JP3878689B2

JP3878689B2 - Multistage pump casing and manufacturing method thereof

Info

Publication number: JP3878689B2
Application number: JP14798796A
Authority: JP
Inventors: 正信奥田; 直毅下山; 友山丹治; 誠二湯原
Original assignee: Sanso Electric Co Ltd
Current assignee: Sanso Electric Co Ltd
Priority date: 1996-05-17
Filing date: 1996-05-17
Publication date: 2007-02-07
Anticipated expiration: 2016-05-17
Also published as: JPH09303295A

Description

【０００１】
【発明の属する技術分野】
本発明は、高圧多段ポンプのケーシングを構成するプレス成形により製造の鋼板製中間ケーシングに関する。
【０００２】
【従来の技術】
従来、鋼板をプレス成形して製作したポンプの中間ケーシングは、円筒状側面部の一側に有する底部側端部に形成されたインロー凸部の外径面及び端面と、開口部に形成されたインロー凹部の内径面及び端面の４箇所を機械加工することにより、径と高さの寸法精度を維持したものが知られていた。又、この従来のものを改良した特公平７−１８４３７或いは特公平７−５１９６０が提案されている。
【０００３】
これらは精度を必要とする部分の機械加工を無くし、それによって発生する加工ミスや寸法誤差を無くし、Ｏリングを使用可能とした中間ケーシングを提供するものである。これらはいずれも次段の中間ケーシングに嵌合して多段ケーシングとするために、円筒容器状ケーシングの円筒状側面部の開口部側端部を次段の円筒容器状ケーシングの底部壁面に当接するものである。ところで、最近はビルの給水押し上げ用或いはユニット冷却用などのポンプとして従来よりもさらに高圧のポンプが求められ、従って、一層高い水密性、例えば２０ｋｇ／ｃｍ² の水密性、が要求されている。そこで、中間ケーシングをポンプの軸方向にボルト締めすることにより水密に多段に嵌合した多段ポンプケーシングが使用される。ところで、上記の従来のものや提案のものは、図６の（ａ）または（ｂ）に示すように、ボルト締めする隣接段の中間ケーシングとの開口部側端部のボルトによる矢印３０向きの力の働く当接部分は鋼板の板厚に近い長さのフランジ３１の長さで隣接段の立上がり壁３２と当接するか、或いは（ｂ）に示すように鋼板の板厚である端面３３で隣接段の立上がり壁３４と当接するため、当接面積が小さく、ボルト締めのみではより高圧のポンプ内圧に耐えることができず、より高圧のポンプの中間ケーシングの構造としては従来のこのような中間ケーシングは必ずしも満足なものでなかった。そこで、より高圧にたえるケーシング構造が要求されていた。
【０００４】
【発明が解決しようとする課題】
本発明は、従来技術の上記の問題点を解消して上記の要求に応えうる構造の中間ケーシングを提供すること、即ち、ポンプ軸方向にボルト締めして多段ポンプケーシングとする場合に、ビルの給水用等としてより高圧のポンプに要求される高い水密性が確保できる構造の中間ケーシング及びその製造方法を提供することである。
【０００５】
【課題を解決するための手段】
上記の課題を解決するための本発明の手段は、請求項１の発明では、羽根車とガイドベーンを個別に内装するプレス成形鋼板製の複数の中間ケーシング１をボルト締めにより水密に嵌合して多段に重ねた多段ポンプケーシングにおいて、各中間ケーシング１は円筒状周面部２の一側に折曲する折曲部４を経て底部３を回転軸５に直角方向に有する円筒容器状に形成し、上記底部３はその内壁が戻し通路１９のガイドベーン１８に対偶するガイド壁を形成し、円筒状周面部２の端部６は内面側へ凹入する凹部７と凹部７から立上がる立上がり壁９を経て外面側へ突出する凸部８を形成して端面１０に終わり、端面１０は隣接する次段の中間ケーシング１の円筒状周面部２の折曲部４よりの上面に平行なインロー仕上面１１で載置され、底部３の端部１２は羽根車１３の流入口１４で曲折して羽根車１３の流入口フランジに当接し、上記立上がり壁９の壁内面１５は隣接する次段の中間ケーシング１の底部３の折曲部４よりの底部外面１６と平行な面当たりで当接し、凸部８の内径面は隣接段の中間ケーシング１の折曲部４外面との間にＯリング１７を嵌挿していることを特徴とする多段ポンプケーシングを構成する鋼板製中間ケーシングである。
【０００６】
請求項２の発明では、羽根車とガイドベーンを個別に内装するプレス成形鋼板製の複数の中間ケーシング１をボルト締めにより水密に嵌合して多段に重ねた多段ポンプケーシングにおいて、各中間ケーシング１は円筒状周面部２から回転軸５に直角方向に折曲する第１肩部２１を経て次段の中間ケーシング１の立上がり壁９と面当りして当接する縦壁２０を形成した後円筒状周面部２に平行に折曲して更に第２肩部２２を設けて再度回転軸５に直角方向に折曲して底部３を形成し、上記底部３はその外壁が前段の中間ケーシング１内の戻し通路１９のガイドベーン１８に対偶するガイド壁を形成し、円筒状周面部２の端部６は内面側へ凹入する凹部７と凹部７から立上がる立上がり壁９を経て外面側へ突出する凸部８を形成して端面１０に終わり、端面１０は隣接する次段の中間ケーシング１の円筒状周面部２の折曲部４の第１肩部２１よりの上面に平行なインロー仕上げ面１１で載置され、底部３の端部１２は羽根車１３の流入口１４で折曲して羽根車１３の流入口フランジに当接し、上記立上がり壁９の壁内面１５は隣接する次段の中間ケーシング１の第１肩部２１よりの縦壁２０と平行な面当りで当接し、凸部８の内径面は隣接段の中間ケーシング１の第１肩部２１外面との間にＯリング１７を嵌挿していることを特徴とする多段ポンプケーシングを構成する鋼板製中間ケーシングである。
【０００７】
請求項３の発明では、請求項１又は請求項２記載の鋼板製中間ケーシングのプレス成形による製造方法において、カムフォームにより円筒状周面部２から円筒状周面部内面側へ凹入した後凹部７を形成して該凹部７から円筒状周面部外面側へ拡径して立ち上がる立上がり壁９を形成した後、該立上がり壁９の端を円筒状周面部方向にフランジアップしてフランジを立て、続いて該フランジを円筒状内面側へリストライクして曲折して凸部８を形成することを特徴とする円筒状周面部２の端部６の成形方法である。
