ACT PPT.pdf of sir bhavsinhji polytechnic institute bhavnagar.

to use in my education and use as a reference.

2. DABHI KULDIP R. (236490306052)
CHAVDA VIVEK H. (236490306045)
BAMBHANIYA NAMAN J. (236490306008)

3. Aggregates are the main ingredient in
construction materials like concrete, mortar, and
road works.
They are produced by crushing, screening, and
processing of rocks and stones.
Properly graded aggregates improve strength,
durability, and workability of construction
materials.
For large-scale production, specialized
equipment and machinery are used to achieve
uniform size and quality.
Common equipment includes crushers, screens,
conveyors, and washing plants.

4. Jaw Crusher
Gyratory Crusher
Roll Crusher
Cone Crusher
Impact Crusher

5. 1.Jaw Crusher :
It consists of two jaws, one fixed and the other moving.
It is mainly suitable for primary crushing.
It is widely used for hard stones, rocks, and coarse aggregates.
Common jaw size: 1.68 m ×2.14 m.
It has a very high crushing capacity.
It can crush even very large boulders into small sizes.
Power consumption is minimum.

6. 2. GYRATORY CRUSHER :
A gyratory crusher is a type of primary crusher used in aggregate
production and mining.
It works on the principle of crushing by compression.
It is suitable for large-scale operations because of its high capacity.
For crushing, a cone-shaped head is fixed.
The head inside the bowl crushes the material.
Stones are broken due to the impact of the head.
The head is continuously in motion.
Because of the rotation of the head, the stones are crushed.

7. 3. ROLL CRUSHER :
A Roll Crusher is a type of secondary crusher used for medium and fine
crushing of rocks.
It consists of two cylindrical rolls that rotate in opposite directions.
Material is fed between the rolls and is crushed by compression and
shear force.
In this crusher, stones are pressed and crushed between two rollers.
The rollers are fixed on shafts rotating in opposite directions.
Power is transmitted to the rollers through a V-belt.

8. 4. CONE CRUSHER:
A Cone Crusher is a type of secondary and tertiary crusher.•Itworks on
the principle of compression crushing.•Itis mainly used for producing
uniform, fine, and
well-shaped aggregates.
Used for medium and fine crushing of stones.
Gives uniform size of crushed stones.
The conical head inside the machine is mounted on
the upper side of the shaft and rotates slowly.

9. 1. Type and Nature of Material :
Hardness (soft, medium, or hard rock)
Abrasiveness
Moisture content
2. Required Size of Output Aggregate :
Coarse, medium, or fine crushing
Desired particle shape
3. Capacity of Crusher :
Tons per hour required
Suitability for small, medium, or large projects
4.Stage of Crushing :
Primary, secondary, or tertiary crusher requirement

10. 5. Power Requirement :
Energy consumption efficiency
6. Maintenance & Operating Cost :
Availability of spare parts
Ease of maintenance
7. Mobility & Space Requirement:
Fixed (stationary) or mobile crusher
Foundation and installation needs
8. Cost of Machine & Plant Setup:
Initial investment
Overall plant cost vs. project budget

12. 1 .BALL MILL :
•Introduction :
A Ball Mill is a cylindrical rotating drum used for fine grinding of
aggregates and minerals.
It reduces larger aggregates into powder or very fine particles by
impact and attrition.
•Construction :
Cylindrical Shell –Horizontally mounted, made of steel.
Liner –Inner surface lined with steel or rubber plates to
reduce wear.
3. Grinding Media –Filled with steel balls of varying
sizes.

13. 4. Feed Inlet –For feeding stone pieces or clinker.
5. Discharge End –Crushed fine aggregates come out here.
6. Driving Mechanism –Motor with gears rotates the shell.
Working Principle :
As the shell rotates, steel balls lift and fall on the aggregate.
Material is crushed due to impact (falling balls) and attrition
(friction between balls and aggregates).
Produces very fine, uniform material (even powder).

15. 2 . ROD MILL :
Introduction :
A Rod Mill is similar to a Ball Mill but uses long steel rods as
grinding media.
Produces coarser aggregates compared to Ball Mill.
CONSTRUCTION :
Cylindrical Shell –Horizontal drum with metallic lining.
Grinding Media –Steel rods slightly shorter than shell length.
Feed Inlet –For stone pieces.

16. Discharge End –Produces fine aggregate
of sand size.
Driving Mechanism –Motor and gears
rotate the shell.
WORKING PRINCIPLE :
As the shell rotates, rods tumble inside.
Crushing occurs by line contact between rods and aggregates
(not point contact like balls).
Material is gradually broken down to sand-sized aggregates.
Can be operated in dry or wet condition.

17. INTRODUCTION :
After crushing, aggregates are of different sizes.
Screens are used to separate, classify, and grade
aggregates into required sizes.
They work on the principle of sieving or screening
using perforated plates, meshes, or vibrating
surfaces.

18. TYPES OF SCREENS :
1.Revolving Screen:
A cylindrical drum made of wire mesh or perforated
steel plate.
Drum is inclined and rotates slowly.
Aggregates fed at one end → smaller particles pass
through holes larger particles move to the other
end.
Use: Simple, low-cost, suitable for coarse
separation.

19. 2. SHAKING SCREEN :
A flat or slightly inclined surface with a wire mesh.
Screen is moved with shaking/vibrating motion.
Aggregates are fed on top → smaller particles fall through →
larger particles move off the screen.
Use: For medium-scale aggregate plants.

20. 3. VIBRATING SCREEN :
Most modern and widely used.
Consists of a rectangular mesh surface mounted on springs.
Powered by motor → screen vibrates rapidly.
Ensures continuous movement of material → efficient
separation.
Use: For large-scale aggregate production (road, dam, and
concrete works).

21. Introduction :
A log washer is a washing equipment used to remove clay, silt, and other
impurities from coarse aggregates.
It is mainly used when aggregates are covered with sticky clay or soft
particles which cannot be removed by ordinary washing.
Construction :
Consists of a long, inclined tank/trough.
•Inside the tank, two counter-rotating shafts (logs) are
provided.
•Each shaft has blades or paddles fixed spirally along its
length.

22. Water is continuously supplied at the lower end.
Working Principle :
1. Aggregates are fed into the tank.
2. As the logs rotate, the paddles agitate, scrub, and rub the
aggregates against each other.
3. This action breaks down clay lumps and removes coatings
from aggregate surfaces.
4. Clean aggregates move upward and discharge at the top
end.
5. The dirty water with clay and silt flows out from the lower
end.