Apparatus and methods for forming an elongated product

A die for deforming a workpiece so as to form a product composed of one or more substantially adjacent, individual articles, the product having a cross-sectional shape which differs from that of the workpiece, said die comprising:

• a die body having aperture means extending axially therethrough about a central axis of the aperture means, said aperture means having an entrance end and including at least one aperture, with the aperture means providing an overall aperture configuration corresponding to said overall cross-sectional shape of the product to be formed, and with the aperture means having a maximum transverse dimension, smaller than a corresponding dimension of the die body, in a direction perpendicular to said central axis;
• and
• wall means which converge from an outer periphery of the die body toward said entrance end of the aperture means, said wall means having a surface bounded by the entrance end of said aperture means, and by a closed curve substantially centered on said central axis and displaced axially, and radially outwardly, from the aperture means, said closed curve following said outer surface of the die body, said surface having a shape defined substantially by a number of ridges linerarly interconnected selected arcuate divisions about the periphery of the closed curve with corresponding peripheral divisions about the entrance end of the aperture means, and by relatively recessed areas between the closed curve and the entrance end of the aperture means intermediate adjacent ones of said ridges, said recessed areas serving to direct various elements of the workpiece forced through the die linearly toward respective corresponding peripheral divisions about the entrance end of the aperture means.

A method of deforming a workpiece so as to form a product composed of one or more substantially adjacent, individual articles, the product having an overall cross-sectional shape which differs from that of the workpiece, said method comprising:

• a. aligning the workpiece with an axis of a die having aperture means extending axially therethrough from an entrance end of the aperture means, the aperture means including at least one aperture and providing an overall aperture configuration which differs from that of the workpiece and corresponds to the overall cross-sectional shape of the product to be formed;
• and
• b. forcing the workpiece axially against said die and through said aperture means;
• while
• c. building up pressure smoothly and continuously within the material of the workpiece by causing each surface element of the workpiece to move along a single continuous, linear path, directed substantially radially and axially inwardly, as the workpiece is forced against said die and into said entrance end of the aperture means, and simultaneously causing said surface elements to follow a continuous, substantially smoothly flowing surface pattern from element to adjacent element surrounding the entrance end of the aperture means;
• and while
• d. causing substantially all of the material of the workpiece first to attain said overall cross-sectional shape of the product in substantially the same cross-sectional plane of the die at the entrance end of the aperture means.