JP2010274273A - Sputter adhesion prevention agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sputter adhesion prevention agent capable of easily removing a dry coating film thereof after welding by only washing away it with water while maintaining good sputter adhesion prevention effect in high temperature environment during welding. <P>SOLUTION: The sputter adhesion prevention agent is mainly composed of water and is a paraffin-based, isoparaffin-based, naphthene-based, and aromatic-based hydrocarbon. The sputter adhesion prevention agent is prepared by emulsifying with a nonionic surfactant a hydrocarbon oil obtained from each one of liquids or by mixing plural kinds of the fluids which have a boiling point of 200-350°C and are a liquid at room temperature. The sputter adhesion prevention agent contains 1-20 mass% of the hydrocarbon oil per whole mass in a whole amount. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spatter adhesion preventing agent for preventing spatter generated when arc welding a metal material from adhering to the periphery of a welded portion, and more particularly to a spatter adhesion preventing agent used by being applied to a metal to be welded.

  When arc welding a metal material, spatter made of molten slag and molten metal may be generated in a granular form and scattered around the welded portion. When the generated spatter adheres around the welded portion, the appearance of the welded portion deteriorates. Moreover, when spatter adheres to the inside of a screw hole or the like, there is a possibility that the normal function as a product is impaired.

  Thus, in order to prevent spatter generated when arc welding a metal material from adhering to the periphery of the welded portion, a spatter adhesion preventing agent is used. Spatter adhesion preventing agents are roughly classified into two types depending on the application and the material of the metal to be welded. In other words, after welding, the type that allows the spatter adhesion inhibitor to be applied on top of the coating while leaving the coating, and the coating removed by washing the coating with water, acid, alkali, or solvent. There are types that you can do. Generally, the former type is used when the metal to be welded is mild steel, high-strength steel, etc., and the latter type is used when the metal to be welded is stainless steel, aluminum, or the like, or plating treatment is required. Is used.

  Examples of the component of the spatter adhesion preventing agent include inorganic powders such as calcium carbonate, or organic substances such as a surfactant. These inorganic powders or organic substances are dispersed or dissolved in water or a solvent and used as a spatter adhesion preventing agent. And inorganic powders, organic substances, and the like form a thin film on the metal surface, thereby preventing high-temperature spatter generated during arc welding from directly attaching to the metal surface. Specifically, as inorganic powders, calcium carbonate, silicic acid and silicate, aluminum, magnesium carbonate, magnesium hydroxide, titanium oxide, silicon carbide, etc. are used. As organic substances, resins, surfactants, high Boiling glycols, water-soluble polymers, oils and fats are used.

  And the water and solvent which disperse | distribute or melt | dissolve inorganic powder or organic substance have the effect | action which makes uniform the thickness of the thin film formed on a metal surface while making it easy to apply | coat a spatter adhesion prevention agent with a brush or spray. In addition, since the spatter adhesion preventing agent is used in a high temperature environment during welding, a nonflammable solvent is suitable. Therefore, a nonflammable solvent having high drying property is used as the solvent.

  As the spatter adhesion preventing agent, for example, Patent Document 1 discloses a spatter adhesion preventing agent containing a nonionic surfactant, a water-soluble resin, and an anionic surfactant. Patent Document 2 discloses a water-soluble welded spatter adhesion preventing agent for preventing spatter adhesion on a torch nozzle and tip used for gas shield arc welding.

JP-A-61-37381 JP 63-93497 A

  However, the above-described prior art has the following problems. The spatter adhesion inhibitor applied to the periphery of the weld and the surface of the metal to be welded is removed by washing with water or the like in the state of a dried coating film after the welding operation is completed. The operation of removing the dried coating film after welding is always necessary when the metal to be welded is stainless steel, aluminum, or the like, or it is necessary to perform plating. At this time, in order not to lengthen the time required for the post-treatment after the welding operation, it is necessary to easily remove the dried coating film only by washing with water. Since the spatter adhesion preventing agent disclosed in Patent Document 1 contains a water-soluble resin, it is difficult to remove the dried coating film after welding by simply rinsing with water. A detergent or a cleaning agent such as acid or alkali is used. It is necessary to wash and remove, and the time required to remove the dried coating film becomes long.

