The drawing of various shaped cups along with related blanking and piercing were clearly described and illustrated in a 14-article series in the Tool Engineer, 1948-49. The correct, elegant, explanatory diagrams need to be exhibited in commemoration of J.W. Lengdridge (as well as enlightenment for the uninitiated). In deep drawing a circular cup from a flat sheet, a narrow rectangle of the sidewall is produced from a triangular segment of the original blank (excepting the portion in bottom) that has been compressed circumferentially while lengthening and thickening more near the top. The control of the wrinkle-preventing die-face hold-down, pressures, lubrication, dimensions of blanks and shapes for both circular (pots, food cans) and rectangular (sinks, boxes) blanks are illustrated. The possibility of multiple draws for very deep cylinders combined with sidewall ironing has been applied with great success in beverage cans. The entire cycle, including base dome formation and top reduction for addition of sealing lids is illustrated. As well as for drawing, press-hold downs and punch-die clearances are explained for blanking and punching. The problems of earring in anisotropic sheet are bemoaned and the development of hot rolling schedules for isotropic strip is explained.
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