Hydraulic positioning assembly for cold rolling tubes

Abstract

A cold rolling apparatus includes a forming roll which applies a forming load to a tube when cold rolling the tube, and a hydraulic positioning assembly including a positioning roller disposable for initial contact with a tube surface and arranged to apply a positioning load to the tube. A hydraulic circuit is coupled to the forming roll and to the hydraulic positioning assembly such that the positioning load is related to the forming load. A face plate mounted for movement with the forming roll, and the positioning roller is mounted to the face plate. The face plate is coupled to a piston of the hydraulic positioning assembly for movement with the piston relative to the forming roll. The piston is housed within a cylinder body coupled to a guide block which is coupled to the forming roll. The forming roll is an outside roll, and the cold rolling apparatus includes two positioning rollers.

What is claimed is:  
     
         1 . A cold rolling apparatus, comprising: 
 a forming roll which applies a forming load to a tube when cold rolling the tube, and    a hydraulic positioning assembly including a positioning roller disposable for initial contact with a tube surface and arranged to apply a positioning load to the tube.    
     
     
         2 . The cold rolling apparatus of  claim 1  further comprising a hydraulic circuit coupled to the forming roll for applying the forming load to the tube, the hydraulic positioning assembly being coupled to the hydraulic circuit such that the positioning load is related to the forming load.  
     
     
         3 . The cold rolling apparatus of  claim 1  wherein the hydraulic positioning assembly includes a face plate mounted for movement with the forming roll, and the positioning roller is mounted to the face plate.  
     
     
         4 . The cold rolling apparatus of  claim 3  wherein the hydraulic positioning assembly includes a piston and the face plate is coupled to the piston for movement with the piston relative to the forming roll.  
     
     
         5 . The cold rolling apparatus of  claim 4  wherein the hydraulic positioning assembly includes a cylinder body housing the piston, the cylinder body being coupled to a guide block which is coupled to the forming roll.  
     
     
         6 . The cold rolling apparatus of  claim 1  wherein the forming roll is an outside roll.  
     
     
         7 . The cold rolling apparatus of  claim 1  including two positioning rollers.  
     
     
         8 . A cold rolling apparatus, comprising: 
 an outside roll which applies a forming load to a tube when cold rolling the tube,    a hydraulic positioning assembly including a face plate mounted for movement with the outside roll and positioning rollers mounted to the face plate, the positioning rollers being disposable for initial contact with a tube surface and arranged to apply a positioning load to the tube, the hydraulic positioning assembly further including a cylinder body coupled to the outside roll and housing a piston, the face plate being coupled to the piston for movement with the piston relative to the outside roll, and    a hydraulic circuit coupled to the outside roll for applying the forming load to the tube, the hydraulic positioning assembly being coupled to the hydraulic circuit such that the positioning load is directly related to the forming load.    
     
     
         9 . A method of applying a positioning load to a tube during cold rolling, comprising: 
 placing the tube between an inside roll and an outside roll, placing a positioning roller against a surface of the tube,    applying a forming load to the tube with the outside roll through a hydraulic circuit, and    applying a positioning load to the tube with the positioning roller through the hydraulic circuit such that the positioning load is related to the forming load.    
     
     
         10 . A hydraulic assembly for controlling movement of a positioning roller assembly of a cold rolling apparatus, comprising: 
 a hydraulic cylinder body configured for coupling to a forming roll of the cold rolling apparatus for movement therewith,    a piston housed by the cylinder body for movement relative to the cylinder body, the piston being adapted for coupling to the positioning roller, and    a hydraulic line having a first end coupled to the hydraulic cylinder and a second end coupled to a fitting.