Crushed Material from Jaw Crusher / Cone Crusher are more flaky. Flaky material cannot be used for road constructions. Due to heavy load flaky material brakes the broken surface do not have asphalt. This reduces the life of the road. Now a days Government banned jaw crushers material or cone crushers material for the construction of roads. Metal used for road constructions must be manufactured from VSI Crusher only. Crushed product from VSI Crusher is cubical and flakiness index is within permissible limit. The permissible limit of the flakiness index must be below 30. This means flaky particle should not be more than 3% in the crushed product. It cannot be achieved from JAW Crusher or Cone Crusher. Only VSI Crusher can produced cubical particles.
VSI manufactured by Akashganga are more efficient and gives desired results. Above criteria of crushed metal is also followed in dam & bridge construction. The porosity of concrete made with VSI metal is very less and dense concrete is achieved. Automatically more strength of the concrete is achieved.
This can be proved with the help of following example. Flaky material means chip of the stone having more length and width compared to thickness. Let us take a piece of stone having length 2 units X 1unit X 0.5 unit So the Volume of this particle will be 2 X 1 X 0.5 = 1 cu unit. At the same time the surface area of this particle will be 7 sq. unit. ( 2 X 2 X 1 + 2 X 2 X 0.5 + 2 X 1 X 0.5 = 7 sq unit.) For the Same volume if we select a cubical particle it's length breath and height will be 1 Unit. So the Volume comes to 1 X 1 X 1 = 1 Cu unit. And surface area is 1 X 1 X 6 = 6 Sq. Units.
Thus for the same volume the surface area of the particle is increased by 16% approximately. Crushed metal from Jaw crusher is generally flaky, and from V.S.I. Crusher is cubicle. There fore there is 10 to 15% more strength for the same cement or asphalt Consumption. There is also a problem with flaky material while rolling it gets break and the broken surface do not have any coating of asphalt, makes the section weak. Hence more life of the road can be achieved by using the cubicle metal. Again less voids in the cubical metal so more dense concrete, so more strength. For Crushing 6,000 CFT (approx. 250 tons) of 20 mm metal per day requires minimum for crushers of 20X12 or 24X10 size. The unwanted material produced is about 65% . Total H.P. required to run four crushers is about 120 H.P. ( Excluding Conveyors and Grading Screen etc)
Above can be replaced by One Jaw Crusher and One VSI crusher, So the total H.P. required is only 90. It can give same production, and unwanted material is reduced to 40%. If in addition to this unit a Rotopactor is installed, which can convert unwanted material to sand. It will require 40 H.P. Thus total H.P. will be 130 H.P. Total cost of this set is same, but the raw material cost is reduced by 40% (due to unwanted material not produced). And as all material produced is have immediate demand, the profit increases by 40%. The storing cost and selling at low rate is avoided, and with no environmental impact. The cost of production is also reduced to a substantial (wearing of Jaws and other parts of Crusher).