JPH03291193A - Welding wire and production thereof - Google Patents

Abstract

PURPOSE:To allow the smooth sliding energization by the contact tip of a welding torch by welding plural wires in a longitudinal direction and specifying the average diameter of the wires exclusive of a weld zone, the diameter of the weld zone and the length of the weld zone to a specific relation. CONSTITUTION:The welding wire is formed by welding at least two pieces of the wires 1, 1. The average diameter d1 of the wire 11 exclusive of the weld zone 12, the average diameter d2 of the weld zone 12 and the length l of the weld zone 12 are determined to the relation satisfying equation I and equation II. Two pieces of the wires 1, 1 are inserted into an insulating pipe 4 and the front end faces thereof are joined and welded by passing a current thereto. A flux 6 is filled in the pipe 4 at the time of welding and thereafter the wires are welded. The connection without generating the misalignment of the central axis is easily executed in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to welded wire rods such as steel wires and iron wires, and methods for manufacturing the same.

[Prior Art] Welding of wire rods such as steel wires and iron wires is performed in various fields such as machinery, electricity, automobile industry, and spring manufacturing industry.

A conventional method for welding wire rods will be explained using drawings.

FIGS. 2(a) to 2(d) show a conventional wire rod welding method. In FIG. 2(a), 1 is a wire to be connected, and 2 is a cut end of the wire 1. Next, the second
As shown in Figure (b), the cut ends 2 of the wire rod 1 are opposed and brought into contact with each other. At this time, a pressing force P is applied to the two wire rods 1. Next, as shown in FIG. 2(c), an electric current is passed through the wire 1, and the vicinity of the cut end 2 is melted due to resistance heat generated by the applied electric current. At this time, a pressurizing force P is applied to the two wires I, and the two wires I are pushed in sufficiently excessively to form the melted protrusion 3 as large as possible. And Figure 2 (cl)
As shown in , after the melted protrusion 3 is roughly removed using a bench or the like, the surface is finished by sanding or the like.

Problem C to be Solved by the Invention] However, in the prior art, there is a problem in that the central axis of the wire tends to shift when the wire is pushed in, and it tends to cause a jam. Further, there was also the problem that it was difficult to file the entire circumference of the melted protrusion 3 uniformly, and it was difficult to obtain a uniform cylindrical shape. For this reason, only certain skilled workers can make a good connection, which has been an obstacle to endless production of welding wires and endless use of welding wires. Particularly in the automobile industry, in order to eliminate line stops in welding processes, the use of large-capacity wound welding wires called endless packs has recently become popular, but the connection of welding wires here requires a specific skilled worker. The problem was that it could only be done well, which was a major obstacle to expanding the use of Endless Pack. Furthermore, if the entire circumference of the melting protrusion 3 cannot be sanded uniformly and becomes somewhat thick, there is also the problem that sliding current application by the contact tip of the welding torch will be hindered.

In order to solve the above-mentioned prior art, an object of the present invention is to provide a welding wire rod in which the diameter of the welded part is smaller than the average diameter of the wire rod other than the welded part, and the sliding current can be smoothly applied by the contact tip of the welding torch. .

In addition, the manufacturing method of the present invention uses a specific jig and flux to perform welding, thereby making it possible to easily connect the wire rods without misalignment of their center axes, making the welding operation easy, even by non-experts, and ensuring quality. An object of the present invention is to provide a method for manufacturing a welded wire rod that can provide an excellent connection.

[Means for Solving the Problems] In order to achieve the above object, the welded wire rod of the present invention is a welded wire rod in which at least two wire rods are welded in the length direction, and the average diameter of the wire rods other than the welded portion is and the diameter of the weld,
It is characterized in that the length of the welded portion has a relationship that satisfies the following formulas II] and [II].

0.5di<d2≦dI...[I]#<
5d, ・・・・・・
[■ (However, dl is the average diameter of the wire other than the welded part, d2 is the diameter of the welded part, and l is the length of the welded part.) Furthermore, the method for manufacturing the welded wire of the present invention can be applied to at least two wires. A method of welding wire rods using electric resistance heating, the method comprising: using a hollow heat-resistant and insulating tube; filling the hollow tube with a molten slag-forming flux; Insert the wire rod and join the tip surfaces,
Next, an electric current is passed through the wire to melt the joint by electric resistance heat generation, the wire is pushed a certain distance to perform pressure welding, and then the hollow tube and molten slag are removed.

