JPH10158669A - Arc welding chip friction-reducing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an arc welding chip friction-reducing agent for preventing a welding chip hole from being worn by friction between the welding chip and the welding wire in an arc welding by mixing an ester component with a chlorinated component and a viscosity improver in a specified ratio. SOLUTION: This agent comprises 10-70wt.% ester component, 10-70wt.% chlorinated component and 1-20wt.% viscosity index improver. The ester component is exemplified by an ester of a 3-18 C polybasic acid with a 1-18 C monohydric alcohol, an ester of a 3-22 C monobasic fatty acid with a polyhydric alcohol or an animal or vegetable oil component. The chlorinated component is exemplified by one obtained by chlorinating an animal or vegetable oil or one obtained by chlorinating a 10-30 C hydrocarbon. The viscosity index improver is exemplified by a polyalkyl methacrylate, polyisobutylene or an ethylene/a- olefin copolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arc welding tip lubricant for preventing wear of a welding tip hole caused by friction between a welding tip and a welding wire in arc welding.

[0002]

2. Description of the Related Art Conventional techniques for reducing the wear of a welding tip and a welding wire include, for example, Japanese Patent Publication No. 59-13958.
And JP-B-63-50120. These disclose welding wires having a rust preventive lubricant such as sorbitan ester, wool grease, or lanolin adhered to the surface. JP-B-63-148993 discloses a welding wire having a surface coated with a thermoplastic resin. However, even though the surface of the welding tip and the welding wire looks smooth to the naked eye, there are actually countless irregularities (surface roughness), and when the welding tip and the welding wire come into continuous contact, the surface irregularities are scraped off. Metal abrasion powder (mainly copper powder and iron powder) is generated and accumulates around the contact surface and hinders lubrication. This further promotes abrasion and creates high frictional resistance, eventually causing seizure.

[0003] Wear of a welding tip hole caused by friction between a welding tip and a welding wire as described above causes welding misalignment and insufficient bead, which is a serious problem in welding quality. For this reason, chip replacement work is frequently performed at a welding site, and the amount of used chips and the time required for replacement are enormous. Also, metal abrasion powder generated by abrasion of the welding wire when the welding wire is fed also causes a problem in that the welding arc is cut and the welding tip is clogged. However,
Under high-temperature and high-pressure conditions such as the contact area between the welding tip and welding wire, conventional rust-preventive lubricants such as sorbitan ester, wool grease, and lanolin are expected to have the effect of reducing wear and suppressing the generation of metal wear powder. In addition, if a physical protective coating made of a thermoplastic resin lacks adhesion to the metal surface, and if some of the protective coating comes off during continuous use, the generation of metal wear powder is inevitable. If it occurs, it is no longer possible to prevent acceleration of wear.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and provides an arc welding tip lubricant for preventing wear of a welding tip hole caused by friction between a welding tip and a welding wire in arc welding. The purpose is to provide.

[0005]

The present invention relates to (1) 10 to 70% by weight of the ester component, and (2) 10 to 7% by weight of the chlorinated component.
The present invention relates to an arc welding tip lubricant comprising 0% by weight and (3) 1 to 20% by weight of a viscosity index improver.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The structure of the present invention relates to a method of manufacturing a welding tip lubricant supplied between a welding tip and a welding wire.
The ester component prevents initial wear and minimizes the generation of metal wear powder, and (2) forms a coating with excellent lubrication performance by fusing with the metal wear powder in which a small amount of chlorinated components are generated and welding The purpose is to prevent wear between the tip and the welding wire. Also, by preventing abrasion, heating due to friction is reduced, and the generation of new metal abrasion powder is prevented, enabling a nearly ideal lubrication state. Furthermore, by continuously supplying the welding tip lubricant to the sliding part of the welding tip and the welding wire to maintain this effect, the welding tip lubricant is always interposed in the friction area to keep good lubrication. Is possible. In addition, the coating is resistant to pressure and heat due to the presence of the viscosity index improver (3) and maintains good performance under a wide range of temperature conditions, so that the coating continues to exert its effect even when the welding tip is heated.

