Twisting device for forged stranded welding wire

Abstract

This invention discloses a stranding device for forged stranded welding wire, belonging to the field of welding technology. It mainly includes a stranding machine, a forging machine, and a second rolling mill. The outer strands are rolled into a trapezoidal shape by the second rolling mill. The trapezoidal shape includes a bottom wall, inclined side walls, a recessed portion, and an obliquely protruding portion. The inclined side walls gradually slope outwards from the bottom wall towards the recessed portion. The recessed portion is closer to the bottom wall than the obliquely protruding portion. When multiple trapezoidal outer strands are stranded onto a central strand by the stranding machine, the bottom wall abuts against the outer periphery of the central strand. Adjacent inclined side walls of two adjacent outer strands abut against each other, forming a wedge-shaped gap. The trapezoidal outer strands and the central strand are stranded together by the stranding machine to form a stranded welding wire. After being drawn from the stranding machine, the stranded welding wire undergoes radial impact on its outer periphery by the forging machine. The stranding device for forged stranded welding wire of this invention can form a cylindrical surface on the stranded welding wire, thereby improving wear on the conductive tip and enhancing the stability of wire feeding and conductivity.

Description

Technical Field

[0001] This invention relates to the field of welding technology, and more specifically to a stranding device for forged stranded welding wire. Background Technology

[0002] Forged stranded welding wire is made of multiple single wires spirally twisted together in a specific structure. As the welding wire is fed in, the welding arc rotates, which stirs the molten pool in real time. This promotes the uniform distribution of arc energy and chemical components, facilitates the escape of gases from the molten pool, and helps slag inclusions float to the surface, greatly improving weld quality. Because of its superior weld quality, multi-stranded welding wire has been widely adopted in specialized fields such as military, aerospace, marine engineering, and pressure equipment.

[0003] Currently, the outer monofilaments of forged stranded welding wire on the market are all circular cross-section structures. After stranding, irregularly shaped grooves and arc protrusions appear on the surface. This not only increases the wear of the contact tip, but also is not conducive to the stability of wire feeding and conductivity.

[0004] Therefore, it is necessary to provide a new stranding device for forged stranded welding wire. Summary of the Invention

[0005] Based on the aforementioned problems in the prior art, the purpose of this invention is to provide a stranding device for forged stranded welding wire, which can form a cylindrical surface on the surface of the stranded welding wire, thereby improving wear on the conductive tip and enhancing the stability of wire feeding and conductivity.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A stranding device for forged stranded welding wire is provided. The stranded welding wire includes a central wire and multiple peripheral wires spirally wound around the central wire. The stranding device for forged stranded welding wire includes a stranding machine, a forging machine, and a second rolling mill. The stranding machine and the forging machine are arranged sequentially. The peripheral wires with circular cross-sections are processed by the second rolling mill before entering the stranding machine, so that the peripheral wires are rolled into a trapezoidal shape by the second rolling mill. The cross-sectional profile of the trapezoidal peripheral wire includes a bottom wall, inclined side walls symmetrically arranged on both sides of the bottom wall, a recessed portion located on the opposite side of the bottom wall, and obliquely protruding portions symmetrically arranged on both sides of the recessed portion. The inclined side walls gradually slope outward from the bottom wall towards the recessed portion. The obliquely protruding portions extend outward along the diagonal of the trapezoidal cross-section and protrude from the surface of the recessed portion. When multiple trapezoidal outer wires are twisted onto the central wire by a stranding machine, the bottom wall abuts against the outer periphery of the central wire. The adjacent inclined sidewalls of two adjacent outer wires abut against each other and form a wedge-shaped gap. The trapezoidal outer wires and the central wire are twisted together by a stranding machine to form a stranded welding wire. After the stranded welding wire is drawn out from the stranding machine, it is subjected to radial impact on the outer periphery of the stranded welding wire by a forging machine. Under the action of radial impact force, the oblique protrusion on the surface of the recessed part undergoes plastic deformation, causing the original oblique protrusion to deform and slide along the radial and tangential directions. This causes the adjacent inclined sidewalls of the adjacent outer wires to move closer to each other until the wedge-shaped gap is compressed, until the adjacent inclined sidewalls of the adjacent outer wires are tightly attached. At the same time, the original oblique protrusion shrinks inward until the oblique protrusion and the recess are located on the same circumferential path, so that the outer side of the original oblique protrusion and the recess is transformed into a cylindrical surface concentric with the central wire.

