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 colloid with each other and shatter in cubical particles. A
Anvil
ring, Shelf ring (pigeon hole ring) are provided to get the particles edges grounded.
The wear cost is a very important criteria in crushing process. Wear cost of other
crushing machines such as Roll crushers, Cone crushers, H.S.I. is very high
compared to V.S.I. Crushers. It is about four to five times more that of VSI crusher.
Rotopactor is a most economical machine for manufacturing artificial sand. In this
machine the stone are thrown at a high speed, those particles colloid with each
other and shatter in cubical particles. Anvils or Shelf ring ( pigeon hole ring ) are
provided. A rubbing action of particles over pigeon ring, grounds the sharp edges
and make the texture smooth.
In our machine a specially designed pigeon ring is provided which uses the
residual kinetic energy in the particle and makes it revolve and role and rub with
each other in a circular path. This makes the shape of the particles very good,
and smooth. The sand manufactured can be of very fine to course grade as per
the requirement of the work. The sand manufacturing process is dry. The process
requires very less water that too only to settle down the residual dust particles in
colloidal state, emitted from the outlet. This machine can allow, slightly wet grit
for crushing. Other machines, Cone crusher, H.S.I. could not use wet material,
as it clogs the machine.
Our V.S.I. Crushers and Rotopactors are more efficient and more economical
in operation. Due to constant development and research our machines are very sturdy and
requires very less maintenance. It is the result of our efforts for constant development
the wear cost of our machine is least. |
