Delivery Pump

Abstract

A delivery pump for conveying a liquid between a pump inlet and a pump outlet, the pump being constructed as a single-stage centrifugal pump with a radial impeller ( 2 ) having a centrifugal construction arranged rotatably in an impeller chamber ( 6 ) of a pump casing ( 1 ); the impeller being connected to a variable-speed drive motor ( 5 ) variable in speed into the five-digit range of revolutions per minute, and the impeller receiving liquid flow centrally, and being provided with radially-extending delivery ducts ( 3 ), and at outside impeller diameters of up to 55 mm developing rotational speed-dependent delivery heads of up to 300 m. For use in a process engineering system, the delivery pump is designed for nominal operation in the form of continuous centrifugal pump part-load operation with delivery rates in the range of 0 ml/min to 7000 ml/min; the nominal operation is characterized by a centrifugal pump part-load-specific rotational speed nq TL ≧0.05≦10 (l/min), and the impeller chamber ( 6 ) comprises one or more pump outlet ducts ( 13 ) located on the circumference at acute angles to or tangentially to the outside diameter of the radial impeller.

1 . A delivery pump for conveying a liquid between a pump inlet and a pump outlet, said pump being constructed as a single-stage centrifugal pump with a radial impeller having a centrifugal construction arranged rotatably in an impeller chamber of a pump casing, said impeller being connected to a variable-speed drive motor variable in speed into the five-digit range of revolutions per minute, and said impeller receiving liquid flow centrally, being provided with radially-extending delivery ducts, and at outside impeller diameters of up to 55 mm developing rotational speed-dependent delivery heads of up to 300 m; 
     wherein:
 the delivery pump is dimensioned for nominal operation in the form of continuous centrifugal pump part-load operation with delivery rates in the range of 0 ml/min to 7000 ml/min; 
 the nominal operation is characterized by a centrifugal pump part-load-specific rotational speed nq TL ≧0.05≦10 (l/min), and 
 the impeller chamber has a circumference provided with one or more pump outlet ducts arranged at an acute angle to or tangentially to the outside diameter of the radial impeller. 
 
   
   
       2 . A delivery pump as claimed in  claim 1 , wherein the nominal operation has a centrifugal pump part-load-specific rotational speed nq TL ≧0.05≦3 (l/min). 
   
   
       3 . A delivery pump as claimed in  claim 1 , wherein the delivery pump is dimensioned for a centrifugal pump part-load operating range nq TL <2.5. 
   
   
       4 . A delivery pump as claimed in  claim 1 , wherein the radial impeller has an outside diameter of at most 70 mm. 
   
   
       5 . A delivery pump as claimed in  claim 1 , wherein the pump casing with the radial impeller arranged therein has a residual volume of less than 30 milliliters. 
   
   
       6 . A delivery pump as claimed in  claim 5 , wherein the impeller chamber has an inside diameter which is at most 4% larger than the outside diameter of the impeller. 
   
   
       7 . A delivery pump as claimed in  claim 1 , wherein an increased dynamic pressure is generated at the pump outlet as the size of the impeller chamber surrounding the radial impeller is reduced. 
   
   
       8 . A delivery pump as claimed in  claim 1 , wherein the pump has outlet ducts with inlet ports constructed in the form of pressure tubes. 
   
   
       9 . A delivery pump as claimed in  claim 1 , wherein the pump casing is provided with a temperature control device. 
   
   
       10 . A delivery pump as claimed in  claim 9 , wherein for nominal operation at a centrifugal pump part-load-specific rotational speed nq TL≧0.05≦1 (l/min), the pump casing is provided with a thermal control device. 
   
   
       11 . A delivery pump as claimed in  claim 1 , wherein a seal is arranged between the impeller chamber and the radial impeller or a shaft of the radial impeller. 
   
   
       12 . A delivery pump as claimed in  claim 1 , wherein torque is transmitted to the radial impeller via a hermetically sealed magnet-coupled drive. 
   
   
       13 . A delivery pump as claimed in  claim 1 , wherein shaft of the rotary impeller is received in a bearing mounted on the pump casing, a heat exchanger casing or in a bearing housing. 
   
   
       14 . A delivery pump as claimed in  claim 1 , wherein the delivery pump is constructed as a modular block assembly. 
   
   
       15 . A delivery pump as claimed in  claim 1 , wherein said drive runs at constant speed to deliver a constant amount of liquid. 
   
   
       16 . A delivery pump as claimed in  claim 1 , wherein the drive speed is adjusted to deliver a metered amount of liquid.