【０００８】
本発明の上記手段の作用を説明すると、請求項１の発明では、端部６において立上がり壁９の壁内面１５が隣接する次段の中間ケーシング１の底部３の折曲部４よりの底部外面１６と平行な面当たりで当接し、請求項２の発明では、端部６において立上がり壁９の壁内面１５が隣接する次段の中間ケーシング１の底部３の折曲部４の縦壁２０と面当たりして当接しているので、当接面積が大きいので水密性が高く強力なボルト締めにも十分に耐えることができる。従って、本発明の中間ケーシングを使用することにより高圧のポンプを得ることができる。請求項３の発明では、端部６の形状をカムフォームにより成形するので、金型精度に従って、立上がり壁９の面精度の優れたものが得られ、面当たりによる水密性が向上する。
【０００９】
【発明の実施の形態】
本発明の実施の形態を図面を参照して説明する。図１は請求項１の実施の形態を示し、図２は図１の円内を拡大して示す図である。図１は高圧多段ポンプの羽根車１３及びガイドベーン１８を内装したボルト２３によりボルト締めされた多段の中間ケーシング１の部分を主とする側面図で、上半分を断面図で示す。図において、中間ケーシング１は円筒状周面部２と折曲部４を形成して円筒軸５に略直角な方向に曲折した底部３を有する円筒容器状に形成されている。円筒状周面部２の端部６は内面側の回転軸５の方へ凹入して凹部７を形成し、さらに凹部７から円筒状周面部２方向に立上がり、立上がり壁９を形成し、立上がり壁９を経て円筒状周面部２の外面側へ突出する凸部８を形成して再び円筒状周面部２方向に曲折して端面１０に終わっている。端面１０は隣接する前段の中間ケーシング１の折曲部４よりの円筒状周面部２の上面に平行なインロー仕上面１１で載置されている。底部３はその内壁が戻し通路１９のガイドベーン１８に対偶するガイド壁を形成している。底部３の端部１２は羽根車１３の流入口１４に向いて曲折して羽根車１３のフランジの一端に当接している。底部３の内側（図で右側）には前段から送られた揚液を加圧する羽根車１３と羽根車１３から吐出した揚液を次段の高圧側（図で左側）の羽根車１３に送る戻し通路を形成するガイドベーン１８がある。そして底部３の内壁は戻し通路１９を形成する壁面を構成してガイドベーン１８と対偶している。羽根車１３は回転軸５に固着されて回転される。
【００１０】
上記構造において各中間ケーシング１は、図２に示すように、その円筒状周面部２の端部６の立上がり壁９を前段の中間ケーシング１の折曲部４直下の底部外面１６に面当りで幅の広い面で当接して両者間の水密性を保ち、さらに、凸部８の内径面には前段の中間ケーシング１の折曲部４外面との間にＯリング１７が嵌挿されて両中間ケーシングの水密性を保っている。また、円筒状周面部２の端部６の端面１０は上記のとおり前段の中間ケーシング１の円筒状周面部２の上面に載置されている。かつ、端面１０は載置される円筒状周面部２の上面に平行な面に仕上げられてインロー仕上面１１となってさらに水密性を保っている。
【００１１】
図３は請求項２の実施の形態を示し、図４は図３の円内を拡大して示す図である。これらの図において、図１及び図２に記載した符号と同一の符号は同一の構成部或いは同類の構成部を示す。図３は高圧多段ポンプの羽根車１３及びガイドベーン１８を内装したボルト２３によりボルト締めされた多段の中間ケーシング１の部分を主とする側面図で、上半分を断面図で示す。中間ケーシング１は円筒状周面部２が折曲部４で回転軸５に直角方向に折曲して第１肩部２１を形成している。次いで縦壁２０を形成している。縦壁２０は次段の中間ケーシング１の立上がり壁９と面当りして当接する。さらに、円筒状周面部２に平行に曲折して第２肩部２２を形成した後、再び回転軸５に直角方向に折曲して底部３を有する円筒容器状に形成されている。円筒状周面部２の端部６は内面側の回転軸５の方へ凹入して凹部７を形成し、さらに凹部７から円筒状周面部２方向に立上がり、立上がり壁９を形成し、立上がり壁９を経て円筒状周面部２の外面側へ突出する凸部８を形成して再び円筒状周面部２方向に曲折して端面１０に終わっている。端面１０は隣接する次段の中間ケーシング１の折曲部４よりの円筒状周面部２の上面に平行なインロー仕上面１１で載置されている。底部３はその外壁が前段の戻し通路１９のガイドベーン１８に対偶するガイド壁を形成している。底部３の端部１２は羽根車１３の流入口１４に向いて曲折して羽根車１３のフランジの一端に当接している。底部３の内側（図で左側）には前段の戻し通路１９から流入した揚液を加圧する羽根車１３と羽根車１３から吐出した揚液を次段の高圧側（図で左側）の羽根車１３に送る戻し通路１９を形成するガイドベーン１８がある。そして次段の底部３の外壁は本段の戻し通路１９を形成する壁面を構成して本段のガイドベーン１８と対偶している。そして羽根車１３は回転軸５に固着されて回転される。
【００１２】
以上の構成から理解されるように請求項２の発明の実施の形態では、中間ケーシング１の円筒状周面部２の端部６は請求項１の発明の実施の形態における円筒状周面部２の端部６と図面上で逆向きに配置されている。即ちガイドベーン１８と対偶してして戻し通路１９を形成する壁は次段の底部３の外壁である。また、、請求項２の発明の実施の形態では、折曲部４で回転軸５に直角方向に折曲して第１肩部２１を形成し、次いで縦壁２０を形成した後、円筒状周面部２に平行に曲折して第２肩部２２を形成した後、再び回転軸５に直角方向に折曲して底部３となっている。従って、１個の羽根車１３と１個の戻し通路１９を有する単位ポンプ室は、羽根車１３の径の大きなハイタイプとすることができる。
【００１３】
上記構造において各中間ケーシング１は、図４に示すように、その円筒状周面部２の端部６の立上がり壁９を後段の中間ケーシング１の折曲部４の第１肩部２１直下の縦壁２０に面当たりで幅の広い面で当接して両者間の水密性を保ち、さらに、凸部８の内径面には後段の中間ケーシング１の折曲部４外面との間にＯリング１７が嵌挿されて両中間ケーシングの水密性を保っている。また、円筒状周面部２の端部６の端面１０は上記のとおり次段の中間ケーシング１の円筒状周面２の上面に載置されている。かつ、端面１０は載置される円筒状周面部２の上面に平行な面に仕上げられてインロー仕上面１１となってさらに水密性を保っている。
【００１４】
