Скачать или смотреть बॉल मिल सिद्धांत और अनुप्रयोग | Pharmaceutical Engineering | B Pharm | Notes

Welcome to Pha_Se_Pharmacy!Ball Mill
Principle
A ball mill works mainly on the principle of Impact and Attrition.
Impact: When feed material is trapped between two balls or between a ball and the wall of the mill.
Attrition: When the balls move at a slow speed and rub against the feed, causing size reduction.


Construction
The ball mill consists of a hollow cylindrical shell made of steel, lined with wear-resistant material (like manganese steel or rubber).
The shell is mounted horizontally on a hollow shaft and supported on heavy-duty bearings.
The shell is partially filled (30–50% of volume) with hard balls (made of steel, ceramic, or stones).
The shaft is connected to an electric motor, which provides rotation.
The inner lining prevents contamination and increases the durability of the equipment.
A feed inlet is provided at one end of the cylinder, and the product outlet is provided at the other end.



Working
The material to be ground is introduced through the feed inlet.
The cylindrical shell rotates around its horizontal axis due to the motor-driven shaft.
As the shell rotates, the balls are carried up the side of the shell and then fall or roll down, striking the material (impact).
The continuous rubbing action of balls also reduces the particle size (attrition).
Finally, the powdered material is collected from the discharge outlet.


Animation Link-    • Ball Mill Workflow 3D Animation-Zoneding M...  
Uses
For grinding crude drugs like barks, roots, and seeds.
In preparation of suspensions and emulsions where fine powder is required.
For manufacture of powders of both synthetic and natural drugs.
Used in preparation of granules for tablets and capsules when fine size distribution is needed.


Advantages
Can handle both wet and dry grinding.
Suitable for hard and abrasive drugs.
Provides uniform and fine size of particles.
Simple operation and can be used continuously.


Disadvantages
Bulky and heavy equipment, not portable.
Requires high energy consumption.
Not suitable for soft, sticky, or fibrous materials (may clog).
Wear and tear of balls and lining occurs.