Tool for locally forming a workpiece

Abstract

A forming or re-rounding machine has a pair of concentric inner and outer rings supported with a gap between the rings. The support of the rings provides for both axial and rotational movement. A can or shell having a section to be formed, or a damaged portion for re-rounding, is inserted into the gap. Hydraulic rams are mounted in a radial pattern into the outer edge of the inner ring and the inner edge of the outer ring, facing the gap. The inner and outer rings can be oriented so that the hydraulic rams in each ring can be directly opposed to the hydraulic rams in the opposing ring, or alternatively, can be offset from adjacent hydraulic rams in the opposing ring. In a vertically oriented embodiment, the forming or re-rounding machine has a pair of concentric rings suspended from a crane or I-beam support with a gap between the rings.

What is claimed is:  
     
         1 . A machine for forming a workpiece, comprising: 
 an inner ring;    an outer ring concentric with and surrounding the inner ring about an axis to form a gap between the inner and outer rings, the gap for receiving the workpiece between the inner and outer rings;    at least a pair of hydraulic rams, at least one hydraulic ram mounted to each of the inner and outer rings so as to extend into the gap; and    a support connected to each of the inner and outer rings for moving the inner and outer rings back and forth along the axis and rotating the inner and outer rings about the axis to align at least one of the at least a pair of hydraulic rams over an area of the workpiece.    
     
     
         2 . The machine according to  claim 1 , wherein each hydraulic ram comprises an hydraulic cylinder connected to a ram head.  
     
     
         3 . The machine according to  claim 1 , wherein the inner and outer rings are oriented so that the at least one hydraulic ram mounted to the inner ring and the at least one hydraulic ram mounted to the outer ring are directly opposed.  
     
     
         4 . The machine according to  claim 1 , wherein the inner and outer rings are oriented so that the at least one hydraulic ram mounted to the inner ring and the at least one hydraulic ram mounted to the outer ring are offset from each other.  
     
     
         5 . The machine according to  claim 1 , wherein the inner and outer rings are offset from each other.  
     
     
         6 . The machine according to  claim 1 , further comprising means for rotating the workpiece.  
     
     
         7 . The machine according to  claim 1 , wherein the inner ring comprises at least a pair of inner rings and the outer ring comprises at least a pair of outer rings, the at least a pair of inner and outer rings being arranged in at least a pair of sets of concentric inner and outer rings forming gaps therebetween, the at least a pair of sets connected together and having the gaps aligned with each other for receiving the workpiece.  
     
     
         8 . A machine for providing a cylindrical workpiece with a round circumference, comprising: 
 an inner ring;    an outer ring concentric with and surrounding the inner ring to form a gap between the inner and outer rings, the gap for receiving the workpiece between the inner and outer rings;    at least a pair of hydraulic rams, at least one hydraulic ram mounted to each of the inner and outer rings so as to extend into the gap; and    a vertically displaceable support connected to each of the inner and outer rings for moving the inner and outer rings up and down and rotating the inner and outer rings to align at least one of the at least a pair of hydraulic rams over an area of the workpiece.    
     
     
         9 . The machine according to  claim 8 , wherein each hydraulic ram comprises an hydraulic cylinder connected to a ram head.  
     
     
         10 . The machine according to  claim 8 , wherein the inner and outer rings are oriented so that the at least one hydraulic ram mounted to the inner ring and the at least one hydraulic ram mounted to the outer ring are directly opposed.  
     
     
         11 . The machine according to  claim 8 , wherein the inner and outer rings are oriented so that the at least one hydraulic ram mounted to the inner ring and the at least one hydraulic ram mounted to the outer ring are offset from each other.  
     
     
         12 . The machine according to  claim 8 , wherein the vertically displaceable support comprises rods attached to the inner and outer rings and connected to cables.  
     
     
         13 . A machine for providing a cylindrical workpiece with a round circumference, comprising: 
 an inner ring;    an outer ring concentric with and surrounding the inner ring to form a gap between the inner and outer rings, the gap for receiving the workpiece between the inner and outer rings;    at least a pair of hydraulic rams, at least one hydraulic ram mounted to each of the inner and outer rings so as to extend into the gap; and    a horizontally displaceable support connected to each of the inner and outer rings for moving the inner and outer rings right and left and rotating the inner and outer rings to align at least one of the at least a pair of hydraulic rams over an area of the workpiece.    
     
     
         14 . The machine according to  claim 13 , wherein the outer ring is segmented.  
     
     
         15 . The machine according to  claim 14 , wherein the outer ring comprises at least one segment, the at least one segment only partially surrounding the workpiece.  
     
     
         16 . The machine according to  claim 13 , wherein each hydraulic ram comprises an hydraulic cylinder connected to a ram head.  
     
     
         17 . The machine according to  claim 13 , wherein the inner and outer rings are oriented so that the at least one hydraulic ram mounted to the inner ring and the at least one hydraulic ram mounted to the outer ring are directly opposed.  
     
     
         18 . The machine according to  claim 13 , wherein the inner and outer rings are oriented so that the at least one hydraulic ram mounted to the inner ring and the at least one hydraulic ram mounted to the outer ring are offset from each other.