Beneficiation Of Mining Machines At The Ireland Mine By Design Changes

The Ireland Mine is located some seven miles South of Moundsville West Virginia, along the bank of the Ohio River. We are mining the Pittsburgh #8 seam. This seam is approximately 60" in thickness, and is immediately overlain by some 10 feet of a conglommerate material. The roof is difficult to control, due to the fact that it frequently is composed of substances not hard enough to be held together with 6-foot roof bolts. In many cases, we must use 10-foot roof bolts, in order to get bolt anchorage in the limestone above the conglommerate. Due to the elasticity of the limestone and its tendency to bend rather than to break, we have been unable to maintain a pillar line. Thus, we have found it necessary to mine by the room and pillar system. Belt haulage is used on room entries to automatic loading stations, thence into 15-ton mine cars, controlled at the loading point by car spotters. The maximum belt length is 2,000 feet. Rail haulage to the slope-bottom dump is by 27- and 50-ton locomotives. The mine produces coal two shifts per day, with 7 production crews on each shift. Mine and machinery maintenance is performed on the Midnight shift. We handle an average of 660 tons per machine shift.