[0007] Furthermore, the stranding device for forged stranded welding wire also includes a rolling mill one, which is located before the rolling mill two. The rolling mill one rolls the outer wire with a circular cross section into a square shape with a square cross section. The rolling mill one is a Turkish head rolling mill unit.

[0008] Furthermore, the second rolling mill includes a first forming roll and a second forming roll arranged opposite to each other on their peripheral walls. The outer peripheral wall of the first forming roll is provided with forming ribs, and the outer peripheral wall of the second forming roll is provided with forming grooves.

[0009] Furthermore, a forming rib corresponding to the trapezoidal recess is protruding on the peripheral sidewall of the forming roller one at the middle position, and a variable diameter arc surface is symmetrically arranged on the peripheral sidewall of the forming roller one on both sides of the forming rib, the diameter of the variable diameter arc surface gradually decreasing from the inside to the outside.

[0010] Furthermore, the forming groove has variable diameter sidewalls on opposite sides, and the distance between the two variable diameter sidewalls gradually increases radially outward.

[0011] Furthermore, the stranding machine includes a stranding zone, which includes a guide roller assembly and a paralleling die. The trapezoidal outer strands are evenly separated by the guide roller assembly. After passing through the guide roller assembly, the outer strands enter the paralleling die, and when passing through the closing hole of the paralleling die, the outer strands are brought together with the center strand.

[0012] Furthermore, the multiple wire guide roller groups are distributed circumferentially at intervals. Each wire guide roller group includes a guide roller one and a guide roller two arranged opposite to each other. A V-shaped limiting groove one is recessed on the outer peripheral wall of the guide roller one, and a V-shaped limiting groove two is recessed on the outer peripheral wall of the guide roller two. The trapezoidal outer wire passes between the V-shaped limiting groove one and the V-shaped limiting groove two.

[0013] Furthermore, the stranding device for forged stranded welding wire also includes a straightening machine, which is located after the stranding machine and pre-straightens the stranded welding wire drawn out from the stranding machine through multiple interlaced rollers of the straightening machine.

[0014] Furthermore, the stranding device for forging stranded welding wire also includes a traction machine, which is located in the downstream section of the forging machine.

[0015] Furthermore, the stranding device for forged stranded welding wire also includes a take-up machine located after the traction machine, which uses the constant tension of the take-up machine's torque motor to neatly wind the stranded welding wire onto the I-beam reel.

[0016] The beneficial effects of this invention are as follows: The stranding device for forged stranded welding wire provided by this invention includes a stranding machine, a forging machine, and a second rolling mill. The stranding machine and the forging machine are arranged sequentially. The outer wire with a circular cross-section passes through the second rolling mill before entering the stranding machine, so that the outer wire is rolled into a trapezoidal shape by the second rolling mill. The trapezoidal shape includes a bottom wall, inclined side walls symmetrically arranged on both sides of the bottom wall, a recessed portion located on the opposite side of the bottom wall, and obliquely protruding portions symmetrically arranged on both sides of the recessed portion. The inclined side walls gradually slope outward from the bottom wall towards the recessed portion, thereby the two inclined side walls form the waist of the trapezoidal shape. The recessed portion is closer to the bottom wall than the obliquely protruding portion. The obliquely protruding portion extends outward along the diagonal of the cross-section of the trapezoidal shape and protrudes from the surface of the recessed portion. When multiple trapezoidal outer wires are stranded onto the central wire by the stranding machine, the bottom wall abuts against the outer periphery of the central wire, and the adjacent inclined side walls of two adjacent outer wires abut against each other and form a wedge. The wedge-shaped slit has a width that gradually increases radially outward. The trapezoidal outer wire and the center wire are twisted together by a stranding machine to form a stranded welding wire. After being drawn out of the stranding machine, the stranded welding wire is subjected to radial impact on its outer circumference by a forging machine. This causes the obliquely protruding part on the surface of the recessed part to undergo plastic deformation under the action of radial impact force. This causes the original obliquely protruding part to deform and slide radially and tangentially, bringing the adjacent inclined sidewalls of the adjacent outer wires closer together until they are compressed into the wedge-shaped slit. This continues until the adjacent inclined sidewalls of the adjacent outer wires are tightly attached to each other. At the same time, the original obliquely protruding part shrinks inward to be on the same circumferential path as the recessed part, transforming the outer side of the original obliquely protruding part and the recessed part into a cylindrical surface concentric with the center wire. Therefore, compared with the prior art, the stranding device for forging stranded welding wire provided by this invention can construct the surface of the stranded welding wire into a cylindrical shape, thereby significantly improving the wear of the conductive tip and improving the stability of wire feeding and conductivity. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a simplified structural diagram of a stranding device for forged stranded welding wire provided in an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram showing the positional relationship between rolling mill 1 and rolling mill 2 provided in an embodiment of the present invention.

