US3828601A - Method and apparatus for producing a finished joint between ends of wires, rods and the like - Google Patents

Abstract

A method and apparatus for producing a finished joint between the ends of wires or rods of like material and sectional size and shape by completely upsetting joined workpieces, thereby to thoroughly remove all heat-affected metal and to effect the establishment of bonds having properties or characteristics which equal or exceed those of the parent material, and which, as completed by the method and apparatus, preserve the uniformity of size, shape and smooth finish of the wires or rods at and adjacent the joint without added manual operations, and to the extent required to avoid having the joint interfere with further operations, such as coating, twisting into cable, insulating or further drawing of the wire or rod.

Description

United States Patent i191 Tessmann a Aug. 13, 1974 METHOD AND APPARATUS FOR 3,259,969 7/1966 Tessmann 29/487 PRODUCING A FINISHEDJOINT BETWEEN glurphree ozmus ENDS OF WIRES RODS AND THE LIKE 3,597,958 8/1971 Gross 72/331 lnventor: Alfred H. Tessmann, 13761 Joyce Dr., Largo, Fla. 33540 Filed: July 19, 1973 Appl. No.: 380,575

Related US. Application Data Continuation of Ser. No. 259,495, June 5, 1972, abandoned.

US. Cl 72/334, 29/487, 219/97 Int. Cl B211 15/08 Field of Search 29/481, 493, 487, 33 A;

References Cited UNITED STATES PATENTS 5/1872 Seward 3/1959 Evans 7/1960 Harris et al. 10/ 1 963 Primary Examiner-Richard J. Herbst 5 7] ABSTRACT A method and apparatus for producing a finished joint between the ends of wires or rods of like material and sectional size and shape by completely upsetting joined workpieces, thereby to thoroughly remove all heat-affected metal and to effect the establishment of bonds having properties or characteristics which equal or exceed those of the parent material, and which, as completed by the method and apparatus, preserve the uniformity of size, shape and smooth finish of the wires or rods at and adjacent the joint without added manual operations, and to the extent required to avoid having the joint interfere with further operations, such as coating, twisting into cable, insulating or further drawing of the wire or rod.

21 Claims, 18 Drawing Figures PATENTEBMIBIBIW I $828,601

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METHOD AND APPARATUS FOR PRODUCING A FINISHED JOINT BETWEEN ENDS OF WIRES,

RODS AND THE LIKE CROSS-REFERENCE This application is a continuation of my co-pending application, Ser. No. 259,495, filed June 5, 1972 and entitled Method and Apparatus for Effecting Molecular Flow Butt Welded Joints Between Ends of Wires, Rods and the Like now abandoned.

SUMMARY OF THE INVENTION The invention disclosed herein is an improvement of that shown and described in my US. Pat. No. 3,259,969, issued July 12, 1966 for METHOD OF MAKING BUTT WELDED JOINTS.

In the apparatus depicted in my aforementioned US. Pat. No. 3,259,969, electrode chucks are utilized adjacent the ends of wires or rods which are to be adjoined by fusing the metal under heat. These chucks have smooth internal surface portions in which gripping areas are peripherally serrated for firmly gripping the surfaces of the wires or rods in order to transmit thereto the forces required for deforming the metal to effect work hardening thereof during the production of the butt welded joint.

The outward taper of the smooth inner chuck end surface portions produces a small, but objectionable bulge in the wire surface at the position of the weld. This increased cross section is necessary to produce a work hardened area at the joint to approach the original strength values of the wire at the joint. However, the heated zone of metal extends axially beyond this joint because of the heat generated along both electrode chucks during the fusing operation. This axially extending heated zone leaves core metal, in particular, in an annealed and softened state to the detriment of desired strength factors which are present in the parent material. Also, the severe marks left by the serrations in the electrode chucks are objectionable, as are the changes in internal strength characteristics produced thereby.

In contrast to my aforementioned patented method and the apparatus shown in the patent, tapered inner end surfaces of the die openings adjacent the weld area are designedly and purposely avoided in the apparatus disclosed herein. The dies of this invention are cold, non-electrode dies. They are quite meticulously ground and polished principally to provide areas of substantial length to engage and maintain the originally intended cross-sectional shape, size and straightness of the wire regions on both sides of the heat-affected zone axially adjacent the pre-welded or pre-worked joint. The dies on the opposite sides of the joint also are carefully aligned and supported to establish linearity of the wire at, and on both sides of this heat-affected zone. As herein disclosed, the metallurgical properties of the finished joint which are ultimately produced by the upsetting and hardening during formation of the finished joint are controlled and conformed to produce at least the initial metallurgical characteristics of the wire. This is done by selectively establishing the relative travel of the opposed dies on opposite sides of the heat-affected zone in order to completely eliminate and remove all metal, previously annealed or heated during the heat welding, fusing, or joining of the abutting wire ends. Thus, in further contrast to the teachings in my aforementioned patent, where work hardening is utilized to attempt restoration of parent metal properties, the presently disclosed apparatus and method eliminates the heat and strength-affected metal. Moreover, as the outward ends of the presently disclosed dies complete the upset and extrusion of heat-affected metal, the extreme pressure build up produces sufficient work hard ening that the strength of the finished joint actually cxceeds the strength of the parent metal.

Structurally considered, the dies which maintain the straightness, alignment and sectional roundness of the wire on opposite sides of the heat-affected zone, are separate from, and separately actuatable with respect to the gripping jaws through which axial force is transmitted to the workpiece during formation of the finished joint. Also, the dies of the apparatus herein disclosed have integral stop surfaces which limit the movements of opposed dies toward one another, thereby preventing damage to other working surfaces of the dies.

As another feature, the clamping jaws which grip the workpieces for applying operational force thereto are self-adjusting for various workpiece sizes within a prescribed range of sectional sizes. Furthermore, the clamping jaws engage opposed surfaces of the workpieces and are extended along such workpiece surfaces sufficiently to materially limit deformation and marring of the workpiece surfaces during the application of adequate operational force thereto.

It is an object of this invention to provide a method and apparatus for quickly producing finished joints between metal workpieces, such as ends of wires or rods whether in a heated condition or at ambient temperature, and which finished joints, as normally produced by the method hereof, have properties and characteristics which equal or exceed those of the parent metal and do not require additional finishing operations in order for the joined parts to be readily usable in further operations, such as drawing, coating with insulation or twisting with other wires to produce twisted cable.

This invention has for another object the provision of a method and apparatus for producing finished joints between metal workpieces which are work hardened, and wherein the amount of work hardening is subject to ready control to achieve predetermined characteristics of the metal such as tensile strength, temper, or elongation.

As a further object, this invention contemplates method and apparatus providing for the complete removal from a workpiece of all heat and strengthaffected metal resulting from any previous workpieces joining operation such as buttwelding, or fusing, thereby producing a finished joint of parent metal.

As another object, this inventionhas within its purview the provision of a method and apparatus which are particularly adapted to the preservation of the normal size, sectional shape and finish of workpiece segments at and adjacent opposite sides of the finished joint.

The invention further comprehends the provision of a method and apparatus in which the steps of the operations are adapted to be carried out selectively by manual operation, or to be accomplished in a predetermined sequence by automatic controls to effect the formation of finished joints after being manually started.

