來源：http://www.mallhometrade.com 發布時間：2021-12-02 15:50:28
Aluminum sheet is widely used in various industries because of its low density, high strength, high thermal conductivity, strong corrosion resistance and good physical and mechanical properties. Because the choice of welding method is not suitable for aluminum plate manufacturers, the deformation of aluminum alloy plate seriously affects the quality and performance of products. The following is a brief introduction to the alloy aluminum plate welding method.
1. Preparation prior to welding strictly clean the surface oxide film on both sides of the Weld Groove by chemical or mechanical means. Chemical cleaning is to clean the surface of the work piece with Alkali or acid. This method can remove not only the oxide film, but also the oil stain. The process is as follows: 6% ~ 10% sodium hydroxide solution by volume, soaking at 70 °C for 0.5 minutes → washing → neutralization by soaking at room temperature with 15% nitric acid for 1 minute → washing → warm washing → drying. The surface of the cleaned aluminum alloy is dark silvery white. Mechanical cleaning can use pneumatic or electric milling cutter, scraper, file and other tools. For thin oxide film, the oxide film can also be removed by polishing with a 0.25 mm copper wire brush.
2. Determine Assembly clearance and spot weld spacing. In the process of welding, the heat expansion of the alloy aluminum plate results in the reduction of the weld groove clearance. If the assembly clearance before welding is too small, the groove of the two plates will overlap during the welding process increase. After welding surface roughness and deformation; on the contrary, if the assembly gap is too large, it will be difficult to weld, may burn through. Proper spot welding spacing can ensure the required spot welding clearance, so it is an effective measure for aluminum plate manufacturers to choose proper assembly clearance and spot welding distance to reduce deformation. According to experience, the reasonable assembly process parameters of butt joints with different thickness are shown in table 2.
3. There are many kinds of welding products on the market at present. AC TUNGSTEN INERT GAS (Tig) welding should be used in general. It utilizes the electricity generated by the tungsten electrode and the workpiece under the protection of Argon Gas. The invention relates to a welding method for arc melting base metal and welding wire. When the welding machine works, due to the periodic change of the polarity of AC current, each cycle half-wave is DC positive connection. Half-wave is DC reverse connection. During the forward half-wave, the tungsten electrode can emit enough electrons without overheating, which is beneficial to the stability of the ARC. In the reverse half-wave process, the surface of the workpiece is generated. The oxide film can be easily removed and the weld with bright and beautiful surface can be obtained.
4. Selective wire. General selection of 301 pure aluminum wire and 311 aluminum-silicon wire.
一般采用左焊方式，焊槍與工件成60°角。當焊接厚度大于15毫米時，鋁板生產廠家采用正確的焊接方法，焊槍與工件成90°角。當焊接壁厚大于3毫米時，開V形坡口，夾角為60° ~ 70°，間隙不應大于1毫米，當壁厚小于1.5毫米時，不留坡口或間隙。
5. Selection of welding method and parameters. Generally, the left welding method is adopted, and the welding torch is at 60 ° angle with the workpiece. When the welding thickness is more than 15 mm, the aluminum plate manufacturer adopts the correct welding method, the welding torch and the workpiece at 90 ° angle. When the thickness of the welding wall is more than 3 mm, open the V-groove, the included angle is 60 ° ~ 70 ° , the gap should not be more than 1 mm, when the thickness of the wall is less than 1.5 mm, leave no groove or gap.