請求項３の発明の実施の形態を説明する。請求項３の発明は、請求項１或いは請求項２の発明の多段ポンプケーシングの円筒容器状の中間ケーシング１を、鋼板からプレス成形により製造する方法の発明である。図７ないし図９を参照してその製造方法を説明する。先ず、請求項１の発明の中間ケーシング１はロータイプのもので、その製造工程段階の各ワークの断面端面を示す図７の（ａ）ないし（ｋ）により説明すると、（ａ）は１枚の円形の鋼板のブランクで、このブランクをドローにより即ち絞り加工して外周部に円筒状周面部２を立設して中央部に膨出した底部３を有する（ｂ）の形状に成形し、次いでリストラいくして（ｃ）の形状に成形した後、最外周を切断除去し底部３の中央を円形に穿孔する（ｄ）のトリム及びピアス工程を行う。次いで（ｅ）ないし（ｇ）のカムフォーム（「カム型による成形」をいう。）、カムリストライク（「カム型によるリストライク」をいう。）、カムリストライク決め（「カム型によるリストライク決め」をいう。）の各工程を実施する。この工程は最も成形の困難な工程であり、このカムフォームで使用する金型を図９に示す。図９は中心線を挟んで対称的に右側は成形前のワークのセット状態を示し、左側は成形終了時の金型の位置を模式的に示す図で、同図において、Ｗはワークを示し、▲１▼、▲２▼の金型は左右に動き、▲３▼、▲４▼の金型は上下に動く。各金型のハッチで示す部材はその戻り用バネを示す。ワークＷは金型▲２▼の下端中心側のエッジ部により円筒状円周面２の端部６の凹入部７が成形される。ついで、工程（ｈ）で中央部バーリングでフランジを立て底部の端部１２が成形され、さらに端部６が先端がトリムされる。（ｉ）で端部６の先端部にフランジを立て、（ｊ）でこのフランジを上下にリストライクして内方に曲げ最終工程の（ｋ）でフランジ決めして円筒状周面部２に端部６の端面１０を成形してプレス成形を終わる。
【００１５】
請求項２の発明のハイタイプの中間ケーシングの製造工程は図８に示す。図８は図７と同様にその製造工程段階の各ワークの断面端面を示す。（ａ）は鋼板のブランクで、（ｂ）はドロー、（ｃ）はフォーム成形して第１肩部２１及び第２肩部２２を成形する。（ｄ）はリストライクして更に（ｅ）のトリムで最外周を切断除去し、この状態で一度焼なまして加工硬化したワークを軟化させ、更に上記した図９に示す金型によるカムフォーム工程と同様のカムフォーム工程（ｆ）で円筒状周面部２の端部６の凹入部７を成形する。次いで、（ｇ）のカムリストライク、（ｈ）のカムリストライク決めの後、（ｉ）で底部３の端部１２をワークＷの中心をピアスして成形し、ワークＷの周縁をトリムして端部６の先端の端面１０を設ける。（ｊ）でワークＷの中央の孔の周囲をバーリングして端部１２を内方に向け、端部６の先端を内方に折曲してフランジを立て、（ｋ）で立てたフランジをリストライクしてさらに内方に折曲して端部６の凸部８を成形し、（ｌ）でフランジ決めして全工程を終了する。上記の工程において、図９の金型のカムフォームにより円筒状周面部２の端部６の立上がり壁９が形成される。
さらに、本発明では円筒状周面部２の端部６の強度を確保し、かつ端部６がより強力な水密性を保持するためには、図５に示すように、端部６の凹部７及び凸部８或いは隣接段の折曲部４或いは第１肩部２１のそれぞれの絞り形状の曲率半径Ｒの２４、２５、２６の大きさをを鋼板の板厚以下とすることが望まれる。また、端面２９のハッチ部分にはインロー切削加工ににより同心度の精度を確保することが望まれ、さらに、多段ケーシングへの組立て時の中間ケーシングの回転軸５方向のスラスト方向の位置決めとボルトしめつけによる圧縮応力による変形に耐えかつ面当たりの寸法精度を確保するため立上がり壁９と折曲部４の底部１６或いは第１肩部２１の縦壁２０のハッチ部分には面切削加工壁面２７及び面切削加工壁面２８を設けることが望まれる。Ｏリング１７は内圧用として端部６の凸部８の内面の半径Ｒ２５内に挿嵌されており、その状態のＯリング１７に隣接段の中間ケーシング１のＲ形状の折曲部４或いは第１肩部２１を組み合わせても、Ｏリング１７を疵つけることなく組付けができる。
【００１６】
【発明の効果】
以上説明したように、本発明の中間ケーシングは隣接段との当接部が面当たりでかつボルト締めの圧縮方向に幅広い当接面積を確保しているので、シーリング性がより高く、かつ通常のＯリングを使用することができかつＯリングの挿嵌部分の形状がＯリングを疵つけることのない形状に形成されている。さらに中間ケーシングの製作において、円筒状周面部の端部の成形をカムフォームにより行うので金型精度により高い寸法精度で成形することができる。
【図面の簡単な説明】
【図１】本発明の高圧多段ポンプのポンプ部分を主とするボルト締めされた多段の中間ケーシングの上半分を断面図で示す側面図である。
【図２】図１の部分拡大図である。
【図３】本発明の他の実施形態の高圧多段ポンプのポンプ部分を主とするボルト締めされた多段の中間ケーシングの上半分を断面図で示す側面図である。
【図４】図３の部分拡大図である。
【図５】本発明における中間ケーシングの隣接段との当接部分の拡大説明図である。
【図６】従来の中間ケーシングの隣接段との当接部分の拡大説明図である。
【図７】本発明の中間ケーシングの成形工程を説明する図である。
【図８】本発明の他の実施形態の中間ケーシングの成形工程を説明する図である。
【図９】本発明の中間ケーシングの成形する金型構造を模式的に示すずである。
【符号の簡単な説明】
１中間ケーシング
２円筒状周面部
３底部
４折曲部
５回転軸
６端部
７凹部
８凸部
９立上がり壁
１０端面
１１インロー仕上面
１２端部
１３羽根車
１４流入口
１５壁内面
１６底部外面
１７Ｏリング
１８ガイドベーン
１９戻し通路
２０縦壁
２１第１肩部
２２第２肩部
２３ボルト
２４凹部７の曲率半径Ｒ
２５凸部８の曲率半径Ｒ
２６折曲部４又は第１肩部２１の曲率半径Ｒ
２７面切削加工壁面
２８面切削加工壁面
２９端面
３０ボルト締めの力の作用方向を示す矢印
３１フランジ
３２立上がり壁
３３端面
３４立上がり壁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an intermediate casing made of steel plate manufactured by press forming that constitutes a casing of a high-pressure multistage pump.
[0002]
[Prior art]