[0020] Figure 3 This is a cross-sectional schematic diagram of a square shape provided in an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the operating state of the second rolling mill provided in an embodiment of the present invention.

[0022] Figure 5 for Figure 4 A cross-sectional view of the EE location.

[0023] Figure 6 This is a cross-sectional schematic diagram of the second rolling mill provided in an embodiment of the present invention.

[0024] Figure 7 This is a three-dimensional structural diagram of the twisting area provided in an embodiment of the present invention.

[0025] Figure 8 A front view of the twisted area provided in an embodiment of the present invention. Figure 1 .

[0026] Figure 9 for Figure 8 A cross-sectional view of the FF position.

[0027] Figure 10 for Figure 9 An enlarged schematic diagram of region A in the middle.

[0028] Figure 11 A front view of the twisted area provided in an embodiment of the present invention. Figure 2 .

[0029] Figure 12 for Figure 11 A cross-sectional diagram of the GG location.

[0030] Figure 13 for Figure 12 The view shows an overlay of the stranded welding wire's shape before and after passing through the forging machine.

[0031] In the figure, the following labels are used: 100, stranded welding wire; 200, cylindrical surface; 10, stranding machine; 11, stranding zone; 111, wire guide roller group; 1111, guide roller one; 1112, guide roller two; 1113, V-shaped limiting groove one; 1114, V-shaped limiting groove two; 112, wire pulling die; 20, straightening machine; 30, forging machine; 40, traction machine; 50, take-up machine; 60, roller. Rolling mill one; 70. Roll mill two; 71. Forming roll one; 711. Variable diameter arc surface; 712. Forming rib; 72. Forming roll two; 721. Forming groove; 722. Variable diameter sidewall; 80. Center wire; 90. Outer wire; 91. Square shape; 92. Trapezoidal shape; 921. Bottom wall; 922. Inclined sidewall; 923. Recessed part; 924. Sloping part; 925. Wedge-shaped gap. Detailed Implementation

[0032] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0033] It should be noted that when a component is referred to as "connected to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0036] Throughout this specification, reference to "an embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this application. Therefore, the phrases "in one embodiment," "in some embodiments," or "in some of these embodiments" appear in various places throughout the specification, and not all refer to the same embodiment. Furthermore, in one or more embodiments, a particular feature, structure, or characteristic may be combined in any suitable manner.

