US2318614A - Art of producing wire - Google Patents

Description

May 11, 1943. w. E. LEONARD ART OF PRODUCING WIRE Filed June 6, 1940 [men/07':

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Patented May 11, 1943 UNITE-D {STATES PATENT OFFICE ART OF PRODUCING WIRE William E. Leonard, Worcester, Mass., assignor to The American Steel and Wire Company of New Jersey, a corporation of New Jersey Application June 6, 1940, Serial No. 339,193 2. Claims. (01. 205-21) This invention relates generally to the art of producing wire, but it is particularly concerned with expediting the production of thoroughly clean wire or bright annealed wire, from rod.

The customary way to produce thoroughly clean or bright annealed wire from rod is to lubricate it with soap and draw it through dies until the desired reduction in its diameter is obtained. Sometimes the wire is limed but, in all events, when its drawing is completed, this being known as dry-drawing, its surface is contaminated with the dry-drawing lubricant to such an extent that it cannot be sold as being thoroughly clean and if the wire were placed directly in a bright annealing furnace it could not possibly come out of the furnace with a. bright finish. To overcome this difhculty it is customary to clean the wire with acid prior to its being sold as thoroughly clean or placed in the bright annealing furnace, this introducing added cost and trouble to the production of this article.

According to the present invention, rod, this being a hot rolled product, or wire which has been drawn one or more drafts from a rod, is limed, if desired, and is then dry-drawn, the usual soap lubricant being used. Instead of coiling the wire thus drawn from the rod, or wire, it is immersed in liquid for a sufllcient time to thoroughly wet the dry-drawing lubricant contaminating its surface. At this point the surface of the wire is fairly clean, but it is far from being thoroughly clean or so clean as to permit its being bright annealed.

To eliminate the necessity for acid cleaning the wire to completely cleanse its surface, the wire is next given at least one pass through a wetdrawing die, or, in other words, the wire is wetdrawn at least once with at least suflicient severity to thoroughly strip it of everything that might be contaminating its surface. It-is to be understood that wet-drawing consists in wetting the wire with a slightly acid solution containing a copper or tin salt, the copper or tin being uniformly plated on the wire and serving, in conjunction with the liquid, to lubricate the wire during its passage through the wet-drawing die. However, the acidity of the wet-drawing solution is very slight and the latter does not function, merely by reason of its being slightly acid, to clean the wire. This solution may be the liquid mentioned in the preceding paragraph. The wetdrawn wire can now be sold as thoroughly clean or placed in a bright annealing furnace so that it comes out of the furnace in a satisfactorily bright and clean condition. When sold as unannealed, thoroughly clean wire, it has the attractive appearance of liquor finished wire but the important thing is that it is thoroughly clean.

The various steps that have been outlined can be carried out continuously. That is to say, the wire leaving its dry-drawing phase and continuously traveling, may bepassed repeatedly through a relatively small tank containing the wetting liquid which softens the dry-drawing lubricant. Continuously leaving this liquid the wire may go directly through the wet-drawing die, the wire being continuously coiled upon leaving this wet-drawing die and the coils of wire so formed transferred to the bright annealing furnace, if desired, or sold as thoroughly clean, unannealed wire. It is suggested that the wire be coiled, but it is conceivable that a satisfactory continuous bright annealing furnace may be used. In such cases the wire would be passed continuously through the furnace from the wet-drawing die when annealing is desired.

The liquid used to wet the dry-drawing lubricant prior to its being wet-drawn may be liquor such as is used for wet-drawing, this being, as has been mentioned, a slightly acid solution of a copper or tin salt. A suitable solution consists of copper sulphate in water to which is added a liquor made by iermentating rye mill, the fermentation of this grain providing the acidity. It sometimes may be necessary to regulate the acidity with very small amounts of sulphuric acid. When such a liquor is used as scouring or wetting medium, it not only thoroughly wets, and possibly to some extent removes, the dry-drawing lubricant but it also functions to copper plate the wire whereby to condition it for the wetdrawing step.

It is again repeated that this liquor cannot function to completely remove all of the drydrawing lubricant, as is accomplished by the prior art method ofsoaking the wire for prolonged periods in relatively strong acid solutions or the continuous and substantially instantaneous wetdrawing step of the present invention.