Conventionally, an intermediate casing of a pump manufactured by press-molding a steel plate was formed on the outer diameter surface and end surface of an inlay convex portion formed on the bottom side end portion on one side of the cylindrical side surface portion, and on the opening portion. It has been known to maintain the dimensional accuracy of the diameter and the height by machining the inner surface and the end surface of the inlay recess. Further, Japanese Patent Publication No. 7-18437 or Japanese Patent Publication No. 7-51960 has been proposed, which is an improvement of this conventional one.
[0003]
These provide an intermediate casing that eliminates machining of parts that require accuracy, eliminates machining errors and dimensional errors, and makes it possible to use an O-ring. In order for these to fit into the intermediate casing of the next stage to make a multistage casing, the opening side end of the cylindrical side surface portion of the cylindrical container casing contacts the bottom wall surface of the next cylindrical container casing. Is. By the way, recently, a pump having a higher pressure than the conventional pump is required as a pump for pushing up the water supply of a building or cooling a unit. Therefore, a higher water tightness, for example, a water tightness of 20 kg / cm ² is required. Therefore, a multistage pump casing is used in which the intermediate casing is bolted in the axial direction of the pump to fit in multiple stages in a watertight manner. By the way, as shown in FIG. 6 (a) or (b), the above-mentioned conventional and proposed ones are oriented in the direction of arrow 30 by the bolts at the end portions on the opening side with the intermediate casing of the adjacent stage to be bolted. The abutting portion where the force acts is in contact with the rising wall 32 of the adjacent step by the length of the flange 31 having a length close to the plate thickness of the steel plate, or at the end face 33 which is the plate thickness of the steel plate as shown in FIG. Since it abuts against the rising wall 34 of the adjacent stage, the abutment area is small, and it is difficult to withstand a higher pressure in the pump by bolting alone. The casing was not always satisfactory. Therefore, a casing structure that can withstand higher pressure has been required.
[0004]
[Problems to be solved by the invention]
The present invention provides an intermediate casing having a structure that can solve the above-mentioned problems of the prior art and meet the above-mentioned requirements, that is, when a multi-stage pump casing is bolted in the pump axial direction to form a multistage pump casing. An object of the present invention is to provide an intermediate casing having a structure capable of ensuring the high water tightness required for a higher pressure pump for water supply and the like, and a method for manufacturing the intermediate casing.
