Air suspension piston

Abstract

The invention relates to an air suspension piston, with the air suspension piston being tube shaped and being made of aluminium. The air suspension piston is formed by a longitudinal-seam welded tube made from an aluminium alloy, and the tube has been longitudinal-seam welded without any weld metal.

1 . An air suspension piston, with the air suspension piston being constructed in the shape of a tube and being made of aluminium, wherein the air suspension piston is a longitudinal-seam welded tube made from an aluminium alloy.  
     
     
         2 . An air suspension piston according to  claim 1 , wherein the tube has been longitudinal-seam welded without any weld metal.  
     
     
         3 . An air suspension piston according to  claim 1  or  2 , wherein the aluminium alloy is a self-hardened alloy.  
     
     
         4 . An air suspension piston according to one of  claims 1  to  3 , wherein the wall thickness of the tube is 1.5 mm.  
     
     
         5 . An air suspension piston according to one of  claims 1  to  4 , wherein the longitudinal-seam welded tube has been formed to the geometry of the air suspension piston by drawing-in and enlargement operations.  
     
     
         6 . An air suspension piston according to one of  claims 1  to  4 , wherein the longitudinal-seam welded tube has been formed to the geometry of the air suspension piston by hot forming operations.  
     
     
         7 . An air suspension piston according to one of  claims 1  to  4 , wherein the longitudinal-seam welded tube has been formed to the geometry of the air suspension piston by not forming operations using internal high-pressure.  
     
     
         8 . An air suspension piston according to one of  claims 1  to  6 , wherein the weld seam of the tube is raised between −0.1 and +0.1 mm.