Pump device

Abstract

A pump device ( 2 ), to be mounted coaxially in a pipe ( 3 ), includes an axial or mixed flow pump with a guide tube ( 7 ) arranged around a propeller portion of the pump device ( 2 ). In a mounting position, a gap ( 11 ) is formed between an upper end ( 16 ) of the guide tube ( 7 ) at an outlet portion ( 8 ) of the pump device ( 2 ) and the column pipe ( 3 ). The guide tube ( 7 ) has an elastic portion ( 12 ) connected to an outlet end of the guide tube ( 7 ). The elastic portion ( 12 ) is bendable in a radial direction towards the column pipe ( 3 ) in order to at least partially, in particular completely, close the gap ( 11 ) during operation of the pump device ( 2 ). Further, a pump system ( 1 ) includes the pump device ( 2 ).

1 . A pump device to be mounted coaxially in a pipe, the pump device comprising an axial or mixed flow pump comprising:
 a pump device propeller portion; and   a guide tube arranged around the pump device propeller portion of the pump device, wherein the guide tube has an elastic portion at it's a guide tube outlet end which elastic portion is bendable in a radial outward direction.   
     
     
         2 . A pump device according to  claim 1 , wherein the elastic portion is bendable by hydraulic pressure of fluid being pumped to an outlet portion. 
     
     
         3 . A pump device according to  claim 1 , wherein the elastic portion is bendable against an inner wall of the surrounding pipe when the pump device is running 
     
     
         4 . A pump device according to  claim 1 , wherein the elastic portion is expandable. 
     
     
         5 . A pump device according to  claim 1 , wherein the elastic portion is formed by an elastic ring mounted at the guide tube outlet end of a guide tube. 
     
     
         6 . A pump device according to  claim 1 , wherein the elastic portion is bendable at a hydraulic pressure of at least 0.2 bar. 
     
     
         7 . A pump device according to  claim 1 , wherein the pump device has such an outer diameter that the pump device fits in a pipe having a diameter between 300 mm to 2500 mm. 
     
     
         8 . A pump device according to  claim 1 , wherein the elastic portion has a height such that when the pump device is running the elastic portion is able to contact an inner wall of the pipe. 
     
     
         9 . A pump device according to  claim 1 , wherein the elastic portion is made of nitrile butadiene rubber or ethylene propylene diene monomer rubber or natural rubber. 
     
     
         10 . A pump device according to  claim 1 , wherein the elastic portion has a Shore A hardness in the range of 40 to 90. 
     
     
         11 . A pump device according to  claim 1 , wherein the elastic portion has a first axial end adjacent to the guide tube and an opposite second end, wherein a thickness of the elastic portion, at the second end, is lower than a thickness at the first end. 
     
     
         12 . A pump device according to  claim 1 , wherein the elastic portion is connected to the guide tube by gluing or by a mechanical connection, comprised by screws or bolts. 
     
     
         13 . A pump device according to  claim 1 , wherein the elastic portion has two parts, in particular two halves. 
     
     
         14 . A pump system comprising:
 a pump device;   a surrounding pipe, the pump device being mounted coaxially in the pip, the pump device comprising:   a pump device propeller portion; and   a guide tube arranged around the propeller portion of the pump device, wherein the guide tube has an elastic portion at a guide tube outlet end, which elastic portion is bendable in a radial outward direction.   
     
     
         15 . A pump system according to  claim 14 , wherein the elastic portion bends upon being subjected to hydraulic pressure of fluid being pumped to the outlet portion. 
     
     
         16 . A pump system according to  claim 14 , wherein:
 the surrounding pipe has an inner wall; and   the elastic portion bends against the inner wall of the surrounding pipe when the pump device is running   
     
     
         17 . A pump system according to  claim 14 , wherein the elastic portion comprises an elastic ring mounted at the guide tube outlet end of a guide tube. 
     
     
         18 . A pump system according to  claim 14 , wherein the elastic portion bends upon being subjected to a hydraulic pressure of at least 0.2 bar. 
     
     
         19 . A pump system according to  claim 14 , wherein:
 the surrounding pipe has a pipe diameter between 300 mm to 2500 mm;   the pump device has an outer diameter that fits in the surrounding pipe; and   the elastic portion has a height such that when the pump device is running the elastic portion contacts an inner wall of the pipe.   
     
     
         20 . A pump system according to  claim 14 , wherein:
 the elastic portion is made of a rubber selected from one or more of nitrile butadiene rubber, ethylene propylene diene monomer rubber and natural rubber; and   the elastic portion has a Shore A hardness in the range of 40 to 90.