[0005]
[Means for Solving the Problems]
The means of the present invention for solving the above-described problems is that, in the invention of claim 1, a plurality of intermediate casings 1 made of press-formed steel plates, each having an impeller and a guide vane, are fitted in a watertight manner by bolting. In each of the multistage pump casings stacked in multiple stages, each intermediate casing 1 is formed in a cylindrical container shape having a bottom portion 3 in a direction perpendicular to the rotation shaft 5 via a bent portion 4 that is bent to one side of the cylindrical peripheral surface portion 2. The bottom 3 forms a guide wall whose inner wall faces the guide vane 18 of the return passage 19, and the end 6 of the cylindrical peripheral surface 2 is recessed into the inner surface and a rising wall rising from the recess 7. 9 is formed in a protruding portion 8 projecting to the outer surface side and ends at the end surface 10, and the end surface 10 is inlay finish parallel to the upper surface from the bent portion 4 of the cylindrical peripheral surface portion 2 of the adjacent intermediate casing 1 of the next stage. Placed on the surface 11 of the bottom 3 The portion 12 is bent at the inlet 14 of the impeller 13 and abuts against the inlet flange of the impeller 13, and the wall inner surface 15 of the rising wall 9 is the bent portion 4 of the bottom 3 of the adjacent intermediate casing 1 of the next stage. Further, the O-ring 17 is fitted between the inner surface of the convex portion 8 and the outer surface of the bent portion 4 of the adjacent intermediate casing 1. It is the intermediate casing made from steel plate which comprises a multistage pump casing.
[0006]
According to the second aspect of the present invention, in the multistage pump casing in which a plurality of intermediate casings 1 made of press-formed steel plates , in which the impeller and the guide vane are individually installed, are watertightly fitted by bolting and stacked in multiple stages, each intermediate casing 1 Is formed in a cylindrical shape after forming a vertical wall 20 that comes into contact with and comes into contact with the rising wall 9 of the intermediate casing 1 of the next stage through a first shoulder portion 21 bent in a direction perpendicular to the rotating shaft 5 from the cylindrical peripheral surface portion 2. Bent in parallel with the peripheral surface 2 and further provided with a second shoulder 22 and again bent in the direction perpendicular to the rotary shaft 5 to form the bottom 3, the bottom 3 has an outer wall in the intermediate casing 1 in the preceding stage. A guide wall that opposes the guide vane 18 of the return passage 19 is formed, and the end portion 6 of the cylindrical peripheral surface portion 2 protrudes to the outer surface side through a recessed portion 7 recessed into the inner surface side and a rising wall 9 rising from the recessed portion 7. Forming a convex portion 8 that ends on the end face 10 The end face 10 is placed on an inlay finish surface 11 parallel to the upper surface from the first shoulder portion 21 of the bent portion 4 of the cylindrical peripheral surface portion 2 of the adjacent intermediate casing 1 of the next stage, and the end portion of the bottom portion 3. 12 is bent at the inlet 14 of the impeller 13 and abuts against the inlet flange of the impeller 13, and the wall inner surface 15 of the rising wall 9 is from the first shoulder 21 of the adjacent intermediate casing 1 at the next stage. The multi-stage is characterized in that the O-ring 17 is fitted between the inner surface of the projecting portion 8 and the outer surface of the first shoulder portion 21 of the adjacent intermediate casing 1. It is the steel plate intermediate casing which comprises a pump casing.
[0007]
In the invention of claim 3, in the manufacturing method by press forming of the steel sheet intermediate casing according to claim 1 or claim 2, the rear recess 7 is recessed from the cylindrical peripheral surface portion 2 to the inner surface side of the cylindrical peripheral surface portion by cam foam. And forming a rising wall 9 that rises from the concave portion 7 toward the outer surface side of the cylindrical peripheral surface portion, and then raises the end of the rising wall 9 in the direction of the cylindrical peripheral surface portion to raise a flange. Then, the flange 6 is wrist-like to the cylindrical inner surface side and bent to form the convex portion 8, thereby forming the end portion 6 of the cylindrical peripheral surface portion 2.
[0008]
The operation of the above-mentioned means of the present invention will be explained. In the invention of claim 1, the bottom outer surface from the bent portion 4 of the bottom portion 3 of the intermediate casing 1 of the next stage in which the wall inner surface 15 of the rising wall 9 is adjacent at the end portion 6. In the invention according to claim 2, the wall 6 of the rising wall 9 is adjacent to the vertical wall 20 of the bent portion 4 of the bottom portion 3 of the intermediate casing 1 of the next stage. Since it is in contact with the surface and has a large contact area, it is highly watertight and can sufficiently withstand strong bolting. Therefore, a high-pressure pump can be obtained by using the intermediate casing of the present invention. In the invention of claim 3, since the shape of the end portion 6 is formed by the cam foam, an excellent surface accuracy of the rising wall 9 is obtained according to the mold accuracy, and the water tightness due to the contact with the surface is improved.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of claim 1 and FIG. 2 is an enlarged view of the inside of the circle of FIG. FIG. 1 is a side view mainly showing a portion of a multistage intermediate casing 1 bolted by a bolt 23 having an impeller 13 and a guide vane 18 of a high-pressure multistage pump, and an upper half thereof is shown in a sectional view. In the drawing, the intermediate casing 1 is formed in a cylindrical container shape having a cylindrical peripheral surface portion 2 and a bent portion 4 and having a bottom portion 3 bent in a direction substantially perpendicular to the cylindrical shaft 5. The end 6 of the cylindrical peripheral surface portion 2 is recessed toward the rotary shaft 5 on the inner surface side to form a concave portion 7, and further rises from the concave portion 7 in the direction of the cylindrical peripheral surface portion 2 to form a rising wall 9. A convex portion 8 that protrudes to the outer surface side of the cylindrical peripheral surface portion 2 through the wall 9 is formed, and is bent again in the direction of the cylindrical peripheral surface portion 2 to end at the end surface 10. The end surface 10 is placed on an inlay finish surface 11 parallel to the upper surface of the cylindrical peripheral surface portion 2 from the bent portion 4 of the adjacent intermediate casing 1 in the preceding stage. The bottom 3 forms a guide wall whose inner wall faces the guide vane 18 of the return passage 19. The end 12 of the bottom 3 bends toward the inlet 14 of the impeller 13 and abuts one end of the flange of the impeller 13. Inside the bottom 3 (right side in the figure), the impeller 13 that pressurizes the pumped liquid sent from the previous stage and the pumped liquid discharged from the impeller 13 is sent to the impeller 13 on the high pressure side (left side in the figure) of the next stage. There is a guide vane 18 that forms a return passage. The inner wall of the bottom 3 constitutes a wall surface forming a return passage 19 and is opposed to the guide vane 18. The impeller 13 is fixed to the rotating shaft 5 and rotated.