[0037] Please refer to Figures 1 to 13 As shown, the stranding device for forged stranded welding wire provided by the present invention will now be described. This stranding device is used to strand a stranded welding wire 100, which includes a central wire 80 and a plurality of peripheral wires 90 arranged circumferentially along the central wire 80 and wound helically around the outer periphery of the central wire 80. Figure 12 The image uses dashed arrows to illustrate the stress analysis of the outer wire 90 as it passes through the forging machine 30. Figure 13The structure of the stranded welding wire 100 after forging is shown in dashed lines. The stranding device for forging stranded welding wire includes a stranding machine 10, a forging machine 30, and a rolling mill 70. The stranding machine 10 and the forging machine 30 are arranged sequentially. The outer wire 90 with a circular cross-section is processed by the rolling mill 70 before entering the stranding machine 10. Figure 5 As shown, the outer wire 90 is rolled into a trapezoidal shape 92 by the rolling mill 70, as... Figure 12 As shown, the outer wire 90 of the trapezoidal shape 92 has a cross-sectional profile including a bottom wall 921, inclined side walls 922 symmetrically arranged on both sides of the bottom wall 921, a recess 923 located on the opposite side of the bottom wall 921, and obliquely protruding portions 924 symmetrically arranged on both sides of the recess 923. The inclined side walls 922 gradually slope outward from the bottom wall 921 towards the recess 923, thereby the two inclined side walls 922 forming the waist of the trapezoidal shape 92. The obliquely protruding portions 924 extend outward along the diagonal of the cross-section of the trapezoidal shape 92 and protrude from the surface of the recess 923. The outer wires 90 of the multiple trapezoidal shapes 92 pass through... When the stranding machine 10 strands the wire onto the center wire 80, the bottom wall 921 abuts against the outer periphery of the center wire 80. The adjacent inclined sidewalls 922 of two adjacent outer wires 90 abut against each other, forming a wedge-shaped gap 925. The width of the wedge-shaped gap 925 gradually increases radially outward. The trapezoidal outer wires 90 and the center wire 80 are stranded together by the stranding machine 10 to form a stranded welding wire 100. After being drawn out from the stranding machine 10, the stranded welding wire 100 undergoes radial impact on its outer periphery by the forging machine 30. This causes the obliquely protruding portion 924 on the surface of the protruding recess 923 to undergo plastic deformation under the radial impact force. Figure 13 As shown, the original inclined portion 924 is deformed and tangentially slid, causing the adjacent inclined sidewalls 922 of the adjacent outer wires 90 to move closer to each other until they are compressed into the wedge-shaped gap 925, until the adjacent inclined sidewalls 922 of the adjacent outer wires 90 are tightly attached. At the same time, the original inclined portion 924 is retracted until the inclined portion 924 and the recessed portion 923 are located on the same circumferential path, so that the outer side of the original inclined portion 924 and the recessed portion 923 is transformed into a cylindrical surface 200 concentric with the central wire 80. Therefore, compared with the prior art, the stranding device for forged stranded welding wire provided in this embodiment of the invention can construct the surface of the stranded welding wire 100 into a cylindrical shape, thereby significantly improving the wear of the conductive tip and improving the stability of wire feeding and conductivity.

[0038] It is understandable that when the forging machine 30 applies radial impact to the outer periphery of the stranded welding wire 100, the bottom wall 921 will be compressed and deformed to fit tightly against the outer periphery of the center wire 80, so that the outer wire 90 and the center wire 80 are interlocked, thereby improving the anti-loosening ability of the stranded welding wire 100 and making it less likely to fall apart during the wire feeding process when the stranded welding wire 100 is used for welding.

[0039] like Figure 2 , Figure 3 As shown, in some embodiments, the stranding device for forged stranded welding wire further includes a rolling mill 60, which is located before the rolling mill 70. The rolling mill 60 rolls the outer wire 90 with a circular cross-section into a square shape 91 with a square cross-section, thereby achieving multi-stage rolling of the outer wire 90 to avoid die breakage and wire breakage. Specifically, in this embodiment, the rolling mill 60 is a Turkish head rolling mill unit.

[0040] like Figure 4 , Figure 5 and Figure 6 As shown, in some embodiments, the rolling mill 70 includes a forming roll 71 and a forming roll 72 with their peripheral sidewalls arranged opposite each other. The outer peripheral wall of the forming roll 71 is provided with forming ribs 712, and the outer peripheral wall of the forming roll 72 is provided with forming grooves 721. When the outer wire 90 of the square shape 91 passes between the forming roll 71 and the forming roll 72, the position of the outer wire 90 is fixed by the forming grooves 721. The side of the outer wire 90 of the square shape 91 that is close to the forming rib 712 is deformed by the forming rib 712 to form a trapezoidal shape 92 recess 923. The outer wire 90 is located on one side of the bottom wall of the forming groove 721 and is formed by limiting and pressing to form the bottom wall 921. The opposite side walls of the forming groove 721 limit and press the outer wire 90 of the square shape 91, causing the outer wire 90 to be deformed by the opposite side walls of the forming groove 721 to form the inclined side wall 922.

[0041] like Figure 5 , Figure 6 As shown, in some embodiments, a forming rib 712 corresponding to the recess 923 of the trapezoidal shape 92 is provided on the peripheral sidewall of the forming roller 71 at the middle position, so that the forming rib 712 is plastically squeezed to form the shape of the recess 923 of the trapezoidal shape 92 when the outer wire 90 is rolled. In addition, a variable diameter arc surface 711 is symmetrically provided on the peripheral sidewall of the forming roller 71 on both sides of the forming rib 712. The diameter of the variable diameter arc surface 711 gradually decreases from the inside to the outside, so that the variable diameter arc surface 711 adapts to the extrusion of the oblique part 924.

