Assume: A percussion drill jumbo is operating in a drift in a hardrock mine under the...

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Assume: A percussion drill jumbo is operating in a drift in a hardrock mine under the following conditions: Rock: Minnesota quartzite Drilling rate (in Barre granite): 22 mm/sec Drillhole depth: Shift drilling time: Answer the following: 2.7 m 7.2 hr a. What is the output of one drill per shift, measured in total meters of hole? b. If three rounds are required per shift, and each round consists of 68 holes, how many drills must be mounted on the jumbo? c. If the working face is 5.5m X 7.9 m and the tonnage factors is .35m/tonne, calculate the tonnes broken per shift and the drilling factor. d. Will this design make the drilling unit of operation be undersized or oversized? What is preferable and why? Assume: A percussion drill jumbo is operating in a drift in a hardrock mine under the following conditions: Rock: Minnesota quartzite Drilling rate (in Barre granite): 22 mm/sec Drillhole depth: Shift drilling time: Answer the following: 2.7 m 7.2 hr a. What is the output of one drill per shift, measured in total meters of hole? b. If three rounds are required per shift, and each round consists of 68 holes, how many drills must be mounted on the jumbo? c. If the working face is 5.5m X 7.9 m and the tonnage factors is .35m/tonne, calculate the tonnes broken per shift and the drilling factor. d. Will this design make the drilling unit of operation be undersized or oversized? What is preferable and why?