The accompanying drawing illustrates apparatus suitable for carrying out the various steps that have been described herein, Figure 1 being an elevation of the apparatus while Figure 2 shows a section of a bright annealing furnace.

The drawing shows the end of a continuous wire drawing machine I, which may be constructed according to the prior art, provided with a plurality of dies I preceded in one or more instances by a soap dish l the latter containing the dry-drawing lubricant or soap and the wire .thereby during its passage through the die. It

is to be understood that the wire stock fed the dry-drawing machine I is generally in the form of hot rolled rod or wire which is, sometimes, limed.

Upon leaving the dry-drawing, the wire, marked W in the drawing, passes over a sheave 2, the wire being formed into a plurality of loops. by wrapping around a drum 3 and the latter immersing the wire in the wetting or scouring liquor in a tank 4. This liquid may be conventional wetdrawing liquor as has been previously explained.

Upon leaving the immersing drum 3, the wire, carrying the now thoroughly wetted remains of the dry-drawing lubricant goes through the wetdrawing die 5 to a draw block 5 which applies the tension to the wire necessary to carry it from the dry-drawing machine I. The wire is snubbed about the block 6 by a draw-out drum 6" and goes from there to a take-up or coiler I.

All of the apparatus operates in a continuous fashion and does not necessitate handling of the wire after initial threading, the rod or wire going continuously through the dry-drawing machine and ending up on the coiler 1 without being handled by the workmen.

The coils of wire produced by the take-up I may be subsequently placed in a bright annealing furnace I. It is understood, of course, that the bright anneal must be carried out by both heating and cooling the wire coils in an atmosphere that is suillciently nonoxidizing to prevent oxidation of the wires. In the case of the bell-type furnace illustrated, the coils of wire are placed on a base 8" and covered with a shield 8 which is flooded with the nonoxidizing gas. The furnace 8 is in the form of a bell which may be dropped over the cover l during the heating cycle and removed during the cooling cycle. When cooled to nonoxidizing temperatures, the wire coils may be exposed by removing the cover 8, at which time it will be found that the wire has a satisfactorily bright finish which is comparable, if not superior, to that obtained by acid cleaning the dry-drawn wire in the manner taught by the prior art.

One of the biggest advantages oi the present invention is its ability to handle continuously traveling wire moving at a speed as high as is consistent with the operation of the dry-drawing machine I. When acid cleaning is resorted to instead of the wet-drawing step of the present invention, it is necessary to coil the wire leaving the dry-drawing machine and to keep it immersed in the acid cleaning solution for prolonged periods of time, this slowing production and making trouble for the workmen, the handling of the coils necessarily involving a great deal of manual labor.

As previously explained. .the wire may be sold as unannealed, thoroughly clean wire. In such a case, the furnace l, of course, is not used.

I claim:

. 1. In the art of producing wire, the steps of applying dry. drawing lubricant to wire stock,

drawing the stock to produce wire with its surface contaminated by the dry drawing lubricant,

wetting the wire with a metallic salt to wet the wire during the wet drawing.

2. In the art of producing wire, the steps of applying dry drawing lubricant to wire stock,

drawing the stock to produce wire with its sur-' face contaminated by the dry drawing lubricant. wetting the wire with a metallic salt to wet the dry drawing lubricant contaminating its surface and to plate its surface with the metal or the salt, and wet drawing the wire while wetted with the metallic salt to produce wire with its surface clean, the metal plated on the wires surface and the metallic salt solution serving to lubricate the wire during the wet drawing, the wire being subsequently annealed in a nonoxidizingatmosphere to produce bright annealed wire with a satisfactory bright finish.

3. In the art of producing wire, the steps of applying dry drawing lubricant to wire stock,

drawing the stock to produce wire with its surface contaminated by the dry drawing lubricant, wetting the wire with a metallic salt to wet the dry drawing lubricant contaminating its surface and to plate its surface with the metal of the salt, and wet drawing the wire while wetted with the metallic salt to produce wire with its surface clean, the metal plated on the wires surface and the metallic salt solution serving to lubricate the wire during the wet drawing, the named steps being carried out in succession on a single continuously moving length of wire stock traveling at a speed consistent with good dry drawing practice.

WELIAM E. LEONARD.

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