Lesson 1/Learning Event 1
run rock, a primary jaw crusher will be needed for the initial stage of reduction in the plant. If the raw material is
smaller river run gravel, the secondary roll crusher may be the only crusher needed for the crushing operation.
The extent of the processing required to produce the desired aggregate size will indicate the amount and types of
equipment you need. For crushing 4-inch minus base course material, a primary jaw crusher may be sufficient to
achieve the desired results. If 1-inch minus aggregate is to be produced from quarry run rock, a primary jaw
crusher and a secondary roll crusher will be required. If the crushed aggregate must be washed, a washing unit
will be needed. If an existing stockpile of aggregate must be sorted into different sizes of aggregate, a screening
unit will be needed to accomplish this task satisfactorily. You must determine the nature of the processing to be
accomplished in order to select the necessary equipment to do the job.
The last step in the equipment selection phase of plant layout and design is to chart the flow of material through
the plant. The flow chart should start where the raw material first enters the plant and terminate at the stockpile of
finished product. This chart is useful in determining the amount of conveyors that will be needed to transport the
rock between the various pieces of equipment, and between the equipment and the stockpiles. During this phase
of planning you should determine the equipment configuration within the facility. You should also consider the
amount and types of equipment that will be needed to load haul units, keep stockpiles maintained, and the amount
of equipment that will be needed to construct the facility.