Longwall Mining - Shearers And Ploughs And System Considerations

Longwall mining which has a long history abroad, was used only on a limited scale in the United States until less than 20 years ago. Modern longwall mining in this country can be said to have begun in 1960 with the first installation of self-advancing props in a coal mine in southern West Virginia. In Europe, because of adverse natural conditions, longwall mining is frequently the only practical method, but, in the United States, the system has had to compete economically with highly productive room-and-pillar systems. However, because it is inherently continuous, it has greater productive potential than room-and-pillar systems, and, therefore, although only about 5% of the total U.S. underground production today is the result of the longwall system, its growth potential is great. As mining, by necessity, progresses deeper and must be done under poorer natural conditions, less opportunity will exist for the room- and-pillar system, and the longwall system will have to be used.