Artificial Sand Making Machine
Natural sand are weathered and worn out particles of rocks and are of various grades or size depending on the accounting of wearing. The main natural and cheapest resource of sand is river. Dams are constructed on every river hence these resources are erasing very fast. Now a days good sand is not readily available, it should be transported from long distance. Those resources are also exhausting very rapidly. So it is a need of the time to find some substitute to natural river sand.
The artificial sand produced by proper machines can be a better substitute to river sand. The sand should be sharp, clean and course. The grains should be of durable material. The grain sizes must be such that it should give minimum voids. The presence of clay and silt retards the setting of the cement and makes the mortar weaker and the walls or the slab leaks and holds dampness.
The sand in the mortar does not add any strength but it is used as an adulterant for economy and with the same it prevents the shrinkage and cracking of mortar in setting. The sand must be of proper gradation ( it should have particles from 150 microns to 4.75 mm in proper proportion) When fine particles are in proper proportion, the sand will have less voids. The cement required will be less when there will be less void in sand. Such sand will be more economical.
Only sand manufactured by V.S.I. Crusher is cubical and angular in shape. Sand made by other types of machines is flaky , which is troublesome in working. There is no plasticity in the mortar. Hence the mason are not ready to work with machine made crushed stone sand. For the same reason inferior river sand may be used. Manufacturing sand from jaw crusher, cone crusher, roll crusher often contains high percentage of dust and have flaky particle. Flaky and angular particles may produce harsh concrete, and may result in spongy concrete.
There is standard specification for Fine aggregates (Sand). It is divided in four gradations. Generally known as Zone I, Zone II, Zone III and Zone IV. There is sieve Designation for each grade. Gradation is made as per the use of the sand. There are testing sieves for testing the sand. A set of Sieves with square hole is available. Followings are the sieves :
- 4.75 mm, 2.365, 1.1830, 600 microns, 300 microns, 150 microns
- Pan
Specific percentage are designated for each size for each Zone sand in terms of material retained or passed `from the sieves.
| Zone One Sand | ||
| Sieve size | Percentage retained | Percentage passing |
| 4.750 | 10 % | 90-100 % |
| 2.365 | 40 % | 60-95 % |
| 1.1830 | 70 % | 30-70 % |
| 600 microns | 66-85 % | 15-34 % |
| 300 microns | 80-90 % | 5-20 % |
| 150 microns | 90-100 % | 0-10 % |
| Zone Two Sand | ||
| Sieve size | Percentage retained | Percentage passing |
| 4.750 | 10 % | 90-100 % |
| 2.360 | 25 % | 75-100% |
| 1.1830 | 45 % | 55-90 % |
| 600 microns | 41-65 % | 35-59 % |
| 300 microns | 70-92 % | 8-30 % |
| 150 microns | 90-100 % | 0-10 % |
Where concrete of high strength and good durability is required Sand used should be of proper gradation. The concrete mix design should be done properly. When the sand of finer grade is used, the ratio of finer to coarse aggregates should be reduced. The fine to coarse ratio depends upon the particle shape, surface texture of both fine and coarse particles. The gradation of coarse and fine aggregate is very important. Very fine sand is not recommended for concrete purpose.
The fines content in the sand below 600 microns should be about 30 to 50 %. This will be a ideal sand for concrete work as well as masonry and plaster work. At present it is generally observed that the fine content in river sand below 600 microns are very less. Such sand should not be used for concreting work. Our Rotopactor Produces perfect sand of required gradation. Sand of any Zone can be produced. Sand from our Rotopactor is a perfect substitute for river sand.
The Civil engineers, Architects , Builders, Contractors agrees that the natural sand, which is available today, is deficient in many respect. It do not contents the fine particles, in proper proportion as required. Presence of other impurities such as coal, bones, shells, mica and silt etc makes it inferior for the use in cement concrete. The decay of these materials, due to weathering effect, shortens the life of the work. Now a days, Government have put ban on Dragging sand from River bed. Due to dragging of the sand, from river bed reduces the water head, so less percolation of rain water in ground, which result in lower ground water level. In some places it may be up to 600 ft deep. The roots of the tree may not be able to get water. The water flowing in the river may be covered with sand so it is less exposed to Sun. In the absence of sand, so more water gets evaporated due to direct sunlight. The rain water flowing in the river contents more impurities. when it passes through Sand bed it gets filtered. ( In water supply schemes the water is filtered in sand bed only) If there is no sand in river bed, water will not be filtered. Such water may be harmful for drinking purpose. Due reduced water level in ground, may result in draft, even scarcity of drinking water, so Government have to supply water by tanker. Which is more expensive compared to the royalty collected for sand. Vastu Shastra: Now a days Vastu Shastra is more popular, followed by so many persons for constructing a house. As per Vastu shastra the Building material must be free from traces of human body or animal body. The River sand contains Bones of human beings and animals. The shells are also one kind of bone. It is not easy to take out all such things present in the river sand. The best solution for this is to use Artificial crushed sand of good quality. Only the long term substitute for river sand is manufactured sand or crushed sand from V.S.I. Crushers. The manufactured sand must have cubical particles or spherical particles which can be generated only from V.S.I. Crushers only Due to Cleavage crushing. Due to cleavage breaking of the particle the surface is more smooth. Sand manufactured from any other process/ machine can not have cubical shape. Fine aggregates manufactured by Compression crushing ( Jaw crusher, Cone crusher, Roll crusher, Hammer mill ) is flaky and more angular in shape. The surface texture is very rough. There fore such fine aggregate is not suitable for concreting and other construction work. The Plasticity of concrete reduces and results in honey combing.
So the process of manufacturing should be such that it should give Cubical particles. Flaky particles increases voids over cubical or spherical particles about 5 to 6 percent more, and reduces the strength of concrete.
Vertical shaft Impactor principle is used for crushing bigger particles, for shaping the crushed metal ( giving better shape of the particle ) and for crushing fines aggregates below 4.75 mm. It is best machine for making sand from stone. Sand manufactured by Vertical Shaft Impactor is of cubical shape. Such sand can be used for all types of construction work, Concreting, Plastering etc and is better substitute to river sand. V.S.I. Crushers is a most economical machine for Crushing Stone in Cubical shape and manufacturing artificial sand. In this machine the particles are thrown at a high speed. Those particles colloids in crushing chamber on anvil or stone lining. Rubbing of the particles with each other grounds the edges and also the surface texture.
Our Machines are very specially designed reduces the wear cost. The wear sector of rotor have very long wear life and are patented. Rotor of VSI Crusher is also known as a heart of the machine. Rotors in our machine are very especially designed. The wear cost of our machine is very less compared to all other manufacturers. The wearing cartridge is oil cooled. This makes our machine very different from all other manufacturers. The overall design of our machine is very special and can be accompanied by dust separating system. This is a unique patented design which gives manufactured sand clean and free from fine dust. This makes our machine very unique in the market.
Our VSI Crusher has very unique patented design of fixed type distribution cap which reduces the wear cost compared to other machines in the market. That is the reason we have got our innovative design patented under the head “ SPECIALLY DESIGNED VSI CRUSHER “