[Function] According to the configuration of the present invention described above, the diameter of the welded portion is approximately the same or smaller than the average diameter of the wire material other than the welded portion, and the length of the welded portion is short, so that sliding by the contact tip of the welding torch is prevented. The welding wire can be a welding wire that can be smoothly energized.

Furthermore, according to the configuration of the manufacturing method of the present invention described above, a hollow heat-resistant and insulating tube is used as the cladding tube, and the wire rod is welded inside the hollow tube, so that there is no deviation of the center axis. Connection can be easily performed. Furthermore, since the gap between the inner surface of the hollow tube and the wire is filled with the flux for forming molten slag, the wire diameter of the welded portion can be finished to be approximately the same as or smaller than the original wire diameter. Furthermore, it is not particularly necessary to file the welded parts. Therefore, welding can be performed without requiring any skill.

Embodiment] An embodiment of the present invention will be described in more detail below with reference to the drawings.

Fig. 1 shows a welded wire rod according to an embodiment of the present invention (Fig. 1 (D))
, and its manufacturing method (FIGS. 1(A) to 1(C)).

In Figure 1 (D), 10.11 is a welded wire rod, 1
2 is a welded part, dl is the average diameter of the wire other than the welded part, d2 is the diameter of the welded part, and l is the length of the welded part. And these relationships are as follows.

0, 5d+ <d2 ≦d+ ・・・・
... [■ko A! <5d+...
...[II] The reason for satisfying the above formulas [I] and [II] is that in order to smoothly feed the welding wire through the welding torch on the side where it is used, the welding connection part d2 must be It is preferable that the wire diameter d+ is approximately the same as or thinner than the wire diameter d+. Therefore, the relationship d2≦d1 is satisfied. However, if the welded connection portion d2 is too thin, it will buckle at this portion, making feeding difficult. Therefore, in order to allow the wire to be fed smoothly through the welding torch, the minimum diameter dF of the connection part is
It is necessary to ensure that the wire diameter is at least half the original wire diameter d1.5゜Also, if the thin wire diameter part of the welding part is short, the interruption of current at the contact tip of the welding torch will be only a moment. Yes, there is no effect on the bead shape during arc welding. However, if it is too long, the weld bead becomes constricted, causing arc breakage instability1.The practical limit is that the length l of the weld is less than 5 times the original wire diameter d1. It is necessary.

Next, the manufacturing method of the present invention will be explained.

FIGS. 1(A) to 1(C) show the manufacturing method of the present invention. 1st
In Figures (A) to (C), 1 is a wire to be connected, and 2 is a cut end of the wire 1. The cut end may have a tapered tip, or may have a cylindrical shape of uniform thickness. 4 is a hollow heat-resistant and insulating tube (cladding tube), 5 is a welded part, 6 is a flux, and 7 is a molten slag.

Since the wire rod 1 is inserted into the tube of the cladding tube 4, it is necessary that the inner diameter d3 of the cladding tube 4 is larger than the wire diameter d1 of the wire rod 1, that is, the relationship is d3-d.

Next, the hollow heat-resistant and insulating tube (cladding tube) 4 is sufficiently filled with flux (particles) 6 for forming molten slag. As the flux (particles) 6 for forming molten slag, a slag agent such as titania or silica can be used.

A small amount of a deoxidizer such as ferromanganese or ferrotitanium may be added to the slag agent. The particle size of the slag agent is preferably fine enough to uniformly fill the gap between the surface of the wire rod and the inner surface of the cladding tube. Further, in order to prevent the flux from dissipating, a binder such as water glass containing sodium or potassium may be used to give the flux viscosity.

The cladding tube 4 may be made of a material that is slightly damaged as long as it can withstand the temperature and pressure of the molten slag without cracking. For example, ceramics having a heat resistance of about 1000° C. can also be used. In addition to alumina ceramics and zirconia ceramics, other materials include silica, which is known as a backing material for welding and a base material for cartridges for stud welding, as well as cheap heat-resistant materials based on silica, granite, and bentonite. You may also use Further, the degree of electrical insulation of the cladding tube 4 is sufficient as long as it has normal insulation (for example, a specific resistance of Ω·Cm or more) that does not impede welding due to resistance heat generation of the steel wire.