The method and apparatus of this invention have within their purview the production of finished joints The apparatus of a preferred embodiment of this invention incorporates dies which are separate and separately operable with respect to workpiece gripping elements through which operational forces are applied to the workpieces, and which dies have as purposes the maintenance and insurance of straightness, alignment and sectional shape and size of the workpieces at, and on opposite sides of a zone of heat-affected metal.

Further, in respect to the aforementioned dies, they embody opposed end surfaces which not only serve in effecting removal of excess metal from around the finished joint, but also include opposed and aligned stop surfaces of substantial section and accurately positioned to provide for close coaction of said opposed end surfaces without permitting damage thereto.

The workpiece gripping elements utilized in the apparatus of this invention have within their purview not only the minimizing of surface and internal strength damage to the portions of the workpieces gripped, but also provide for self-adjustment of the gripping action to accommodate workpieces of varying sizes within a predetermined range.

The apparatus of this invention also comprehends the provision of a readily adjustable for which extends between relatively movable parts of the mechanism to predetermine the relative initial spacing between those parts so as to include between the dies all heat-affected metal, thereby to predetermine the operational movement which occurs during the formation of the joint between workpieces.

.Other objects and advantages of this invention may become apparent as the detailed description'of the method, structure and operation proceed with reference to the accompanying drawings, wherein:

FIG. 1 is a front'elevational view of a preferred form of apparatus fo r effecting finished joints between ends of wire, rods and the like, and which apparatus is adapted to function in accordance with my preferred method for effecting the formation of such joints;

FIG. 2 is a top sectional view taken substantially at the position indicated by a line 2-2 in FIG. 1, and in the direction indicated byaccompanying arrows;

FIG. 3 is an end sectional view taken substantially at the position indicated by a line 3-3 in FIG. 1, in the direction of the accompanying arrows, and drawn to a larger scale than FIG. 1;

FIG. 4 is another end sectional view taken substantially at the position of a line 44 and in the direction of the arrows, as indicated in FIG. 1, but in this view operating parts of the mechanism areshown in different positions than in FIGS. 1 and 3;

FIG. 5 is a fragmentary front plan view of a portion of the structure illustrated in FIG. 1, drawn to a'larger scale than FIG. 1, and wherein parts are illustrated in different operating positions than in FIG. 1, and certain parts are sectionalized to show structural detail;

FIG. 6 is a fragmentary top sectional view taken substantially as indicated by a line 6-6 and accompanying arrows in FIG. 5;

FIG. 7 is a fragmentary view taken substantially as indicated by a line 77 and accompanying arrows in FIG. 1, and is drawn to a larger scale than FIG. 1;

FIG. 8 is a fragmentary sectional view taken substantially at the position indicated by a line 8-8 and in the direction of accompanying arrows, as shown in FIG. 5;

FIG. 9 is a fragmentary perspective view of wire or rod ends which have been butt-welded together. but wherein the finished joint is not yet complete;

FIG. 10 is a fragmentary perspective viewof a complete and finished joint as produced by the apparatus and method depicted herein;

FIG. 11 is a front elevational or plan view of wire or rod endsin adjacent and opposed relationship, prior to the commencement of the formation of the weld therebetween;

FIG. 12 is a view similar to FIG. 11, but depicting the wire or rod end segments after the formation of a conventional electrical butt-welded joint therebetween;

FIG. 13 is illustrative of the wire end segments of FIG. 12, disposed between open dies of the illustrated apparatus, and wherein the dies are spaced for the completion of the operations on the .wire or rod;

FIG. 14 is similar to FIG. 13, but shows one of the dies closed and the other still open;

FIG. 15 is similar to FIG. 14, but shows both dies closed relative to the wire or rod;

FIG. 16 is a view somewhat similar to FIG. 15, but additionally depicting clamps in closed position for gripping the wire or rod segments at opposite ends of the dies while the dies remain in spaced relationship on opposite sides of the initial weld, as shown in FIG. 15;

FIG. 17 is a view similar to FIG. 16 but showing the parts in different operating positions, to which they are moved for completing the formation of the joint; and

FIG. 18 isa view similar to FIG. 13, with the dies again spaced and open after the completion of the joint formation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Having reference to the accompanying drawings, wherein a preferred embodiment of this invention is depicted for illustrative purposes, the mechanism illustrated is adapted to produce finished joints between abutting workpiece ends of like metal, sectional size and shape and wherein the sectional size and shape and the smooth finish of the workpieces, as well as the metal characteristics, are maintained without added manual or finishing operations, and wherein the strength and other metal characteristics of the metal, at the joint, are comparable and compatible with those of other segments of the workpieces. Throughout the drawings, like reference numerals refer to corresponding parts.

As shown in FIGS. 1 and 2, the mechanism has a base plate 20 from which the other parts are operationally supported. A stationary support 22 is secured to the base plate 20 and projects outwardly therefrom in right angular relationship thereto; it being understood that the illustrated mechanism is constructed for normal use with the base plate 20 in a generally vertical position. At the other end of the base plate, bearing blocks 23 and 24 are secured thereto in alignment with opposite end portions of the stationary support 22, so that the stationary support 22 and the bearing blocks 23 and 24 serve as stationary mounting supports for the operational parts of the mechanism.

Double-acting hydraulic rams 25 and 26 are secured to opposite ends of the outer end surface of the stationary support 22, and project outwardly therefrom in spaced relationship to one another. In their mounted positions, the rams 25 and 26 are axially aligned with bearings 27 and 28, respectively, in the bearing blocks 23 and 24. Piston rods 29 and 30 of the rams 25 and 26, respectively, extend through suitable bearing openings 32 and 33, respectively, in the stationary support 22, and have " coaxial shaft extension 34 and 35 on the ends thereof remote from the support 22 and supported for linear sliding movement in the bearings 27 and 28, respectively. As the description progresses, it will be observed that the piston rods 29 and 30, and their respective extensions, serve as supports for other moving parts of the mechanism.

At a position spaced from the stationary support 22, and near the bearing blocks 23 and 24, a crosshead 36 is supported on the piston rods 29 and 30, through suitable bearings 37 and 38. Recesses 39 and 40 are provided in the outer face surface of the crosshead 36 near the opposite ends thereof, and in concentric relationship to the axes of the piston rods 29 and 30, respectively. The recesses 39 and 40 are of a larger diameter than the piston rods and their respective bearings in the crosshead, and serve as seats for collars 42 and 43, which are secured in position on the piston rods 29 and 30, respectively, as will be more fully described. As shown in FIG. 1, each piston rod has an end portion 44 of reduced section at the end thereof and providing a shoulder 45 on the piston rod. The end portion 44 of each piston rod is threaded, and each of the collars 42 and 43 is threaded onto its respective piston rod to abut the shoulder. Also, each of the shaft extensions 34 and 35 has an axial bore 46 in the end thereof, which is threaded onto the threaded end portion 44 of each piston rod to the extent that the end of each shaft extension abuts its respective collar in opposed relationship to the shoulders on the piston rods, thereby to secure the collars and shaft extensions in position on the ends of the piston rods, and whereby movement of the piston rods 29 and 30 toward the rams 25 and 26, respectively, effect movement of the crosshead 36 in a corresponding direction as a result of engagement of the collars 42 and 43 with the crosshead.

