困難である。
そこで、本第４参考例の組立方法においては、図６の上半分に示したように、本体胴３ａの端部３ｂに、本体胴３ａと同一外径同一肉厚で軸線方向長さが極めて短い炭素鋼製の短胴４１を溶接部４３で突合わせ溶接する。
同様に、水室１２の短胴１３の端部１３ａに、短胴１３と同一外径同一肉厚で軸線方向長さが極めて短い炭素鋼製の短胴４２を溶接部４４で突合わせ溶接する。
その後、図６の下半分に符号４５で示したように、炭素鋼製の短胴４１，４２同士を突合わせ溶接することにより本体胴３ａおよび水室１２の短胴１３を一体に溶接すれば、炭素鋼同士の溶接となるので溶接の後熱処理をほとんど不要にでき、新しい給水加熱器４０をより一層効率良く組み立てることができる。
【００２８】
第１実施形態
次に図７を参照し、本発明に係る給水加熱器の組立方法の第１実施形態について説明すると、本第１実施形態の組立方法は、炭素鋼の肉盛溶接３１，３２同士を突合わせ溶接した部分の内壁面をステンレス鋼の肉盛り溶接で覆う点で、上述した第３参考例の組立方法と異なっている。
【００２９】
すなわち、給水加熱器の本体胴内に導入される高温蒸気には酸素ガスが含まれているため、炭素鋼が露出していると腐食が進んで減肉するおそれがある。
そこで、本第１実施形態の組立方法では、上述した第３参考例の組立方法による給水加熱器の組み立てが完了した後に、炭素鋼の肉盛溶接３１，３２同士を突合わせ溶接した部分の内壁面にステンレス鋼の肉盛溶接５１を追加し、炭素鋼の肉盛溶接３１，３２同士を突合わせ溶接した部分の内壁面をステンレス鋼の肉盛溶接５１で覆う。
これにより、本体胴３ａおよび水室１２の短胴１３を一体に突合わせ溶接した部分における炭素鋼の肉盛溶接３１，３２が高温蒸気に含まれる酸素ガスによって腐食して減肉することを防止し、新しい給水加熱器５０の長寿命化を図ることができる。
【００３０】
第２実施形態
次に図８を参照し、本発明に係る給水加熱器の組立方法の第２実施形態について説明すると、本第２実施形態の組立方法は、炭素鋼製の短胴４１，４２同士を突合わせ溶接した部分の内壁面をステンレス鋼の肉盛り溶接で覆う点で、上述した第４参考例の組立方法と異なっている。
【００３１】
すなわち、給水加熱器の本体胴内に導入される高温蒸気には酸素ガスが含まれているため、炭素鋼が露出していると腐食が進んで減肉するおそれがある。
そこで、本第２実施形態の組立方法では、上述した第４参考例の組立方法による給水加熱器の組み立てが完了した後に、炭素鋼製の短胴４１，４２の内壁面にステンレス鋼の肉盛溶接６１を追加し、本体胴３ａおよび水室１２の短胴１３を一体に溶接するために設けた炭素鋼製の短胴４１，４２の内壁面をステンレス鋼の肉盛溶接６１で完全に覆う。
これにより、炭素鋼製の短胴４１，４２が高温蒸気に含まれる酸素ガスによって腐食して減肉することを防止し、新しい給水加熱器６０の長寿命化を図ることができる。
【００３２】
第３実施形態
次に図９を参照し、本発明に係る給水加熱器の組立方法の第３実施形態について説明すると、本第３実施形態の組立方法は、本体胴３ａおよび水室１２の短胴１３を一体に溶接した部分の内側にステンレス鋼製のインサート管を配置した点で、上述した第３参考例の組立方法と異なっている。
【００３３】
すなわち、本第３実施形態の組立方法では、上述した第３参考例の組立方法において本体胴３ａの端部３ｂに炭素鋼製の肉盛溶接３１を施工する前若しくは施工した後に、本体胴３ａの内壁面で端部３ｂの近傍部分に、ステンレス鋼製の環状スペーサ７１をその全周にわたって密着させて溶接しておく。
同様に、上述した第３参考例の組立方法において水室１２の短胴１３の端部１３ａに炭素鋼製の肉盛溶接３２を施工する前若しくは施工した後に、短胴１３の内壁面で端部１３ａの近傍部分に、ステンレス鋼製の環状スペーサ７２をその全周にわたって密着させて溶接しておく。
【００３４】
次いで、上述した第３参考例の組立方法と同様に、本体胴３ａの端部３ｂに施工した炭素鋼の肉盛溶接３１と短胴１３の端部１３ａに施工した炭素鋼の肉盛溶接３２とを突合わせ溶接することにより、本体胴３ａと短胴１３とを一体に溶接する。
その後、一対のステンレス鋼製の環状スペーサ７１，７２の内壁面に密着可能な外径を有したステンレス鋼製のインサート管７３を、両環状スペーサ７１，７２に架け渡すように配置するとともに、このインサート管７３の両端部をその全周にわたって環状スペーサ７１，７２の内壁面に溶接する。
すると、本体胴３ａと水室１２の短胴１３とを一体に溶接した部分の内壁面を、一対の環状スペーサ７１，７２およびインサート管７３によって形成される空間７４内に密封することができる。
【００３５】
これにより、本体胴３ａと水室１２の短胴１３とを一体に溶接した部分における炭素鋼の肉盛溶接３１，３２を、新しい給水加熱器７０の内部に導入する高温蒸気に含まれる酸素ガスから隔離することができるから、炭素鋼の肉盛溶接３１，３２が腐食して減肉することを防止し、新しい給水加熱器７０の長寿命化を図ることが出来る。
【００３６】
第４実施形態
次に図１０を参照し、本発明に係る給水加熱器の組立方法の第４実施形態について説明すると、本第４実施形態の組立方法は、本体胴３ａおよび水室１２の短胴１３を一体に溶接した部分の内側にステンレス鋼製のインサート管を配置した点で、上述した第４参考例の組立方法と異なっている。
【００３７】
すなわち、本第４実施形態の組立方法では、上述した第４参考例の組立方法において本体胴３ａの端部３ｂに炭素鋼製の短胴４１を溶接部４３において突合わせ溶接する前若しくは溶接した後に、本体胴３ａの内壁面で端部３ｂの近傍部分に、ステンレス鋼製の環状スペーサ８１をその全周にわたって密着させて溶接しておく。
同様に、上述した第４参考例の組立方法において水室１２の短胴１３の端部１３ａに炭素鋼製の短胴４２を溶接部４４において突合わせ溶接する前若しくは溶接した後に、短胴１３の内壁面で端部１３ａの近傍部分に、ステンレス鋼製の環状スペーサ８２をその全周にわたって密着させて溶接しておく。
