JP2000117486A - Welding wire and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a wire having an excellent feeding property even under such an opening environment that feeding resistance becomes high and further, even under a wide operating temperature from a low temperature to a high temperature by applying a feeding solid lubricant and feeding lubricating oil having a specified pour point and an iodine value to a surface. SOLUTION: Feeding lubricating oil having a pour point of <=5 deg.C and an iodine value of <=40 is stuck. Preferably, synthetic ester oil of >50 wt.% having a neopentylpolyolester structure, wherein the feeding lubricating oil is composed of one kind or more of an alcohol part selected from neopentylglycol, trimethylolpropane and pentaerythritol and a fatty acid part containing saturated fatty acid of >=50 wt.% having the number of carbon of 12-14, is contained to the total quantity of the feeding lubricating oil. A feeding solid lubricant is composed of one kind, two kinds or more of MoS2, WS2, polytetrafluoroethylene and graphite. Also, the sticking quantity of the feeding solid lubricant is made to 0.01-2 g per wire 10 kg and the sticking quantity of the feeding lubricating oil is made to 0.1-1.5 g per wire 10 kg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire for arc welding such as a flux-cored wire and a solid wire for fully automatic and semi-automatic welding, and a method for producing the same.

[0002]

2. Description of the Related Art Generally, CO ₂ gas shielded arc welding,
For MIG welding or the like, a welding wire having a small diameter (0.8 to 1.6 mmφ) is used. The welding wire is provided for welding in a form wound on a spool or loaded in a pail pack. When using this welding wire, the feed roller of the feeder pulls out the wire from the spool or pail pack and pushes it into the liner contained in the subsequent conduit cable. A method is used in which the power is fed up to the power supply tip in the attached welding torch. A voltage is applied to the wire between the power supply tip and the material to be welded, and arc welding is performed.

[0003] The conduit liner used here is a flexible guide pipe formed by spirally forming a steel wire, and its length is usually about 3 to 6 m, but is 10 to 20 m when a wide area is welded. It becomes a long thing,
Select and use according to the distance to the welding point. According to this method, there is an advantage that welding can be performed relatively easily along a conduit cable (liner) even in a place where a welding place is narrow or has a height difference such as a shipbuilding site.

However, the following problems may occur during use, and there is a demand for solving them. In order to perform stable welding, it is necessary to supply the welding wire to the welded portion at a predetermined constant speed, that is, it is necessary that the feedability is good. The wire is pushed into the liner by the feed force of the feed roller, while receiving a feed resistance from the inner surface of the liner due to contact friction. At this time, in a relatively gentle use environment where the liner is close to a straight line, the feed resistance is not so large and there is no problem in feedability, but there are many bent portions and the bent radius (curvature radius) is small. Or, in a severe use environment such as when the liner is lengthened, the feeding resistance increases, the balance with the feeding power is broken, and the feeding property is deteriorated.

[0005] The surface condition of the wire greatly affects the quality of the feedability. That is, when the feed resistance increases,
If the amount of the lubricant on the surface of the wire is small, the feeding speed becomes unstable and varies, so that the feeding property is deteriorated. In addition, the wire buckles in the liner, the surface of the wire is shaved due to the deterioration of the feed roller, and the shavings enter and accumulate in the liner, thereby increasing the feed resistance.
Conversely, if the amount of the lubricant on the wire surface is large, the feed roller slips excessively, and the wire cannot maintain a predetermined feed speed, and the feedability deteriorates. As a result, problems such as instability of the welding arc, irregularity of the bead shape, poor fusion, and occurrence of undercut occur. There is almost no welding site where the conduit cable is used in a straight line, and it is common to weld the work while bending the cable in a complicated and complicated place. Welding wires have become strongly required.

Conventionally, various lubrication treatments have been performed on the surface of a welding wire in order to ensure the feedability. For example, Japanese Patent Publication No. 50-3256 discloses a welding wire in which lubricating oil is applied to a dense and smooth surface. However, if the wire surface is dense and smooth, it is difficult to apply a predetermined amount of lubricating oil evenly and stably, and in order to obtain a wire with good feedability, it is necessary to apply a large amount of lubricating oil. Absent. However, wires with a large amount of lubricating oil on the surface are difficult to cope with bending of the liner, etc., as described above, because the feed roller tends to slip due to an increase in feed resistance, as well as poor welding workability and diffusible hydrogen. There is a drawback in that the quality of the weld metal is deteriorated due to the increase in the amount.

