US3705694A

US3705694A - Method of and an apparatus for reclaiming metal from scrap wire and cable

Info

Publication number: US3705694A
Application number: US94385A
Authority: US
Inventors: John L Slocum
Original assignee: JOHN L SLOCUM
Current assignee: JOHN L SLOCUM
Priority date: 1970-12-02
Filing date: 1970-12-02
Publication date: 1972-12-12
Anticipated expiration: 1989-12-12

Abstract

An apparatus and a method for reclaiming scrap metal from insulated cables or wires. The insulated wires are chopped into short lengths and subjected to high squeezing pressure between a pair of hard surfaces to crush the casings and destroy the integrity thereof. During the squeezing, the metal pieces are somewhat flattened and the pieces of casing are forced apart, exposing the metal. The metal pieces then fall away or are knocked away from the respective pieces of casing. The metal and casing pieces are then segregated from each other.

Description

PATENTEB man 12 I972 3. 7 O5 694 SHEET 1 BF 2 PATENTED DEC 1 2 I972 SHEET 2 BF 2 METHOD OF AND AN APPARATUS FOR RECLAIMING METAL FROM SCRAP WIRE AN CABLE This invention relates to a reclaiming process and apparatus and more particularly to reclaiming scrap metal from insulated electrical cables or wires to salvage the interior conductor metal from its insulating casing.

Recovery of metal, usually copper or aluminum, from scrap wire or cable, hereinafter referred to as wire, has been performed by burning the insulation casing from the wire. Such burning is objectionable as its pollutes the air, destroys the casing, and may adversely affect the metal.

A so-called cold process for recovery of the wire metal and'casing is also known in which the wire is chopped into very fine pieces which are granular in size, and then the casing is separated from the metal by a subsequent shaking or screening operation, like threshing. This chopping of the wire into such very fine pieces that most of the casing will no longer remain on the interior metal, particularly if shaken or vibrated, is not'altogether successful as a sizeable percentage of the chopped wire granules still retain an outer casing and must be reprocessed or discarded. The reprocessing involves putting the unseparated material through the chopping process again to produce smaller particles. Even this is not entirely successful as after the particles have been made to small for further processing, some still have metal attached to pieces of casing. This latter can be sold only as low grade scrap.

Chopping of the wire into such fine granular pieces requires many cuttings of the wire, which necessarily results in a low rate of throughput. The most serious disadvantages, however, relate to blade wear, occasioned in large measure by pieces of steel in the wire scrap, such as messengers. The cutting is done by chopping blades which must be sharpened or replaced each work shift. Sharpening of course wears the blades away. The blocks or anvils against which the blades strike also wear or break with use. This is an important cost, but more important is that the wearing of the blades slows the process and on occasion brings it to a halt. As the blades become dull, they do not cut sharply. The dull cuts produce pieces of wire of fishhook shape that are difficult to process, making it more difficult to separate the metal from the insulation. The cuts by dull blades result in many incomplete cuts, requiring more cuts to produce small enough pieces, requiring a lower throughput. If the operator is not careful to reduce throughput, the process chokes up and most be stopped to clean out the machinery. Worst of all, the repeated cutting with dull blades generates so much heat from friction that the granules actually melt down, resulting in a fused mass which can be cleaned out only with great difficulty and at great expense. It requires careful control of the process in order to operate at a fast enough rate to be economical without operating so fast as to cause the machinery to have to be closed down entirely for taking corrective measures.

Further, very fine particles are difficult to handle in certain operations. For example, it is difficult to separate particles of metal powder from pieces of casing by air flotation as many particles of powdered metal flow with the casing and are transported to scrap. Some refining processes are designed to use nuggets of metal,

and a portion of fine particles is lost up a stack when they are present in the metal being refined.

Also, in this known process, segregation of the metal and casing is achieved in part with water separator means in which the plastic casing is carried away by flotation and metal is collected on the bottom of the separator. Such water separators are costly to build and run, and the water process is relatively messy and may produce wet, slippery and unsafe working conditions. While such a cold and wet process has some advantages over the burning process, it requires considerable personnel and a relatively high capital investment.

Accordingly, a general object of the invention is to provide an improved method and apparatus for reclaiming metal and/or the insulation plastic from scrap wire.

