Lesson 2/Learning Event 3
FINAL GRADATION CHECK
Since the new product contains an additional 1.6 tons per hour of by-product size material, a final gradation check
must be made. The new product is increased to 27.4 tons per hour.
Because the new product contains more particles than originally anticipated in the 3/8 inch size, #4 has been
included in the gradation check. Assume that one-half of the 1.6 tons of by-product in the product stockpile is +
#4 aggregate and one-half is smaller than #4 aggregate. Thus, the 0.8 tph is found in the + #4 row in the table
above. Checking against your product specifications,
you find that the specifications will be met. The estimated production range is 27.4 tph of usable product.