On the other hand, as an example of using a solid lubricant, Japanese Patent Application Laid-Open No. 50-146541 discloses a method for producing a composite wire for welding, which comprises a single or mixture of molybdenum disulfide powder and graphite powder and one or more flux components. A method for producing a composite wire for welding, characterized in that the wire is drawn by a wire drawing agent containing a mixture of the above as a main component. Japanese Patent Application Laid-Open No. 58-135,955 discloses that one or both of graphite and molybdenum disulfide and 10
６０60% by weight of a mixture of glass powder, and the amount of the lubricant is 5 × 10 ^{−2 to} 5 × 10
^A wire for arc welding characterized by ^-2 % is disclosed.

[0008] However, it is difficult to control the amount of lubricant adhering with the above-mentioned technology, and there are problems in that a portion where the lubricant adheres excessively occurs and the lubricant adheres unevenly after drawing. If the lubricant is excessively adhered, clogging may occur in the conduit cable, making it difficult to feed. Further, if the lubricant is unevenly attached, it becomes difficult to perform stable feeding. Therefore, a technique has been proposed in which the lubricating oil is applied evenly and stably in the longitudinal direction of the wire by increasing the roughness of the wire surface and holding the lubricating oil in the recess. For example, Tokuho 4-521
No. 97, JP-B-58-56677 discloses a manufacturing technique for increasing the roughness of the wire surface.
Further, the problem of deterioration of the feedability caused by the deterioration of the lubricating ability due to the low-temperature viscosity deterioration of the feed lubricating oil in winter, severe cold regions, etc. cannot be ignored.

[0009]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a harsh condition in which a specific feeding lubricant (solid lubricant + lubricating oil) is applied to the surface of a wire to increase the feeding resistance due to bending of a liner or the like. It is an object of the present invention to provide a welding wire capable of exhibiting good feedability even in a working environment and a wide range of operating temperatures from low to high temperatures, and a method for manufacturing the same.

[0010]

The gist of the present invention is as follows: (1) The solid lubricant to be fed and the lubricating oil having a pour point of 5 ° C. or less and an iodine value of 40 or less are attached. In the welding wire. (2) The feed lubricating oil comprises at least one alcohol part selected from neopentyl glycol, trimethylolpropane, and pentaerythritol, and a fatty acid part containing 50 wt% or more of a saturated fatty acid having 12 to 14 carbon atoms. The welding wire according to the above (1), wherein a synthetic ester oil having a neopentyl polyol ester structure is contained in an amount of 50 wt% or more based on the total amount of the lubricating oil fed. (3) The welding as described in (1) or (2) above, wherein the solid lubricant to be fed is composed of one or more of MoS ₂ , WS ₂ , polytetrafluoroethylene, and graphite. On the wire.

(4) The amount of solid lubricant to be supplied is
(1) to (3) the welding wire according to (1) to (3), wherein the amount of the lubricating oil supplied is 0.1 to 1.5 g per 10 kg of the wire. . (5) Perform dry drawing with the supplied solid lubricant, and then at least the final die has a pour point of 5 ° C or less and an iodine value of 4
A method for manufacturing a welding wire, characterized in that the wire is finished to a predetermined diameter by performing wet drawing using a lubricating oil of 0 or less.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the contents of the present invention will be described in detail. In the present invention, the supplied solid lubricant is attached to the surface of the welding wire. Here, the supplied solid lubricant is MoS ₂ , WS
_2. One or more of polytetrafluoroethylene (hereinafter, referred to as PTFE) PTFE and graphite. These feed solid lubricants adhere to the wire surface, reduce the coefficient of friction between the inner wall of the conduit liner and the wire, and suppress the increase in feed resistance, ensuring good feedability of the welding wire. .

