Method for making one-piece can bodies utilizing draw-redraw forming of flat-rolled sheet metal while maintaining control of orientation and movement of cup-shaped work product throughout a can-making line, comprising in combination the steps of
- providing continuous-length flat-rolled sheet metal of predetermined thickness gage coated on both its planar surfaces with an organic coating, such organic coating surfaces being coated with draw-lubricant;
- establishing a horizontally oriented sheet metal travel path for longitudinal movement of such flat-rolled sheet metal in the direction of its continuous length into and out of a blanking and cupping station;
- feeding such sheet metal in substantially planar form in the direction of its continuous length by providing for cyclic longitudinal movement of such sheet metal through such blanking and cupping station for repetitious blanking and cupping operations during cyclic interruptions in longitudinal movement of continuous-length sheet metal along such sheet metal travel path;
- carrying out a blanking and cupping operation which includes:
- cutting a circular blank of predetermined diameter from sheet metal, then
- draw forming such cut blank into a cup-shaped work product having its open end oriented upwardly by relative movement from opposite planar surfaces of such cut blank of a draw punch with respect to a draw die defining a draw cavity into which such sheet metal is drawn,
- such drawn work product having a closed end wall, a cylindrical configuration unitary side wall extending toward its remaining opposite open end of such drawn cup and a compound curvilinear transition zone joining such closed end wall and cylindrical side wall,
- such cylindrical side wall being symmetrically spaced from the drawn work product central longitudinal axis which is perpendicular to the geometric center of such planar end wall,
- controlling relative movement between such draw punch and draw die so as to provide unitary flange metal extending radially outwardly with respect to such central longitudinal axis around the periphery of such open end of the drawn work product,
- such flange metal lying in a plane which is substantially normal to the central longitudinal axis of the drawn work product, and
- disposing such drawn work product for movement from such blanking and cupping station with its closed end wall in such sheet metal travel path;
- then
- pneumatically moving such drawn work product while separating the travel path of the scrap sheet metal from which a blank has been cut from the travel path of the drawn work product to direct such work product onto a work product can line for controlled movement toward a redraw station,
- electrostatically lubricating interior and exterior surfaces of the drawn work product before redrawing while such work product is being controllably moved along such work product can line;
- and thereafter
- carrying out a redraw operation on such lubricated cup-shaped work product to decrease the diameter of its closed end wall and increase the height of its unitary side wall to form a redrawn cup,
- such redrawing operation being carried out while such work product is oriented closed-end up utilizing simultaneous movement in opposite directions along such central longitudinal axis of a redraw punch and a redraw die defining a redraw cavity into which such work product is redrawn,
- controlling movement of such redraw punch and redraw die along such central longitudinal axis during such redrawing operation to present flange metal at the open end of such redrawn cup,
- such flange metal extending radially outwardly at the open end of such redrawn cup in a plane which is normal to the central longitudinal axis of such redrawn cup,
- such flange metal at the open end of such redrawn cup being disposed in such work product line at completion of such redraw operation;
- and
- moving such redrawn cup from such redraw station closed-end up with such redrawn flange metal disposed in such work product can line.