At the mid-region of the mechanism, die carriers 47 and 48 are mounted on, and for movements along the parallel piston rods 29 and 30. Except for some minor details, and except for the fact that in certain respects the die carriers 47 and 48 are laterally reversed in structure in order to have comparable portions in opposed relationship in reference to a plane of general symmetry therebetween, these die carriers are alike to the extent that a general description of one will suffice for both; it being understood that the die carriers are mounted in generally parallel relationship to one an other and that each performs a similar function in the operation of the mechanism.

As viewed in the drawings, as in FIGS. 1 to 7, inclusive, the structural description of the die carriers 47 and 48 will be written in particular reference to the lefthand die carrier 47, and corresponding parts of the right-hand die carrier will be designated by corresponding reference numeral having a prime mark added thereto.

In addition to being parallel, the die carriers are disposed across the piston rods 29 and 30 in substantially right-angular relationship thereto. As a basic structural part, each die carrier has a support element 49 of channel section which serves as a mounting for the other parts thereof. As disposed for use, and as viewed in FIGS. 1 and 2, side flanges 50 and 52 of the base support element 49 project outwardly from the base plate 20 and have spacer blocks 53 and 54 secured to the outer edges thereof, as by welded seams 56, along the adjacent margins of the spacer blocks and flanges. At the lower end of the die carrier 47, a mounting block 57 is secured to the outer edges of the spacer blocks 53 and 54 by welded seams, as at 58, 59 and 60. The mounting block 57 is somewhat shorter than the spacer blocks 53 and 54, and is set back from the upper end of the spacer blocks to provide surfaces 62 and 63 which serve as a seat for a die block 64.

The die block 64 has a V-notch 65 extending laterally of the side surface thereof opposite the seat surface 63, and which is exposed adjacent the outer surface of the mounting block 57. Another V-notch 66 is provided in the outer surface of the mounting block 57 in spaced relationship to the V-notch 65, and extends in substantially parallel relationship thereto. A bridge-piece 68 has angularly disposed projecting ends 69 and 70 which are spaced to extend partially into the V- notches 65 and 66 in the die block and mounting block, to secure the die block firmly against its seating surfaces when screws 72, which extend through openings 73 in the bridge-piece 68 and are threaded into threaded openings 74 in the mounting block, are tightened to secure the bridge-piece in place against the mounting block and die.

A bearing 75 is mounted in a bearing bore 76 in the mounting block 57, through which bearing the piston rod 30 extends to mount one end of the die carrier 47 for linear movement therealong, as well as to provide for movements of the piston rod therethrough. As shown in detail in FIG. 7, the bearing 75 may be held in place in the bearing bore 76 by means, such as snap rings 77 and 78, disposed in suitable peripheral grooves 79 and 80 adjacent opposite ends of the bearing bore.

At the upper end of the die carrier, a spacer and mounting block 82 is secured on the outer edges of the flanges 50 and 52 of the base support element 49, as by welded seams 83 extending along the adjacent margins thereof. At opposite sides of the mounting block 82, bearing blocks 84 and 85 are secured to the mounting block in spaced relationship, by means such as bolts 86 and 87, to serve as a support for a hydraulic ram cylinder 88, having trunnions 89 mounted in bearing openings 90 in the bearing blocks.

At the lower end of mounting block 82, spacer blocks 92 and 93 are secured to the outer edges of side flanges 50 and 52 of the base support element of. the die carrier, by welded seams, such as 94. The spacer blocks 92 and 93 extend from the edge of the mounting block 82 to the ends of the spacer blocks 53and 54, and have outer surfaces in flush relationship with those of the spacer blocks 53 and 54. At a position spaced above the mounting block 57 and below the hydraulic ram cylinder 88 and its mounting block 82, a slide block 95 is secured to the spacer blocks 92 and 93, as by welds 96 and 97, to extend across the outer surfaces of the spacer blocks 92 and 93 and along the mid-regions thereof. As in the instance of the mounting block 57, the slide block 95 has a bearing 98 mounted in a bore 99 which extends laterally thereof, which bearing is slidably mounted on the piston rod 29, whereby the piston rods 29 and 30, and the respective bearings 75 and 98, support the die carrier relative to the supporting structure and for movements along and relative to, the piston rods 29 and 30.

A yoke 100 has a connecting web portion 102 at its upper end and has arms 103 and 104 extending from the connecting portion 102 in substantially parallel relationship to one another. The yoke 100 has a width to fit slidably between the spacer blocks 92 and 93, and also has its arms 103 and 104 spaced to fit slidably over the opposed outer surfaces of the slide block 95 while the arm 104 is disposed between the spacer blocks 92 and 93. The hydraulic ram 88 is a doubleacting ram and has a piston rod 105, a reduced and threaded end portion 106 which is threaded into a threaded bore 107 in web portion 102 of the yoke to provide an operating connection therebetween.

At the end of the yoke opposite the web portion 102, a die carrier block 108 is secured thereto. The die carrier block 108 is of the same width as the yoke 100 and has notches 109 and 110 therein with a projecting portion 112 therebetween, which notches and projecting portion fit onto and between the ends of the arms 103 and 104 of the yoke and are secured in position thereon by fastening means, such as bolts 113. On its outer end, away from the end of. the yoke, the die carrier block 108 has a projecting portion 114 and provides die seating surfaces] and 116 in angular relationship to one another for the location and'mounting of a die block 117 in opposed and operative relationship with respect to the die block 64. Since the die blocks 64 and 117 are interchangeable for the accommodation of workpieces of different sizes and shapes, but must be held firmly in place during use, the die block 117 is secured in position on the die carrier block 108 in a manner similar to that utilized for the securement of the die block 64. That is, a V-notch 118 extends laterally of the outer surface of the yoke arm 108 in spaced relationship from the die carrier block end thereof. Another V- notch 119 is provided in the outer surface of the die block 117. A bridge-piece 120 has beveled ends 122 and 123 engaged in the notches 118 and 119, and is secured in place by fastening means, such as screws 124, threaded into the die carrier block 108 to secure the die block 117 in place on its seat.

In the form disclosed, the die blocks 64 and 117 are made to accommodate rod or wire of circular section and of a preselected diameter; it being understood that the dies utilized are selected to conform to the size and exterior peripheral contour or shape of the workpieces. In this instance, the die blcok 64 and the die block 117 have semicircular die grooves 125 and 126 respectively, extending thereacross, and which die grooves are ground and polished, to be straight from end to end and to provide an exact, snug fit for the normal size and shape of a workpiece 127. When the die blocks 64 and 117 are separated, as shown in FIGS. 1 and 3, a workpiece may be passed between the die blocks and placed in the die groove 125 of the lower die block. While it is not intended to be the function of diesto afford gripping action through which operating forces are applied to the workpieces, the die blocks, when brought together by the action of the ram 88 as shown in FIG. 4, do have a straightening action on the encompassed portion of the workpiece and maintain the workpiece portion fully encompassed, at its normal size andshape therein. Since the die blocks when closed would have only a minimal effect on the workpiece if the die blocks were of an axial length of only a few multiples of the workpiece diameter, it is desirable to have the die blocks at least several multiples of the workpiece diameter in length so that a substantial axial portion of the workpiece is encompassed, thereby assuring straightening significant action on the workpiece by the die blocks.

