JPH0453633B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of Industrial Application) The present invention relates to a welding spatter adhesion prevention agent that is applied to a welding nozzle during arc welding of metal parts to prevent the adhesion of welding spatters and to perform stable welding. (Prior Art) Conventionally, paste, grease, or liquid oil has been applied to welding nozzles or welded metal parts to form a film to prevent welding spatter from adhering to the nozzles or metal parts. Ta. The components of these oils include mineral oil, fatty oil, synthetic oil, etc. as the base oil, and organic film-forming agents such as fatty acids and metal soaps, as well as inorganic substances such as graphite, molybdenum disulfide, zirconium oxide, and aluminum oxide. Materials containing anti-welding agents and the like were used. (Problems to be Solved by the Invention) Among the conventionally used oils, those in the form of paste, grease, or high viscosity liquid tend to adhere in excess, making it difficult to remove and reapply. It becomes difficult to do. Anti-welding agents are added to supplement the oxidation and heat resistance of the base oil and film-forming agent, but graphite and molybdenum disulfide are easily oxidized at high temperatures and decompose and lose their effectiveness at 400°C. . Zirconium oxide and aluminum oxide are stable at 800-1500℃.
This point is good, but the former has a specific gravity of 5.6 to 5.89, and the latter has a specific gravity of 5.6 to 5.89.
3.99, it is easy to separate even if it is added to the oil and dispersed, and it is difficult to make it exist uniformly in the coating film, resulting in poor adhesion prevention effect. Therefore, these conventional oils have the problem that they are not suitable for the purpose of high-efficiency welding, which is recently required to increase the number of welds to be welded between once application and re-application as much as possible. (Means for Solving the Problems) In order to achieve such high efficiency welding, the present invention fundamentally reconsiders the composition of conventional oil agents and pursues an ideal composition. The compositional features of the present invention are as follows, which are the main points of the means for solving the problems. 1 The oil agent is an emulsion-type water-soluble oil agent, and a thin viscosity emulsion is applied to the nozzle to evaporate water and leave a uniform thin oil film to avoid excessive adhesion. 2. Oxidation resistance was improved by using oxidation-resistant synthetic oil, especially ester-based synthetic oil, together with mineral oil as the base oil. 3. Wax, especially a high melting point, hard wax, was used as a film forming agent to provide an excellent spatter adhesion prevention effect even with a thin film, and to improve oxidation resistance. 4. Various anti-adhesive agents were investigated, including the aforementioned graphite, molybdenum disulfide, and zirconium oxide, but the best results were obtained with boron nitride. This is boron nitride at 1000-1050℃
It is stable up to temperatures, has very good heat resistance, has little wetting property with metals, and has a low specific gravity.
Molybdenum disulfide, zirconium oxide, in 2.23
It is significantly smaller than aluminum oxide, is stable at high temperatures, is difficult to weld to metals, and is easily dispersed evenly in oils and coatings, and is known as a solid lubricant. This is thought to be due to the fact that it has lubricity, which is advantageous in removing adhering spatter. As a result of our research, the present inventors discovered for the first time that boron nitride has unique properties not found in other anti-welding agents and is extremely suitable as an anti-welding agent. This is the basis of the invention. Therefore, the present invention provides a welding spatter adhesion prevention agent that is applied to a welding nozzle to prevent welding spatters from adhering to the welding nozzle, which contains 30 to 78.9% by weight of base oil, 0.1 to 10% by weight of wax, 1 to 30% by weight of boron nitride powder, and a surfactant. 20
It is a welding spatter adhesion prevention agent characterized by containing ~30% by weight, and it is diluted with water at the time of use.
It is applied to the nozzle as a ~60% by weight emulsion. (Function) The base oil is the main component of the film after the water in the oil emulsion applied to the nozzle evaporates, and it is easy to flow and has the effect of uniformly covering the oil.It is a synthetic oil and a mineral oil.Mineral oils include JISK2238 machine oil,
Synthetic oils such as JISK2213 turbine oil include ester-based synthetic oils such as n-butyl stearate and 2-ethylhexyl palmitate, diester-based synthetic oils such as di,2-ethylhexyl sebacate, and diisooctyl adipate, and polypropylene glycol monomethyl ether. Silicone-based synthetic oils such as polyalkylene glycol-based synthetic oils and polymethylphenylsiloxane can be used, but ester-based synthetic oils have excellent oxidation resistance, so they are used alone or as a mixture with mineral oil. It is necessary. The mixing ratio of synthetic oil and mineral oil is 10:90 (weight ratio)
