The Pengfeiqin and Yongan coal mines were built in 1954 and have a mining history of more than 60 years. Because of the long mining age, the remaining recoverable reserves of 3# coal are only 3.7 million tons, and they were once plagued by resource depletion.

　　Since the beginning of this year, on the basis of innovative re-mining methods and based on the underground working face geology and coal seam storage conditions, the mine has proposed to merge the original 3103 working face and 3104 working face to form a new subject of 226-meter extended fully-mechanized caving face .

　　The fully mechanized caving face was originally designed as two working faces with lengths of 110 and 86 meters, respectively, with a 30-meter section of coal pillars in the middle. The innovative design technology now combines the two working faces into one. The reserve is about 1.137 million tons, the length of the working face reaches 226 meters, and the W type ventilation is adopted. 3103 fully mechanized caving face is a modern working face that integrates top coal support and high-power mining equipment.

　　　It is understood that the implementation of the project of lengthening the working face can reduce the roadway excavation and save the cost of excavation; reduce the number of moving; save the preparation time of the mining roadway, greatly alleviate the current situation of coal mining connection; improve production efficiency and reduce production costs; increase single-sided mining Reserves, extend the service life; increase the reserves of coal pillars recovered in three sections. Calculated with a coal pillar width of 30m, an extra 533,600 tons of coal pillars in three sections can be recovered. 107 million yuan. The net investment benefit of the project is about 100 million yuan.

　　It is expected that the long working face will be installed and tested by the end of December this year.