The traditional simple wooden box packaging and transportation can't solve the disadvantages that these high-tech products can't be effectively protected and have poor mobility during long-distance transportation. In view of this disadvantage, a new alternative transportation packaging product-air box has emerged. The increasingly frequent international trade has entered a golden stage for the use and development of air boxes, especially in the fields of stage lighting equipment, medical instruments and equipment, audio-visual system multimedia, photoelectric industry, military transportation packaging and military equipment transportation and other high-tech equipment.
Second, welding technology for aluminum box of air box
(1) Welding wires are generally 31 pure aluminum welding wire and 311 aluminum-silicon welding wire.
(2) Selection of welding method and parameters
Generally, left welding method is used, and the welding torch and the workpiece form an angle of 6. When the welding thickness is more than 15mm, the welding torch and the workpiece form a 9-degree angle.
(3) Preparation before welding
Strictly clean the surface oxide film on both sides of the weld groove by chemical or mechanical methods.
pneumatic or electric milling cutter, scraper, file and other tools can be used for mechanical cleaning, and ．25mm copper wire brush can also be used to polish and remove the thin oxide film.
weld immediately after cleaning. If it is left for more than 4h, it should be cleaned again.
(4) Material characteristics of aluminum and aluminum alloy in aluminum box
Aluminum is a silvery light metal, which has good plasticity, high electrical and thermal conductivity, as well as oxidation resistance and corrosion resistance. Aluminum is easily oxidized to produce aluminum oxide film, and inclusions are easily produced in the weld, thus destroying the continuity and uniformity of metal and reducing its mechanical properties and corrosion resistance.
(5) Aluminum and aluminum alloy materials in aluminum boxes are difficult to weld
Aluminum alloy materials are easily oxidized. In air, aluminum is easily oxidized to form a dense aluminum oxide film (thickness is about .1-.2 μ m) with a high melting point (about 25℃), far exceeding the melting points of aluminum and aluminum alloys (about 6℃). The density of alumina is 3.95-4.1 g/cm3, which is about 1.4 times that of aluminum. The surface of alumina film is easy to absorb moisture, which hinders the fusion of basic metals during welding, and it is easy to form defects such as porosity, slag inclusion and incomplete fusion, which leads to the decline of weld performance.