WIRE AND WIRE DRAWING. Wire is defined as metal elongated into a long thread like form of thicknesses varying from one and one-quarter inches to less than 1/1000 of an inch. each size uniform throughout the piece; these threads having usually the cylindrical form. but they may be square, flat, oval or ribbed. in which case they are known as 'shaped wire • The process by which wire is formed is known as drawing. Essentially, this consists in forci bly pulling a suitably prepared piece of the metal thus worked through a series of holes made in hardened steel dies set in a draw-plate, and which successively diminish in diameter. In this way the cross section of the wire is gradually reduced to that of the last hole through which it is drawn; its length, mean while, being correspondingly and greatly in-. creased. As a consequence, wire can be pro duced only from such metals as are susceptible in this way of being pulled out or extended by stretching Into rods. Such metals are said to be drawable, or to have the property of ductility This property is not to be confounded with that of malleability, namely, that in virtue of which a metal is laminable, or admits of being ham mered or rolled into thin plates; since the same metal is often malleable and ductile in very different degrees. Thus, while gold possesses both these properties in an extreme, and probably in the highest known degree, iron is ductile in a degree far beyond that in which it is malleable_ and with tin and lead the reverse is true. Of the familiarly known metals, the most ductile, and in the order named, are gold, silver, plati num, steel, iron, nickel, copper, brass, zinc, tin and lead; while some of the ordinarily biotic metals when made perfectly pure, as bismuth_ are said to possess very high ductility. In early times metals were brought to the filamentous form only by means of beating them under the hammer into thin plates, then dividing these by cutting instruments into narrow strips, and finally rounding with the hammer and 61e. The earliest known mention of 'wire drawers' and 'wire millers,' as those who produced wire by drawing were variously called, occurs in 1331 and 1360, in the histories respectively of Augs burg and Nuremberg, the previous accounts be ing only of 'wire smiths,' or those who fabri cated wire with the hammer. The change from the old to the new method was accomplished, or very soon followed, by the introduction of a machine by which wire was successfully pro duced without direct aid of the hand; this ma chine, probably the invention of one Rudolf, of Nuremberg, was impelled by water power. The precious metals appear to have been the first subjected to this process— brass and iron not until some time later. White wire. or blanch iron wire, is mentioned in a list of articles not to he imported into England in 1463; and in 1484 both iron and latter (fine brass) wire arc similarly named. Up to 1565 English iron wire
was drawn by hand only. and was of so poor a quality that most of that used in the country. and also wool cards and other articles involving the of wire, were imported. As late as )unit) there was no wire mill in England; but in 111.11 year patents were granted to manu facture wire ui Fligland In the history of United States industries the first mention of sure draining occurs in the annals of the town i Lynn, Mass., where it is recorded that in Nathaniel Robinson, a pe :ioned the court for aid in carrying on his ::ade. This was refused at the time, but later :he court authorized the purchase of instru ments and tools for this industry and granted a 'onus for its encouragement. In 1775 a wire factory was established by Nathaniel Niles in Norwich. Conn., and in 1788 a large wire mill was running in Dedham, Mass., making wire for cards and fishhooks. Pittsburgh had a wire factory in 1791. In 1834, however, there were only three wire mills in all the United States, and their total output was 15 tons for that year. It is worthy of note that one of these riginal three mills — that at Worcester, Mass. — is now the largest wire producing plant in the world.
The 1914 census of manufactures reported that in that year there were 99 establishments drawing wire in the United States; 54 being strictly manufacturers of wire and 45 being party should consist of 32 workers, if possible exclusive of non-commissioned officers. Form the party in two ranks and number them in threes, both front and rear ranks. The left file is not numbered. For the sake of explana tion letters are given to these parties of three as follows: Duties of Parties A and B go out almost simultaneously. Party A drives the first row of pickets and so needs a maul. The maul man should be tall. One man mauls, one supplies the pickets, one paces the three yards and holds the pickets for driving. Keeping close up so as not to lose the pickets, comes party 13 with a coil of barbed wire, a pair of wirecutters and two pairs of hedging gloves. All wire parties carry similar equip rolling-mills which drew wire in addition to their other business. Of the entire number 68 drew iron and steel wire: 28, copper wire; 28, brass wire; and 16, wire of other metals. Their equipment totaled 51,181 blocks and their total capacity was 3,2352,000 tons of wire per annum. The 1914 output of these mills amounted to 2.435,530 tons of steel and iron wire; 138,924 tons of copper wire; 19,491 tons of brass wire; 106 tons of bronze wire; 375 tons of German salver wire; and 2.981 tons of wire of other metals- The aggregate value of the year's pro duction was $174600,546.
The modern system of wire drawing is de scribed under WIRE, MANUFACTURE OF.