JP3219978B2 - Conduit liner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conduit liner for guiding a wire provided between a feed roller of a wire supply device and a welding tip in a welding device.

[0002]

2. Description of the Related Art A conduit liner is provided between a feed roller of a wire feeder and a welding tip and guides a wire to the welding tip. The conduit liner is also called a conduit tube, a spring liner, or a liner. Also, this includes an inner tube disposed inside the torch portion. 3 and 4 show an example. FIG. 3 shows an arrangement state of a conduit liner, and FIG. 4 shows a partial cross section of a generally used conduit liner. In FIG. 3, the wire supply device 4 includes a spool 3 around which the wire 1 is wound and a feed roller 2 for feeding the wire 1. The wire 1 fed from the feed roller 2 is guided in the conduit liner 5 and reaches the welding torch 6. A welding tip 7 is provided at the tip of the welding torch 6. A welding current is applied to the wire 1 from the welding tip 7 to emit a welding arc 8 to weld the workpiece 9.

[0003] The conduit liner 5 is required to have the flexibility to be able to follow the movement of the welding torch 6 smoothly and bend in a free direction, and to have a small outer diameter and a light weight. desired. Therefore, the conduit liner 5 is formed by spirally winding the metal wire 10 without any gap as shown in FIG. The inner diameter of the conduit liner is about 0.5 mm larger than the outer diameter of the wire 1 for ease of wire feeding.

In recent years, a conduit liner having a length of 6 to 20 m has been used due to the diversification of welding structures and an increase in welding efficiency, etc., in order to adjust the distance from a wire feeder to a welding site. It is often used by being bent to the left or right, or wound in a loop to adjust its length. Further, in a narrow welding site, a conduit liner immediately before a welding torch is often used by bending it into an S-shape or a J-shape. In this case, when the conduit liner is bent, the wire passing through the inside is pressed against the inner surface of the conduit liner, and the contact friction portion increases.

[0005] For this reason, a lubricant is generally applied to the surface of the wire. However, depending on conditions, the wire feed resistance in the conduit liner may cause the wire to slip by the feed roller, causing an arc to break, etc. It may not be possible.
Also, since the wire is strongly rubbed in the conduit liner, the clogging of the wire and the condensed liner in the conduit liner is promoted.In addition, the feed resistance is increased and welding becomes difficult, and the frequency of replacing the conduit liner is increased. This has caused many.

As a countermeasure for reducing the wire feeding resistance by the conduit liner, for example, Japanese Patent Publication No. 4-24146 discloses a method of rotating the conduit liner. However, the apparatus becomes complicated, and equipment costs and costs are reduced. Get higher.
Japanese Patent Application Laid-Open No. 63-194873 discloses a method of providing a coating layer made of a substance having excellent wear resistance and lubricity in a conduit liner. However, the cost of the conduit liner increases and the coating layer becomes expensive. Because the thickness of the coating layer is thin, it is not possible to maintain good feedability due to wear of the coating layer,
There are problems such as the need to frequently replace the conduit liner. Japanese Patent Publication No. 24189/1990 discloses that the metal wire of the conduit liner inserted into the curved portion of the welding torch is loosely wound in order to prevent vibration of the conduit liner in the welding torch. Since the length is very small, it is not possible to sufficiently reduce the feeding resistance.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention provides a wire liner having good wire feedability and low abrasion even when the conduit liner is long and used in a bent shape such as up and down, left and right or S-shaped or J-shaped. It is an object of the present invention to provide a conduit liner that is economically excellent, for example, without accumulating debris from the wire or the conduit liner and reducing the frequency of replacement of the conduit liner.

[0008]

In order to achieve the above object, the inventors of the present invention have made various prototype liners and have conducted experiments. As a result, when the spacing between the spirally wound metal wires is small, the present inventors have found that. It has been found that when used in a bent state, the frictional resistance increases, which greatly affects the wire feedability and the durability of the conduit liner. That is, the gist of the present invention is that in a conduit line for feeding a welding wire formed by spirally winding a metal wire, the winding interval of the metal wire is set to 0.2 to 1.4.
mm . In addition, the interval between the metal windings of a part or all of the portion bent during welding is 0.2 to
It is characterized by being 1.4 mm .