【００３８】
次いで、上述した第４参考例の組立方法と同様に、本体胴３ａの端部３ｂに突合わせ溶接した炭素鋼製の短胴４１と、水室１２の短胴１３の端部１３ａに突合わせ溶接した炭素鋼製の短胴４２とを突合わせ溶接することにより、本体胴３ａと水室１２の短胴１３とを一体に溶接する。
その後、一対のステンレス鋼製の環状スペーサ８１，８２の内壁面に密着可能な外径を有したステンレス鋼製のインサート管８３を、両環状スペーサ８１，８２に架け渡すように配置するとともに、このインサート管８３の両端部をその全周にわたって環状スペーサ８１，８２の内壁面に溶接する。
すると、本体胴３ａと水室１２の短胴１３とを一体に溶接した部分の内壁面を、一対の環状スペーサ８１，８２およびインサート管８３によって形成される空間８４内に密封することができる。
【００３９】
これにより、本体胴３ａと水室１２の短胴１３とを一体に溶接した部分における炭素鋼製の短胴４１，４２を、新しい給水加熱器８０の内部に導入する高温蒸気に含まれる酸素ガスから隔離することができるから、炭素鋼製の短胴４１，４２が腐食して減肉することを防止し、新しい給水加熱器８０の長寿命化を図ることが出来る。
【００４０】
第５参考例
次に図１１を参照し、本発明に係る給水加熱器の組立方法の第５参考例について説明すると、本第５参考例の組立方法においては、水室１２から本体胴３ａの内部に延びる多数の加熱管５を支持する支え板７の下部に、ドレン冷却部８を除いてそり９１を設ける。
【００４１】
前記そり９１は、図１１示したように、多数の加熱管５を本体胴３ａの内部に装入する際に本体胴３ａの内壁面上を摺動し、加熱管５および支え板７の本体胴３ａ内への装入を容易にするとともに、装入完了後には加熱管５および支え板７を本体胴３ａに対して正確に芯出しする。これにより、本第５参考例の組立方法によれば、新しい給水加熱器９０をより一層効率良く組み立てることができる。
【００４２】
第６参考例
次に図１２を参照し、本発明に係る給水加熱器の組立方法の第６参考例について説明すると、本第６参考例の組立方法においては、水室１２の外壁面に脚当て板１０１を溶接した状態で水室１２を設置場所に搬入した後、設置場所において脚当て板１０１に脚１０２を溶接する。これにより、設置場所に搬入する水室１２をより小型化できるから、新しい給水加熱器１００を設置する建物や周囲の設備と水室１２との干渉をなくすことができる。したがって、本第６参考例の組立方法によれば、水室１２を搬入するために建物を改修したり周囲の設備を除去したりする必要がなく、給水加熱器の取替工事をより一層効率良く行うことができる。
【００４３】
【発明の効果】
以上の説明から明らかなように、本発明の給水加熱器の組立方法は、既に設置されている古い給水加熱器を分解してその本体胴を再利用するとともに、新しく製造した水室等を設置場所に搬入し、設置場所において両者を一体に溶接して組み立てるものである。
このとき、本発明においては、炭素鋼の部分同士を互いに溶接した部分を、ステンレス鋼の肉盛り溶接若しくはステンレス鋼製の筒状部材で覆うので、本体胴の内部に導入される高温蒸気に含まれる酸素によって炭素鋼の部分が腐食し減肉することを防止できる。
【図面の簡単な説明】
【図１】本発明に係る第１参考例の給水加熱器の組立方法を示す側面図。
【図２】本発明に係る第２参考例の給水加熱器の組立方法を示す側面図。
【図３】本発明に係る第３参考例の給水加熱器の組立方法を示す側面図。
【図４】図３中に示したＩＶ−ＩＶ破断線に沿った断面図。
【図５】本発明に係る第４参考例の給水加熱器の組立方法を示す側面図。
【図６】図５中に示したＶＩ−ＶＩ破断線に沿った断面図。
【図７】本発明に係る第１実施形態の給水加熱器の組立方法を示す側面図。
【図８】本発明に係る第２実施形態の給水加熱器の組立方法を示す側面図。
【図９】本発明に係る第３実施形態の給水加熱器の組立方法を示す側面図。
【図１０】本発明に係る第４実施形態の給水加熱器の組立方法を示す側面図。
【図１１】本発明に係る第５参考例の給水加熱器の組立方法を示す側面図。
【図１２】本発明に係る第６参考例の給水加熱器の組立方法を示す側面図。
【図１３】給水加熱器の全体構造を示す要部破断側面図。
【符号の説明】
１給水加熱器
２水室
３本体胴
３ａ，３ｂ，３ｃ端部
４給水室
５加熱管
６排水室
７支え板
８ドレン冷却部
９脚
１０第１参考例の給水加熱器
１２水室
１３短胴
１３ａ端部
２０第２参考例の給水加熱器
３０第３参考例の給水加熱器
３１，３２炭素鋼の肉盛溶接
３３突合わせ溶接部
４０第４参考例の給水加熱器
４１，４２炭素鋼製の短胴
４３，４４突合わせ溶接部
４５突合わせ溶接部
５０第１実施形態の給水加熱器
５１ステンレス鋼の肉盛り溶接
６０第２実施形態の給水加熱器
６１ステンレス鋼の肉盛り溶接部
７０第３実施形態の給水加熱器
７１，７２ステンレス鋼製の環状スペーサ
７３ステンレス鋼製のインサート管
８０第４実施形態の給水加熱器
８１，８２ステンレス鋼製の環状スペーサ
８３ステンレス鋼製のインサート管
９０第５参考例の給水加熱器
９１そり
１００第６参考例の給水加熱器
１０１脚当て板
１０２脚[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a feed water heater for heating condensed water obtained by a condenser in a power plant using a steam turbine and supplying the steam generator, and more specifically, a new replacement work for the feed water heater. The present invention relates to a method for assembling a water heater.
