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BELL SYSTEM TECHNICAL JOURNAL 



The die pulls and power required to draw copper wire of any size are 

 determined by referring to the chart, Figs. 10 and 11, applicable for Tung- 

 sten Carbide and Diamond Dies respectively. 



Fig. 



0.3 0.4 0.5 0.8 I 2 3 4 5 6 8 10 20 30 40 50 



AREA DIFFERENCE IN THOUSANDTHS OF A SQUARE INCH 



10 — Constants for determination of die pulls for tungsten carbide dies drawing 



copper 



0.00! 0.002 0.005 0.0! 0.02 0.05 0-1 0.2 0.5 LO 



AREA DIFFERENCE IN THOUSANDTHS OF A SQUARE INCH 



Fig. 11 — Constants for determination of die pulls for diamond dies drawing copper 



In using these charts the diameters of wire being drawn from and to are 

 selected. The difference in areas represented by these diameters is de- 

 termined, the curve is then chosen in the range of this difference, and by 

 reading up from this difference to the proper range curve, the constant can 

 be determined per .0001 sq. in. area reduction, which, when multiplied 



