Mixing method of film-coated sand
After the four stages of dry mixing method, cold film covering method, warm film mulching method and hot film covering method, at present, the production of film covering sand is almost all using hot film covering method.
Thermal film mulching process is to heat the original sand to a certain temperature, and then mixed with resin, Ulol aqueous solution and calcium stearate, after cooling and crushing and screening.Due to the differences in the formula, the mixing process is different.
At present, there are many kinds of coated sand production lines in China. There are about 2000~2300 semi-automatic production lines with manual feeding, and nearly 50 automatic production lines controlled by computer, which effectively improves the production efficiency and product stability.
Since 1977, due to the vigorous development of China's machinery, electronics, light industry, instrument, transportation and other industrial departments, the demand for casting mold is more and more in quantity, the quality requirement is getting higher and higher, and the supply period is getting shorter and shorter.
High production efficiency: high machine productivity, such as domestic J 3 horizontal cold air die cast aluminum 600~700 times every eight hours; die cast aluminum life, one die cast aluminum, die cast aluminum clock alloy, life can reach hundreds of thousands of times, even millions of times; easy to realize mechanization and automation.