For ensuring the alignment of coacting die blocks 64 and 117, hardened and ground pins 128 and 129 are mounted and secured in position in spaced and parallel relationship in one of the die blocks, at positions displaced from the die groove, and have a snug, sliding fit in bores in the other die block, whereupon alignment and registry of the die grooves of the die blocks is ensured each time the dies are closed relative to a workpiece.

In addition to the fact that the die carriers 47 and 48 are generally similar in structure with parts in opposed relationship and mounted for movements on and relative to the piston rods 29 and 30, the coacting die blocks on each die carrier are mounted so that the lower or stationary die blocks on each die carrier are mounted in longitudinal alignment and for movements along and parallel to a longitudinal central plane. To ensure alignment of the die blocks during movements of the dies on the carriers 47 and 48 toward and from one another during the operation of the'mechanism, hardened and ground pins 130 and 132 are mounted in spaced and parallel relationship in one of the lower die blocks of the pair, and have a snug, sliding fit in bores in the other die block, whereupon, the dies of the pair are aligned longitudinally of the mechanism for movements of the dies toward one another to the closed position depicted in FIGS. 5 and 6. Thus, with the dies maintained in both lateral and longitudinal alignment, straightness, size and uniformity of section and linearity of the workpiece are maintained in the die encompassed segments, and for substantial distances during the operation of the mechanism.

The die carriers 47 and 48 are biased apart by compression springs 133 and 134, which have ends mounted .in suitable and aligned recesses in opposed surfaces of the slide blocks 95 and 95' and in the mounting blocks 57 and 57 respectively. For adjusting the normal separated spacing between the die carriers 47 and 48, as is necessary for adapting the mechanism for operation on workpieces of different sizes and to insure that all heat-affected and strengthaffected metal extending axially on either side of the joint is included between the dies so as to be completely upset and removed by them, a readily adjustable stop 135 is provided. In the form illustrated, and as shown in FIG. 1, a threaded rod 136 extends through aligned bores 137 in the mounting blocks 82 and 82' in the die carriers 47 and 48. The threaded rod 136 is normally secured in position relative to the die carrier 48 by nuts 138 and 139, which are threaded onto the rod on opposite sides of the mounting block 82' and tightened thereagainst. By changing the positions of the nuts 138 and 139, abnormal adjustments of the spacing between the die carriers 47 and 48 may be made. However, normal adjustments of the spacing between the die carriers are made by turning a hand-operated nut 140 which is threaded onto the rod 136 externally of the mounting block 82, and which engages the side surface of the mounting block to determine the position of separation between the die carriers when those die carriers are free for movement as a result of the forces of the compression springs 133 and 134.

For effecting some movements of the die carrier 47 along the piston rods 29 and 30, hydraulic rams 141 and 142 are connected to and extend between the die carrier 47 and the crosshead 36 at substantially symmetrical positions on opposite sides of the piston rods 29 and 30, and in symmetrical relationship to the longitudinal symmetrical plane along which the workpiece 127 extends. At its opposite ends, the crosshead 36 has lateral slots 143 and 144 defining tongues 145 and 146 at the ends of the crosshead and extending toward the die carrier, to which tongues the rams 141 and 142 are movably connected by crosspins 147 and 148, respectively. At the other ends of the rams 141 and 142, the respective piston rods 149 and 150 thereof have portions threaded into one end of the slide block 95 and one end of the mounting block 57, whereby the ram axes are on opposite sides of the piston rods 29 and 30 along which the slide carrier 47 moves. Milled recesses 152 and 153 are provided at opposite ends of the slide block 95 and the mounting block 57 at the regions of the connections ofthe piston rods 149 and 150 thereto, in order to afford space for the accommodation of the ends of the cylinders of the rams 141 and 142, thereby affording space for added movement of the die carrier 47 toward the crosshead 36.

In a comparable manner, the die carrier 48 is connected for actuation to the stationary support 22 by hydraulic rams 154 and 155. Piston rods 156 and 157 of the rams 154 and 155, respectively, are threaded into suitable openings for connection to the slide block 95 and the mounting block 57 on opposite sides of the piston rods 29 and 30, and in symmetrical relationship with respect to the longitudinal central plane of the mechanism, along which the workpiece extends. As in the instance of the die carrier 47, the die carrier 48 has milled recesses 152' and 153 for accommodation of the ends of the respective hydraulic cylinders to provide for movements of the die carrier 48 more closely to the stationary support 22. On the stationary support 22, integral tongues 158 and 159 project toward the rams 154 and 155 and are movably connected thereto by cross-pins 160 and 162.

In order to accommodate long workpieces 127 when the workpiece is disposed in the die grooves 125 and 126 of the lower die blocks 64 and 64', and to provide for ease of inserting such long workpieces into the mechanism, the stationary support 22 has an open slot 163 in the mid-region thereof and aligned with the die grooves of the lower die blocks. Likewise, the crosshead 36 has an open slot 164 therein which is also aligned with the die grooves in the lower die blocks. Both of the slots 163 and 164 are of a breadth and depth to provide for the accommodation of workpieces of various sizes in the die grooves of die blocks of an appropriate selected size.

In addition to the support structure for the mechanism and the dies and die carriers, as well as the supports and actuating elements therefor, which have been described, the mechanism further includes clamp structures 165 and 166 which are adapted to grip workpieces at spaced positions on opposite sides of the dies for the transmission of operational forces thereto. As in the instance of the die carriers, the clamp structures 165 and 166 are generally similar, although reversed for operation in opposed relationship, wherefor a description of one is considered to be sufficient and applicable to both. In this instance, the description will apply to the clamp structure 165, which appears at the left-hand side of FIGS. 1, 2, 5 and 6, and corresponding parts of the clamp structure 166 will be designated by like reference numerals having prime mark applied thereto.

A clamp block 167 is secured to the surface of the crosshead 36 on the side thereof facing the die carrier 47 and opposite the bearing blocks 23 and 24, by fastening means, such as bolts 168. This clamp block 167 has a V-shaped recess 169 in the outer surface thereof which faces away from the base plate 20, and which V- shaped recess is symmetrical with the longitudinal central plane defined by the top surfaces of the lower die blocks 64 and 64, as well as the center axis of the workpiece 127 when disposed in the die grooves of the lower die blocks. In addition, the V-shaped recess 169 has its wider end opening toward the die carrier 47 and becomes narrow at the end adjacent the crosshead 36. Opposite side walls 170 and 172 of the V-shaped recess are equi-angularly and symmetrically disposed with respect to a central plane extending therethrough, and which central plane is operationally disposed to coincide with the central plane of the workpiece which is engaged in the dies of the carriers 47 and 48.