Other objects and advantages of the invention will A become apparent from the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a diagrammatic view of an apparatus for I practicing the method for reclaiming scrap electrical conductor wire and/or its casing;

FIG. 2 is an enlarged view of a piece of insulated wire before squeezing;

FIG. 3 is a diagrammatic illustration of easing pieces and pieces of metal of the wire of FIG. 2 after they have been squeezed and separated; and

FIG. 4 illustrates another embodiment of the invention.

As shown in the drawings for purposes of illustration, the invention is embodied in an apparatus 1 for removing from wires or cables 2 their tough, flexible, outer casings 3 and to reclaim the metal 5 comprising their interior electrical conductors. The casing materials may also be reclaimed. The casing materials are usually made of plastic such as polyethylene, polyvinyl chloride or a combination of these or other plastics and, in some instances, rubber or some other elastomeric material. Sometimes the insulation is fibrous, as paper. The metal is usually a malleable copper. In accordance with the present invention and the preferred method, these scrap wires 2, which are usually long, entangled, bent and kinked, are chopped into convenient lengths or pieces. These chopped wire pieces are then squeezed with sufficient pressure to crush the surrounding casing 3 and expose the interior wire metal 5 along substantially the entire length of each piece with the metal 5 being deformed into metal pieces 9 and the easing into casing pieces 11 (FIG. 3) detached from the metal pieces 9. The metal pieces 9 and the casing pieces 11 are then segregated from each other and collected.

The preferred manner of squeezing the chopped wire pieces to separate the casing and metal materials of the insulated wire is to insert the chopped wire pieces into the nip of a pair of counter rotating squeeze rolls, preferably of hardened steel, which have hard outer cylindrical surfaces disposed closely adjacent each other and to exert sufficiently high pressure on the easing that the latter is crushed so as to be severed along at least one continuous line on each side of the wire .to release the wire metal 5. At the same time, depending upon the relative diameter of the conductor, the metal pieces 9 are flattened to a greater or lesser degree, preferably just slightly.

Referring now in greater detail to the individual elements of the illustrated apparatus 1, scrap wire is often collected and made available for reclamation in large bales in which are accumulated various lengths of insulated wire having different diameters and often'with different kinds of easing materials, such as, for example, polyethylene or polyvinyl chloride plastics. The wires 2 are usually bent and kinked within the bale and are entangled with one another. Wires 2 from the bales are conveyed on a conveyor 13 to a chopping station 14 at which a chopping means 15, chops the wires into relatively large pieces 16. The preferred chopping means includes arotating drum 17 having bar shaped cutters 18 rotatable past a fixed bed blade or block 19 to chop the wires into' relatively long lengths. Preferably the wires '2 are chopped into pieces 16 having lengths which result inmost of the wires being discrete-pieces, i.e., non-entangled and separable from 1 each other. The chopping means may be a cutting unit about 3 h feet long and 2 feet in diameter with five cutting blades 18 driven by a motor 20. Obviously the cuts are more than a foot apart; however, the cut wires are carried around by the blades 18 and recut and recut until they are small enough to fall through a screen 21. The screen may comprise a rz-inch plate drilled to provide l-inch openings, thus passing wire pieces that are about 1 inch long and smaller as well as somewhat longer pieces passing through when they are aligned with a hole or have a curled up portion passing through a hole.

The pieces 16 are conveyed by a conveyor 23 to a hopper 25. On the way it is preferable to remove iron and steel pieces, that would otherwise wear or damage subsequent equipment or contaminate the final product. Such pieces are often present from the messengers common in cables. Such pieces are conveniently removed magnetically, as by a magnetized roll 24 associated with conveyors 26 and 28. The pieces are preferably agitated in the hopper to keep them in a fluent state. The agitation may be by air flow or shaking to prevent clumps or large accumulations of the pieces 16 which would interfere with subsequent operations. The pieces fall from the hopper 25 to a second chopping station 27 at which a second chopping means 29 chops the wire into smaller pieces. It has been found suitable to use two choppers at this station each about inches long about about 1 15 feet in diameter and comprising a rotating drum 31 driven by a motor 32 and having five cutting blades 33 and a fixed bed blade 35. The outlet from each of the choppers at the second chopping station '27 is covered by a screen 37 having smaller openings than those of the first screen 21, e.g., three-eighths inch. The pieces 16 are further out by the chopping means 29 into smaller pieces 39, which are recycled by the blades 33 until they are small enough to fall through the screen 37. The chopped wire pieces 39 may be about one-half inch in length with a number of random-sized smaller pieces as cut off by chance. However, for the reasons given above, relatively few are as short as the very short chopped wire granules formed in the prior art, which had lengths comparable to the diameters of the wires.