[0002]
[Prior art]
  Conventionally, steam turbines are used to drive generators at thermal power plants and nuclear power plants, but the steam discharged from the steam turbine is cooled by a condenser to become condensed water. The water is once heated by the feed water heater and then further heated by the steam generator to become steam and returned to the steam turbine.
[0003]
  The structure of the feed water heater described above will be outlined with reference to FIG. 13. The feed water heater 1 includes a water chamber 2 that receives the condensed water obtained by the condenser, and high-temperature steam extracted from the steam turbine inside. It has a bottomed cylindrical body 3 to be introduced. Then, the condensed water introduced into the water supply chamber 4 in the water chamber 2 is introduced into the main body barrel 3 when passing through the insides of a large number of heating pipes 5 extending in a U shape within the main body barrel 3. After being heated by heat exchange with the high-temperature steam, it is sent to the steam generator via the drainage chamber 6 of the water chamber 2. The reference numeral 7 in FIG. 13 is a support plate for holding a large number of heating tubes 5, and the portion indicated by reference numeral 8 is for recovering further heat from the drain generated inside the main body 3. The drain cooling part of FIG. 1 and the reference numeral 9 are legs of the feed water heater 1.
[0004]
  When replacing existing water heaters installed at power plants with new water heaters, the existing water heaters have been disassembled and transported outside the power plant before being manufactured at the factory. A new feed water heater, which has been completed as a whole, is carried into the power plant and installed at a predetermined location.
[0005]
[Problems to be solved by the invention]
  By the way, the feed water heater is not only a large body having an outer diameter of about 2 m and a total length exceeding 10 m, but also a very heavy structure having an overall weight of 40 to 100 tons. Thus, when a new feed water heater is carried into the power plant, it is necessary to use a specially large cart having a width of 3 m, a height of 2 m and a length exceeding 10 m.
[0006]
  On the other hand, in the case of a nuclear power plant, because of its unique structure, the installation location of the feed water heater and the carry-in passage are surrounded by concrete walls and pillars. In addition, piping, cables, and other equipment that have restrictions on system shutdown or contain radioactive materials are installed vertically and horizontally.
[0007]
  Therefore, in the conventional replacement work in which a new water heater is carried into the nuclear power plant as it is, the building and surrounding facilities that interfere with the water heater, the carriage, etc. at the time of loading are repaired or the floor of the nuclear power plant is installed. In addition to enormous costs and labor, the replacement work required a long construction period.
[0008]
  Therefore, an object of the present invention is to eliminate the problems of the above-described conventional technology, eliminate the need to carry out and carry in the whole of the old and new feed water heaters, Water supply that not only eliminates the need to renovate interfering buildings and surrounding facilities, but also reduces the cost of manufacturing new water heaters by reusing the main body of the existing water heater. It is to provide a new method for assembling a heater.
[0009]
[Means for Solving the Problems]
  In order to solve the above-mentioned problem, an assembly method of the feed water heater according to claim 1 is:
  A water heater with a main body and a water chamber that heats the condensed water obtained by cooling the steam discharged from the steam turbine and supplies it to the steam generatorInAn old feed water heater that has already been installed is disassembled to leave the main body cylinder at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body cylinder is inserted into the newly manufactured water chamber at the installation location. Assembling method of feed water heater by assembling a new feed water heater by joiningBecause
  When the portion of the main body to be welded to the water chamber is manufactured from alloy steel, a carbon steel build-up weld is formed in advance on the portion of the main body to be welded to the water chamber, and the carbon steel Welding the body trunk and the water chamber together by welding the build-up welded portion to the water chamber,
  A build-up weld made of stainless steel is formed on the inner wall surface of the carbon steel portion to cover the carbon steel portionIt is characterized by that.
[0010]
  The method for assembling a feed water heater according to claim 2 comprises heating a condensed water obtained by cooling steam discharged from a steam turbine and supplying the steam generator with a main body barrel and a water chamber. vesselInAn old feed water heater that has already been installed is disassembled to leave the main body cylinder at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body cylinder is inserted into the newly manufactured water chamber at the installation location. Assembling method of feed water heater by assembling a new feed water heater by joiningBecause
  When the portion of the main body to be welded to the water chamber is manufactured from alloy steel, a carbon steel build-up weld is formed in advance on the portion of the main body to be welded to the water chamber, and the carbon steel Welding the body trunk and the water chamber together by welding the build-up welded portion to the water chamber,
  A cylindrical member made of stainless steel is disposed inside the carbon steel portion, and the carbon steel portion is sealed from the inner space of the body trunk.It is characterized by that.