Clamp wedges 173 and 174 are mounted in the V- shaped recess 169 for sliding movements along the walls 170 and 172 thereof between extended positions, as shown in FIGS. 1 and 2, and retracted or clamping positions, as shown in FIG. 5. Compression springs 175 and 176 are mounted in longitudinally spaced bores 177 and 178 in the clamp wedge 173 and aligned bores 179 and 180 in the clamp wedge 174; said bores being disposed to the rear of the vertical mid-regions of the clamp wedges 173 and 174, so as to avoid interference with the placement of a workpiece in the mechanism. Furthermore, and as depicted in FIG. 6, longitudinal alignment of the clamp wedges 173 and 174 is maintained by a slide element 182 which is secured to an adjacent side surface of the spacer block 47 by means such as a welded seam 183. The slide element 182 has a projecting tongue 184 which fits slidably in aligned cross-recesses 185 in the clamp wedges. As may be observed, the slide element 182 in addition to maintaining alignment of the clamp wedges in operation, also ensures movement of the clamp wedges into and from the V-shaped recess, which movements, in turn, produce corresponding movements of the clamp wedges toward one another in the recess for effecting clamping action and the release thereof relative to the workpiece disposed therebetween. Further, to retain the clamp wedges 173 and 174 in the V-shaped recess of the clamp block 167 for sliding movement, retaining plates 186 and 187 are secured to the slide block surface by fastening means such as, screws 188 and 189, at posiitons to overlie substantial portions of the side walls of the recess, thereby to overlap outer side portions of the wedges.

In the disclosed structure, and as shown in FIGS. 6 and 8, the clamp wedges 173 and 174 have serrated gripping surfaces, such as 190, for engaging and gripping the workpiece. To provide for replacement and, if desired, for changing the serrations for different sizes and shapes of workpieces, the serrated gripping surfaces are provided on gripping plates 192 and 193 of dovetail section, and which fit into complementary dovetail grooves 194 and 195, respectively, in opposed parallel surfaces 196 and 197 of the clamp wedges. In addition to being of dovetail section, in order to retain the gripping plates on the surfaces in their respective grooves, the plates are also laterally tapered from end to end, so that they can be slid into their respective recesses and removed therefrom by relative longitudinal movement between the plates and their respective gripping wedges. The longitudinal taper, of course, is such that the gripping plates are urged tightly into their respective recesses by the forces applied therethrough in use. The gripping plates are also hardened to withstand the wear and forces encountered in use. There is no substantial marring nor significant affect on the internal strength characteristics of the portions of the workpiece gripped because the gripping plates retained by the clamp wedges are of such an axial length that, in conjunction with the'coefficient of friction present, this axial area gripped permits transmission of sufficient axial thrust to accomplish the necessary upsetting operation without severe squeezing or marring of the workpiece surfaces.

Bearings 198 and 199 are secured to opposite sides of the clamp block 167 by bearing retainers 200 and 202, as shown in FIG. 1, to provide additional support for the crosshead 36 and clamp structure 165 relative to the piston rods 29 and 30.

In the operation of the disclosed mechanism, the initial and normal positions of the parts are as illustrated in FIG. 1. As thus positioned, the hydraulic rams 88 and 88 are retracted to effect separation of the die blocks 64 and 117 of the die carrier 47 and the die blocks 64 and 117' of the die carrier 48. The separation is sufficient to provide for ease of placement of a workpiece between the die blocks and in the respective die grooves.

The hydraulic rams 25 and 26, which actuate the piston rods 29 and 30, are fully extended, as are also the hydraulic rams I41, 142, 154 and 155. The extensions of these hydraulic rams move the crosshead 36 to a position near the bearing blocks 23 and 24, while the die carriers 47 and 48 are moved to positions spaced away from the crosshead 36 and the stationary support 22, respectively, thus effecting withdrawal of the clamp wedges from the recesses in their respective clamp blocks. Such withdrawals of the clamp wedges from the clamp blocks effect a separation of the clamping surfaces of the clamp wedges as a result of the biasing action of the compression springs which extend therebetween, whereupon the clamp structures 165 and 166 are opened for the placement of a workpiece therebetween when the workpiece is placed in the grooves of the lower die blocks. From the outer ends of the clamp structures, the workpiece extends through the slots 164 and 163 in the crosshead in the stationary support, respectively.

For workpieces of a selected size and shape, the die blocks are selected to correspond. However, with the clamping structures disclosed, pairs of clamp wedges are suitable for use with a variety of workpiece diameters. After the workpiece size and shape has been determined and the die blocks and clamp wedges selected for use therewith, it is also necessary to determine the proper normal spacing between the adjacent ends of the opposed die blocks by the adjustment of the spacing between the die carriers 47 and 48. This is accomplished by the adjustable stop 135. It has beenfound that for metal, such as aluminum and aluminum alloys which typically are utilized in conductor wires and rods, excellent results are obtained, both in respect to conductivity and strength, when the normal open spacing between the ends of opposed die blocks is approximately two times the diameter of a workpiece of circular section, but in any event selectively adjusted to be slightly greater than the axial length of all the heat and strength-affected metal adjacent the heat fused joint. The length of this axially extending zone is dependent upon many variables inherent to the joining operation, such as length of time of heat application, amount of compressive force applied, and the intensity of the heat.

Results of actual tests made on various commercial butt-welders available and/or other type joining devices utilized, must be checked to accurately determine the exact initial die block spacing. The usual initial spacing has been found to be generally between two and four times the largest cross-sectional dimension of the work piece. The initial spacing of slightly greater than the axial length of the heat-affected zone insures that the same will be completely removed after the dies are brought together, thereby resulting in a finished joint of only joined parent material. Furthermore, this initial spacing can be further adjusted to match the temper of the finished joint to that of the parent workpiece or to achieve a tensile strength at the joint greater than in the parent metal. This is again determined by known procedures such as examining workpiece metal microstructures to determine what initial spacing is necessary to reproduce a given temper in the parent metal or to obtain additional tensile strength at the joint as desired. The positions of the nuts 138 and 139, which determine the initial position of the die carrier 48 and the position of the hand-operated nut 140, are selected so that with the proper spacing between the adjacent and opposed ends of the die blocks the space therebetween is also substantially centrally located between the clamp structures 165 and 166. In reference to this spacing, the ends of workpieces which are to be joined, or the centerline of a conventional butt weld between the ends of adjoined workpieces are centrally disposed in the space between the opposed ends of the die blocks, asshown in FIGS. 1 and 2.

In most instances, and for most of the metals, such as aluminum, aluminum alloys and copper, utilized for electrical conductors, it is preferable, or necessary, be-

cause of oxidation, to provide an initial, or conventional, heat fusing butt weld between workpiece ends, as shown in FIG. 9, prior to the use of the mechanism disclosed in this application. Such conventional butt welds leave a bulge or flash 203 which encompasses the workpiece. Furthermore, conventional butt welds result in a substantial reduction of strength characteristic on both sides of the workpiece weld joint because-of the application of heat and pressure adjacent the joint. The workpiece metal included within this axial heataffected zone is never completely removed by known prior art upsetters, eventhough the heat-affected metal of the radially projecting weld bulge be removed by hand or automatic shearing operations. In addition to the fact that such a conventional weld does not afford the conductivity, strength and hardness characteristics which are required in wire or rod joints, the bulge or flash protuberance would make the joint unsuitable for further operations, such as continued drawing, coating with insulation, twisting into multiconductor cables, and such further operations Thus, even if the bulge or flash protuberance could be readily removed, the result would be unsatisfactory. Furthermore, if the conventionally welded joint is work-hardened, and the workhardening operation leaves a bulge or protuberance which must be removed by filing or a hand-operation by a skilled operator, the hand-operation requires more time than the work-hardening operation and becomes both expensive and very objectionable.

