Coated sand will review the index in 1992 amended the provisions of coated sand industry standards are: room temperature flexural strength, thermal bending strength, loss on ignition, particle size and melting point. Optional detection indicators are: room temperature tensile strength, tensile strength hot, gas evolution and mobility. Performance coated sand for nearly 10 years has been greatly improved, a corresponding increase in the number of new detection indicators: (1) high temperature compressive strength - to simulate actual conditions of casting, coated sand core test at the time of 1000-1500 ℃ compressive strength. (2) Heat time - test coated sand core at a high temperature (700-1500 ℃) to maintain strength, no distortion, no collapsing of time. (3) anti-Shelling - The test coated sand against shelling capacity. Coated sand coated sand production method, mixed anatomy experienced a dry blend method, cold coating method, temperature coating method, a thermal coating method four stages, the current production of coated sand almost all thermal coating method. Thermal coating process is the first raw sand heated to a certain temperature, then the resin respectively, Wuluo off product solution and calcium stearate are mixed and stirred, cooled from crushing and screening. Due to differences in formulation, mixing system technology is different. Currently domestic species coated sand production line a lot, manual feeding of semi-automatic production line is about 2000 to 2300, coated sand, computer-controlled automatic production lines also has nearly 50, to effectively improve production efficiency and product stability. Century has come, this is a modern high-tech rapid development and product quality, environmental protection era of fierce competition. People for the requirements of their own living environment of increasingly high, companies should be in accordance with the requirements of environmental laws to organize production. Machinery industry, the foundry industry is a serious pollution, energy consumption, and poor working conditions in the industry. 21st century styling, core technical progress key issues should be developed pollution, less pollution, low production cost, energy-saving materials and labor conditions are good modeling, core processes. Thus, coated sand technology future development direction should be: (1) reducing environmental pollution coated sand, coated sand recycling equipment, the development of low free phenol, low gas, less pollution phenolic resin, the protection of human survival natural environment. (2) Phenolic resin substitutes. Because phenolic resins are expensive to develop a new type of cheap binder is a priority. (3) further research and improvement rheology phenolic resin coated sand equipment, and constantly improve the reaction of the resin, coating and curing properties. (4) The performance resin synthesis process control, production of coated sand, resin macromolecules and small molecules suitable grading also need further research to improve the toughness and resistance to shelling resin. (5) Further study of the old sand reuse. With the increasing amount of coated sand, many manufacturers have reached several thousand tons more than the amount of research coated sand used sand reclamation and reuse has been of great practical significance, not only can improve the performance of coated sand, and but also save costs, reduce waste materials on the environment pollution-coated sand | Qingdao Heng | coated sand regeneration equipment from Qingdao Heng Machinery Co. Coated Sand | Qingdao Heng | coated sand recycling equipment Qingdao Heng Machinery Co., Ltd. (www.thjidian.com) this year introduced a new upgrade, the above picture is for reference only, please call the contact picture on this page or telephone obtain the latest information, contact: Liu promotion.