  In addition, the weld spatter adhesion inhibitor disclosed in Patent Document 2 also needs to be removed by washing with a detergent or a detergent such as acid or alkali, as in Patent Document 1, It is not easy to remove by simply rinsing with water.

  The present invention has been made in view of such problems, and easily removes a dried coating film after welding with water while maintaining a good spatter adhesion preventing effect even in a high temperature environment during welding. An object of the present invention is to provide an anti-spattering agent that can be used.

  The spatter adhesion preventive agent according to the present invention is mainly composed of water, paraffinic, isoparaffinic, naphthenic and aromatic hydrocarbons having a boiling point of 200 to 350 ° C. and liquid at room temperature. Or a mixture of a plurality of types of hydrocarbon oils emulsified with a nonionic surfactant, characterized in that the hydrocarbon oil is contained in a total amount of 1 to 20% by mass per total mass. .

  Moreover, it is preferable that the above-mentioned spatter adhesion preventing agent contains 3 to 10% by mass of the nonionic surfactant per total mass.

  Furthermore, the nonionic surfactant described above preferably has an HLB value of 9 or more.

  The spatter adhesion preventive agent of the present invention is obtained by emulsifying, with a nonionic surfactant, a hydrocarbon oil obtained by mixing hydrocarbon oils containing water as a main component and having a proper boiling point range alone or in combination. It is manufactured by dissolving in water in a moderately hydrophilic state. Therefore, even in a high temperature environment at the time of welding, it is possible to maintain an appropriate wettability and maintain a good spatter adhesion preventing effect as long as the thin film on the metal surface is not lost by drying. Further, the hydrophilic spatter adhesion preventive agent can be easily removed simply by rinsing with water as a dry coating film after welding.

  Furthermore, since the boiling point and content of the hydrocarbon oil are in an appropriate range, the wettability of the spatter adhesion preventive agent is maintained in a range where the hydrocarbon oil does not stick to the metal surface and deteriorate the welding workability. It can be uniformly applied to the metal surface.

Hereinafter, embodiments of the present invention will be described in detail. In the spatter adhesion preventing agent of the present invention, the hydrocarbon oil to be contained is mainly composed of paraffinic, isoparaffinic, naphthenic and aromatic hydrocarbons represented by the chemical formula C _n H _{2n + 2} . Specifically, for example, a hydrocarbon mainly having 10 to 20 carbon atoms is used. Each of these hydrocarbon oils has a boiling point of 200 to 350 ° C. alone and is liquid at room temperature. In the present invention, these hydrocarbon oils alone or in a mixture of two or more are emulsified with a nonionic surfactant and then dissolved in water to produce a spatter adhesion preventing agent.

The inventors of the present application have conducted extensive experiments to solve the above-described problems of the conventional spatter adhesion inhibitor. Of the hydrocarbon oils mainly composed of paraffinic, isoparaffinic, naphthenic and aromatic hydrocarbons represented by the chemical formula C _n H _{2n + 2} , those having a boiling point of 200 to 350 ° C. are used alone or in combination of two or more. , And then emulsified with a nonionic surfactant and dissolved in water, the thin film on the metal surface will not dry out and be lost even in a high temperature environment during welding, maintaining moderate wettability. Thus, it has been found that the sputter adhesion inhibitor hydrophilized while maintaining good spatter adhesion suppression can be easily removed as a dry coating after welding by simply rinsing with water. And by setting the hydrocarbon oil content in an appropriate range, the wettability of the spatter adhesion inhibitor is maintained in a range where the hydrocarbon oil does not stick to the metal surface and deteriorate the welding workability. It was found that it can be uniformly applied to the metal surface.

  Hereinafter, the reason for the numerical limitation in the spatter adhesion inhibitor of the present invention will be described.

