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The rapid development of large-scale coal chemical industry needs corresponding technical and equipment support, especially coal to oil, methanol, synthetic ammonia, and coal to olefin coal chemical industry needs a large number of large-scale coal chemical valve equipment. Among them, coal to oil (coal liquefaction method of oil), is a key development of a new technology, coal direct liquefaction device process conditions are very harsh, the valve put forward very high requirements. Coal-to-oil is characterized by inflammability, high temperature, corrosion and wear, etc., and the corresponding requirements for valves will be high.