As shown in FIGS. 4 and 13, each of the die blocks, such as 64 and 117 of a coacting pair, has a V-shaped semicircular recess 204 in the end surface thereof. In each instance, an inner surface 205 of the recess adjoins the die groove at the inner end of the groove to provide a sharp knife edge 206 which, when the coacting die blocks of a pair are brought together, encompasses the workpiece at the end of the die. The die blocks 64 and 117 of each coacting pair also have end surfaces 207 outwardly of the recess 204 and of sub stantial thickness, which end surfaces are milled to serve as stops to prevent damage to the knife edges 206 of the dies, when such dies, in opposed relationship, are brought together in the operation of the mechanism. Also, the depths and sizes of the recesses 204 are sufficient to provide space for the accommodation of metal trimmed from the workpiece during the operation of the mechanism.

FIGS. 11 to 18 inclusive, of the drawings, illustrate sequential steps of the operation of the mechanism, with particular reference to the operations performed on a workpiece. As shown in FIG. 11, cut ends of separate pieces of wire or rod of the same size and material are designated as 127a and 1271;. Such ends are brought together, and in some instances may be susceptible to cold welding, but are usually butt welded by a conventional butt welder, as depicted in FIG. 12. The reason cold welding is unsatisfactory with some metals, such as aluminum, is the rapidity with which oxides are formed on freshly cut and cleaned abutting workpiece end surfaces. In such instances, an oxide interface develops and remains at the joint regardless of the fact that the workpiece ends are immediately cold joined after preparation. The workpiece, in the form shown in FIG. 12, is placed between the die blocks 64 and 117 and the die blocks 64 and 117', with the bulge or flash 203 centered between the ends ofthe opened, separated and initially spaced die blocks. In this position, the workpiece normally rests in'the die grooves 125 and 125 of the lower die blocks, as shown in FIGS. 1 and I3. Thereafter, one set of die blocks, such as 64' and 117. is closed by operation of the hydraulic ram 88', as shown in FIG. 14. Then, the other die blocks, 64 and 117 on the die carrier 47, are brought together or closed by operation of the hydraulic ram 88, thereby to encompass and retain the shape and size of substantial lengthwise portions of the workpiece 127 on opposite sides of an axial length of the workpiece which is slightly longer than the heat-affected zone adjacent the weld and wherein the initial weld is centered, as shown in FIG. 15.

After closing the dies on the respective die carriers 47 and 48, the hydraulic cylinders 154 and are actuated to retract, thereby to close the clamp wedges 173 and 174 against the workpiece at a position adjacent and outward of the die blocks 64 and 117. It may be observed, in reference to FIG. 1, that the retraction of the rams 154 and 155 to close the clamp structure 166, not only moves the die carrier 48 toward the stationary support 22 on the piston rods 29 and 30, but also effects movement of the die carrier 47 by the same amount in the same direction by virtue of the connection between the die carriers afforded by the adjustable stop 135. Then, in addition and by virtue of the connection between the die carrier 47 and the crosshead 36 through the hydraulic rams 141 and 142, the crosshead 36 is also moved toward the stationary support 22 on the piston rods 29 and 30 to maintain the normal open spacing between the clamp wedges 173 and 174.

The clamp wedges 173 and 174 are brought to clamping engagement with opposed surfaces of the workpiece by the retraction of rams 141 and 142, which retraction brings the crosshead 36 closer to the die carrier 47 as the clamp wedges are moved into the V-shaped recess 169 of the clamp structure 165. At this point in the operation, the dies and clamp wedges are in substantially the relative positions depicted in FIG. 16. It is to be noted that the forces of the hydraulic rams 154, 155, and 141 and 142, which are utilized for actuation of the clamp wedges, are controlled to provide ample gripping force against opposed flat longitudinal areas-of the workpieces without materially marring or deforming the engaged segments of the workpieces. It is also to be observed that the clamp wedges are of substantial length, to further distribute the clamping forces over the workpiece without marring or deforming the workpiece materially.

Following the closing of the dies and the gripping of the workpiece on opposite sides of the heat-affected zone, as shown in FIG. 16, the hydraulic cylinders 25 and 26 are retracted to draw the crosshead 36 toward the stationary support 22, thereby bringing the die carriers 47 and 48 and their respective dies together to upset all of the heat effected metal of the workpiece between the opposed die ends, effecting a workhardening outward flow of said heat-effected workpiece metal therebetween, as well as trimming the same back to the normal size of the workpiece by the cutting action of the knife edges 206 and 206', as the dies are closed to the position shown in FIG. 17. The angular inner surfaces 205 of the recesses 204 also effect an outward movement of the trimmed workpiece metal relative to the adjoined portions of the workpiece, so that the trimmed excess flashing metal is broken into pieces and falls away from the workpiece when the dies are separated.

After the operation on the workpiece is thus completed, the clamp wedges are released by operation of the rams 141 and 142, and then the rams 154 and 155, to release their gripping actions on the workpiece. The dies are then sequentially opened by operations of the rams 88 and 88. The rams 25 and 26 are then extended to effect separation of the die carriers 47 and 48, whereupon the dies and the finished workpiece are in substantially the positions illustrated in FIG. 18. This completes one cycle of operation on the mechanism,

after which the finished workpiece is removed and another may be placed therein.

From the foregoing description and references to the accompanying drawings, it may be understood that the method and mechanism of this invention are adapted to the production of joints in metal wire and rods which are work-hardened and finished to have mechanical and electrical characteristics comparable to those of the parent metal. Without the aid of time-consuming and expensive hand operations, which require a skilled craftsman, joints are produced in workpieces, such as wires and rods, which permit further drawing operations to be performed on the wire or rod, or which will pass through a machine that puts an insulating coating on the wire without affecting the operation of that machine, or, where wires thus joined may be twisted into cables. It has been found by tests, that the conductivity through a joint produced as herein set forth, is comparable to that of a continuous strand of'the parent wire. Also, tests have indicated that the wire is as resistant to various mechanical strength tests as the parent wire. In some instances it is even stronger. Moreover, where desired, a parent metal temper condition may be reproduced at and adjacent the finished joint. Since the dies not only straighten and retain linear formation of the workpiece wire or rod for substantial distances on both sides of the joint, and trim the workpiece metal at the joint to the precise normal size of the workpiece, the finished joint in the workpiece is substantially undetectable after its completion, as all previously heateffected or annealed workpiece metal is removed leaving only compressively joined parent metal at the joint. Furthermore, the relatively long gripping surfaces through which forces are applied to the workpieces and their areas of contact of the gripping elements with the workpiece are such as to effect the application of the required forces to the workpiece without undue radial compression or material marring of the workpiece surfaces.

I claim:

1. Apparatus for restoring the original cross-sectional configuration and parent metal properties to the heat fused junction of elongated metal workpieces, the for mation of which junction inherently produces an axially extending zone of heat-affected metal adjacent said junction comprising:

a pair of coacting' dies having coaxial elongated workpiece receptive openings conforming to the external configuration of the parent workpieces;

means for mounting said dies closely about said workpieces to straighten and non-grippingly confine substantial axial segments thereof, located on opposite sides of said junction, within said openings;

adjusting means operable for selectively spacing said dies along said workpieces so that the opposing die ends are in predetermined spaced relation defined by the axial extent of the zone of heat affected metal;

gripper means operable to radially grip said workends while sustaining said workpieces in joined relationship; and e means for trimming and removing the radially upset metal in response to axial movement of said dies thereby to form a finished junction of original external workpiece configuration and to interface parent metal thereat.

