Your company will be moving 416,000 Icy of earth from a borrow pit. Your company has a loader with a rated bucket capacity of 7.46 Icy and the material has a fill factor of 0.96. The set-up at the borrow pit is such that the loader cycle time will be 36 seconds. Haulers with a capacity of 41 Icy will be used to haul the material. Some preliminary studies show that the hauler tire penetration is 4 inches in both loaded and unloaded states. When loaded, the hauler will travel up a grade of 7% for 1900 ft, then travel up a grade of 12% for 1300 ft, then travel down a grade of 5% for 1650 ft where the hauler will dump it's load. The hauler will return on a different haul road. When empty, the hauler will travel down a 7% grade for 550 ft, then down a 12% grade for 2540 ft, then up a grade of 5% for 1525 ft. The hauler will then be at the stockpile to be loaded. The hauler dump time is 1.75 minutes. The efficiency factor used by your company is 0.86. Determine the hourly productions (Icy/hr), hourly costs, and unit costs for conditions above and below the bucket balance point and the hauler-loader balance point. Place all values in the tables below. How many work hours will it take to move the material and what equipment (loader or haulers) will govern for the lowest unit cost? Assume $275/hr for loader and $190/hr for hauler and material weight 2,300lbs/Icy. The speed chart for 7726 hauler can be found in the CAT manual (Edition 44). Hourly Production (Icy) Number of Buckets No. of Haulers Hourly Cost ($) Number of Buckets No. of Haulers Unit Cost ($/Icy) Number of Buckets No. of Haulers oject duration: HOURS Your company will be moving 416,000 Icy of earth from a borrow pit. Your company has a loader with a rated bucket capacity of 7.46 Icy and the material has a fill factor of 0.96. The set-up at the borrow pit is such that the loader cycle time will be 36 seconds. Haulers with a capacity of 41 Icy will be used to haul the material. Some preliminary studies show that the hauler tire penetration is 4 inches in both loaded and unloaded states. When loaded, the hauler will travel up a grade of 7% for 1900 ft, then travel up a grade of 12% for 1300 ft, then travel down a grade of 5% for 1650 ft where the hauler will dump it's load. The hauler will return on a different haul road. When empty, the hauler will travel down a 7% grade for 550 ft, then down a 12% grade for 2540 ft, then up a grade of 5% for 1525 ft. The hauler will then be at the stockpile to be loaded. The hauler dump time is 1.75 minutes. The efficiency factor used by your company is 0.86. Determine the hourly productions (Icy/hr), hourly costs, and unit costs for conditions above and below the bucket balance point and the hauler-loader balance point. Place all values in the tables below. How many work hours will it take to move the material and what equipment (loader or haulers) will govern for the lowest unit cost? Assume $275/hr for loader and $190/hr for hauler and material weight 2,300lbs/Icy. The speed chart for 7726 hauler can be found in the CAT manual (Edition 44). Hourly Production (Icy) Number of Buckets No. of Haulers Hourly Cost ($) Number of Buckets No. of Haulers Unit Cost ($/Icy) Number of Buckets No. of Haulers oject duration: HOURS
