Bull's double header exercise: too much unsupported roof: instructor's copy.
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, Purchase Order Number PO325350, 1995 Jan; :1-35
You work at a mine that has approval to make 34 ft cuts using a remote controlled continuous miner. The roof bolting machine has broken down. The continuous miner has just been refitted with a new cutting head and bits that cut the coal much faster. The two roof bolter operators have been having a hard time keeping up with bull, the continuous miner operator. At the face of #4 entry, bull makes a 40 ft extended cut, trams back from the face, and then turns the miner and cuts the left-hand crosscut all the way through to the #3 entry. When the roof bolter operators discover bull's "double header", they get the section foreman, and then try to plan a safe way to bolt this large area of unsupported roof. Shortly after they complete their assessment and plan of attack, a large roof fall occurs. Now the face crew must decide how to safely clean up the fall while advancing roof support.
Mining-industry; Underground-mining; Underground-miners; Coal-mining; Simulation-methods; Training
Purchase Order Report
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, Purchase Order Number PO325350
Kentucky Department of Mines and Minerals, Lexington, KY