[0013] The amount of solid lubricant fed is 0.01 to 2.0 g per 10 kg of wire in order to exhibit the above-mentioned effect.
(G / 10 kgW). 0.01g / 10
If it is less than kgW, no effect of suppressing an increase in the feeding resistance is recognized, and no improvement in the feeding property can be expected. Conversely, if it exceeds 2.0 g / 10 kgW, it will be excessively adhered to the wire surface, the feed roller will slip greatly, and stable feed will be difficult. In addition, the inside of the conduit liner becomes dirty, and a feeding failure due to a clogged lubricant occurs.

The solid lubricant to be fed can be adhered to the wire surface by being contained in the dry lubricant used in the dry die drawing during the manufacturing process. The dry lubricant may be the same as that generally used for wire drawing, and is composed of powdered metallic soaps, inorganic substances, wax, or the like. As the metal soap, sodium stearate, sodium oleate, barium stearate, lithium stearate, calcium stearate, magnesium stearate, zinc stearate, aluminum stearate and the like can be used. As the inorganic substance, talc, titanium oxide, lime, borax and the like are used. Some of these dry lubricants, along with the solid lubricant delivered, adhere to the surface of the product wire.

[0015] In terms of the function of each component of the dry lubricant, metal soap has a function of reducing the coefficient of friction during wire drawing, and inorganic substances similarly draw metal soap into the die during wire drawing. Has the function of a carrier for
Further, the wax has a function of firmly attaching the fed solid lubricant to the wire surface. Further, the solid lubricant fed as an additive component, which is a feature of the present invention, can be effectively used as an isodrawing lubricant having an effect of reducing a friction coefficient at the time of wire drawing, in addition to the above-described effect of improving the feedability of the product. Works.

It is desirable that the content of the solid lubricant fed during the dry lubrication is 5 to 60%. If the amount is less than 5%, it becomes difficult to secure the amount of adhesion, and if the amount exceeds 60%, the effect is the same, which is economically disadvantageous. In the present invention, feed lubricating oil adheres to the surface of the welding wire. The feed lubricating oil adheres to the entire surface of the wire, thereby supplementing the lubricating action of the feed solid lubricant.

The lubricating oil of the present invention has a pour point of 5 ° C. or less,
The iodine value is 40 or less. The feed lubricating oil has the effect of reducing the coefficient of friction during wire drawing, and has the effect of adhering to the surface of the welding wire together with the solid lubricant to improve the feedability of the welding wire. If the pour point of the lubricating oil is in the range of 5 ° C. or less, good feedability can be obtained without any influence on the chemical structure. It can be used in a normal temperature range of about 10 to 30 ° C., and particularly has a low flowability due to its good low-temperature fluidity.
Excellent feedability in low temperature range below ℃.

Further, the lubricating oil of the present invention has the effect of washing the solid lubricant which has excessively adhered during the wire drawing process to make the amount of the lubricant proper and to make the amount more uniform. It is desirable that the iodine value of the supplied lubricating oil be 40 or less. The iodine value is an index of the oxidation resistance of the lubricating oil to be fed. If the iodine value exceeds 40, oxidative polymerization / polymerization of the fatty acid easily proceeds due to heat and aging. As a result of the progress of oxidative polymerization and polymerization, the pour point of the supplied lubricating oil increases,
Stable feeding will not be performed.

The lubricating oil used in the present invention has a neopentyl polyol ester structure, the alcohol part is at least one selected from neopentyl glycol, trimethylolpropane, and pentaerythritol, and the fatty acid part has 12 carbon atoms. It is desirable that the synthetic ester oil containing 50 to 14% by weight of the saturated fatty acid is 50% by weight or more based on the total amount of the lubricating oil to be fed.

