Causes and occurrence: graphite is formed at high temperatures. Is the most widely distributed metamorphic graphite deposit, rich in organic matter by the Department or carbonaceous sedimentary rocks formed by regional metamorphism China: Lacey City, Shandong Province, one of China's important producer of graphite, graphite proved reserves of 6,871,100 tons of graphite milk, cash reserves of 6,399,300 tons. Another one is the graphite origin Panshi, graphite reserves of 5 million tons. World: Famous Origin: New York Ticonderoga graphite milk prices, high carbon graphite Madagascar and Ceylon, China's Heilongjiang Jixi Liu Mao was the largest producer. Pure charge subcooling large, is not conducive to the nucleation of graphite precipitation, less float. The main measures should be controlled to prevent the carbon equivalent according to the casting wall thickness; when small pieces of the wall thickness of not more than 30mm, appear critical carbon graphite floating equivalent of 4.7% - 4.9%; when the wall thickness of 30 to 100mm, appear critical carbon graphite floating equivalent of 4.5% - 4.6%; float appeared critical graphite carbon equivalent of 4.4% ~ 4.5% when the large wall thickness greater than 100mm. In particular, to control the carbon is less than 4. O%; the appropriate use of scrap, pig iron and silicon lower back with the use of charge; controlling the residual amount of rare earth is not too high; pouring temperature control; large cross section castings may be appropriate to add molybdenum or partial placement also prevents cold iron graphite float (see carbon equivalent cast iron, ductile iron). Roughness graphite, carbon industry in the North Sea Dragon, graphite provided by Carbon Co., Ltd. Weifang North Sea Dragon. Carbon Co., Ltd. Weifang Sea Dragon (www.longmentanye.com) Shandong Weifang, graphite and carbon products leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. In the North Sea Dragon carbon industry leadership with the staff warmly welcome all inquiries negotiations to create the North Sea Dragon carbon industry a better future.