“Boiling point of hydrocarbon oil: 200 to 350 ° C.”
In the present invention, the hydrocarbon oil is the most important composition, and the boiling point of the hydrocarbon oil particularly affects the wettability of the thin film in a high temperature environment during welding. If the boiling point of hydrocarbon oil is low and it is easy to dry in a high temperature environment, the thin film formed on the metal surface is easily dried and evaporated due to the high temperature during welding. And it becomes impossible to maintain sputter adhesion suppression. On the other hand, if the boiling point of the hydrocarbon oil is too high, the coating film becomes sticky due to the large viscosity of the hydrocarbon oil, which tends to hinder the welding operation. In addition, for example, when the time for forming the dry coating is not sufficiently obtained after applying the liquid spatter adhesion inhibitor to the metal surface due to a short time given to the welding operation, etc. The spatter adhesion preventing agent is mixed in the molten metal, and the soundness of the weld metal tends to be lowered. Furthermore, when a spatter adhesion inhibitor is mixed in the weld groove, welding defects such as blow holes and cracks are likely to occur. In the present invention, when the boiling point of the hydrocarbon oil is less than 200 ° C., the thin film on the metal surface is easily dried at the time of welding, and the sputter adhesion inhibiting property is lowered. On the other hand, when the boiling point of the hydrocarbon oil exceeds 350 ° C., the workability of welding is lowered, the soundness of the weld metal is lowered, and welding defects are likely to occur. Therefore, the boiling point of the hydrocarbon oil of the present invention is defined as 200 to 350 ° C.

“Hydrocarbon oil content: 1 to 20% by mass per total mass”
In the present invention, the hydrocarbon oil maintains good spatter adhesion suppression and also affects the wettability of the spatter adhesion inhibitor. When the content of the hydrocarbon oil in the spatter adhesion inhibitor is small, it becomes impossible to maintain spatter adhesion suppression. On the contrary, if the content of hydrocarbon oil is large, hydrocarbon oil with a high boiling point will occupy a large proportion in the spatter adhesion preventive agent, the wettability on the metal surface will be high, and the welding workability is likely to deteriorate. Become. In addition, the soundness of the weld metal is likely to deteriorate, and welding defects such as blow holes and cracks are also likely to occur. In the present invention, when the content of the hydrocarbon oil is less than 1% by mass with respect to the total mass, it is not possible to obtain good sputter adhesion suppression. On the other hand, when the total amount of hydrocarbons exceeds 20% by mass per total mass, welding workability is lowered, the soundness of the weld metal is lowered, and welding defects are likely to occur. Therefore, the content of the hydrocarbon oil of the present invention is 1 to 20% by mass per total mass. The content of the hydrocarbon oil is preferably 5 to 15% by mass per total mass. The hydrocarbon oil is preferably mainly composed of hydrocarbons having 10 to 20 carbon atoms. When the carbon number of the hydrocarbon oil is less than 10, the thin film formed on the metal surface is lost by drying and evaporation due to the high temperature at the time of welding, and the sputter adhesion inhibiting property is likely to be lowered. On the other hand, when the number of carbon atoms of the hydrocarbon oil exceeds 20, when hydrocarbon oil components are mixed in the welding groove, they are not quickly decomposed even at high temperatures during welding or are difficult to evaporate. Welding defects occur, and the soundness of the weld metal is likely to deteriorate. Therefore, the hydrocarbon oil is preferably mainly composed of hydrocarbons having 10 to 20 carbon atoms.

“Content of nonionic surfactant: 3 to 10 mass% per total mass”
In the present invention, the surfactant used for emulsifying the hydrocarbon oil is a nonionic one, for example, polyoxyethylene alkyl ether, polyoxyethylene sorbitan alkyl ester or the like. The surfactant of the present invention is an emulsifier that stably disperses or dissolves itself in water, which is the main component of the spatter adhesion preventing agent, and also emulsifies hydrocarbon oil to stably disperse or dissolve in water. Works. In the spatter adhesion preventing agent of the present invention, the content of the nonionic surfactant is preferably 3 to 10% by mass per total mass. When the content of the nonionic surfactant is less than 3% by mass per total mass, the action of emulsifying the hydrocarbon oil and stably dispersing or dissolving it in water is reduced, and the hydrocarbon oil is on the oil film surface. Water and hydrocarbon oil are easily separated into two layers by repelling water. In addition, since the hydrophilicity of the coating film is reduced on the metal surface to be welded, the dry coating film after welding repels water, and the water washing removability is reduced. On the other hand, when the content of the nonionic surfactant exceeds 10% by mass, the surfactant occupies a large proportion in the spatter adhesion preventing agent in a state where the hydrocarbon oil is emulsified. The wettability becomes high and the welding workability tends to be lowered. In addition, the soundness of the weld metal is likely to deteriorate, and welding defects such as blow holes and cracks are also likely to occur. Accordingly, the content of the nonionic surfactant of the present invention is preferably 3 to 10% by mass based on the total mass.