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
FIG. 1 shows an example of a partial cross-sectional view of a conduit liner in which a metal wire of the present invention is spirally wound. By setting the winding interval G of the metal wire to 0.2 to 1.4 mm as shown in FIG. 1, when the conduit liner 5 is used in a long shape, which is bent up and down, left and right, or S-shaped or J-shaped. Also, the contact point interval between the wire and the conduit liner is widened, the film of the lubricating oil applied on the wire surface is not easily broken, the wire feedability is good, the wear is small, and the wire and the conduit liner 5
This makes it possible to obtain a conduit liner that is economically excellent, for example, without accumulating the exfoliated matter and reducing the frequency of replacing the conduit liner.

When the winding interval G of the metal wire is less than 0.2 mm , the contact portion of the wire with the conduit liner at the time of wire feeding increases, the wire feeding resistance increases, and the wear of the wire and the conduit liner increases. As a result, the exfoliated matter accumulates in the conduit liner, further increasing the wire feed resistance and making welding difficult. When the winding interval G of the metal wire exceeds 1.4 mm , the contact surface pressure between the wire and the conduit liner increases, the film of the lubricating oil tends to break, and the wire feeding resistance increases. Also,
When first passing the wire tip through the conduit liner,
There is a case where the wire tip enters the winding interval G of the metal wire and the wire cannot be inserted to the welding tip.

When the length of the conduit liner is Lm, the diameter of the metal wire is dmm, and the winding interval is Gmm, the number N of points where the wire and the conduit liner come into contact is 1000 × L /
(D + G), and the ratio a to the number N of contact points when the winding interval G is 0 mm is d / (d + G). Assuming that the wire diameter d of the metal wire is 1.6 mm, if G is 0.5 mm, a
= 0.76, when G is 1.0 mm, a = 0.62, and when G is 2.0 mm, the number of points in contact with a = 0.44 is greatly reduced. However, when the number of contact points decreases, the contact pressure between the wire and the conduit liner increases.

Further, since the position of the conduit liner that comes into contact with the wire is mainly at the bent portion of the conduit liner, in a contact device or a welding robot where the bent portion of the conduit liner is always at the same position, the conduit liner is bent. Part or all of the metal wire winding interval
By setting the thickness to 0.2 to 1.4 mm , the wire feedability is good, the friction is small, the peeled material of the wire and the conduit liner does not accumulate, and the frequency of replacing the conduit liner is reduced.

As described above, the present invention reduces the wire feed resistance by increasing the winding interval of the conduit liner within a range that does not interfere with the number of contact points between the wire and the conduit liner. Is what you do. Therefore, the conduit liner of the present invention and the wire to be used can be applied as long as the material and dimensions are generally used.
That is, the wire is made of ordinary steel, low alloy steel plated with copper, stainless steel or the like, and has an outer diameter of 0.9.
２．０2.0 mm. Conduit liners are made of plain steel zinc plated, nickel plated, cadmium plated, stainless steel, etc.
The dimensions are such that the outer diameter of the metal wire is 0.8 to 3.0 mm.

[0014]

The present invention will be described in more detail with reference to the following examples. First, various types of conduit liners having a length of 6 m shown in Table 1 were prototyped, and two loops each having a diameter of D80 mm were connected to the welding liner shown in FIG.
It was installed to increase the bending. The bending radius of the welding torch portion was 80 mm. As the conduit liner, a 0.7% carbon steel wire drawn and galvanized to a metal wire having an outer diameter of 1.6 mm and a hardness of Hv500 was used. The test wire had a surface coated with 0.4 to 1.0 g of palm oil as a lubricating oil per 10 kg of wire according to JIS Z.
A 3313 YFW-C50DR 20 kg spool wound flux cored wire having a diameter of 1.2 mm was used, and each conduit liner weighed 15 kg under the following welding conditions.
Welded.

