subject: Mining Equipments Manufacturer In China Sbm Provide Mobile Coal Crushers For Underground Mining. [print this page] A deep coal seam is accessed by an opening to the surface called a portal. The portal opening are called drift, slope, or shaft mines. Drift mines cut down the coal bed from the outcrop, slope mines cut through overburden rock at an angle to get to the coal, and shaft mines access the coal through a vertical shaft. Mining begins with a cutting machine called a continuous miner creating a box work called room and pillar mining. As the rooms are cut, the coal is loaded onto a shuttle car and carried to a conveyor belt that carries it to the surface. As the mining advances, the pillars remain to support the openings. Roof bolts are placed in the ceiling to stabilize the roof. The larger underground mines use a large coal-cutting machine called a longwall miner. This automated machine is 1000 feet long and has moveable three-foot-wide cutting teeth that cut away at the face of the wall of coal. This 36-inch diameter rotating shearer cuts the coal, where it drops onto a conveyor which hauls to the surface. Because this machine cuts a continuous 1000-foot-long swath into the coal seam, there are no pillars left to support the roof. So moveable metallic roof shields are installed all along the 1000 foot zone that will be cut. This keeps the roof from collapsing near the cutting machine. After each 1000-foot-long cut (each three feet deep), the metal shields are moved forward allowing the roof to collapse behind.
After coal comes out of the ground, general it has been processed. However, the transports cost is very high, and the scene condition is difficult for fixed crushing plant. At this present, mobile crushing plant appear. It can eliminate the obstacles of the crushing places and circumstances, and offer the high efficiency and low cost project plants for the client. So, many miners use mobile coal crusher to process coal.
With 30 years experience in designing and making crushers, SBM mobile coal crusher has been exported to many countries and received high popularity.
