NEW COPPER WIRE DRAWING PLANT 



101 



The constant horsepower requirement for uniform tension when con- 

 verted into torque shows that the torque increases as the wire on the reel 

 builds up due to the lengthening of the radius arm. 



The decreasing horsepower requirement to overcome windage and fric- 

 tion when converted into torque shows that the torque decreases with this 

 build-up of wire due to the slowing down of the reel when using a uniform 



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AMERICAN WIRE GAUGE NUMBER 



Fig. 6 — Tension in wire due to stress set up at wire speed of 12,000 F.P.M. 



speed of drawing. This decrease will be at a faster rate than the increase 

 resulting from tension. 



The calculated torques when plotted for the different sizes of wire within 

 the scope of the machine show curves gradually diverging as the reel de- 

 creases in speed. To simplify the electrical control it was found these 

 curves could be made parallel and still be within the allowable variation of 

 wire tension and the required tolerances of the supplier of the electrical 

 equipment. It was decided to select as the base curve that condition which 