[0011]
  The method for assembling a feed water heater according to claim 3 is a feed water heating system comprising a main body and a water chamber for heating condensed water obtained by cooling steam discharged from a steam turbine and supplying the condensed water to a steam generator. vesselInAn old feed water heater that has already been installed is disassembled to leave the main body cylinder at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body cylinder is inserted into the newly manufactured water chamber at the installation location. Assembling method of feed water heater by assembling a new feed water heater by joiningBecause
  When the portion to be welded to the water chamber of the main body is manufactured from alloy steel, a carbon steel short drum is pre-welded to the portion to be welded to the water chamber of the main body,
By welding the carbon steel short drum to the water chamber, the main body drum and the water chamber are integrally welded,
  A build-up weld made of stainless steel is formed on the inner wall surface of the carbon steel portion to cover the carbon steel portionIt is characterized by that.
[0012]
  The method for assembling a feed water heater according to claim 4 is a feed water heating system comprising a main body and a water chamber for heating condensed water obtained by cooling steam discharged from a steam turbine and supplying the condensed water to a steam generator. vesselIn LeaveAn old feed water heater that has already been installed is disassembled to leave the main body cylinder at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body cylinder is inserted into the newly manufactured water chamber at the installation location. Assembling method of feed water heater by assembling a new feed water heater by joiningBecause
  When the portion to be welded to the water chamber of the main body is manufactured from alloy steel, a carbon steel short drum is pre-welded to the portion to be welded to the water chamber of the main body,
  By welding the carbon steel short drum to the water chamber, the main body drum and the water chamber are integrally welded,
  A cylindrical member made of stainless steel is disposed inside the carbon steel portion, and the carbon steel portion is sealed from the inner space of the body trunk.It is characterized by that.
[0013]
  That is, in the assembling method of the feed water heater of the present invention.InSince it is not necessary to carry out and carry in the entire large and heavy feedwater heater from the installation site, there is no work to repair buildings and surrounding equipment that interfere with the feedwater heater when carrying out and carrying in the feedwater heater. It becomes unnecessary, the construction period required for the replacement work of the feed water heater can be greatly shortened, and the cost required for the replacement work can be greatly reduced. Moreover, since the main body drum of the feed water heater that has already been installed is reused, the materials, labor, and the like required for manufacturing a new feed water heater can be greatly saved.
[0014]
  by the way,When the part where the main body is welded to the water chamber is manufactured from alloy steel such as chromium molybdenum steel, heat treatment is required after the main body is welded to the water chamber. It is difficult to perform such heat treatment.
  Therefore, if a carbon steel build-up weld is formed in advance in the part to be welded to the water chamber of the main body, this carbon steel build-up weld and the carbon steel water chamber will be welded. Since the carbon steel is welded to each other, almost no post-weld heat treatment is required, and a new water heater can be assembled more efficiently.
  Similarly,If a carbon steel short drum is welded in advance to the part to be welded to the water chamber of the main body shell, this carbon steel short drum and the carbon steel water chamber will be welded. Since it becomes welding, almost no heat treatment after welding is required, and a new feed water heater can be assembled more efficiently.
[0015]
  At this time,Since the high-temperature steam introduced into the main body of the feed water heater contains oxygen gas, if the carbon steel is exposed, there is a possibility that corrosion proceeds and the thickness is reduced.
  Therefore,Like the present invention,If carbon steel build-up welding is formed on the inner wall of a carbon steel or carbon steel short cylinder and the carbon steel part is covered to cover the carbon steel part, the carbon steel part becomes high-temperature steam. It is possible to prevent corrosion and thinning due to contact with oxygen gas contained, and to extend the life of a new feed water heater.
  Similarly, as in the present invention,If a cylindrical member made of stainless steel is placed inside the carbon steel build-up weld or carbon steel short cylinder, and the carbon steel part is sealed from the inner space of the main body cylinder, carbon It is possible to prevent the steel portion from being corroded and thinned by oxygen gas contained in the high-temperature steam, and to extend the life of a new feed water heater.
[0016]
  Claim5The method of assembling the feed water heater according to claim 14Either1 itemIn the assembling method of the feed water heater according to claim 1, a sliding member that slides on the inner wall surface of the main body cylinder is provided in advance in a device to be inserted into the main body cylinder.
  That is, if a sliding member is provided in advance on a device such as a large number of heating tubes and supporting plates that support the heating tube, the sliding member is placed inside the main body cylinder when these devices are inserted into the main body cylinder. Since it slides on the wall and supports and positions these devices, a new feed water heater can be more efficiently assembled.
[0017]
  Claim6The method of assembling the feed water heater according to claim 15Either1 itemIn the method for assembling the feed water heater according to claim 1, a leg rest member is previously joined to the water chamber when the water chamber is manufactured, and a leg is attached to the leg rest member of the water chamber carried in at the installation location. It is characterized by joining.
  Thereby, since a water chamber can be reduced in size, when a water chamber is carried in to an installation place, possibility that a building or the surrounding facility and a water chamber will interfere can be reduced more.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the method for assembling the feed water heater according to the present invention will be described.Each reference example and eachThe embodiment will be described in detail with reference to FIGS. In the following description, the same parts are denoted by the same reference numerals, and the description will be simplified.