The neopentyl polyol ester is preferably used as a feed lubricating oil because the alcohol controlling the properties of the oil is a hindered type having a neo skeleton, so that it is chemically stable and the degree of bending of the liner is high. This is because they have excellent lubricating properties under harsh environments such as large lubrication. Since the fatty acid portion is a synthetic ester containing 50 wt% or more of a saturated fatty acid having 12 to 14 carbon atoms, the lubricating ability can be maintained and the pour point of the supplied lubricating oil can be maintained at 5 ° C. or lower. Good feedability can be exhibited even below. Carbon number 1
It is difficult to maintain the pour point at 5 ° C. or less when the content of saturated fatty acids exceeding 4 is 50 wt% or more, and the lubricating ability is insufficient when the content of the saturated fatty acids having less than 12 carbon atoms is 50 wt% or more. Therefore, stable feeding property cannot be obtained. The structural formula of neopentyl glycol ester is shown below as an example of neopentyl polyol ester.

[0021]

Embedded image

The synthetic ester oil is used in an amount of 50 wt% or more based on the total amount of the lubricating oil to be fed, and may be used in combination with another lubricating oil (hereinafter, referred to as added lubricating oil). Mineral oil, animal and vegetable oils, and synthetic oils can be used as the added lubricating oil. Machine oil, turbine oil, spindle oil and the like can be used as mineral oil, and palm oil, rapeseed oil, coconut oil, castor oil, pork oil, cow oil, fish oil and the like can be used as animal and vegetable oils. As the synthetic oil, a hydrocarbon oil, an ester oil, a polyglycol oil, a polyphenol oil, a silicone oil, a fluorocarbon oil, or the like can be used.

In order to further improve the lubricating performance, a lubricating agent such as various fatty acids or a phosphorus-based, chlorine-based or sulfur-based extreme pressure additive may be added to the lubricating oil to be fed. An additive (antioxidant) for preventing oxidation of oil may be added. The addition amount of these is 0.1 to 5.0 wt%
Good results can be obtained. The amount of lubricating oil supplied on the surface of the welding wire is 0.1 to 10 kg / wire.
It is desirably 1.5 g (g / 10 kgW).
When the amount is less than 0.1 g / 10 kgW, the lubricating action of the fed solid lubricant is small and the feeding property is not improved. Conversely, 1.
If it exceeds 5 g / 10 kgW, it will adhere excessively to the wire surface, and the feeding roller will easily slip. Further, since the lubricating oil is decomposed by the welding heat to generate a large amount of hydrogen, deterioration of the weld metal material due to an increase in the amount of diffusible hydrogen is likely to occur.

The present invention is applicable to any welding wire including a solid wire in a solid state and a flux-cored wire (with or without seam) in which a flux material is included in the wire. In addition, any plating wire or non-plating welding wire is also targeted. The welding wire of the present invention is manufactured, for example, as follows. The solid lubricant of the present invention is rubbed and adhered to the welding wire manufactured by the predetermined process, and thereafter, the wet die drawing is performed. If the number of wet dies is more than one, feed lubricating oil is used at least in the last die. Dry die drawing is performed with a dry lubricant containing the solid lubricant of the present invention, and then wet die drawing is performed to finish to a predetermined product size. If there are multiple wet dies,
Use feed lubricant at least in the final die.

In the case where the reduction of the wet die drawing is as large as 70% or more, a cassette type roller die (CRD) drawing is interposed between the dry die drawing and the wet die drawing, and the wet die drawing is performed. To reduce the reduction. As a result, it is possible to prevent a decrease in roughness in wet die drawing and a decrease in the attached amount of the feed lubricant. In any case, the feed lubricating oil may be applied by applying electrostatic oil while running the wire after drawing to the product size, or by sandwiching the wire with an oil-impregnated felt.

Here, a production example will be described with reference to a schematic view of the entire production line shown in FIG. (A) is a supply unit of the wire strand 1, wherein a plated wire or a non-plated solid wire or a flux-cored wire is used as the wire strand 1. Wire diameter is 2.0 to 5.0
mmφ and the surface roughness is JIS B0601
It is preferable that the measured value in the longitudinal direction of the wire (hereinafter referred to as Ra [L]) is 0.3 μm or more with a roughness Ra specified in -1994. This is to make it easier for the fed solid lubricant to adhere to the surface of the wire 1.

