A former sand, constitute the main body of the original sand-coated sand, sand the original requirements are: high refractoriness coated sand, less volatile matter, high strength particles themselves, usually made from natural silica sand, mainly because of its rich reserves, cheap, to meet the casting requirements. Only the special requirements of the casting was made of special sand (such as zircon sand, chromite, ceramic sand, magnetic iron ore, etc.) as the original sand coated sand: General requirements for silica sand is: A.SiO2: cast iron and non-ferrous casting requires more than 90% sand coated sand reclamation line price, castings require more than 98%. B. acidic than alkaline sand sand. C. clay content <0.3%. D. Particle size distribution: 3 screen should adopt centralized, 5 sieve dispersion. E. grain shape: round good choice as silica sand, angular coefficient should generally be less than 1.3. Usually by two sand scrub to meet the requirements, but in order to improve the performance of coated sand, silica sand can be pickled or active treatment temperature (900-1200 ℃ roasting). Other special requirements for coated sand to meet the needs of different products, developed a series of special coated sand as: centrifugal casting coated sand, chilling coated sand, wet coated sand, sand sticking, anti-veined, Anti-cellulite coated sand. While in 2004 the newly introduced fast-curing coated sand on the basis of the performance has the cure rate can increase 30-70% coated sand regeneration, improve production efficiency and energy conservation easy collapsibility coated sand with good class strength, but also has excellent low temperature performance collapsing, for the production of non-ferrous castings. Coated sand (coated sand). I.e. before molding sand surface covered with a layer of solid resin film molding sand or core sand. There are two methods of cold and hot coating process: Cold method using ethanol dissolving the resin-coated sand renewable supply line, and join in the sand methenamine process, so that the two coated sand surface, ethanol volatile Qingdao coated sand regeneration line, was coated sand; calorimetry preheating the sand to a certain temperature, adding the resin to melt, stirring the resin coated sand surface, adding an aqueous solution of hexamine and lubricants, cooling, crushing, Screening was coated sand. For steel, cast iron coated sand reclamation line price, coated sand regeneration, provided by Qingdao Qingdao Heng Heng Machinery Co. Qingdao Heng Machinery Co., Ltd. (www.thjidian.com) strong, credible, Shandong Qingdao Cleaning equipment industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Qingdao Heng and you hand into the brilliant, for a better future!