[0019]
  First reference example
  First, referring to FIG. 1, the method of assembling the feed water heater according to the present invention will be described.First reference exampleIn the old feed water heater installed in the nuclear power plant, its main body is melted in the circumferential direction at the end of the water chamber.
  The main body trunk 3a separated from the water chamber is left as it is at the installation location, but the water chamber and the heating pipe of the old feed water heater are further disassembled and carried out of the nuclear power plant.
  As a result, there is no need to carry out the entire large and heavy feedwater heater when replacing the feedwater heater.Therefore, the building of the nuclear power plant has been refurbished and the equipment around the feedwater heater has been removed. Can be eliminated.
[0020]
  On the other hand, the water chamber 12 newly manufactured in the factory is integrally provided with a short body 13 which forms a part of the main body body, and the total length L is manufactured to be within 6 meters.
  Thereby, since the weight of the new water chamber 12 can be stored in 10 tons or less when the diameter of the short trunk 13 is about 2 meters, a small cart can be used for carrying in the new water chamber 12, Work to reinforce the floor of a nuclear power plant can be eliminated.
  Also, if the total length L of the water chamber 12 is kept within 6 meters, interference between the water chamber 12 and the facilities around the nuclear power plant and the water heater can be significantly reduced during loading. This eliminates the need to renovate the building of the nuclear power plant or remove the equipment around the water heater.
[0021]
  On the other hand, when the newly manufactured water chamber 12 is brought into the predetermined installation location, a heating tube, a drain cooling unit, etc. (not shown) are attached to the water chamber 12 at the installation location. Then, after these heating tubes and drain cooling parts are inserted into the main body cylinder 3a, the end part 3b of the main body cylinder 3a and the end part 13a of the short cylinder 13 are brought into contact with each other and welded together. The assembly of the feed water heater 10 is completed.
[0022]
  Ie bookFirst reference exampleAccording to the method for assembling the feed water heater, there is no need to carry out and carry in the entire large and heavy feed water heater from the installation location, so it interferes with the feed water heater when carrying out and carrying in the feed water heater. This eliminates the need to renovate the building and surrounding facilities, greatly shorten the construction period required for the replacement of the feed water heater, and greatly reduce the cost required for the replacement.
  Moreover, since the main body drum of the feed water heater that has already been installed is reused, the materials, labor, and the like required for manufacturing a new feed water heater can be greatly saved.
  Furthermore, by manufacturing the water chamber 12 to be transported to the installation site so that its total length is 6 meters or less, interference between the water chamber 12 and the building of the nuclear power plant and surrounding facilities during the transport is greatly reduced. This eliminates the need to renovate the facilities around the nuclear power plant building and the feed water heater, significantly shortens the work period required for the replacement of the feed water heater, and the cost required for the replacement work. The amount of waste generated by replacement work can be greatly reduced.
  In particular, the nuclear power plant has piping, cables, and other equipment that are restricted in terms of system shutdown and contain radioactive materials, and are installed vertically and horizontally. By doing so, it is possible to reduce the cost associated with the replacement work of the feed water heater and to reduce the amount of waste generated with the work.
[0023]
  Second reference example
  Next, referring to FIG. 2, the method of assembling the feed water heater according to the present invention will be described.Second reference exampleExplain about the bookSecond reference exampleIn the assembling method, the end portion 3c of the main body cylinder 3a of the old feed water heater and the end portion 13b of the short cylinder 13 on the side of the newly produced water chamber 12 were respectively viewed from the direction perpendicular to the axis of the main body cylinder 3a. The point mentioned above, sometimes in the form of a staircaseFirst reference exampleThis is different from the assembly method.
  That is, with the welding operation, the main body cylinder 3a and the short body 13 are integrally welded with the end 3c of the main body cylinder 3a and the end 13b of the water chamber 12 formed in a staircase shape facing each other. The deformation generated in the main body cylinder 3a and the short cylinder 13 can be reduced.
  So bookSecond reference exampleAccording to this assembly method, it is possible to omit the work of correcting the cross-sectional shapes of the main body cylinder 3a and the short cylinder 13 to be perfect circles, which is normally required after the welding is completed. It can be assembled more efficiently.
[0024]
  Third reference example
  Next, referring to FIG. 3, the method of assembling the feed water heater according to the present invention will be described.Third reference exampleExplain about the bookThird reference exampleThis assembly method is the first implementation described above in that carbon steel build-up welds 31 and 32 are respectively preliminarily applied to the end 3b of the main body 3a and the end 13a of the short body 13 to be integrally welded. It is different from the form assembly method.
[0025]
  That is, when the main body body 3a and the short body 13 of the water chamber 12 are manufactured from alloy steel such as chrome molybdenum steel, heat treatment after welding is required when both are welded together. It is difficult to perform such heat treatment at the place where the vessel 30 is installed.
  So bookThird reference exampleIn this assembly method, as shown in the upper half of FIG. 4, carbon steel build-up welds 31 and 32 are previously applied to the end 3 b of the main body cylinder 3 a and the end 13 a of the short cylinder 13, respectively. .
  Thereafter, as indicated by reference numeral 33 in the lower half of FIG. 4, if the body barrel 3 a and the short barrel 13 are welded together by butt welding the build-up welds 31, 32, the carbon steels are welded together. Therefore, the heat treatment after welding can be made almost unnecessary, and the new feed water heater 30 can be assembled more efficiently.
[0026]
  Fourth reference example
  Next, referring to FIG. 5, the method of assembling the feed water heater according to the present invention will be described.Fourth reference exampleExplain about the bookFourth reference exampleThis method of assembly is described above in that carbon steel short cylinders 41 and 42 are pre-welded to the end 3b of the main body cylinder 3a and the end 13a of the short cylinder 13 of the water chamber 12 which are integrally welded.First reference exampleThis is different from the assembly method.
