The ball mill in the coal mill is a kind of equipment specially used for coal crushing. It is widely used in thermal power stations, the cement industry, the metallurgical industry, the chemical industry, the sugar industry, and other fields. The following is a detailed introduction to the ball mill:
1. Structural composition
Main part:
• Hollow shaft: Made of steel castings, the inner lining is removable and has good wear resistance.
• Cylinder: Lined with a lining made of wear-resistant material, it carries the material and steel balls for rotation.
• Bearings: Use active-aligning double-row radial spherical roller bearings to ensure stable operation of the equipment and low working resistance.
• Driving part: including motor, transmission gear, pulley, V-belt, etc., which provides power to the cylinder.
• Blade: There is an inner spiral in the feed port of the feed end component, which can be called an inner spiral blade, which is used to guide the material into the cylinder.
• Cylinder part: A section of a conical cylinder is added to the discharge end of the original cylinder to make the distribution of media in the cylinder more reasonable. According to the materials and discharge method, a dry coal grinding ball mill and a wet coal grinding ball mill can be selected.
2. Working principle
The ball mill is a horizontal cylindrical rotating device. The material enters the first chamber of the mill through the feeding device and the hollow shaft in a spiral manner. There are ladder linings or corrugated linings in the warehouse, which contain steel balls of different specifications. The centrifugal force generated by the rotation of the cylinder brings the steel ball to a certain height and then falls, which has a heavy impact and grinding effect on the material. After the materials reach coarse grinding in the first chamber, they enter the second chamber through the single-layer partition plate. This chamber is equipped with a flat lining plate and contains steel balls for further grinding the materials. The powdery material is discharged through the discharge grate plate to complete the grinding operation.
3. Performance characteristics
• Wide range of coal types: The ball mill can process coal of various hardnesses to meet different industrial needs.
• Simple structure and easy operation: The ball mill has a relatively simple structure, is easy to operate, and is easy to maintain and maintain.
• Good coal grinding effect: The ball mill can achieve high coal grinding accuracy and production efficiency to meet high-quality production needs.
• Good airtightness: The ball mill has good airtightness, which reduces dust leakage and is beneficial to environmental protection.
4. Technical parameters (example)
The specific technical parameters will vary according to the model and specifications of the ball mill, but generally include the following aspects:
• Cylinder diameter: such as Φ2.2m, Φ2.4m, etc.
• Cylinder length: determined according to processing capacity, such as 3m, 4.5m, etc.
• Motor power: Depends on the equipment model and processing capacity, such as 300kW, 500kW, etc.
• Output: The amount of coal processed per hour, such as 20t/h, 30t/h, etc.
5. Application areas
Ball mills are widely used in pulverized coal preparation systems in thermal power plants. They are also important equipment in pulverizing systems such as the cement industry, metallurgical industry, chemical industry, and sugar industry.
