Developments in the manufacture of copper wire

This paper describes a new copper rod and wire mill located at the Western Electric Company's Plant at Chicago. It includes a brief survey of the copper rolling and wire drawing art at the time the investigation was started; a summary of tests made in varying the practice In rod rolling and wire drawing; and an outline of the work done by the Western Electric Company engineers in developing and designing new types of wire drawing machinery. The rod mill is converting 225 pound wire bars into 1/4″ rod in fourteen instead of the usual eighteen passes. This is accomplished by making heavier reductions in the first four passes while the copper is hot. The new wire mill incorporates many novel features, and the wire drawing machines are more compact in design and of considerably higher speed than those in general use. The design of the wire mill was undertaken following a comprehensive survey of wire drawing processes and equipment used in this country and abroad. Part of this survey consisted of a study of the manufacture of diamond dies, it having been found that dies suitable for high speed drawing required a differently shaped “approach,” a better polish, and a shorter “land,” than those which were available for low speed work. The economies in floor space and plant investment due to the use of more compact and higher speed machinery are outlined. Some of the outstanding features in plant arrangement which contribute to more efficient operation are discussed in the concluding pages.