[0027]
  That is, when the main body body 3a and the short body 13 of the water chamber 12 are manufactured from alloy steel such as chrome molybdenum steel, heat treatment after welding is required when both are welded together. It is difficult to perform such heat treatment at the place where the vessel 40 is installed.
  So bookFourth reference exampleIn the assembling method of FIG. 6, as shown in the upper half of FIG. 6, a short body made of carbon steel is formed on the end 3b of the main body cylinder 3a with the same outer diameter and the same wall thickness as the main body cylinder 3a. 41 is butt welded at the weld 43.
  Similarly, a short drum 42 made of carbon steel having the same outer diameter and the same wall thickness as the short drum 13 and an extremely short axial length is butt-welded to the end 13 a of the short drum 13 of the water chamber 12 by a welding portion 44. .
  Thereafter, as indicated by reference numeral 45 in the lower half of FIG. 6, the main body body 3 a and the short body 13 of the water chamber 12 are welded together by butt welding the short bodies 41, 42 made of carbon steel. Since carbon steel is welded to each other, post-welding heat treatment can be made almost unnecessary, and a new water heater 40 can be assembled more efficiently.
[0028]
  First1Embodiment
  Next, referring to FIG. 7, a first method of assembling the feed water heater according to the present invention is described.1The embodiment will be described.1The assembly method of the embodiment has been described above in that the inner wall surface of the portion where the welds 31 and 32 of the carbon steel are butt-welded to each other is covered with the overlay welding of the stainless steel.Third reference exampleThis is different from the assembly method.
[0029]
  That is, since the high-temperature steam introduced into the main body of the feed water heater contains oxygen gas, if the carbon steel is exposed, there is a possibility that corrosion proceeds and the thickness is reduced.
  So this book1In the assembly method of the embodiment, the above-described method is used.Third reference exampleAfter the assembly of the feed water heater by the assembling method is completed, the overlay welding 51 of stainless steel is added to the inner wall surface of the portion where the welds 31 and 32 of the carbon steel are butt-welded to each other, and the overlaying of the carbon steel is performed. The inner wall surface of the portion where the welds 31 and 32 are butt-welded is covered with a stainless steel overlay weld 51.
  This prevents the build-up welds 31 and 32 of the carbon steel at the portion where the main body body 3a and the short body 13 of the water chamber 12 are integrally butt welded from being corroded by the oxygen gas contained in the high-temperature steam. In addition, the life of the new feed water heater 50 can be extended.
[0030]
  First2Embodiment
  Next, referring to FIG. 8, a first method of assembling the feed water heater according to the present invention is described.2The embodiment will be described.2The assembly method of the embodiment is described above in that the inner wall surface of the portion where the short drums 41 and 42 made of carbon steel are butt welded is covered with the overlay welding of stainless steel.Fourth reference exampleThis is different from the assembly method.
[0031]
  That is, since the high-temperature steam introduced into the main body of the feed water heater contains oxygen gas, if the carbon steel is exposed, there is a possibility that corrosion proceeds and the thickness is reduced.
  So this book2In the assembly method of the embodiment, the above-described method is used.Fourth reference exampleAfter the assembly of the feed water heater by the assembling method is completed, the overlay welding 61 of stainless steel is added to the inner wall surface of the short drums 41 and 42 made of carbon steel, and the main drum 3a and the short drum 13 of the water chamber 12 are connected. The inner wall surfaces of the carbon steel short drums 41 and 42 provided for welding together are completely covered with the overlay welding 61 of stainless steel.
  Thereby, it is possible to prevent the carbon steel short bodies 41 and 42 from being corroded and thinned by oxygen gas contained in the high-temperature steam, and to extend the life of the new feed water heater 60.
[0032]
  First3Embodiment
  Next, referring to FIG. 9, a first method of assembling the feed water heater according to the present invention is described.3The embodiment will be described.3The assembly method of the embodiment has been described above in that a stainless steel insert pipe is disposed inside a portion where the main body body 3a and the short body 13 of the water chamber 12 are integrally welded.Third reference exampleThis is different from the assembly method.
[0033]
  That is, this3In the assembly method of the embodiment, the above-described method is used.Third reference exampleIn the assembling method, before or after the carbon steel overlay welding 31 is applied to the end portion 3b of the main body cylinder 3a, an annular spacer made of stainless steel is provided in the vicinity of the end portion 3b on the inner wall surface of the main body cylinder 3a. 71 is welded in close contact with the entire circumference.
  Similarly, as mentioned aboveThird reference exampleIn the assembling method, before or after the build-up welding 32 made of carbon steel is applied to the end portion 13a of the short drum 13 of the water chamber 12, the inner wall surface of the short drum 13 is provided with stainless steel in the vicinity of the end portion 13a. A ring-shaped spacer 72 made of a metal is intimately welded over the entire circumference.
[0034]
  Then mentioned aboveThird reference exampleIn the same manner as in the above assembly method, the carbon steel overlay welding 31 applied to the end 3b of the main body cylinder 3a and the carbon steel overlay welding 32 applied to the end 13a of the short cylinder 13 are butt welded. The main body cylinder 3a and the short cylinder 13 are welded together.
  Thereafter, a stainless steel insert pipe 73 having an outer diameter capable of being in close contact with the inner wall surfaces of the pair of stainless steel annular spacers 71 and 72 is disposed so as to span the annular spacers 71 and 72. Both ends of the insert pipe 73 are welded to the inner wall surfaces of the annular spacers 71 and 72 over the entire circumference.