[0010]
As shown in FIG. 2, each intermediate casing 1 in the above structure has a rising wall 9 at the end 6 of the cylindrical peripheral surface portion 2 in contact with the bottom outer surface 16 immediately below the bent portion 4 of the preceding intermediate casing 1. A wide surface is contacted to maintain water tightness between the two, and an O-ring 17 is fitted between the inner surface of the convex portion 8 and the outer surface of the bent portion 4 of the intermediate casing 1 in the previous stage. The watertightness of the intermediate casing is maintained. Further, the end surface 10 of the end portion 6 of the cylindrical peripheral surface portion 2 is placed on the upper surface of the cylindrical peripheral surface portion 2 of the preceding intermediate casing 1 as described above. And, the end face 10 is kept more water tightness becomes spigot finish surface 11 is finished to a plane parallel to the upper surface of a circular cylindrical peripheral surface 2 placed.
[0011]
FIG. 3 shows an embodiment of claim 2 and FIG. 4 is an enlarged view of the inside of the circle of FIG. In these drawings, the same reference numerals as those shown in FIGS. 1 and 2 indicate the same or similar components. FIG. 3 is a side view mainly showing a part of the multistage intermediate casing 1 bolted by a bolt 23 in which an impeller 13 and a guide vane 18 of a high-pressure multistage pump are housed, and an upper half is shown in a sectional view. In the intermediate casing 1, a cylindrical peripheral surface portion 2 is bent at a bending portion 4 in a direction perpendicular to the rotation shaft 5 to form a first shoulder portion 21. Next, the vertical wall 20 is formed. The vertical wall 20 abuts against and comes into contact with the rising wall 9 of the next intermediate casing 1. Further, the second shoulder portion 22 is formed by bending in parallel to the cylindrical peripheral surface portion 2, and then bent again in the direction perpendicular to the rotation shaft 5 to form a cylindrical container having the bottom portion 3. The end 6 of the cylindrical peripheral surface portion 2 is recessed toward the rotary shaft 5 on the inner surface side to form a concave portion 7, and further rises from the concave portion 7 in the direction of the cylindrical peripheral surface portion 2 to form a rising wall 9. A convex portion 8 that protrudes to the outer surface side of the cylindrical peripheral surface portion 2 through the wall 9 is formed, and is bent again in the direction of the cylindrical peripheral surface portion 2 to end at the end surface 10. The end surface 10 is mounted on an inlay finish surface 11 parallel to the upper surface of the cylindrical peripheral surface portion 2 from the bent portion 4 of the adjacent intermediate casing 1 at the next stage. The bottom 3 forms a guide wall whose outer wall faces the guide vane 18 of the return passage 19 in the preceding stage. The end 12 of the bottom 3 bends toward the inlet 14 of the impeller 13 and abuts one end of the flange of the impeller 13. On the inner side (left side in the figure) of the bottom portion 3, the impeller 13 that pressurizes the pumped liquid flowing in from the previous return passage 19 and the pumped liquid discharged from the impeller 13 on the high pressure side (left side in the figure) of the next stage There is a guide vane 18 that forms a return passage 19 to 13. The outer wall of the bottom 3 of the next stage constitutes a wall surface that forms the return passage 19 of the main stage and is opposed to the guide vane 18 of the main stage. The impeller 13 is fixed to the rotating shaft 5 and rotated.
[0012]
As understood from the above configuration, in the embodiment of the invention of claim 2, the end portion 6 of the cylindrical peripheral surface portion 2 of the intermediate casing 1 is the same as that of the cylindrical peripheral surface portion 2 in the embodiment of the invention of claim 1. It arrange | positions in the direction opposite to the edge part 6 and drawing. That is, the wall that forms the return passage 19 in opposition to the guide vane 18 is the outer wall of the bottom 3 of the next stage. Further, in the embodiment of the invention of claim 2, the first shoulder portion 21 is formed by bending the bending portion 4 in the direction perpendicular to the rotation shaft 5, and then the vertical wall 20 is formed. After the second shoulder portion 22 is formed by being bent in parallel with the peripheral surface portion 2, the second shoulder portion 22 is again bent in the direction perpendicular to the rotation shaft 5 to form the bottom portion 3. Therefore, the unit pump chamber having one impeller 13 and one return passage 19 can be a high type with a large diameter of the impeller 13.
[0013]
As shown in FIG. 4, each intermediate casing 1 in the above structure has a vertical wall immediately below the first shoulder 21 of the bent portion 4 of the intermediate casing 1 on the rising wall 9 at the end 6 of the cylindrical peripheral surface portion 2. The wall 20 is in contact with the surface with a wide surface to maintain water tightness between the two, and the O-ring 17 is provided between the inner diameter surface of the convex portion 8 and the outer surface of the bent portion 4 of the intermediate casing 1 at the rear stage. Is inserted to maintain the water tightness of both intermediate casings. Further, the end surface 10 of the end portion 6 of the cylindrical peripheral surface portion 2 is placed on the upper surface of the cylindrical peripheral surface 2 of the next-stage intermediate casing 1 as described above. And, the end face 10 is kept more water tightness becomes spigot finish surface 11 is finished to a plane parallel to the upper surface of a circular cylindrical peripheral surface 2 placed.