2. The invention of claim 1 wherein said trimming and removing means are provided about the peripheral edges of said openings at the said opposed ends of said dies for-shearing said upset metal and removing the same upon contact of said opposed ends.

3. The invention of claim 1, wherein each of said dies is composed of plural parts, at least one of said parts of each die being movable relative to another to allow placement of a workpiece in said opening therein and upon closing of the die to provide complete encompassment and straightening of a said substantial axial segment thereof.

4. The invention of claim 3, wherein said plural parts of each die are guided for relative linear movements toward and from one another by means extending between said parts thereof.

5. The invention of claim 1, wherein each of said dies, when advanced toward one another, is axially guided by means which extend between the dies thereby to assure production of the original crosssection shape of the workpiece.

6. The invention of claim 1, wherein stop means are provided on said opposing die ends for limiting the movements of the dies toward one another thereby to prevent damage to said dies after said upsetting and removal therebetween.

7. The invention of claim 1, wherein said means for moving said gripper means and dies coaxially comprises a pair of workpiece gripping clamps which are spaced axially outward of the dies and which clamps coactingly operate with the dies to effect upset and removal of said heat affected metal, and further wherein each of said clamps and its corresponding die are slidingly connected but independently operable for engaging and disengaging the workpiece.

8. The invention of claim 7, and wherein each workpiece gripping clamp of said pair comprises a pair of workpiece gripping elements which have substantially parallel, opposing workpiece gripping surfaces and 0ppositely disposed outer surfaces which taper outwardly in one direction relative to the gripping surfaces, said gripping elements being mounted for linear sliding movements into and from a longitudinally disposed, V- shaped slot in a guide block and which slot is defined by surfaces which extend longitudinally in acute angular relationship relative to a central plane therebetween whereby each of said slot surfaces engages the outer surface of its respective gripping elements to move the same toward the opposing gripping element as said gripping elements are moved along the slot.

9. The invention of claim 1, wherein the initial die spacing selected by said means for selectively spacing the opposing ends thereof is determined by the metallurgical character of the heat fused workpiece junction and said zone resulting from the temperature, pressure, and time involved in effecting said junction.

10. In apparatus for upsetting and removing the heataffected metal from a heat fused juncture of two coaxially aligned elongated workpieces of like metal, crosssectional size and shape held in a pair of axially spaced upsetting dies, an axial thrust producing workpiece and die actuating gripping mechanism, comprising:

gripping elements mounted in oppposed relationship to one another for linear movement parallel to and toward and from a median plane therebetween axially outwardly of each of the upsetting dies, said gripping elements having elongated gripping surfaces substantially equally spaced from said median plane and substantially parallel thereto, to effect gripping a substantially axial segment of the workpiece therebetween;

a block movable linearly in a direction parallel to said median plane, 7

said block having therein a recess which has slide surfaces converging in equi-angular relationship with respect to opposite sides of said medianplane;

said gripping elements also having outer slide surfaces equi-angularly related to their respective gripping surfaces and engaging said slide surfaces of the block recess to effect said linear movement of the gripping elements towards one another when the block is moved along said median plane in one direction;

means for effecting separation of the gripping elements when the block is moved along the median plane in the opposite direction;

means for effecting movements of said block along the median plane in opposite directions,

said last named means further effecting axial thrust and movement to said workpiece, gripping elements and an adjacent one of the dies when said block is moved along said median plane in said one direction a distance greater than that distance necessary to close said gripping elements on said workpiece; and

means for maintaining the gripping elements in lateral alignment relative to one another during movements of the block and gripping elements.

11. The invention of claim 10, wherein said gripping surfaces of said gripping elements are of sufficient axial length that an appropriate axial thrust on said workpiece can be effected without resulting in any significant surface damage or change in internal strength characteristics of said workpiece.

12. The invention of claim 10, wherein the gripping surface of each of said gripping elements comprises a readily removable and replaceable workpiece gripping late. p 13. The invention of claim 10, wherein the workpiece gripping mechanism is power actuated by controlled hydraulic means.

14. The invention of claim 10, wherein said means for maintaining the gripping elements in lateral alignment relative to one another during movements of the block and gripping elements comprises aligned grooves in corresponding side surfaces of the gripping elements and extending in directions normal to said median plane, and means providing a stationary cross-rail fit ting into said aligned grooves and relative to which the gripping elements are slidable.

15. A method of upsetting and removing all the heataffected metal at and axially adjacent the heat fused junction of two elongated workpieces of like metal and cross-sectional size and shape, thereby resulting in a finished workpiece formed of joined sections of parent metal, comprising the steps of:

enclosing and coaxially aligning substantial axial segments of said workpieces, at opposite ends of and axially outward of the zone of heataffected metal created during the formation of said heat fused junction, in elongated axially aligned die openings of uniform size and shape corresponding to the normal exterior size and shape of the workpieces;

gripping substantial axial portions of the workpieces axially beyond said dies and enclosed segments;

applying force through the gripped portions to the enclosed segments and to said dies to effect predetermined linear, relative movement of the dies and workpieces coaxially toward one another thereby to radially upset all of the heat-affected metal between the adjacent die ends, while sustaining said workpieces in joined relationship and while the dies maintain the normal size and linearity of the workpieces at said sustained junction;

and trimming the upset workpiece metal at said sustained junction to normal sectional size and shape during movement of the dies toward one another to effect removal of the upset metal and to provide a linearly smooth finished joint at said junction.

16. The method of claim 15, wherein the said relative movement of the dies toward one another is a distance as least as long as the axial length of said zone of heataffected metal.

17. The method of claim 15, wherein the enclosed axial workpiece segments are of a sufficient length to assure maintenance of the normal size, shape and coaxial alignment of the workpieces.

18. The method of claim 15, wherein the gripped axial workpiece portions are of a sufficient length to allow the application of axial force through said gripped portions without causing any significant surface damage thereto or impairing the strength characteristics of said finished workpiece.

19. The method of claim 15, wherein said trimming of the workpiece metal to its normal sectional size and shape is performed by adjacent end edges and surfaces of said dies as said dies move toward engagement with one another.

20. The method of claim 19, further characterized by the step of stopping movement of the dies toward one another by engagement of surfaces thereon other than said adjacent end edges when said trimming has resulted in said linearly smooth finished joint whereby to protect said adjacent end edges of said dies from damage and wear.

21. The method of claim 15, wherein the gripping of the workpieces is effected by radial forces independent of those utilized for effecting enclosure of said substantial axial segments in said die openings.