  Then, the inner wall surface of the portion where the main body body 3 a and the short body 13 of the water chamber 12 are integrally welded can be sealed in the space 74 formed by the pair of annular spacers 71 and 72 and the insert pipe 73.
[0035]
  Thereby, the oxygen gas contained in the high-temperature steam that introduces the carbon steel build-up welds 31 and 32 in the portion where the main body body 3 a and the short body 13 of the water chamber 12 are integrally welded into the new feed water heater 70. Therefore, it is possible to prevent the build-up welds 31 and 32 of the carbon steel from being corroded and thinned, and to extend the life of the new feed water heater 70.
[0036]
  First4Embodiment
  Next, referring to FIG. 10, a first method of assembling the feed water heater according to the present invention is described.4The embodiment will be described.4The assembly method of the embodiment has been described above in that a stainless steel insert pipe is disposed inside a portion where the main body body 3a and the short body 13 of the water chamber 12 are integrally welded.Fourth reference exampleThis is different from the assembly method.
[0037]
  That is, this4In the assembly method of the embodiment, the above-described method is used.Fourth reference exampleIn the assembling method, before or after the short barrel 41 made of carbon steel is butt welded to the end portion 3b of the main body cylinder 3a at the welded portion 43, the inner wall surface of the main body cylinder 3a is made of stainless steel near the end portion 3b. A steel annular spacer 81 is in close contact with the entire circumference and welded.
  Similarly, as mentioned aboveFourth reference exampleIn the assembling method, before or after butt welding the carbon steel short drum 42 to the end 13a of the short drum 13 of the water chamber 12 at the weld 44, the inner wall surface of the short drum 13 is near the end 13a. A stainless steel annular spacer 82 is in close contact with the entire circumference and welded.
[0038]
  Then mentioned aboveFourth reference exampleThe carbon steel short cylinder 41 butt welded to the end 3b of the main body cylinder 3a and the carbon steel short cylinder butt welded to the end 13a of the short cylinder 13 of the water chamber 12 in the same manner as the assembling method of FIG. The main body barrel 3a and the short drum 13 of the water chamber 12 are integrally welded by butt welding with 42.
  Thereafter, an insert pipe 83 made of stainless steel having an outer diameter that can be brought into close contact with the inner wall surfaces of the pair of stainless steel annular spacers 81 and 82 is arranged so as to span the annular spacers 81 and 82. Both ends of the insert pipe 83 are welded to the inner wall surfaces of the annular spacers 81 and 82 over the entire circumference.
  Then, the inner wall surface of the portion where the main body body 3 a and the short body 13 of the water chamber 12 are integrally welded can be sealed in the space 84 formed by the pair of annular spacers 81 and 82 and the insert pipe 83.
[0039]
  As a result, the oxygen gas contained in the high-temperature steam that introduces the carbon steel short cylinders 41 and 42 in the portion where the main body cylinder 3 a and the short cylinder 13 of the water chamber 12 are integrally welded into the new feed water heater 80. Therefore, it is possible to prevent the carbon steel short drums 41 and 42 from corroding and thinning, and to extend the life of the new feed water heater 80.
[0040]
  5th reference example
  Next, referring to FIG. 11, the method of assembling the feed water heater according to the present invention will be described.5th reference exampleExplain about the book5th reference exampleIn this assembling method, a sled 91 is provided under the support plate 7 that supports a large number of heating tubes 5 extending from the water chamber 12 to the inside of the main body 3a, except for the drain cooling section 8.
[0041]
  As shown in FIG. 11, the sled 91 slides on the inner wall surface of the main body cylinder 3a when the large number of heating pipes 5 are inserted into the main body cylinder 3a. In addition to facilitating the insertion into the cylinder 3a, the heating tube 5 and the support plate 7 are accurately centered with respect to the main body cylinder 3a after the completion of the insertion. This makes the book5th reference exampleAccording to this assembly method, the new feed water heater 90 can be assembled more efficiently.
[0042]
  Sixth reference example
  Next, referring to FIG. 12, the method for assembling the feed water heater according to the present invention will be described.Sixth reference exampleExplain about the bookSixth reference exampleIn the assembling method, after the water chamber 12 is carried into the installation place with the leg rest plate 101 welded to the outer wall surface of the water chamber 12, the legs 102 are welded to the leg rest plate 101 at the installation location. Thereby, since the water chamber 12 carried in to an installation place can be reduced in size, the interference with the water chamber 12 with the building and surrounding facilities which install the new feed water heater 100 can be eliminated. So bookSixth reference exampleAccording to this assembling method, it is not necessary to renovate the building or remove the surrounding equipment in order to carry in the water chamber 12, and the replacement work of the water heater can be performed more efficiently.
[0043]
【The invention's effect】
  As is clear from the above description, the method for assembling the feed water heater of the present invention is to disassemble an old feed water heater that has already been installed and reuse its main body, and install a newly manufactured water chamber or the like. It is carried into a place and assembled by welding them together at the place of installation.
  At this time, in the present invention,Since the parts where the carbon steel parts are welded together are covered with a stainless steel build-up weld or a stainless steel tubular member, the carbon steel parts are formed by the oxygen contained in the high-temperature steam introduced into the body barrel. Corrosion and thinning can be prevented.
[Brief description of the drawings]
FIG. 1 relates to the present invention.First reference exampleThe side view which shows the assembly method of the water heater of this.
FIG. 2 relates to the present invention.Second reference exampleThe side view which shows the assembly method of the water heater of this.
FIG. 3 relates to the present invention.Third reference exampleThe side view which shows the assembly method of the water heater of this.
