Manufacturing a curved measuring tube for a vibratory measurement pickup

Abstract

For manufacturing a measuring tube from a tube section, first a solid forming core serving during the bending for stabilizing the cross section of the tube section is formed within the lumen of the tube section from a first fill substance and a second fill substance included therein. The first fill substance is a solidified liquid, especially wax, fat or water, having a melting temperature lower than a melting temperature of the tube section, while the second fill substance is, at least in a normal condition, an essentially pourable, especially grainy and/or powdered, loose material, especially granulated material, sand or the like, having a melting temperature which is higher than the melting temperature of the liquid. Following the creating of the forming core, the tube section is bent by the introduction of a bending force acting at least sectionally externally on the tube section. Finally, the forming core is desolidified within the lumen of the bent tube section by effecting the melting of the fill substance in the form of solidified liquid within the bent tube section.

1 - 25 . (canceled)  
   
   
       26 . A method for manufacturing a bent measuring tube for a vibration-type measurement pickup, esp. a Coriolis mass flow measurement pickup, into a desired form using a tube section of predetermined cross section and lumen, which method comprises the steps of: 
 forming, within the lumen of the tube section to be bent, a solid forming core of a first fill substance and a second fill substance included therein, said forming core serving to stabilize the cross section of the tube section during bending;    bending the tube section through introduction of a bending force that acts at least sectionally externally on the tube section; and    desolidifying the forming core within the lumen of the bent tube section, wherein:    a solidified liquid, esp. wax, fat or water, that has a melting temperature lower than the melting temperature of the tube section, serves as the first fill substance, and an at least normally essentially pourable, esp. grainy and/or powdered, loose material, having a melting temperature that is higher than the melting temperature of the liquid, serves as the second fill substance; and    the step of desolidifying the forming core within the lumen of the bent tube section includes a step of melting the first fill substance situated in the form of solidified liquid within the bent tube section.    
   
   
       27 . The method as claimed in  claim 26 , wherein: 
 the step of forming the forming core within the lumen of the tube section includes the following steps: introducing at least a part of the first fill substance in the form of molten liquid, as well as at least a part of the second fill substance, into the lumen of the tube section; and causing the first fill substance, in the form of molten liquid, to solidify within the lumen of the tube section.    
   
   
       28 . The method as claimed in  claim 26 , wherein: 
 the first fill substance in the form of liquid is poured into the tube section for the purpose of forming the forming core within the lumen of the tube section.    
   
   
       29 . The method as claimed in  claim 26 , further comprising the step of: 
 liquid-tight sealing at least one end of the tube section.    
   
   
       30 . The method as claimed in  claim 26 , wherein: 
 a momentarily pourable, loose material is used as the second fill substance; and    the step of introducing a second fill substance includes a step of filling pourable, especially grainy and/or powdered, loose material into the lumen of the tube section.    
   
   
       31 . The method as claimed in  claim 30 , wherein: 
 the filling at least of a part of the first fill substance into the lumen of the tube section occurs before and/or during the filling of the second fill substance into the lumen of the tube section.    
   
   
       32 . The method as claimed in  claim 30 , wherein: 
 the filling of at least a part of the second fill substance into the lumen of the tube section occurs before and/or during the filling of the first fill substance into the lumen of the tube section.    
   
   
       33 . The method as claimed in  claim 30 , further comprising the step of: 
 densifying the filled second fill substance within the lumen of the tube section, esp. by shaking and/or tamping.    
   
   
       34 . The method as claimed in  claim 26 , further comprising the step of: 
 removing the molten first fill substance from the lumen of the bent tube section.    
   
   
       35 . The method as claimed in  claim 26 , wherein: 
 liquid is allowed to flow out of the bent tube section to remove the melted first fill substance from the lumen of the bent tube section.    
   
   
       36 . The method as claimed in  claim 26 , wherein: 
 the step of desolidifying the forming core within the lumen of the bent tube section includes a step of loosening the second fill substance contained in the lumen of the bent tube section.    
   
   
       37 . The method as claimed in  claim 36 , further including the step of: 
 removing loose, esp. pourable, second fill substance from the bent tube section.    
   
   
       38 . The method as claimed in  claim 26 , wherein; 
 the step of removing the second fill substance from the bent tube section includes a step of allowing loose material to flow from the bent tube section.    
   
   
       39 . The method as claimed in  claim 26 , wherein: 
 the second fill substance is used in a 9:1 ratio, or more, with respect to the first fill substance.    
   
   
       40 . The method as claimed in  claim 26 , wherein: 
 the first fill substance is a liquid that solidifies at a temperature less than 100° C., especially at a temperature around 0° C.    
   
   
       41 . The method as claimed in  claim 26 , wherein: 
 the first fill substance is at least partially water.    
   
   
       42 . The method as claimed in  claim 26 , wherein: 
 the first fill substance is at least partially wax, oil or fat.    
   
   
       43 . The method as claimed in  claim 26 , wherein: 
 the second fill substance is at least partially a grainy material, especially one having spherical particles.    
   
   
       44 . The method as claimed in  claim 26 , wherein: 
 the second fill substance is at least partially a powder.    
   
   
       45 . The method as claimed in  claim 26 , wherein: 
 the second fill substance is at least partially mineral.    
   
   
       46 . The method as claimed in  claim 26 , wherein: 
 the second fill substance is at least partially organic.    
   
   
       47 . The method as claimed in  claim 26 , wherein: 
 the second fill substance is at least partially metallic.    
   
   
       48 . The method as claimed in  claim 26 , implemented using a press mold that is matched to the desired form of the measuring tube to be manufactured and that has a punch and a cavity, wherein the step of bending the tube section through introduction of a bending force that acts at least sectionally externally on the tube section includes the following steps: inserting the tube section, equipped with the forming core, into the opened press mold and positioning it between punch and cavity; and closing the press mold and bending the tube section by means of a relative motion of punch and cavity towards one another.  
   
   
       49 . The method as claimed in  claim 48 , further comprising the steps of: 
 opening the press mold after the bending of the tube section; and    removing the bent tube section from the opened press mold.    
   
   
       50 . Use of a bent tube section produced by means of the method of  claim 26  as a measuring tube of a vibration-type measurement pickup, especially a Coriolis mass flow measurement pickup.