In order to prevent the oxide film formed in the cast, we need to let the metal, especially in milli turbulent state into the mold cavity. For most castings, the use of gravity casting method it is impossible to do this, because the sprue head height will speed up the flow rate which occurred in Hebei turbulence dross recovery, so be sure to use anti-gravity method or level Die casting technology. Such filters slow down the speed of the metal flow to slow enough to prevent oxide production. Also to be injected into the mold cavity from the bottom, each level of the order of injection casting electricity should be carefully designed to avoid "waterfall" - die falling liquid metal from a higher level to a lower level, so that Freshmen metal oxide surface. Use of injection mold from the bottom of the method, liquid metal oxide layer on top of the sand will be promoted to the top level of the box and into the top riser, so it will not damage the castings. Welding difficulty (1) easily oxidized. In the air, the aluminum oxide combined with easy to produce a dense aluminum oxide film (thickness of about 0.1-0.2μm), high melting point (about 2050 ℃), far more than the melting point of aluminum and aluminum alloys (about 600 ℃ or so). Alumina density 3.95-4.10g / cm3, aluminum is approximately 1.4 times the surface of the aluminum oxide film of easy absorption of moisture Henan dross recycling, welding, it prevents fusion of the base metal, easy to form pores , slag, incomplete fusion and other defects, performance degradation caused by welding. (2) easy to produce pores. The main reason porosity of aluminum and aluminum welding is hydrogen, since large amounts of hydrogen soluble liquid aluminum, and solid aluminum hardly dissolved hydrogen, so when bath temperature rapid cooling and solidification dross recycling, hydrogen too late to escape, easily aggregated to form pores in the weld. Hydrogen is difficult to completely avoid the holes, many sources of hydrogen, electric arc atmosphere of hydrogen, aluminum, wire surface oxide film adsorbed moisture in the air and so on. Practice has proved that, even if the argon gas by GB / T4842 standards, purity of 99.99%, but when the moisture content of 20ppm, there will be a lot of dense pores, when the relative humidity exceeds 80%, if not take heat and other measures, the weld will obviously appear pores. At the same time, low current welding Hunan dross slow recovery, increase weld cooling time, and use wire arcs puddle agitation, can better help the gas discharge bath. Shengxin scrap metal recycling (Figure) | Hebei dross recovery | dross Recycling scrap metal from the Linyi City Shengxin Limited. Linyi City Shengxin scrap metal recycling Ltd. (shengxin.tz1288.com) located in Linyi Economic Development Zone, Shandong Mei Buzhen. Scraps and development in the wave of market economy, the current Shengxin scrap metal recycling has a high profile in the scrap metal, and enjoys a good reputation. Shengxin scrap metal recycling business alliance has made the entire network certification, marking our service and management level has reached a new height. Shengxin scrap metal recycling all employees willing to work with all people of insight and common development, for a better future.