[0007] The action of the ester component used in the present invention is such that the protective coating is formed by smoothly spreading and effectively adsorbing the sliding portion of the welding tip and the welding wire with other components. Is to make it easier. As the ester component, for example, a polybasic acid having 3 to 18 carbon atoms such as adipic acid, azelaic acid, sebacic acid, dodecanoic acid, trimellitic acid, and pyromellitic acid, and carbon such as 2-ethylhexanol, isodecanol, and tridecanol Esters with monohydric alcohols of formulas 1 to 18, lauric acid, myristic acid, palmitic acid, stearic acid,
Esters of linear or branched monovalent fatty acids having 3 to 22 carbon atoms such as oleic acid and isostearic acid with polyhydric alcohols such as trimethylolpropane, pentaerythritol, neopentyl glycol and dipentaerythritol; Examples include animal and vegetable oil components such as soybean oil, rapeseed oil, cottonseed oil, palm oil, castor oil, fish oil, whale oil, tallow, lard. These ester components may be used alone or in combination of two or more. It is preferable to use synthetic esters when the temperature conditions are severe or stickiness is a problem in actual use, and to use animal and vegetable oils when the welding wire feed speed and pressure conditions are severe. It is particularly preferable to use a combination of a synthetic ester and an animal or vegetable oil so that it can be applied under a wide range of conditions.

The mixing ratio of these ester components is 10 to
It is 70% by weight, preferably 30 to 60% by weight, particularly preferably 40 to 60% by weight. If the compounding ratio of the ester component is less than 10% by weight, it is not supplied stably to the sliding portion of the welding tip and the welding wire, so that lubricity is insufficient and metal wear powder is generated. If it exceeds 70% by weight, the fluidity of the arc welding tip lubricant will increase, and it will hinder adsorption to metal. The effect of the chlorinated component used in the present invention is that when the contact pressure of the contacting metal surface is extremely high, the ester component alone causes oil film breakage and causes abrasion. By doing so, a strong coating is formed on the metal surface under extreme pressure conditions to suppress the promotion of wear. That is, at the contact portion between the welding tip and the welding wire, a strong coating is formed to suppress abrasion, and a small amount of generated metal abrasion powder is wrapped with strong reactivity to act as a lubricant. In the present invention, examples of the chlorinated component include chlorinated animal and vegetable oils such as soybean oil, rapeseed oil, whale oil, beef tallow, lard and the like, and hydrocarbons having 10 to 30 carbon atoms [C _n H _{2n + 2} (n = 10-30)], and the like. The chlorine content of these chlorinated components is 3
It is 0 to 70% by weight, particularly preferably 40 to 60% by weight. When the chlorine content exceeds 50% by weight, it is preferable to use a collector for removing hydrochloric acid and an additive for preventing rust. These chlorinated components may be used alone or in a combination of two or more.

The proportion of these chlorinated components is 10 to 7
0% by weight, preferably 30 to 60% by weight,
Particularly preferably, it is 30 to 50% by weight. When the blending ratio of the chlorinated component is less than 10% by weight, the adsorbability of the welding tip and the welding wire to the sliding portion is deteriorated, and the film formation by fusion with a small amount of metal abrasion powder becomes insufficient, resulting in 70% by weight. %, Chlorine released partially causes rust of the welding wire and the material to be welded. The action of the viscosity index improver used in the present invention is characterized in that the change in viscosity of the arc welding tip lubricant is reduced even when the use temperature changes. Arc welding tip lubricant is 50-300mm to prevent dripping and scattering during application
^Although the viscosity is adjusted to ² / sec, the viscosity at the contact portion between the welding tip and the welding wire is close to 200 ° C., causing a sharp drop in viscosity, and an oil film (thickness) sufficient to suppress wear is not formed. By blending a viscosity index improver, it is possible to maintain an appropriate viscosity at the time of application and obtain a sufficient viscosity (about 4 mm ² / sec or more) to form an oil film (thickness) even at around 200 ° C. Become.