The wire 1 drawn from the supply unit (A) is
In the dry drawing step (B), dry die drawing is performed using a dry lubricant containing a solid lubricant to be fed. The dry lubricant is pushed into and held by the hole die 2 in the concave and convex portions of the wire surface. Subsequently, the wire enters a CRD drawing step (C). The CRD uses a plurality of small-diameter roller pairs to rotate the rotating shaft 90 degrees from each other.
Cassette type roller unit (corresponding to one hole die) 3 (3-1, 3-2, 3-2)
3-3, 3-4), and 1 according to the set reduction.
The wire is reduced to a predetermined size using one or more units. 4 indicates a take-up capstan. In the wire drawing by the CRD rolling process, there is no or very little attenuation of the roughness due to the dry lubricant confined in the concave portion of the wire surface. That is, the feed lubricant is sufficiently held in the concave portion on the wire surface.

The wire reduced in diameter to a predetermined size by CRD drawing enters a wet die drawing step (D). The wire is drawn by a multi-stage slip-type wet drawing machine 5, and finally drawn to a product size 7 by a final finishing die 6 using the lubricating oil of the present invention (E). In the wet drawing process by drawing a hole die, the amount of dry lubricant in the recesses on the surface of the wire decreases, and the roughness also decreases accordingly. The reduction distribution between the CRD and the wet drawing is adjusted in advance so that the drawing is finished in a size that can secure the amount. The wet die drawing step also has a cleaning action to remove excess dry lubricant and dirt adhering to the wire surface.

The product size is about 1.0 to 2.0 mm. The surface roughness of the welding wire thus manufactured is desirably about Ra [L] = 0.07 to 0.20 μm. If the roughness is less than 0.07 μm, it is difficult to secure the adhesion of the feeding lubricant (solid lubricant + lubricating oil) necessary for the feeding property. Conversely, if the roughness exceeds 0.20 μm, the amount of the feeding lubricant becomes excessive. Even with a small feeding resistance due to adhesion, the wire slips greatly, making it difficult to obtain a predetermined feeding speed.

[0030]

EXAMPLES The effects of the present invention will be specifically described below with reference to examples. Finishing diameter (product diameter) according to the process shown in FIG.
1.4φ flux cored wire (JIS Z331
3) YFW-C50DR, flux filling rate 15%) and a solid wire (JIS Z3312 YGW11) were prototyped, and the surface properties and feeding performance of the prototype (spool wound wire) were investigated. The roughness of the surface properties was measured by Ra [L] using a stylus profilometer (needle tip 5 μmR), and the amount of oil and the amount of solid lubricant attached were analyzed by chemical analysis (toluene / ether extraction method).
Was measured by Table 1 shows the experimental conditions.

[0031]

[Table 1]

The feeding evaluation test was carried out using the apparatus shown in FIG. In FIG. 2, the spool winding welding wire 9 set on the feeder 8 is drawn out by the feed roller 10 and fed to the torch 12 at the tip thereof through the conduit liner included in the conduit cable 11. Then, bead-on-plate welding is performed between the current-carrying tip and the steel plate 14. The conduit cable 11 was 6 m long and provided with a bent portion 13 formed with two 100 mmφ loops in order to give a feeding resistance to the wire. The feeder is provided with a detector for the peripheral speed Vr (= set wire speed) of the feed roller and an actual wire speed (Vw) detector 15 for the wire. The slip ratio S1 of the feedability evaluation index is S1 = (Vr−Vw) / Vr × 100%
It is represented by Further, a reaction force received by the wire from the liner during feeding by the load cell 16 provided in the feeding roller portion was detected as a feeding resistance R. When the feeding resistance R is 6 kgf or less and the slip ratio S1 is 10% or less, it is determined that the feeding property is good.

The feedability test was carried out under the condition of welding time = 3 minutes / 1, the feed resistance R and the slip ratio S1 were measured, and the average value was obtained. In the feedability test, place the test wire in a room at a temperature of 50 ° C.
The test was left for a month and then left in a room at a temperature of 5 ° C. or lower for 12 hours, and then a test was performed in the room at a temperature of 5 ° C. or lower (all test temperatures of the comparative examples were 5 ° C.). Table 2 shows the welding conditions. Table 3 shows the survey results. Examples 1 to 10 are examples of the present invention, and Examples 11 to 19 are comparative examples.