[0042] like Figure 5 , Figure 6 As shown, in some embodiments, the forming groove 721 has variable diameter sidewalls 722 on opposite sides, and the distance between the two variable diameter sidewalls 722 gradually increases radially outward, so that the opposite sidewalls of the forming groove 721 form a shape corresponding to the inclined sidewall 922 of the trapezoidal shape 92, so that when the outer wire 90 and the forming groove 721 are squeezed against each other, the opposite sidewalls of the outer wire 90 are forced to deform to form the inclined sidewall 922 of the trapezoidal shape 92.

[0043] like Figure 1, Figure 8 and Figure 9 As shown, in some embodiments, the stranding machine 10 includes a stranding area 11, which includes a guide roller assembly 111 and a paralleling die 112. The outer wires 90 of the trapezoidal shape 92 are evenly separated by the guide roller assembly 111, so that the outer wires 90 of the trapezoidal shape 92 can be evenly distributed around the center wire 80 in the circumferential direction. After passing through the guide roller assembly 111, the outer wires 90 enter the paralleling die 112. When passing through the closing hole of the paralleling die 112, the outer wires 90 and the center wire 80 are closed to form the round shape of the stranded welding wire 100. At the same time, the outer wires 90 are spirally wound around the center wire 80 as the stranding machine 10 rotates. Specifically, in this embodiment, the guide roller assembly 111 follows the stranding machine 10 to make a circular rotation, driving the outer wires 90 to revolve around the center wire 80.

[0044] In some embodiments, the stranding machine 10 may be, but is not limited to, a tubular stranding machine, a frame stranding machine, etc.

[0045] like Figure 9 , Figure 10 As shown, in some embodiments, multiple guide roller groups 111 are distributed circumferentially at intervals. Each guide roller group 111 includes a guide roller 1111 and a guide roller 1112 arranged opposite to each other. A V-shaped limiting groove 1113 is recessed on the outer peripheral wall of the guide roller 1111, and a V-shaped limiting groove 1114 is recessed on the outer peripheral wall of the guide roller 1112. The outer wire 90 of the trapezoidal shape 92 passes between the V-shaped limiting groove 1113 and the V-shaped limiting groove 1114. Specifically, the guide roller 1111 and the guide roller 1112 are distributed along the diagonal of the trapezoidal shape 92 to guide the outer wire 90 while preventing torsion.

[0046] like Figure 1 As shown, in some embodiments, the stranding device for forged stranded welding wire further includes a straightener 20, which is located after the stranding machine 10. The straightener 20 pre-straightens the stranded welding wire 100 drawn out from the stranding machine 10 through a plurality of interlaced rollers.

[0047] like Figure 1 As shown, in some embodiments, the stranding device for forged stranded welding wire further includes a traction machine 40, which is located after the forging machine 30 and drags the stranded welding wire 100.

[0048] like Figure 1 As shown, in some embodiments, the stranding device for forged stranded welding wire also includes a take-up machine 50 located after the traction machine 40, which uses the constant tension of the torque motor of the take-up machine 50 to neatly wind the stranded welding wire 100 onto the I-beam reel.

