Adhesive properties have a great impact on the quality of coated sand, people have been working on how to improve the performance of phenolic resin, and find alternatives to phenolic resin. Abroad has developed a special resin with different properties, such as high strength, low gas resin, the resin is easy to collapsing, there are reports of the use of modified polyester resin, but did not get the full extension, so far is still widely used modified phenolic resin. China in recent years in research and development dedicated phenolic resin coated sand faster, has developed a different use for the production of modified phenolic resin based coating wet sand by hand: the coated sand wet compressive strength can be 0.1-0.3 be adjusted within MPa. Stored for more than three months, or the system is suitable for hand molding core (like tung oil sands Hop fat sand) coated sand regeneration, at room temperature, coated sand regeneration after stripping vendors will type (core) or bake oven furnace heating, the heating temperature 250-350 ℃, heating time 3-10min, type (core) after curing with high intensity, low-fat volume, a small amount of creep-shaped, non-hygroscopic characteristics. The coated sand suitable for single pieces and small batch production of high precision casting, particularly suitable for township enterprises to adopt. It is worth noting that when the type (core) heat cured coated sand regeneration manufacturers, must wait to reach the desired temperature furnace heating can be placed Shandong coated sand regeneration, avoid raw sand with a heating furnace to heat up, the original sand is mainly composed of 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 casting Claim. 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 require more than 90% sand, 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). Qingdao coated sand coated sand regeneration regeneration _ _ provided by Qingdao Qingdao Heng Heng Machinery Co., Ltd. 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!