4 is a cross-sectional view taken along the IV-IV break line shown in FIG. 3;
FIG. 5 relates to the present invention.Fourth reference exampleThe side view which shows the assembly method of the water heater of this.
6 is a cross-sectional view taken along the VI-VI break line shown in FIG.
FIG. 7 is a diagram according to the present invention1The side view which shows the assembly method of the feed water heater of embodiment.
FIG. 8 is a diagram according to the present invention2The side view which shows the assembly method of the feed water heater of embodiment.
FIG. 9 is a diagram according to the present invention3The side view which shows the assembly method of the feed water heater of embodiment.
FIG. 10 is a diagram according to the present invention4The side view which shows the assembly method of the feed water heater of embodiment.
FIG. 11 is related to the present invention.5th reference exampleThe side view which shows the assembly method of the water heater of this.
FIG. 12 is related to the present invention.Sixth reference exampleThe side view which shows the assembly method of the water heater of this.
FIG. 13 is a cutaway side view of the main part showing the entire structure of the feed water heater.
[Explanation of symbols]
1 Water heater
2 water chamber
3 Body
3a, 3b, 3c end
4 Water supply room
5 Heating tube
6 Drainage chamber
7 Support plate
8 Drain cooling section
9 legs
10First reference exampleWater heater
12 Water chamber
13 Short torso
13a end
20Second reference exampleWater heater
30Third reference exampleWater heater
31,32 Overlay welding of carbon steel
33 Butt weld
40Fourth reference exampleWater heater
41, 42 short body made of carbon steel
43, 44 Butt weld
45 Butt weld
50th1Feed water heater of embodiment
51 Overlay welding of stainless steel
60th2Feed water heater of embodiment
61 Stainless steel overlay weld
70th3Feed water heater of embodiment
71,72 Annular spacer made of stainless steel
73 Stainless steel insert tube
80th4Feed water heater of embodiment
81,82 Stainless steel annular spacer
83 Stainless steel insert tube
905th reference exampleWater heater
91 Sled
100Sixth reference exampleWater heater
101 Leg plate
102 legs

Claims

Supplied to the steam generator to heat the condensed water obtained steam steam turbine is discharged by cooling, the feed water heater with a body trunk and the water chamber, decomposing already old feed water heater is installed The main body barrel is left at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body barrel is joined to the newly manufactured water chamber at the installation location, thereby providing a new water heater. An assembly method for a water heater to be assembled ,
When the portion of the main body to be welded to the water chamber is manufactured from alloy steel, a carbon steel build-up weld is formed in advance on the portion of the main body to be welded to the water chamber, and the carbon steel Welding the body trunk and the water chamber together by welding the build-up welded portion to the water chamber,
A method for assembling a feed water heater, comprising forming a build-up weld made of stainless steel on an inner wall surface of a carbon steel portion to cover the carbon steel portion .

Supplied to the steam generator to heat the condensed water obtained steam steam turbine is discharged by cooling, the feed water heater with a body trunk and the water chamber, decomposing already old feed water heater is installed The main body barrel is left at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body barrel is joined to the newly manufactured water chamber at the installation location, thereby providing a new water heater. An assembly method for a water heater to be assembled ,
When the portion of the main body to be welded to the water chamber is manufactured from alloy steel, a carbon steel build-up weld is formed in advance on the portion of the main body to be welded to the water chamber, and the carbon steel Welding the body trunk and the water chamber together by welding the build-up welded portion to the water chamber,
A method for assembling a feed water heater , comprising: arranging a cylindrical member made of stainless steel inside a carbon steel portion, and sealing the carbon steel portion from an inner space of the main body barrel .

Supplied to the steam generator to heat the condensed water obtained steam steam turbine is discharged by cooling, the feed water heater with a body trunk and the water chamber, decomposing already old feed water heater is installed The main body barrel is left at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body barrel is joined to the newly manufactured water chamber at the installation location, thereby providing a new water heater. An assembly method for a water heater to be assembled ,
When the portion to be welded to the water chamber of the main body is manufactured from alloy steel, a carbon steel short drum is pre-welded to the portion to be welded to the water chamber of the main body,
By welding the carbon steel short drum to the water chamber, the main body drum and the water chamber are integrally welded,
A method for assembling a feed water heater, comprising forming a build-up weld made of stainless steel on an inner wall surface of a carbon steel portion to cover the carbon steel portion .

Supplied to the steam generator to heat the condensed water obtained steam steam turbine is discharged by cooling, the feed water heater with a body trunk and the water chamber, decomposing already old feed water heater is installed The main body barrel is left at the installation location, and a newly manufactured water chamber is carried into the installation location, and then the main body barrel is joined to the newly manufactured water chamber at the installation location, thereby providing a new water heater. An assembly method for a water heater to be assembled ,
When the portion to be welded to the water chamber of the main body is manufactured from alloy steel, a carbon steel short drum is pre-welded to the portion to be welded to the water chamber of the main body,
By welding the carbon steel short drum to the water chamber, the main body drum and the water chamber are integrally welded,
A method for assembling a feed water heater , comprising: arranging a cylindrical member made of stainless steel inside a carbon steel portion, and sealing the carbon steel portion from an inner space of the main body barrel .

The equipment charged to the inside of the body cylinder, the feed water heater as claimed in any one of claims 1 to 4, characterized by providing a slide member which slides an inner wall surface above the body cylinder in advance Assembly method.

While pre-joining the leg rest member to the water chamber when manufacturing the water chamber,
Method of assembling a water heater as claimed in any one of claims 1 to 5, characterized in that joining leg to the foot contact member of the water chamber which is carried at the installation site.