Method of forming a tubular member

Abstract

A method for roll-forming a tubular member is provided. The method includes providing a roll-forming machine having a pair of rollers and a forming roller adjacent the pair of rollers. Further, cutting a strip of sheet metal to form a segment having free leading and trailing ends extending between a predetermined length; feeding the segment between the pair rollers; calculating the thickness of the segment via feedback from the pair of rollers; automatically adjusting the position of the forming roller in response to the determined thickness of the segment; advancing the segment between the pair of rollers and against the forming roller to form an annulus; and forming a weld joint between the free ends.

What is claimed is: 
     
         1 . A method for roll-forming a tubular member, comprising:
 providing a roll-forming machine having a pair of rollers including a feed roller driven on a fixed feed roller axle and a pinch roller supported on an axle that is moveable toward and away from the feed roller axle, and a forming roller adjacent the pair of rollers;   cutting a strip of sheet metal to form a segment having free leading and trailing ends extending between a predetermined length;   feeding the segment between the pair of rollers;   moving the pinch roller over a measured distance into abutment with the segment to a predetermined pressure and calculating the thickness of the segment via the predetermined pressure and the measured distance of the pinch-roller;   automatically adjusting the position of the forming roller in response to the thickness of the segment calculated via the measured distance and pressure feedback from the pinch roller;   advancing the segment between the pair of rollers and against the forming roller to form an annulus; and   forming a weld joint between the free ends.   
     
     
         2 . The method of  claim 1  further including performing the cutting by blanking the sheet metal with a cutting blade and forming the leading end of the segment having a predetermined radius of curvature with the cutting blade having a leading cutting edge and a trailing edge, the cutting blade having a radiused surface extending between the leading cutting edge and the trailing edge, wherein the radiused surface of the cutting blade forms the predetermined radius of curvature. 
     
     
         3 . The method of  claim 2  further including forming the predetermined radius of curvature having substantially the same radius of curvature as the annulus.  4 , The method of  claim 2  further including forming the predetermined radius extending over a distance substantially equal to the distance between tangent points of the pair of rollers and forming roller against which the segment abuts. 
     
     
         5 . The method of  claim 1  further including automatically moving the forming roller to compensate for the thickness of the segment to provide the annulus with a predetermined inner diameter via the position of the forming roller. 
     
     
         6 . The method of  claim 1  further including automatically moving the forming roller to compensate for the thickness of the segment to provide the annulus with a predetermined outer diameter via the position of the forming roller. 
     
     
         7 . The method of  claim 1  further including providing the roll-forming machine having a plurality of rollers separate from the pair of rollers and the forming roller. 
     
     
         8 . The method of  claim 7  further including automatically adjusting the position of the plurality of rollers in response to the determined thickness of the segment. 
     
     
         9 . The method of  claim 1  further including expanding the annulus in a sizing process. 
     
     
         10 . The method of  claim 9  further including spin forming an annular flange on said cumulus simultaneously with the sizing process. 
     
     
         11 . The method of  claim 10  further including forming at least one notch in the cumulus. 
     
     
         12 . The method of  claim 10  further including forming at least one opening in the annulus.