[0014]
An embodiment of the invention of claim 3 will be described. Invention of Claim 3 is invention of the method of manufacturing the cylindrical casing-shaped intermediate casing 1 of the multistage pump casing of Claim 1 or Claim 2 from a steel plate by press molding. The manufacturing method will be described with reference to FIGS. First, the intermediate casing 1 of the invention of claim 1 is of a low type, and will be described with reference to FIGS. 7 (a) to 7 (k) showing the cross-sectional end faces of each workpiece in the manufacturing process stage. A blank of a steel plate, and this blank is drawn by drawing, that is, formed into a shape of (b) having a bottom 3 that swells in the center by standing a cylindrical peripheral surface 2 on the outer periphery, Next, after restructuring and forming into the shape of (c), the trimming and piercing process of (d) is performed in which the outermost periphery is cut and removed and the center of the bottom portion 3 is formed in a circular shape. Next, (e) to ( g ) cam foam (referred to as “molding by cam mold”) , cam wrist like ( referred to as “restricting by cam mold” ) , cam wrist like determination (“restriction determination according to cam mold”) )) Is carried out. This step is the most difficult step to mold, and the mold used in this cam foam is shown in FIG. Figure 9 shows a set state of the pre-symmetrically right across the center line forming the work, at the left hand side of the drawing is to indicate the position of the mold at the end of the molding schematically, in figure, W is shown a workpiece , (1) and (2) molds move left and right, and (3) and (4) molds move up and down. A member indicated by a hatch of each mold indicates the return spring. In the workpiece W, the recessed portion 7 of the end portion 6 of the cylindrical circumferential surface 2 is formed by the edge portion on the lower center side of the mold (2). Next, in step (h), the end portion 12 of the bottom portion is formed by raising the flange with the central burring, and the end portion of the end portion 6 is trimmed. In (i), a flange is set up at the tip of the end portion 6, and in (j), the flange is vertically restructured and bent inward. The flange is determined in (k) of the final step, and the end is formed on the cylindrical peripheral surface portion 2. The end surface 10 of the part 6 is molded and the press molding is finished.
[0015]
The manufacturing process of the high type intermediate casing of the invention of claim 2 is shown in FIG. FIG. 8 shows the cross-sectional end face of each workpiece in the manufacturing process step as in FIG. (A) is a blank of a steel plate, (b) is a draw, and (c) is foam-formed to form the first shoulder portion 21 and the second shoulder portion 22. (D) is re-sliced, and the outermost periphery is cut and removed by the trim of (e), and the work-hardened workpiece is softened by annealing once in this state, and the cam foam process by the mold shown in FIG. The recessed part 7 of the edge part 6 of the cylindrical peripheral surface part 2 is shape | molded by the same cam foam process (f). Next, after determining the cam wrist like in (g) and the cam wrist like in (h), the end 12 of the bottom 3 is formed by piercing the center of the workpiece W in (i), and the peripheral edge of the workpiece W is trimmed to the end. An end face 10 at the tip of the portion 6 is provided. In (j), the periphery of the central hole of the workpiece W is burred, the end 12 is directed inward, the tip of the end 6 is bent inward, and the flange is raised. Re-striking and further bending inwardly to form the convex portion 8 of the end portion 6, and determining the flange in (l), the whole process is completed. In the above process, the rising wall 9 of the end 6 of the cylindrical peripheral surface portion 2 is formed by the cam form of the mold shown in FIG.
Furthermore, in the present invention, in order to ensure the strength of the end portion 6 of the cylindrical peripheral surface portion 2 and to keep the water tightness of the end portion 6 as shown in FIG. In addition, it is desirable that the diameters 24, 25, and 26 of the curvature radii R of the respective drawn shapes of the convex portion 8 or the adjacent bent portion 4 or the first shoulder portion 21 be equal to or less than the plate thickness of the steel plate. In addition, it is desirable to ensure the accuracy of concentricity by hatching in the hatched portion of the end face 29. Furthermore, the positioning of the intermediate casing in the direction of the thrust axis 5 and the bolting of the intermediate casing during assembly into the multistage casing are desired. In order to withstand deformation caused by the compressive stress caused by the above and to ensure the dimensional accuracy per surface, the hatched portion of the rising wall 9 and the bottom portion 16 of the bent portion 4 or the vertical wall 20 of the first shoulder portion 21 has a face-cutting wall surface 27 and a surface. It is desirable to provide a cutting wall surface 28. The O-ring 17 is inserted into the radius R25 of the inner surface of the convex portion 8 of the end portion 6 for internal pressure, and the R-shaped bent portion 4 or the second portion of the intermediate casing 1 adjacent to the O-ring 17 in this state. Even if one shoulder portion 21 is combined, it is possible to assemble the O-ring 17 without scuffing.
[0016]
【The invention's effect】
As described above, the intermediate casing of the present invention has a contact portion with an adjacent step per surface and a wide contact area in the compression direction of bolt tightening, so that the sealing property is higher and the normal casing An O-ring can be used, and the shape of the insertion portion of the O-ring is formed so as not to catch the O-ring. Further, in the production of the intermediate casing, the end portion of the cylindrical peripheral surface portion is formed by cam foam, so that it can be formed with higher dimensional accuracy due to the mold accuracy.
[Brief description of the drawings]
FIG. 1 is a side view showing a cross-sectional view of an upper half of a bolted multistage intermediate casing mainly including a pump portion of a high-pressure multistage pump according to the present invention.