From the chopping station 27, the chopped wires 39 fall onto conveyor 41 whereby they are conveyed into a hopper 43 wherein the pieces may be kept fluent by air flow or mechanical agitation. From the hopper 43, the

chopped wires fall onto a flow spreader which may comprise a fluted piece of sheet metal, with the flutes fanning out in the direction of flow, thereby causing the chopped wires 39 to fall relatively uniformly over a relatively wide area. The chopped wires 39 then fall between a pair of

hard rolls

47, 49 having hard, relatively unyielding surfaces.

The squeeze rolls 47 and 49 are preferably formed of hardened steel and have sufficiently large diameters as to provide surfaces which will frictionally grip the wire pieces and carry them into and through the nip while squeezing casing and metal. The squeeze rolls 47 and 49 define at the closest adjacent portions of their peripheral surfaces a gap which is less in dimension than the diameter of the wire metal 5 of the smallest diameter being processed for reclamation. It is to be recognized, however, that an occasionalvery small diameter wire might be included in thescrap and might pass through the nip without being detached from its casing; however, such an incidental happening does not detract from the fact that substantially all of the wire will have casings and wire metals detached from each other after passing through the nip. Further, it has been found that the squeezing operation often loosens the casing from the interior conductor even when the conductors are to small to permit the casing to be split, thus permitting subsequent separation, particularly where the squeezed wire passes through a cutter. Preferably, the gap between squeeze rolls at the nip is sufficiently narrow to assure some flattening of the wire metal 5 thereby assuring that the casingmaterial is being crushed completely through to expose the interior metal and to destroy the integrity of the annular casing in which the metal wire is captured. The squeeze rolls 45 and 47 are relatively massive. It has been found suitable to use rolls 20 inches in diameter and 3 feet long, weighingabout 1 ton apiece. They are mounted for rotation by a motor 46 in respective blocks. 48 and 50 which are relatively immovably mounted so as to maintain the desired gap in the nip. Rotation at a rate of 228 RPM has been found suitable. The squeezing which herein is acompressing of the wires between opposing surfaces may be accomplished by other means than a pair of squeeze rolls, but the latter are preferred.

In accordance with the present invention, the difficult problem of removing tough, non-rigid casings from wire metal is achieved by compressing the wire pieces 39 with sufficient force that the casing 3 is squeezed on diametrically opposite sides of the wire to a point where the integrity of the annular casing is destroyed at both places. More specifically, the casing is annular in cross-section and elongated and is usually a softer material than the interior conductor metal 5 On the other hand, the hardened steel squeeze rolls have surfaces which are considerably harder than either the casing or the interior conductor metal, which is usually malleable copper or aluminum. The squeeze rolls frictionally contact opposite sides of the casing and apply increasing compressive forces to the frictionally held portions of the casing while carrying the same inwardly into and through the nip between the squeeze rolls. Such compressive forces on the frictionally gripped portions of easing cause great lateral deformation and movement of adjacent non-frictionally gripped portions of the casing. Stated differently, the gripped portions of the casing. Stated differently, the portions of the casing at the sides of the frictionally gripped portions are literally being crushed or extruded laterally outward as the strength of the easing material is exceeded by the forces applied to the casing by the rolls within the nip. This results in a severing of the surrounding casing to expose the internal wire on both sides, and a squeezing outward of the casing from the conductor metal 5. As the casing material is not usually bonded to the wire metal 5 with any adhesive or bonding agent, the split, deformed and squeezed casing is usually readily separated from the wire. Simultaneously, the wire metal 5 is also undergoing compression being at least slightly flattened with an increase in area within the nipof the squeeze rolls. This also aids in the separation of the casing from the metal.

The resulting casing chips 11 and wire metal pieces 9 discharging from the nip of the squeeze rolls 47 and 49 are segregated from each other at a segregating station 51, preferably without the use of water as used in prior art process. Water separators suffer from the disadvantages of being costly to operate and having difficult working conditions. Even when water tables are used, it is usually possible to use a relatively inexpensive one.