[0049] In some embodiments, the forging machine 30 is a rotary forging machine. The modules of the rotary forging machine are placed in pairs facing each other and apply radial force rapidly and successively. Using the high-frequency radial impact of multiple hammers, the gaps between the strands of the welding wire 100 are compacted, the outer diameter is reduced and the roundness is improved, and the wires are interlocked with each other. In particular, the bottom wall 921 is tightly attached to the outer peripheral wall of the center wire 80, and the adjacent inclined sidewalls 922 of the adjacent outer wires 90 are brought closer to each other until the wedge-shaped gap 925 is compressed until the adjacent inclined sidewalls 922 of the adjacent outer wires 90 are tightly attached. At the same time, the original inclined protrusion 924 is retracted to be located on the same circumferential path as the recessed portion 923, so that the outer side of the original inclined protrusion 924 and the recessed portion 923 are transformed into a cylindrical surface 200 concentric with the center wire 80. At the same time, the spiral structure formed by the twisting of the outer wires 90 is retained, and the characteristics of the rotating arc are retained.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A stranding device for forged stranded welding wire, the stranded welding wire comprising a central wire and a plurality of peripheral wires wound around the central wire, characterized in that: The stranding device for forged stranded welding wire includes a stranding machine, a forging machine, and a second rolling mill. The stranding machine and the forging machine are arranged sequentially. The outer wire with a circular cross-section is processed by the second rolling mill before entering the stranding machine, so that the outer wire is rolled into a trapezoidal shape by the second rolling mill. The cross-sectional profile of the trapezoidal outer wire includes a bottom wall, inclined side walls symmetrically arranged on both sides of the bottom wall, a recessed portion located on the opposite side of the bottom wall, and obliquely protruding portions symmetrically arranged on both sides of the recessed portion. The inclined side walls gradually slope outward from the bottom wall towards the recessed portion. The obliquely protruding portions extend outward along the diagonal of the cross-section of the trapezoidal shape and protrude from the surface of the recessed portion. When multiple trapezoidal outer wires are stranded onto the central wire by the stranding machine, the bottom wall abuts against the central wire. The outer periphery of the core wire, the adjacent inclined sidewalls of two adjacent outer wires abut and form a wedge-shaped gap. The trapezoidal outer wires and the core wire are twisted together by a stranding machine to form a stranded welding wire. After the stranded welding wire is drawn out from the stranding machine, it is subjected to radial impact by a forging machine. Under the action of radial impact force, the oblique protrusion on the surface of the recessed part undergoes plastic deformation, causing the original oblique protrusion to deform and slide along the radial and tangential directions. This causes the adjacent inclined sidewalls of the adjacent outer wires to move closer to each other until the wedge-shaped gap is compressed, until the adjacent inclined sidewalls of the adjacent outer wires are tightly attached. At the same time, the original oblique protrusion shrinks inward until the oblique protrusion and the recess are on the same circumferential path, so that the outer side of the original oblique protrusion and the recess is transformed into a cylindrical surface concentric with the core wire.

2. The stranding device for forged stranded welding wire according to claim 1, characterized in that: The stranding device for forged stranded welding wire also includes a rolling mill one, which is located in front of the rolling mill two. The rolling mill one rolls the outer wire with a circular cross section into a square shape with a square cross section. The rolling mill one is a Turkish head rolling mill unit.

3. The stranding device for forged stranded welding wire according to claim 1, characterized in that: The second rolling mill includes a first forming roll and a second forming roll arranged opposite to each other on their peripheral walls. The outer peripheral wall of the first forming roll is provided with forming ribs, and the outer peripheral wall of the second forming roll is provided with forming grooves.

4. The stranding device for forged stranded welding wire according to claim 3, characterized in that: The forming roller has a forming rib protruding from its peripheral sidewall and at the middle position, corresponding to the trapezoidal recess. The forming roller has variable diameter arc surfaces symmetrically arranged on both sides of the forming rib on its peripheral sidewall, with the diameter of the variable diameter arc surfaces gradually decreasing from the inside to the outside.

5. The stranding device for forged stranded welding wire according to claim 3, characterized in that: The forming groove has variable diameter sidewalls on opposite sides, and the distance between the two variable diameter sidewalls gradually increases radially outward.

6. The stranding device for forged stranded welding wire according to claim 1, characterized in that: The stranding machine includes a stranding zone, which includes a guide roller assembly and a paralleling die. The trapezoidal outer strands are evenly separated by the guide roller assembly. After passing through the guide roller assembly, the outer strands enter the paralleling die, and when passing through the closing hole of the paralleling die, the outer strands are brought together with the center strand.

7. The stranding device for forged stranded welding wire according to claim 6, characterized in that: Multiple wire guide roller groups are distributed circumferentially. Each wire guide roller group includes a guide roller 1 and a guide roller 2 arranged opposite to each other. A V-shaped limiting groove 1 is recessed on the outer peripheral wall of the guide roller 1, and a V-shaped limiting groove 2 is recessed on the outer peripheral wall of the guide roller 2. The trapezoidal outer wire passes between the V-shaped limiting groove 1 and the V-shaped limiting groove 2.

8. The stranding device for forged stranded welding wire according to any one of claims 1-7, characterized in that: The stranding device for forged stranded welding wire also includes a straightening machine, which is located after the stranding machine and pre-straightens the stranded welding wire drawn out from the stranding machine through multiple staggered rollers of the straightening machine.

9. The stranding device for forged stranded welding wire according to any one of claims 1-7, characterized in that: The stranding device for forged stranded welding wire also includes a traction machine, which is located in the rear of the forging machine.

10. The stranding device for forged stranded welding wire according to claim 9, characterized in that: The stranding device for forged stranded welding wire also includes a take-up machine located after the traction machine, which uses the constant tension of the take-up machine's torque motor to neatly wind the stranded welding wire onto the I-beam reel.

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