The Jaw Crushers are generally used for crushing stone to make metal for concreting work. The capacity of the jaw crushers is the factor of RPM and the size of the crusher. Demand for different sizes of crushed product differs from time to time. For example, when a major new road is built, demand will differ greatly from the time when normal building construction or road maintenance is carried out. The worst situation is that it is not possible to sell all fractions that are produced. These must be either be sold at low prices or stocked in a dump pile with an environmental impact. Even a small per cent of surplus production will soon cause expensive problem. This material has been expensive to produce. The cost of drilling, blasting, transportation, etc are same as for the prime material.
Much can be gained if the right amount of material could be produced to meet the actual demand, and also accommodate changing demand.
For crushing bigger size metal, Jaw crusher should run at lower rpm. The main drawback is when the crusher is set for bigger size the finer crushed product is more flaky. (Read the advantage of Cubical metal over flaky metal)
For getting cubical crushed product VSI crusher should be used as secondary crusher. Thus we can reduce the crushing ratio, so product is more cubical. First crushing the big rock to 40 mm size, and then again crushing it in VSI can give better quality of crushing. The fines can be reduced in VSI crusher.
With this arrangement there is no unwanted material produced, the crushed material is only as per the demand, and other unwanted material is reduced to Sand. There for all the material can be sold out immediately, with out stocking it in piles. The production of prime material is also increased.
In general a 20X12 crusher gives a out put of 20 tons per hour, Out of this only 35% is 20mm metal ( having more demand). Remaining is unwanted material. With VSI crusher in series, 20 mm metal can be increased to 60 %. This gives a substantial reduction in unwanted material. Automatically there is saving in power lost in crushing.
One jaw crusher of 20X12 size and one VSI crusher can give more production then four Jaw crusher of 20X12 models, with a saving in overall cost of installation, and also saving in power. In addition the produced material is having very good cubical shape.
V.S.I crushers are the best substitute for Jaw crushers for finer crushing. Crushed Product in V.S.I. crusher is cubical compared to Jaw crusher. The main draw back of Jaw crusher is when the Jaws of the crusher are worn out, the crushed product is more flaky.
The V.S.I crusher excels at meeting today's specifications and production need. Complete cubical shape of the crushed product, gradation control, and high production yield per hp can be achieved. Variable production versatility can be achieved in making fine to coarse material. V.S.I. Crushers are unbeatable in making a consistence cubicle particle shape.