Although many of the metal pieces 9 may be free of easing pieces 11 as they leave the nip, it is important to approach 100 percent efficiency, leaving practically no metal inthe scrap and practically no pieces of casing in the salvaged metal. This assures a high quality product with little loss of valuable metal to scrap; To assure that substantially all of the metal pieces 9 are free of easing pieces 11, the squeezed pieces are rapped sharply to knock apart any pieces that are stuck together after squeezing. Conveniently, this may be done by a rotating paddle wheel or fan 53 having blades 55 which strike the pieces sharply and knock any metal pieces free from casing pieces. The squeezed material falls from the nip between

rolls

47 and 49 against the moving blades 55. The pieces are thereby driven sharply against a plate 54 where any pieces of metal 9 still having pieces of casing adhering thereto are knocked free. The metal pieces 9 and the pieces of casing 11, free from one another, are carried by a vibratory metering conveyor 56 to the segregating station 51, which may comprise a conventional segregator 57 where the denser metal pieces 9 are segregated from the lighter casing pieces 11 by blowing, sucking and vibrating. It may take the form of a vibrating screen 60 inclined upwardly in the direction of flow and transversely of flow. It is vibrated in the direction of flow. This causes the denser pieces of metal to move preferentially upward along the screen until they are discharged at the end through a chute 58 into a receptacle S9. The lighter pieces of casing are preferentially levitated by a blast of air from a conduit 61 below the table and are sucked away through a conduit 63 above the table It may be mentioned that because the plastic casing is cut into two pieces for each piece of inner wire, the casing pieces are lighter and therefore more easily sucked from the metal pieces without lifting any substantial portion of small metal particles. The separated pieces are also of a shape more readily levitated than the tubular pieces; Those casing pieces not sucked up through the conduit 63 settle near the lower end of the segregator 5,7 and fall off the lower end through a chute 64. in

either case, the pieces of casing are then scrapped or reclaimed as the case may be.

There may be some particles that are not segregated as either casing pieces or metal pieces. These fall from the segregator 57 intermediate its ends and fall through a chute 65. These may be further processed, as by being passed through the process a second time. An alternative or additional manner of segregating the casing chips 1 1 from the wire pieces 9 is to subject the casing chips and metal pieces to an electric charge. This preferentially charges the chips of insulation. The charged plastic chips are then electrostatically attracted from a conveyor which carries both the casing chips and the metal pieces.

A modified apparatus'is shown in FIG. 4 wherein the fan 53 is eliminated and the chopping mean 29 is used for the function of knocking the metal pieces 9 from their associated casing pieces 11 as well as for the aforementioned function of cutting the wires into smaller pieces. With the elimination of the fan 53, the squeeze rolls 47 and 49 are repositioned so that the output from the hopper 43 falls directly onto the vibratory conveyor 56 whence it is conveyed to the segregator 57'. A substantial portion of this output comprises pieces of metal with insulation adhering to them, these being the chopped pieces of wire that have not'been squeezed. These pieces of metal with casing adhering thereto are not so dense as the metal pieces along yet are more dense than the pieces of easing alone. They, therefore, are not drawn off in the conduit 63, nor do they climb the segregator 57 to the top. Rather, provided the segregator is suitably disposed in a wellknown manner, they move apart way up the segregator 57 before falling off the side of the segregator through the chute 65. The chute 65 directs the metal pieces with casing attached onto a conveyor 67 which conveys them into a hopper 69, whence they 'fall onto the flow spreader 45 and then between the squeeze rolls 47 and 49.

in passing through the nip between the squeeze rolls 47 and 49, the casing is split and the inner metal deformed, as described above. Then instead of being directed onto a fan, the squeezed product is conveyed by a conveyor 70 into the hopper 2 ,,Whence they fall into the chopping means 29 where the metal is knocked free of the casing. This time, when the metal pieces reach the segregator 57, they are vibrated to the end of the segregator and fall into the receptacle 59, the easing pieces being levitated into the conduit 63 or falling into the chute 64. The newly added unsqueezed pieces from the chopping means 29 fall into the chute 65 and are conveyed to the squeeze rolls 47 and 49 for squeezing and detaching of the casing pieces from the interior metal.

It will be seen from the foregoing that the preferred method includes the steps of providing insulated wire in pieces relatively long relative to granules and squeezing the wire pieces with sufficient pressure to destroy the integrity of the annular casing to the extent that the casing is or may be detached from the metal pieces. The metal pieces are then segregated from the casing pieces. The particular apparatus used for performing the segregation may take various forms, such as those above described or others known in the art.

In the foregoing it will be seen that this invention solves the difficult problem of separating the casing from the metal of wires without the necessity of burning the casing. The squeezing of the casing from the wire metal provides a process which is relatively inexpensive and eliminates the necessity for chopping the wire into such fine granular pieces as in prior methods.