Welding current: 270 A Welding voltage: 28 V Welding speed: 15 cm / min Wire protrusion length: 20 mm Shielding gas: CO ₂ 20 l / min Welding method: Bead-on plate A load is applied to the wire 1 sent from the spool 3 The feed roller 2 is retracted, and the force generated at the feed roller 2 at this time was measured by the load cell 11 as a feed resistance R. The feed resistance R within the range where stable welding can be performed is 6
kg or less. Table 1 shows the results of the welding.

[0016]

[Table 1]

In Table 1, No. 1 to No. 1; 7 is an example of the present invention, N
o. 8 to No. 13 is a comparative example. No. of the present invention. 1
~ No. 7 is the winding interval of the metal wire of the entire conduit liner, the loop portion of the conduit liner or the torch portion.
Since it is 0.2 to 1.4 mm , the contact point interval between the wire and the conduit liner is widened, the lubricating oil applied on the wire surface is hardly cut, and the wire feed resistance R
However, the arc condition is stable at 5kg or less and extremely
And good results. After the welding, the conduit liner was cut and examined, and as a result, the amount of peeled wire and conduit liner was very small.

In the comparative examples, No. No. 8 indicates that the entire conduit liner is no . No. 10 is a loop part, and No. 10 In No. 12, since the metal wire winding interval of the torch portion is less than 0.2 mm , the contact portion between the welding wire and the conduit liner increases, the feed resistance R increases, and the arc becomes unstable. became. As a result of cutting and examining the conduit liner at the loop portion after welding was completed, there were many peeled off wires and the conduit liner.

No. in the comparative examples . No. 9 indicates that the entire conduit liner is no . No. 11 is a loop part, and No. 11 No. 13 shows that the contact surface pressure between the welding wire and the conduit liner becomes large because the metal wire winding interval of the torch portion exceeds 1.4 mm, and the film of the lubricating oil of the wire breaks,
Each of the feed resistances R increased, and the arc became unstable. In addition, No. 9 and no. In the case of No. 11 , when the wire tip was first passed through the conduit liner, the wire tip entered the winding interval G of the metal wire and the wire could not be inserted to the welding tip, so the loop was extended and inserted.

[0020]

As described above, according to the conduit liner of the present invention, even when the conduit liner is long and used up and down, left and right, or bent into an S or J shape, the wire feedability is improved. It is possible to provide a conduit liner that is excellent in economy, has little wear, does not accumulate the peeled material of the wire and the conduit liner, and has a low exchange frequency of the conduit liner.

[Brief description of the drawings]

FIG. 1 is a diagram showing a cross section of a conduit liner of the present invention.

FIG. 2 is a diagram showing a bending condition of a conduit liner used in an embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing a configuration of a welding device.

FIG. 4 is a view showing a cross section of a conventional conduit liner.

[Explanation of symbols]

 1 Wire 2 Feed roller 3 Spool 4 Wire feeder 5 Conduit liner 6 Welding torch 7 Welding tip 8 Welding arc 9 Workpiece 1 0 Metal wire 1 1 Load cell D Loop diameter

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ichiro Masuda 3-5-4 Tsukiji, Chuo-ku, Tokyo Nippon Steel Welding Industry Co., Ltd. (72) Inventor Takeji Kagami 4-2-1 Asae, Hikari-shi, Yamaguchi Prefecture No. Nippon Steel Welding Industry Co., Ltd. Hikari Factory (72) Inventor Hideo Nozawa 1509 Okubo-cho, Hamamatsu-shi, Shizuoka Prefecture Tokin Corporation (56) References JP-A-48-71347 (JP, A) Akira Mikai 58-17976 (JP, U) Japanese Utility Model Showa 58-157271 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23K 9/133

Claims (2)

(57) [Claims] 1. A conduit liner for feeding a welding wire formed by spirally winding a metal wire, wherein the interval between windings of the metal wire is 0.2 to 1.4 mm . 2. A conduit liner for feeding a welding wire formed by spirally winding a metal wire, wherein a part or all of a metal wire winding interval of a part bent at the time of welding is 0.2.
A conduit liner characterized in that the diameter is 1.4 mm .