Abstract: An aerosol can piston and system, employing an aerosol can with a sidewall which is necked in at the bottom and a low mass piston with recessed, depending legs. The piston has a lower skirt portion, the outermost diameter of which is slightly smaller than the diameter of the inner wall of the can above the necked-in portion. The legs depending from the piston have an effective outer diameter somewhat less than the inside diameter of the lower necked-in portion of the can sidewall and depend sufficiently downward to sit on the can bottom countersink while maintaining the skirt of the piston at a level just above the level at which the can sidewall necks inwardly. The legs thus stabilize the piston and prevent tipping and canting. In an alternative embodiment the piston also includes a plurality of vertical columns protruding from its sidewall to further stabilize the piston.

Abstract: A method and apparatus for making a necked container are disclosed wherein a sheet material is formed into a generally cylindrical tubular member and the adjacent longitudinally extending edges of the sheet are butt welded. The welded tubular member is progressively necked-in over a dome-shaped surface of a single mandrel provided within the welded tubular member. The free end of the necked end portion of the tubular member is trimmed and curled to form a necked container body.

Abstract: A method and apparatus for making a necked container are disclosed wherein a sheet material is formed into a generally cylindrical tubular member and the adjacent longitudinally extending edges of the sheet are butt welded. The welded tubular member is progressively necked-in over a dome-shaped surface of a single mandrel provided within the welded tubular member. The free end of the necked end portion of the tubular member is trimmed and curled to form a necked container body.