Claims (21)

1. Apparatus for restoring the original cross-sectional configuration and parent metal properties to the heat fused junction of elongated metal workpieces, the formation of which junction inherently produces an axially extending zone of heataffected metal adjacent said junction comprising: a pair of coacting dies having coaxial elongated workpiece recepTive openings conforming to the external configuration of the parent workpieces; means for mounting said dies closely about said workpieces to straighten and non-grippingly confine substantial axial segments thereof, located on opposite sides of said junction, within said openings; adjusting means operable for selectively spacing said dies along said workpieces so that the opposing die ends are in predetermined spaced relation defined by the axial extent of the zone of heat affected metal; gripper means operable to radially grip said workpieces axially beyond each of said dies; means for simultaneously and coactingly moving said gripper means and dies to thrust said workpieces uninterruptedly toward one another with sufficient force to radially upset all the heat affected metal of said zone and junction between said opposing die ends while sustaining said workpieces in joined relationship; and means for trimming and removing the radially upset metal in response to axial movement of said dies thereby to form a finished junction of original external workpiece configuration and to interface parent metal thereat.

2. The invention of claim 1 wherein said trimming and removing means are provided about the peripheral edges of said openings at the said opposed ends of said dies for shearing said upset metal and removing the same upon contact of said opposed ends.

3. The invention of claim 1, wherein each of said dies is composed of plural parts, at least one of said parts of each die being movable relative to another to allow placement of a workpiece in said opening therein and upon closing of the die to provide complete encompassment and straightening of a said substantial axial segment thereof.

4. The invention of claim 3, wherein said plural parts of each die are guided for relative linear movements toward and from one another by means extending between said parts thereof.

5. The invention of claim 1, wherein each of said dies, when advanced toward one another, is axially guided by means which extend between the dies thereby to assure production of the original cross-section shape of the workpiece.

6. The invention of claim 1, wherein stop means are provided on said opposing die ends for limiting the movements of the dies toward one another thereby to prevent damage to said dies after said upsetting and removal therebetween.

7. The invention of claim 1, wherein said means for moving said gripper means and dies coaxially comprises a pair of workpiece gripping clamps which are spaced axially outward of the dies and which clamps coactingly operate with the dies to effect upset and removal of said heat affected metal, and further wherein each of said clamps and its corresponding die are slidingly connected but independently operable for engaging and disengaging the workpiece.

8. The invention of claim 7, and wherein each workpiece gripping clamp of said pair comprises a pair of workpiece gripping elements which have substantially parallel, opposing workpiece gripping surfaces and oppositely disposed outer surfaces which taper outwardly in one direction relative to the gripping surfaces, said gripping elements being mounted for linear sliding movements into and from a longitudinally disposed, V-shaped slot in a guide block and which slot is defined by surfaces which extend longitudinally in acute angular relationship relative to a central plane therebetween whereby each of said slot surfaces engages the outer surface of its respective gripping elements to move the same toward the opposing gripping element as said gripping elements are moved along the slot.

9. The invention of claim 1, wherein the initial die spacing selected by said means for selectively spacing the opposing ends thereof is determined by the metallurgical character of the heat fused workpiece junction and said zone resulting from the temperature, pressure, and time involved in effecting said junction.

10. In apparatus for upsetting and removing the heat-affected metal from a heat fused juncture of two coaxially aligned elongated workpieces of like metal, cross-sectional size and shape held in a pair of axially spaced upsetting dies, an axial thrust producing workpiece and die actuating gripping mechanism, comprising: gripping elements mounted in oppposed relationship to one another for linear movement parallel to and toward and from a median plane therebetween axially outwardly of each of the upsetting dies, said gripping elements having elongated gripping surfaces substantially equally spaced from said median plane and substantially parallel thereto, to effect gripping a substantially axial segment of the workpiece therebetween; a block movable linearly in a direction parallel to said median plane, said block having therein a recess which has slide surfaces converging in equi-angular relationship with respect to opposite sides of said median-plane; said gripping elements also having outer slide surfaces equi-angularly related to their respective gripping surfaces and engaging said slide surfaces of the block recess to effect said linear movement of the gripping elements towards one another when the block is moved along said median plane in one direction; means for effecting separation of the gripping elements when the block is moved along the median plane in the opposite direction; means for effecting movements of said block along the median plane in opposite directions, said last named means further effecting axial thrust and movement to said workpiece, gripping elements and an adjacent one of the dies when said block is moved along said median plane in said one direction a distance greater than that distance necessary to close said gripping elements on said workpiece; and means for maintaining the gripping elements in lateral alignment relative to one another during movements of the block and gripping elements.

11. The invention of claim 10, wherein said gripping surfaces of said gripping elements are of sufficient axial length that an appropriate axial thrust on said workpiece can be effected without resulting in any significant surface damage or change in internal strength characteristics of said workpiece.

12. The invention of claim 10, wherein the gripping surface of each of said gripping elements comprises a readily removable and replaceable workpiece gripping plate.

13. The invention of claim 10, wherein the workpiece gripping mechanism is power actuated by controlled hydraulic means.

14. The invention of claim 10, wherein said means for maintaining the gripping elements in lateral alignment relative to one another during movements of the block and gripping elements comprises aligned grooves in corresponding side surfaces of the gripping elements and extending in directions normal to said median plane, and means providing a stationary cross-rail fitting into said aligned grooves and relative to which the gripping elements are slidable.

15. A method of upsetting and removing all the heat-affected metal at and axially adjacent the heat fused junction of two elongated workpieces of like metal and cross-sectional size and shape, thereby resulting in a finished workpiece formed of joined sections of parent metal, comprising the steps of: enclosing and coaxially aligning substantial axial segments of said workpieces, at opposite ends of and axially outward of the zone of heataffected metal created during the formation of said heat fused junction, in elongated axially aligned die openings of uniform size and shape corresponding to the normal exterior size and shape of the workpieces; gripping substantial axial portions of the workpieces axially beyond said dies and enclosed segments; applying force through the gripped portions to the enclosed segments and to said dies to effect predetermined linear, relative movement of the dies and workpieces coaxially toward one another thereby to radially upset all of the heat-affected metal betWeen the adjacent die ends, while sustaining said workpieces in joined relationship and while the dies maintain the normal size and linearity of the workpieces at said sustained junction; and trimming the upset workpiece metal at said sustained junction to normal sectional size and shape during movement of the dies toward one another to effect removal of the upset metal and to provide a linearly smooth finished joint at said junction.

16. The method of claim 15, wherein the said relative movement of the dies toward one another is a distance as least as long as the axial length of said zone of heat-affected metal.

17. The method of claim 15, wherein the enclosed axial workpiece segments are of a sufficient length to assure maintenance of the normal size, shape and coaxial alignment of the workpieces.

18. The method of claim 15, wherein the gripped axial workpiece portions are of a sufficient length to allow the application of axial force through said gripped portions without causing any significant surface damage thereto or impairing the strength characteristics of said finished workpiece.

19. The method of claim 15, wherein said trimming of the workpiece metal to its normal sectional size and shape is performed by adjacent end edges and surfaces of said dies as said dies move toward engagement with one another.

20. The method of claim 19, further characterized by the step of stopping movement of the dies toward one another by engagement of surfaces thereon other than said adjacent end edges when said trimming has resulted in said linearly smooth finished joint whereby to protect said adjacent end edges of said dies from damage and wear.

21. The method of claim 15, wherein the gripping of the workpieces is effected by radial forces independent of those utilized for effecting enclosure of said substantial axial segments in said die openings.

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