Examples of the viscosity index improver include polyalkyl methacrylate, polyisobutylene, ethylene α
-Olefin copolymers and the like. Preferred are polyalkyl methacrylates. These viscosity index improvers may be used by appropriately selecting the molecular weight so that the viscosity of the arc welding tip lubricant is 50 to 300 mm ² / sec, which is the optimum value in practical use. Usually, the molecular weight is 5,000-100,000, preferably 10,000-
30,000 can be used. The mixing ratio of these viscosity index improvers is 1 to 20% by weight, preferably 1 to 20% by weight.
It is 10% by weight, particularly preferably 3 to 10% by weight. If the compounding ratio of the viscosity index improver is less than 1% by weight, 200
If the film formation at ℃ is insufficient, and if it exceeds 20% by weight, the handling during use tends to be difficult due to the increase in viscosity, and the lubricity may be impaired.

Further, in the arc welding tip lubricant of the present invention, in addition to the above-mentioned essential components, additives such as a thickener, a rust preventive, an antioxidant, and a metal deactivator used in ordinary lubricating oil compositions. May be added as appropriate. In addition, as a method of supplying the arc welding tip lubricant of the present invention, the welding wire surface is applied with a brush or a spray device, the welding wire is immersed, and a material impregnated with the arc welding tip lubricant, for example, is passed through a felt. Any method can be used as long as it can continuously adhere to the surface of the welding wire by a fixed amount. Alternatively, any method can be used as long as a certain amount of the arc welding tip lubricant can be continuously attached to the inner surface of the welding tip, such as by immersing the welding tip and applying the welding tip inside the welding tip hole with a small diameter spray device. In order to continuously adhere them, they may be supplied without interruption, or may be supplied continuously at fixed time intervals. The supply amount of the arc welding tip lubricant is preferably 0.01 to 0.1 ml per 10 m of the feeding amount of the welding wire. If the amount is less than 0.01 ml, the effect is small. If the amount exceeds 0.1 ml, the excess drips from the welding wire, polluting the surroundings, and is economically disadvantageous.

[0012]

Next, the present invention will be described more specifically with reference to examples and comparative examples. The present invention is not limited by these examples. Example 1 Trimethylolpropane trioleate (trioleate) and rapeseed oil were 30% by weight and 20% by weight, respectively, as ester components, and chlorinated lard oil and chlorinated paraffin having a chlorine content of 50% by weight were used as chlorinating components. An arc welding tip lubricant was prepared by heating and mixing 20% by weight and 25% by weight, respectively, and a polyalkyl methacrylate as a viscosity index improver at 5% by weight at 60 to 80 ° C. The lubricating performance and antifriction performance of this arc welding tip lubricant were examined under the following test conditions. Tester: Ohkoshi formula [Model OAT-U] specimen material: chromium copper (1% Cr) specimen geometry: 10t × 25 × 50 mm Friction rate: 10.38m / min, maximum load: 53kg / cm ^2,
Friction time: 6.4 min, Supply method: 1 ml was dropped with a microsyringe between the rotating disk and the test piece immediately before the start of the test. The width of wear marks measured in the above test is shown in Table 1 and FIG. The following lubricants were used as comparative examples. Comparative Example A Mineral oil (viscosity of 100 mm ² / S at 40 ° C.) blended with 10% by weight of a polyethylene resin (particle diameter: 1 to 20 μm) Comparative Example B Trimethylolpropane triolate (30
8% by weight of chlorinated paraffin in rapeseed oil (20% by weight) and rapeseed oil (20% by weight)

[0013]

[Table 1]

From the results shown in Table 1 and FIG. 1, the arc welding tip lubricant of the present invention has shifted to a stable wear preventing state through the process of forming a protective coating for preventing wear on the rotating disk surface. In the first test, the copper powder has already been generated at the frictional portion between the rotating disk and the test piece, but the wear mark width decreases with each repetition. On the other hand, in the case of Comparative Example A, the width of the first wear mark is equal to that of the example, but the width of the wear mark tends to increase with each repetition. This is because the main lubrication mechanism of Comparative Example 1 is due to the coating of the physical protective film, and the wear prevention effect is reduced due to the generation of copper powder due to the progress of wear and the roughening of the surface of the friction portion of the rotating disk. . In the case of Comparative Example B, the wear prevention effect is lower as a whole than in the Examples,
Not enough.