“HLB value of nonionic surfactant: 9 or more”
As described above, the nonionic surfactant used for emulsifying the hydrocarbon oil is stably dispersed or dissolved in water, which is the main component of the spatter adhesion preventing agent, and emulsifies the hydrocarbon oil. It acts as an emulsifier that is stably dispersed or dissolved in water. In the present invention, the nonionic surfactant preferably has an HLB (Hydrophile-Lipophile Balance) value of 9 or more. If the HLB value of the nonionic surfactant is less than 9, the dispersion or solubility of the surfactant itself in water decreases, and after emulsifying the hydrocarbon oil, it becomes difficult to stabilize the dispersion or dissolution in water. . Therefore, it is preferable that the nonionic surfactant has an HLB value of 9 or more.

  In addition, a rust preventive agent, an antiseptic | preservative, etc. can be further added to the spatter adhesion preventive agent of this invention, and rust prevention property and antiseptic property can be improved.

  Next, arc welding using the spatter adhesion inhibitor of the present invention will be described. First, a liquid spatter adhesion preventing agent is applied around the site to be welded using a brush or the like. When the application of the spatter adhesion inhibitor is completed, it is dried by leaving it alone. At this time, the spatter adhesion preventing agent forms a dry coating film on the coated metal surface.

  Next, if a coated arc welding rod is used as an electrode in the case of coated arc welding and a tungsten electrode or a welding wire is used as an electrode in the case of gas shielded arc welding, a current is applied between the base metal and the electrode. Arc discharge occurs between the base material and the electrode. At this time, spatter made of molten slag and molten metal is generated in a granular form and scattered around the welded portion. In particular, when arc discharge is unstable, spatter is prominent. The generated spatter scatters around the weld and adheres to the dry coating film of the spatter adhesion inhibitor. Since the spatter adhesion preventive agent of the present invention has a boiling point of 200 to 350 ° C., which is regulated within an appropriate range of relatively high temperatures, it maintains a good dry coating film on the metal surface even in a high temperature environment during welding. However, the welding workability does not deteriorate due to the stickiness of the coating film.

  When the arc welding is completed, water is poured on the dry coating film to which the spatter has adhered, and the periphery of the welded portion is washed with water. The spatter adhesion preventive agent of the present invention is produced by dissolving hydrocarbon oil in water in a state of being appropriately hydrophilized by emulsifying with a nonionic surfactant. And the content of the hydrocarbon in the spatter adhesion preventing agent is regulated within an appropriate range. Therefore, the hydrophilic spatter adhesion inhibitor can be easily removed by simply rinsing with water as a dry coating after welding.

  Hereinafter, examples showing the effects of the spatter adhesion inhibitor of the present invention will be specifically described in comparison with comparative examples.

  Various hydrocarbon oils shown in Table 1 were mixed alone or mixed and emulsified with a nonionic surfactant, and dissolved in water to prepare flux adhesion inhibitors of Examples and Comparative Examples having various components. . Table 1 shows the main components and boiling points of each hydrocarbon oil used. In addition, as a nonionic surfactant, polyoxyethylene alkyl ether (manufactured by Nippon Shokubai Co., Ltd., product name: Softanol 70 (HLB value 12.1), Softanol 50 (HLB value 10.0) or Softanol 30 (HLB value 8) 0.0)) and a nitrogen halide sulfur compound as the preservative. These addition amounts are shown in Tables 2 and 3. In addition, Tables 2 and 3 show the compositions of the produced anti-spattering inhibitors of Examples and Comparative Examples.

  After applying the spatter adhesion preventing agents of Examples and Comparative Examples having the compositions shown in Tables 2 and 3 to the base material with a brush and leaving to stand for 3 hours to form a dry coating film, a flux-cored wire was used. MIG welding was performed. As a base material to be welded, two SS400 steel plates defined in JIS G 3101 having a width of 150 mm, a length of 300 mm, and a thickness of 10 mm are used, and placed on a horizontal plane so that the thickness direction is vertical. The other steel plate was erected at the center of the steel plate so that the thickness direction was horizontal, and both sides of the fillet portion were MIG welded. As the flux-cored wire, the flux-cored wire for Cr-Mo steel mag welding shown in Table 4 by Kobe Steel was used.