During welding operations, use flux for forming molten slag (
The wire rods 1 to be connected are inserted into both ends of the cladding tube 4 filled with particles) 6, the tips 2 of the wire rods 1 are brought into contact with each other and joined together, and the wire rods 1 are pushed in until a current can be applied. At this time, the excess flux moves through the gap between the wire rod and the cladding tube and spills out from the pipe ports on both sides, and the gap between the wire rod and the cladding tube is filled with the remaining flux without any gaps (Figure 1 (A)). . In particular, it is preferable to allow sufficient flux to exist in the gap between the contact portions of the ends of the wire so that there are no voids.

Next, an electric current is applied to the wire 1 while applying a pressure P, and the applied current melts the wire and the flux around it. Then, while continuing to energize, press the wire 1 a certain distance to make a pressure contact, and when it becomes difficult to push it any further due to the pressure of the molten metal and molten slag, or when molten slag begins to overflow from the pipe opening, energize it. and pressurization are stopped to complete welding (Fig. 1 (B)).

After welding is completed and the molten metal has solidified, the cladding tube 4
Both the molten slag and the molten slag are destroyed and removed by a mechanical impact force such as a hammer (FIG. 1(C)).

Finally, wipe the exposed wire surface with a cloth to remove any attached flux or slag, and complete the connection work.

The thickness of the finished connection part as described above is reduced by the amount of molten slag, and the diameter d2 of the welded part is always equal to or less than the original wire diameter d1.

According to the embodiment of the present invention described above, there are the following advantages.

■ Connections can be easily made without any misalignment of the central axis of the wire without requiring any skill.

■ The diameter of the welded part is approximately the same or smaller than the average diameter of the wire other than the welded part, and the sliding current can be smoothly applied by the contact tip of the welding torch.

■ No sanding is required, so you don't have to forget to shave any protruding parts.

■ Connection work can be easily performed not only by those who manufacture welded wires but also by those who use welded wires.

■ Since the connection work is easy, the large-capacity endless pack can be used not only by specific customers but also by general small-lot customers.

[Effects of the Invention] According to the present invention described above, the diameter of the welded portion is approximately the same or smaller than the average diameter of the wire other than the welded portion, and the length of the welded portion is short, so that the contact tip of the welding torch An excellent effect can be achieved in that the welding wire material can be smoothly energized while sliding.

Furthermore, according to the manufacturing method of the present invention described above, a hollow heat-resistant and insulating tube is used as a cladding tube, and the wire rods are welded inside this hollow tube, so that a connection without center axis deviation can be achieved. It can be easily implemented. Furthermore, since the gap between the inner surface of the hollow tube and the wire is filled with the flux for forming molten slag, the wire diameter of the welded portion can be made substantially the same as the original wire diameter or finer. Furthermore, it is not particularly necessary to file the welded parts. Therefore, it is possible to achieve the excellent effect of being able to weld without requiring any skill.

[Brief explanation of drawings]

FIG. 1(D) is a cross-sectional view of a welding wire according to an embodiment of the present invention;
Figures 1 (A), (B), and (C) are cross-sectional views of the same manufacturing process;
FIGS. 2(a), (b), (C), and (d) show cross-sectional views of conventional wire welding processes. DESCRIPTION OF SYMBOLS 1... Wire rod, 2... Cut end of wire rod, 4... Hollow heat-resistant and insulating tube (cladding tube), 5... Welded part,
6... Furalux, 7... Molten slag, 10.1
1... Welded wire rod, 12... Welded part. 3... Melting protrusion part 2 figure

Claims (1)

[Claims] (1) A welded wire rod in which at least two wire rods are welded in the length direction, and the average diameter of the wire rods other than the welded part, the diameter of the welded part, and the length of the welded part are as follows [I] A welding wire rod characterized by having a relationship that satisfies the formula and [II] formula. 0.5d_1<d_2≦d_1...[I]l
<5d_1...[II] (However, d_1 is the average diameter of the wire other than the welded part, d_
2 indicates the diameter of the welded portion, and l indicates the length of the welded portion. )(2)
A method of welding at least two wires using electric resistance heating, the method comprising: using a hollow heat-resistant and insulating tube;
Filling the hollow tube with a flux for forming molten slag,
Insert the at least two wire rods into the hollow tube to join the tip surfaces, then apply an electric current to the wire rods to melt the joint portion due to electric resistance heat generation, and press the wire rods by pushing them a certain distance to perform pressure welding, A method for manufacturing a welding wire, characterized in that the hollow tube and molten slag are then removed.