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Indiana University Studies 



Another firm suggested the use of a jaw crusher and a swing- 

 hammer pulverizer, but the cost of the pulverizer made the entire 

 investment a little higher than the above estimate. 



The following figures are for a large plant turning out from 20 

 to 25 tons per hour. The prices are subject to the discounts 

 given by the firm, and are for the material free on board cars at 

 the manufacturing plant: 



One steel breaker for heavy duty, set to crush to 2-iiich size and 

 handling 25 tons per hour; size 20x20 inch; horse-power 18; speed 



150 revolutions per minute; weight 12 500 pounds $1,407 



One No. 2 ring-roll mill, horse-power 75; speed 325 revolutions per 



minute; weight 45,000 pounds 8,857 



Four separators, weight 7,200 pounds ($479) 1,916 



One elevator, horse-power 10; weight 2,200 pounds 395 



Pulleys, belts, and supports 325 



Building and bins, including labor . 2,000 



Freight, foundations, and cartage . . . 950 



Total outlay . . $15,850 



Fixed charges — 



Interest at 6 per cent $ 951 . 00 



Depreciation at 9 per cent 1,426.50 



Taxes and insurance at 2 per cent 317.00 



Total fixed charges $2 , 694 . 50 



Operating charges — 



Labor at $2.00 per day ... $5 , 544 . 00 



Power at $40.00 per borse-power per year 4,320.00 



Wear and repairs 810.00 



Oil and waste ... 98 . 00 



Total operating expense for 1 year of 308 days of ten hours 



each $10,772.00 



The total yearly output is 77,000 tons. The cost is shghtly 

 under 14 cents per ton. To this must be added the fixed charges 

 of about 3 cents per ton which brings the total cost up to approxi- 

 mately 17 cents per ton. This figure is sufficiently high because 

 the liberal discounts and the fact that the estimates on the other 

 costs are very conservative would tend to reduce the cost in case 

 of the actual construction of such a plant. 



Breakers of the type included in the above estimate are made 

 in capacities of from 6 to 40 tons per hour, and the prices range 

 from $715 to $2,572. In cases of large output, roll jaw fine 

 crushers are often used, following the breakers, before the product 