  About the spatter adhesion prevention agent of each Example and the comparative example, the uniformity of the coating film when apply | coating to a base material with a brush was determined visually. And the thing with favorable uniformity of the coating film was evaluated as ◎, and the film with slight unevenness was determined as ◯.

  Moreover, while checking the sputter adhesion inhibitory property by visually confirming the state of the metal surface after MIG welding, the presence or absence of welding defects such as blow holes and cracks was also confirmed. And, it was determined that the spatter adhesion suppression was good, A, the spatter adhesion suppression slightly decreased but no problem was found even if it was used, and the bad one was not good. Regarding weld defects, ◎ indicates that there were no weld defects, ○ indicates that some weld defects occurred but did not reduce the joint strength, and X indicates that joint strength decreased due to the occurrence of weld defects. did.

  Furthermore, water is poured on the dried coating film after welding, and the hydrophilicity of the coating film is judged by visually confirming that there is no water repellency on the coating film. Removability was determined. Then, the case where the hydrophilicity was good was judged as ◎, the case where the hydrophilicity was slightly lowered but not enough to reduce the water-removability was judged as ◯, and the case where the hydrophilicity was not good was judged as x. In addition, ◎ that the dry paint film could be easily removed by simply rinsing with water, ◯ that the dry paint film was removed by just rubbing lightly, although some dry paint remained slightly by rinsing with water. Those that could not be removed without using the remaining cleaning agent were judged as x.

  Tables 3 and 4 show the results of determination of coating film uniformity, sputter adhesion suppression, presence / absence of welding defects, hydrophilicity, and water rinsing removability in each example and comparative example.

  As shown in Tables 2 and 3, Example No. Nos. 1 to 10 are comparative examples in which the boiling point of the hydrocarbon oil in the spatter adhesion inhibitor satisfies the scope of the present invention and does not satisfy the scope of the present invention. Compared with Comparative Example No. 3, the weld defect suppression property is excellent. Compared with 4, the sputter adhesion suppression is superior.

  Comparative Example No. 1 is different from Examples 1 to 10 in which the boiling point range of the hydrocarbon oil satisfies the range of the present invention, but the hydrocarbon oil content is small and the hydrocarbon oil content satisfies the range of the present invention. Thus, the water-removability, hydrophilicity and spatter adhesion inhibiting property of the coating film were inferior. On the other hand, Comparative Example No. In No. 2, the hydrocarbon oil content was excessive, the soundness of the weld metal was lowered, and welding defects were generated.

  Example No. which satisfies the scope of the present invention. Among 1 to 10, in Examples 1 and 3 to 8, the content of the nonionic surfactant satisfies the scope of claim 2 of the present invention, and the content of the nonionic surfactant is claimed. Compared with Example 10 in which the water-washing removability and hydrophilicity of the coating film are superior to those of Example 9 below the range of Item 2, and the content of the nonionic surfactant exceeds the range of Claim 2. Excellent weld defect suppression.

  In Example 2, the content of the nonionic surfactant satisfies the range of claim 2 of the present invention, but the HLB value of the nonionic surfactant is less than the range of claim 3. Therefore, in Example 2, the hydrophilicity of the coating film was lowered as compared with Examples 1 and 3 to 8 in which the HLB value of the nonionic surfactant satisfied the range of claim 3.

Claims (3)

Water as the main component,
Non-ionic hydrocarbon oils obtained by mixing paraffinic, isoparaffinic, naphthenic and aromatic hydrocarbons having a boiling point of 200 to 350 ° C. at room temperature alone or in combination. Emulsified with a surfactant,
A spatter adhesion preventing agent comprising 1 to 20% by mass of the hydrocarbon oil in a total amount per total mass. The spatter adhesion preventive agent according to claim 1, wherein the nonionic surfactant is contained in an amount of 3 to 10% by mass based on the total mass.   The spatter adhesion preventive agent according to claim 1 or 2, wherein the nonionic surfactant has an HLB value of 9 or more.