[0034]

[Table 2]

In Examples 1 to 10 of the present invention, the lubricating oil supplied has a pour point of ≤5 ° C. and an iodine value of ≤40 within an appropriate range. Excellent,
Even after being left in a severe temperature range for a long time, the feed resistance and the slip ratio were both low, showing good feedability, and the arc was stable. In Examples 11, 12, and 14, since the pour point of the lubricating oil fed was> 5 ° C., the feeding property was inferior. In Example 13, since the iodine value is> 40,
Oxidation of the lubricating oil proceeded in a high-temperature region (50 ° C.) and the pour point was raised, resulting in poor feedability.

In Example 15, the content of the synthetic ester oil contained in the feed lubricating oil was less than 50%, and as a result, the feedability was poor. In Examples 16 to 19, the type of the feed lubricant (solid lubricant + lubricating oil) is appropriate, but the amount of adhesion is too small or too large.
6, 18), the feeding resistance is high and the transmission is excessive (Example 1).
7, 19), the slip rate was high and the feedability was poor.

[0037]

[Table 3]

[0038]

According to the present invention, by applying a specific feed lubricant (solid lubricant + lubricating oil) to the wire surface, the feed resistance is increased due to the bending of the liner and the like, so that it can be used in a severe operating environment. In addition, it is possible to provide a welding wire capable of exhibiting good feedability even in a wide temperature environment from a low temperature to a high temperature, and a method for manufacturing the same.

[Brief description of the drawings]

FIG. 1 is a schematic view of a production line according to the present invention.

FIG. 2 is a diagram showing the procedure for conducting a feeding test.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Test wire strand 2 Dry hole die 3 CRD roller unit 5 Wet wire drawing machine 6 Finishing die 7 Product wire 8 Feeder 10 Feeding roller 11 Conduit cable 12 Torch 13 Bent part of conduit cable Patent applicant Nippon Welding Industrial Co., Ltd. and one other agent
Patent Attorney Shiina Jiang

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C10M 103: 06 103: 02 107: 38 105: 32) C10N 40:32 (72) Inventor Tohru Ono Tokyo 3-5-4 Tsukiji, Chuo-ku Nippon Steel Welding Industry Co., Ltd. 2784 Daikami, Hiratsuka-shi Japan Parka Rising Co., Ltd. Integrated Technology Laboratory (72) Inventor Tatsuro Mibe 2784 Ogami, Hiratsuka-shi, Kanagawa Japan Parker Rising Co., Ltd. Tokyo Division F-term (reference) 4E084 AA44 CA38 4E096 EA02 EA13 GA03 JA01 JA06 JA12 4H104 AA04A AA19A BB34A CD02A EA04A EA22A FA06 PA37 QA11

Claims (5)

[Claims] 1. A welding wire comprising a feed solid lubricant and a feed lubricating oil having a pour point of 5 ° C. or less and an iodine value of 40 or less. 2. The feed lubricating oil comprises one or more alcohol parts selected from neopentyl glycol, trimethylolpropane, and pentaerythritol, and has 12 to 1 carbon atoms.
The welding wire according to claim 1 or 2, wherein the synthetic ester oil having a neopentyl polyol ester structure comprising a fatty acid part containing 50 wt% or more of the saturated fatty acid of No. 4 is 50 wt% or more based on the total amount of the lubricating oil fed. 3. The solid lubricant to be fed is one or more of MoS ₂ , WS ₂ , polytetrafluoroethylene, and graphite.
The welding wire according to any one of claims 1 to 3, comprising at least one kind. 4. The amount of the solid lubricant fed is 10 k of wire.
2. The amount of the lubricating oil fed is from 0.1 to 1.5 g per 10 kg of the wire.
A welding wire according to any one of claims 1 to 4. 5. Dry drawing with a solid lubricant fed,
A method for producing a welding wire, wherein the wire is finished to a predetermined diameter by performing wet drawing using a lubricating oil having a pour point of 5 ° C. or less and an iodine value of 40 or less at least in a final die.