While a preferred embodiment has been shown and described, it will be understood that there is no intent to limit the invention by such disclosure but, rather, it is intended to cover allmodifications and alternate constructions falling within the spirit and scope of the invention as defined in the appended claims.

What is claimed is: l. A method of reclaiming materials from'insulated wire having interior conductor metal and asurrounding electrically insulating casing comprising the steps of:

) squeezing each piece of insulated wire between hard surfaces on a pair of rotating cylindrical rolls rotating at substantially the same peripheral velocity with squeezing pressure without any substantial grinding of the pieces and with sufficient pressure to extrudethe surrounding casing to destroy its integrity and expose the interior'conductor metal alongsubstantially the entire length of each piece, and segregating the resulting metal pieces from the casing pieces. '2. A method in accordance with claim 1, wherei said segregating comprises separating said metal pieces from said casing pieces by a gravity separating means. 3. A method in accordance with claim 2, in which said casing pieces are lifted from said metal pieces by a pressure differential.

4. A method in accordance with claim 1, wherein the product of squeezing is rapped to detach casing pieces from their associated metal pieces.

5. A method in. accordance with claim 1, wherein said segregating comprises selectively electrically charging said casing pieces, and electrostatically attracting the charged casing pieces from the .metal pieces. I

6. A method of recovery of material from scrap insulated wire having an outer encircling casing and an interior conductor metal, including the steps of chopping insulated wire into pieces, inserting the chopped wire pieces into the nip of a pair of rotating squeeze rolls having peripheral surfaces rotating at substantially the same velocity and harder than the conductor metal, applying sufficient squeezing force within the nip of said rolls without any substantial grinding of the pieces to breach the encircling casing, detaching the casing pieces from the respective metal pieces, and segregating the metal pieces from the detached pieces of casing.

7. A method in accordance with claim 6, in which the segregating step segregates the squeezed'product into metal pieces, detached pieces of casing, and chopped wire pieces in which casing adheres to the metal, and in which the latter class of product is inserted into said nip and the squeezed product is returned to the chopping step for detaching adherent casing pieces from their associated metal pieces.

8. An apparatus for reclaiming material from insulated wire and for separating interior conductor metal from a surrounding insulating casing, said apparatus comprising: means for chopping the insulated wire into d'screte ieces means ors ace in idco dwire pieces comprising a pair of har si n tanti ali y s mooth surfaced counterrotating cylindrical rolls. having peripheral-surfaces rotating at substantially the same velocity'and having a hip therebetweeninto which are inserted the chopped wire pieces, said rolls being spaced apart by a distance less than the diameter of the metal conductor of substantially all wire -to be processed for reclamation to split said casing and thereby expose said conductor metal 'along substantially its entire length, and means for segregating the resulting metal pieces and casing pieces from each other.

v9. A method of reclaiming materials from substantially cylindrical pieces of electrical wirehaving interior conductor metal and a substantially cylindrical surrounding electricallyinsulating casing of plastic comprising the steps of: squeezing the cylindrical pieces between hard cylindrical rolls having peripheral surfaces rotating at substantially the same velocity and applying squeezing pressure without any substantial grinding of the pieces sufficient to split and extrude the surrounding cylindrical plastic casing to destroy its integrity and to form flattened surface areas on the interior conductor metal, and segregating the resulting metal pieces from the casing pieces.

10. An apparatus in accordance with claim 8, including means for rapping the squeezed product to detach casing pieces from their associated metal pieces.

11. An apparatus in accordance with claim 10, wherein said means for segregating segregates the squeezed product into metal pieces, detached pieces of casing, and metal pieces to which casing adheres, and in which said means for rapping includes conveyor means for returning said metal pieces to which casing adheres to said means for chopping. I

12. An apparatus in accordance with claim 11, wherein .said means for squeezing is disposed in the return path from said means for segregating to said means for chopping.

13. A method of recovery of material from scrap insulated wire having an outer encircling casing and an interior conductor metal, including the steps of: chopping insulated wire into pieces with some pieces of conductor metal being separated from its associated case during the chopping, segregating the metal pieces from the casing pieces and from the chopped wire pieces, inserting the chopped wire pieces into the nip of a pair of rotating squeeze rolls having peripheral surf faces rotating at substantially the same velocity and harder than the conductor metal, applying sufficient squeezing force without any substantial grinding-of the pieces within the nip of said rolls to breach the encircling casing, detaching the casing pieces from the respective metal pieces, and segregating the squeezed metal pieces from the detached squeezed pieces of casing and returning any insulated wire pieces to the squeezing rolls for another squeezing operation.

