PULL-OUT TYPE VERTICAL SHAFT PUMP

PROBLEM TO BE SOLVED: To provide a caned pull-out type vertical shaft pump which has a pump performance similar to or more than that of a conventional vertical shaft pump made of cast and has a reduced manufacturing cost and a reduced man-hour.SOLUTION: In the pull-out type vertical shaft pump 30, a rotary shaft 1 arranged in a vertical shaft and having an impeller 2 fixed to its extremity end can be pulled out from the upper end part of a delivery bend 9. A casing includes an impeller casing 3a for housing the impeller, a guide vane means 5 arranged adjacent to the downstream side of the impeller casing and a lifting pipe 7 arranged at the downstream side of the guide vane means. The downstream side of the impeller is provided with a boss part 3b forming a flow passage between it and the guide vane means, a plurality of first flow straightening plate 4a are arranged at a circumferential-direction interval in the impeller casing and a plurality of second flow straightening plate 4b are arranged at a circumferential-direction interval in the boss part. When the rotary shaft is pulled out, the second flow straightening plate are pulled out together with the impeller. 【課題】製缶化したプルアウト型立軸ポンプにおいて、鋳物製等の従来型立軸ポンプのポンプ性能と同程度以上のポンプ性能を有するとともに製造コストおよび製作工数を低下させる。【解決手段】プルアウト型立軸ポンプ３０では、立軸に配置され先端に羽根車２が取り付けられた回転軸１を、吐出ベンド９の上端部から引き抜き可能である。ケーシングは、羽根車を収容する羽根車ケーシング３ａと、羽根車ケーシングの下流側に隣り合って設けられた案内羽根手段５と、案内羽根手段の下流側に配置される揚水管７とを有する。羽根車の下流側に、案内羽根手段との間で流路を形成するボス部３ｂを設け、羽根車ケーシングに周方向に間隔をおいて複数の第１の整流板４ａを配置し、ボス部に周方向に間隔をおいて複数の第２の整流板４ｂを配置する。回転軸を引き抜くときは第２の整流板を羽根車とともに引き抜く。【選択図】図１