Example 2 A bottle containing the arc welding tip lubricant of the present invention, prepared in the same manner as in Example 1, was attached to the front of the welding wire feeding roller, and was attached to the actual welding wire by absorbent weight through absorbent cotton. The diameter of the welding tip hole after use when supplied and applied was measured. The welding conditions and criteria are shown below. Welding wire feeding speed: 10m / min, welding current: 280
A, welding time (accumulated): 80 hours, lubricant supply: 0.1
Adjusted to 03 ml / 10 m. Judgment criteria: The hole diameter of the welding tip after use is less than 1.7 mm. If it is larger than this, welding misalignment and bead failure occur, causing problems in welding quality. Table 2 shows the welding tip hole diameters measured in the above test.
Tables 3 and 4 show the results of the analysis of variance.

[0016]

[Table 2]

[0017]

[Table 3] Analysis of variance: One-way layout Overview

[0018]

[Table 4] Analysis of variance table

From Table 2 and the results of the analysis of variance, the data is highly significant, indicating that the arc weld tip lubricant of the present invention was 8%.
Even after 0 hours, the 1.6mm level of the passing line has been secured.
On the other hand, in the case of Comparative Example A, the main lubrication mechanism is based on the coating of the physical protective film, and the surface of the frictional portion due to copper powder or iron powder generated by the progress of wear due to friction between the welding tip and the welding wire. It can be said that the wear prevention effect has been reduced by the roughness. In the case of Comparative Example B, the abrasion prevention effect was low as a whole as compared with the Example of the present invention, and it can be said that it was insufficient.

Example 3 In order to estimate the use limit of a welding tip, the supply amount of the arc welding tip lubricant of the present invention prepared with the same composition as in Example 1 was applied to welding wires for five actual welding robots. Pumps and piston-type distributors automatically supply evenly 0.015 ml / 10 m to a felt cylinder provided in the path of each welding wire, and the longest repeated welding cycle 1
The data of four shifts (112 hours) were taken, and the diameter of the welding tip hole after use was measured. In addition, the feed amount of welding wire per line (8 hours) is 650 m, and when the arc welding tip lubricant is not used, the diameter of the welding tip hole is 1.7 m per line.
It has exceeded m and has been replaced. The same welding conditions as in Example 2 were employed. Table 5 and FIG. 2 show the welding tip hole diameters measured in the above test, and Tables 6 and 7 show the results of the analysis of variance.

[0021]

[Table 5]

[0022]

Table 6: Analysis of variance: two-way configuration without repetition

[0023]

[Table 7] Analysis of variance table

From Table 5, FIG. 2, and the results of the analysis of variance, the hole diameter wear of the welding tip has a very strong correlation with the feed amount of the welding wire, and the supply of the arc welding tip lubricant of the present invention was effective in suppressing the wear. It turns out that it is very effective. In addition, when the welding wire is fed at 9000 m by the supply of the arc welding tip lubricant, the welding tip hole diameter is 1.7 mm.
This corresponds to 3.8 times, and it is possible to suppress the wear by 13 times or more as compared with the case where the arc welding tip lubricant is not used.

[0025]

According to the present invention, the lubricating film resistant to pressure and heat is formed on the inner wall of the welding tip and the surface of the welding wire at the initial stage by entering the sliding portion of the welding tip and the welding wire. The effect of minimizing the generation of powder can be maintained. Further, the generated metal abrasion powder is incorporated into the lubricant, so that the promotion of abrasion can be prevented. ADVANTAGE OF THE INVENTION According to the arc welding tip lubricating agent of this invention, it can reduce welding arc problems and welding tip clogging due to welding quality problems such as welding misalignment, bead failure, and metal abrasion powder by suppressing wear of the welding tip. it can. This creates a lubricating state that is close to ideal, which makes it possible to increase the diameter of the hole due to wear of the welding tip, suppress deformation, and improve the feedability of the welding wire. And the number of man-hours spent for replacement work can be reduced.

[Brief description of the drawings]

FIG. 1 is a graph showing the width of a wear mark in a wear test of Example 1.

FIG. 2 is a graph showing a relationship between a hole diameter of a welding tip and a feed amount of a welding wire in a welding test of Example 3.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takao Soda 1-2-1915 Takasu-cho, Nishinomiya City, Hyogo Prefecture

Claims (1)

[Claims] 1. An arc welding tip lubrication comprising (1) 10 to 70% by weight of an ester component, (2) 10 to 70% by weight of a chlorinated component, and (3) 1 to 20% by weight of a viscosity index improver. Agent.