14. A method in accordance with claim 13 including the steps of using an air pressure differential to remove light insulating casing materials and using an air vibrating table to form discrete streams of metal and casings for collection and a stream of wire pieces for squeezing.

* a a a a t nnnr

Claims

2. A method in accordance with claim 1, wherein said segregating comprises separating said metal pieces from said casing pieces by a gravity separating means.
3. A method in accordance with claim 2, in which said casing pieces are lifted from said metal pieces by a pressure differential.
4. A method in accordance with claim 1, wherein the product of squeezing is rapped to detach casing pieces from their associated metal pieces.
5. A method in accordance with claim 1, wherein said segregating comprises selectively electrically charging said casing pieces, and electrostatically attracting the charged casing pieces from the metal pieces.
6. A method of recovery of material from scrap insulated wire having an outer encircling casing and an interior conductor metal, including the steps of chopping insulated wire into pieces, inserting the chopped wire pieces into the nip of a pair of rotating squeeze rolls having peripheral surfaces rotating at substantially the same velocity and harder than the conductor metal, applying sufficient squeezing force within the nip of said rolls without any substantial grinding of the pieces to breach the encircling casing, detaching the casing pieces from the respective metal pieces, and segregating the metal pieces from the detached pieces of casing.
7. A method in accordance with claim 6, in which the segregating step segregates the squeezed product into metal pieces, detached pieces of casing, and chopped wire pieces in which casing adheres to the metal, and in which the latter class of product is inserted into said nip and the squeezed product is returned to the chopping step for detaching adherent casing pieces from their associated metal pieces.
8. An apparatus for reclaiming material from insulated wire and for separating interior conductor metal from a surrounding insulating casing, said apparatus comprising: means for chopping the insulated wire into discrete pieces, means for squeezing said chopped wire pieces comprising a pair of hard, substantially smooth surfaced counterrotating cylindrical rolls having peripheral surfaces rotating at substantially the same velocity and having a nip therebetween into which are inserted the chopped wire pieces, said rolls being spaced apart by a distance less than the diameter of the metal conductor of substantially all wire to be processed for reclamation to split said casing and thereby expose said conductor metal along substantially its entire length, and means for segregating the resulting metal pieces and casing pieces from each other.
9. A method of reclaiming materials from substantially cylindrical pieces of electrical wire having interior conductor metal and a substantially cylindrical surrounding electrically insulating casing of plastic comprising the steps of: squeezing the cylindrical pieces between hard cylindrical rolls having peripheral surfaces rotating at substantially the same velocity and applying squeezing pressure without any substantial grinding of the pieces sufficient to split and extrude the surrounding cylindrical plastic casing to destroy its integrity and to form flattened surface areas on the interior conductor metal, and segregating the resulting metal pieces from the casing pieces.
10. An apparatus in accordance with claim 8, including means for rapping the squeezed product to detach casing pieces from their associated metal pieces.
11. An apparatus in accordance with claim 10, wherein said means for segregating segregates the squeezed product into metal pieces, detached pieces of casing, and metal pieces to which casing adheres, and in which said means for rapping includes conveyor means for returning said metal pieces to which casing adheres to said means for chopping.
12. An apparatus in accordance with claim 11, wherein said means for squeezing is disposed in the return path from said means for segregating to said means for chopping.
13. A method of recovery of material from scrap insulated wire having an outer encircling casing and an interior conductor metal, including the steps of: chopping insulated wire into pieces with some pieces of conductor metal being separated from its associated case during the chopping, segregating the metal pieces from the casing pieces and from the chopped wire pieces, inserting the chopped wire pieces into the nip of a pair of rotating squeeze rolls having peripheral surfaces rotating at substantially the same velocity and harder than the conductor metal, applying sufficient squeezing force without any substantial grinding of the pieces within the nip of said rolls to breach the encircling casing, detaching the casing pieces from the respective metal pieces, and segregating the squeezed metal pieces from the detached squeezed pieces of casing and returning any insulated wire pieces to the squeezing rolls for another squeezing operation.
14. A method in accordance with claim 13 including the steps of using an air pressure differential to remove light insulating casing materials and using an air vIbrating table to form discrete streams of metal and casings for collection and a stream of wire pieces for squeezing.