Longwall top coal caving or LTCC is a mining method for thick seams in one sequence. It was used as early as in the mid 1950ies in France, later also in other countries such as Hungary, the former Soviet Union and in Slovenia. Over the past 20 years this mining method has been used more and more in China, where it is widely applied today. The method may be used only when the seams are basically flat, the seam range is between 6 - 20m. The typical seam height in the front longwall is typically around 3m. To mine the seam the LTCC longwall is operated directly on the floor and doesn't extend over the full seam height. The coal above the canopies normally cracks while the face is moving; partly this has to be assisted by drilling and blasting. The removal of this top coal is then achieved onto a second rear conveyor.
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