FIG. 2 is a partially enlarged view of FIG.
FIG. 3 is a side view showing a cross-sectional view of an upper half of a bolted multi-stage intermediate casing mainly including a pump portion of a high-pressure multi-stage pump according to another embodiment of the present invention.
4 is a partially enlarged view of FIG. 3;
FIG. 5 is an enlarged explanatory view of a contact portion with an adjacent step of an intermediate casing in the present invention.
FIG. 6 is an enlarged explanatory view of a contact portion with an adjacent step of a conventional intermediate casing.
FIG. 7 is a diagram illustrating a molding process of the intermediate casing according to the present invention.
FIG. 8 is a diagram illustrating a molding process of an intermediate casing according to another embodiment of the present invention.
FIG. 9 is a schematic diagram showing a mold structure for molding the intermediate casing of the present invention.
[Brief description of symbols]
DESCRIPTION OF SYMBOLS 1 Intermediate casing 2 Cylindrical peripheral surface part 3 Bottom part 4 Bending part 5 Rotating shaft 6 End part 7 Concave part 8 Convex part 9 Rising wall 10 End surface 11 Inner finish surface 12 End part 13 Impeller 14 Inlet port 15 Wall inner surface 16 Bottom outer surface 17 O-ring 18 Guide vane 19 Return passage 20 Vertical wall 21 First shoulder 22 Second shoulder 23 Bolt 24 Radius of curvature R of recess 7
25 Curvature radius R of convex part 8
26 Curvature radius R of the bent portion 4 or the first shoulder 21
27 Face-cutting wall surface 28 Face-cutting wall surface 29 End face 30 Arrow 31 indicating the direction of action of the bolt tightening force Flange 32 Rising wall 33 End face 34 Rising wall

Claims

In a multistage pump casing in which a plurality of intermediate casings 1 made of press-formed steel sheets, each having an impeller and a guide vane, are joined in a watertight manner by bolting and stacked in multiple stages, each intermediate casing 1 has a cylindrical peripheral surface portion 2. A cylindrical container having a bottom 3 in a direction perpendicular to the rotation shaft 5 is formed through a bent portion 4 that is bent to one side, and the bottom 3 has a guide wall whose inner wall faces the guide vane 18 of the return passage 19. The end portion 6 of the cylindrical peripheral surface portion 2 is formed into a concave portion 7 recessed into the inner surface side and a convex portion 8 projecting to the outer surface side through a rising wall 9 rising from the concave portion 7, and ends at the end surface 10. 10 is placed on an inlay finish surface 11 parallel to the upper surface of the bent portion 4 of the cylindrical peripheral surface portion 2 of the adjacent intermediate casing 1 of the next stage, and the end portion 12 of the bottom portion 3 is an inlet 14 of the impeller 13. Bend at the inlet of the impeller 13 The wall inner surface 15 of the rising wall 9 is in contact with a surface parallel to the bottom outer surface 16 from the bent portion 4 of the bottom 3 of the adjacent intermediate casing 1, and the inner diameter surface of the convex portion 8. Is an intermediate casing made of steel plate constituting a multistage pump casing, wherein an O-ring 17 is inserted between the outer surface of the bent portion 4 of the intermediate casing 1 in the adjacent stage.

In a multi-stage pump casing in which a plurality of intermediate casings 1 made of press-formed steel plates, in which an impeller and guide vanes are individually installed, are watertightly fitted by bolting and stacked in multiple stages, each intermediate casing 1 is formed from a cylindrical peripheral surface portion 2. After forming a vertical wall 20 that comes into contact with and comes into contact with the rising wall 9 of the intermediate casing 1 of the next stage through a first shoulder 21 bent in a direction perpendicular to the rotating shaft 5, it is folded in parallel with the cylindrical peripheral surface portion 2. Further bent, a second shoulder 22 is provided and bent again at a right angle to the rotary shaft 5 to form a bottom 3. The bottom 3 has a guide vane for the return passage 19 in the intermediate casing 1 whose outer wall is in the preceding stage. 18 is formed as a guide wall, and the end portion 6 of the cylindrical peripheral surface portion 2 is formed with a concave portion 7 that is recessed into the inner surface side and a convex portion 8 that protrudes toward the outer surface side through a rising wall 9 rising from the concave portion 7. End face 10 and end face 10 is adjacent The intermediate casing 1 of the next stage is placed with an inlay finish surface 11 parallel to the upper surface of the bent portion 4 of the cylindrical peripheral surface portion 2 from the first shoulder portion 21, and the end portion 12 of the bottom portion 3 is connected to the impeller 13. The wall inner surface 15 of the rising wall 9 is parallel to the vertical wall 20 from the first shoulder portion 21 of the adjacent next-stage intermediate casing 1 by bending at the inlet 14 and contacting the inlet flange of the impeller 13. A steel plate constituting a multi-stage pump casing , wherein the O-ring 17 is fitted between the inner surface of the convex portion 8 and the outer surface of the first shoulder portion 21 of the adjacent intermediate casing 1. Intermediate casing made.

In the manufacturing method by press molding of the steel sheet intermediate casing according to claim 1 or 2, the concave portion 7 is formed by recessing the cylindrical peripheral surface portion 2 from the cylindrical peripheral surface portion 2 to the inner surface side of the cylindrical peripheral surface portion with a cam foam. After forming a rising wall 9 that expands from the outer peripheral surface of the cylindrical peripheral surface to rise, the end of the rising wall 9 is flanged up in the direction of the cylindrical peripheral surface, and then the flange is raised. The method for forming the end portion 6 of the cylindrical peripheral surface portion 2 is characterized in that the convex portion 8 is formed by bending like bending to the side.