Secondary Gyratory Crushers

The use of large primary crushers made secondary crushing necessary, but this department was taken care of nicely by the existing lines of standard gyratory machines. In commercial crushed stone plants, there was gradual increase in the number of products, but generally a sufficient demand existed for the coarser grades for ballast and macadam roads to absorb the output. So for a time everything went along quite comfortably in this respect, and the operator concerned himself with the problem of getting out increased tonnage, selling his product as it was made, or stocking it during off-seasons for any particular grades. Then came reinforced concrete, and with it a rapidly increasing demand for small sizes of crushed stone and gravel. It is hard to say when this demand began to assume sizeable proportions, but soon commercial plants began to feel the effects of it, and to look for a remedy. For some time, as was quite logical, the remedy consisted of installing more small secondary crushers, generally small gyratories. This procedure assumed rather startling proportions in some large plants. For example, the array of crushers in the plant comprised one 48″ primary, four No. 7.5 secondaries and a battery of finishing crushers … Continue reading Secondary Gyratory Crushers