It is preferable to use more synthetic oil. Wax increases the heat resistance and mechanical strength of the coating, and also functions to disperse boron nitride into the base oil. Waxes, natural waxes such as montan wax, and synthetic waxes such as stearamide, N,N'-ethylenebisstearamide, polyethylene wax, polyurethane wax, docosyl behenate, and tetracosyl lignocerate can be used. However, high melting point waxes with a melting point of 70°C or higher, particularly 100°C or higher are preferred. Boron nitride powder has the effect of protecting spatter from base oil and wax due to its heat resistance, and it must be in powder form and easily dispersed in base oil and wax. A range of values is preferred. The surfactant has the function of dispersing and emulsifying the base oil, wax, and boron nitride mixture in water, and also has the function of promoting uniform adhesion of the oil agent to the nozzle surface. polyoxyethylene nonyl phenyl ether,
A nonionic activator such as polyoxyethylene sorbitan oleate, an anionic activator such as sodium petroleum sulfonate, sodium sulfosuccinate, triethanolamine oleate, potassium oleate, etc. are used. The significance of limiting the content of each component above is that if the other components are below their respective lower limits relative to the base oil, they will not be effective.
If the wax exceeds the upper limit, the fluidity of the film will be poor and it will be difficult to form a uniform film, and if the boron nitride exceeds the upper limit, the film will become brittle. This is because when the amount of surfactant exceeds the upper limit, the adhesion of the oil film to the nozzle surface of the emulsion deteriorates, making it difficult to form a uniform film. Antioxidants and rust preventives can also be added as other ingredients. (Example) Each Example and Comparative Example having the composition shown in Table 1 was manufactured by blending each component and mixing them uniformly, and 50% by weight of each Elmagillon was recycled and used as a sample. Each sample was tested using the following test method, and the effects were compared and confirmed. Test method A: Small AC arc welding test (laboratory test) Ceramic welding nozzles are used in welding the arm joints of rear axle housings at automobile factories, so the test was conducted under the same conditions. Ceramic material (aluminum oxide) 50×50×
Each of the above samples was coated on one side of a 5 (mm) plate and dried for 1 hour in a constant temperature bath at 105°C to obtain a test piece. Then, the four test pieces were placed upright on a cast iron plate measuring 300 x 300 x 50 (mm) to form a square of 50 mm on each side, with the coated surfaces facing inward. Next, we used a small AC arc welding machine (Toyo Arc TK-150, secondary current 90/130A, no-load voltage 50V, usage rate 20%) manufactured by Toyo Transformer Co., Ltd. to place each test piece on the cast iron plate at the center of the square. Arc welding was performed at the points for 1 minute. After that, each test piece was cooled and washed with a 1:1 mixed solvent of ethyl alcohol and ethyl ether using an ultrasonic cleaner.After drying, the weight of each piece was measured, and the difference in weight before and after the test was calculated. The amount of adhering spatter (shown in Table 1) was determined, and the quality was determined based on the size. B. On-site test at an automobile factory A total of three types of welding spatter adhesion prevention agent were used on a 75mm rear axle bundling welding line at an automobile factory: the product of the present invention (Example 2), commercial product A, and conventionally used 90 turbine oil. The test oil was applied to a ceramic welding nozzle, and the amount of spatter deposited on the nozzle and the period from application until the adhesion prevention effect disappeared and reapplication was required for each sample oil were compared. As a result, the amount of spatter deposited on the product of the present invention is 1/3 that of commercial product A of 16 turbine oil.
A good result of ~1/4 was obtained. Therefore, it has been found that the product of the present invention has the effect of significantly extending the period of use until reapplication by 6 times that of 90 turbine oil and 3 to 4 times that of commercial product A. This means that by using the product of this invention, the operating rate of the welding line will be significantly improved.In particular, recent welding lines have adopted arc robots and are fully automated, and in the case of recoating, the entire line Considering the circumstances that require the discontinuation of welding, the fact that we were able to significantly extend the usage period and drastically reduce the number of reapplications is an extremely significant achievement in achieving the goal of increasing welding efficiency. becomes.

【table】

[Table] (Effects of the invention) When the anti-adhesion agent of the present invention, which is characterized by containing base oil, wax, boron nitride powder, and surfactant in a specific ratio, is applied to a welding nozzle, the results are shown in the test results column above. It was confirmed in the laboratory and in the field that the effect of preventing spatter adhesion was extremely excellent, and that the purpose of the invention could be achieved.

Claims (1)

[Claims] 1 In the welding spatter adhesion prevention agent applied to the welding nozzle to prevent the adhesion of welding spatters, base oil 30
~78.9% by weight, wax 0.1-10% by weight, boron nitride powder 1-30% by weight, surfactant 20-30% by weight
A welding spatter adhesion inhibitor characterized by containing.