There are significant differences between SAG mills and ball mills in many aspects. SAG mills and ball mills have significant differences in structure, operating principle, grinding media, application scope, advantages and disadvantages. When choosing grinding equipment, factors such as material characteristics, grinding requirements and production scale should be considered comprehensively to ensure efficient operation and cost-effectiveness of the equipment.
SAG mill and ball mill structure and composition
SAG mill: mainly composed of motor, reducer, large diameter grinding disc, etc. Its cylinder structure is usually single-cylinder type, and there is also a double-cylinder structure, with lifting plates and lining plates installed inside to assist the grinding process.
Ball mill: includes feeding device, cylinder, motor and other components. The grinding body diameter of ball mill is usually smaller than that of SAG mill, but its structure is also simple and easy to operate.
Operation principle of SAG mill and ball mill
SAG mill: relies on the weight and centrifugal force of the grinding disc to grind materials. During the grinding process, the ore and a small amount of steel balls are lifted to a certain height and then fall, and the ore is crushed by impact force and grinding force. SAG mills can achieve two-stage grinding, namely coarse grinding and fine grinding.
Ball mills: Grinding is performed through the circular motion of the grinding body. When the cylinder rotates, the internal grinding media (such as steel balls) impact, squeeze and grind the material, thereby crushing the material to the required particle size.
SAG mill and ball mill grinding media
SAG mill: Use a mixture of ore and steel balls as grinding media. The ore itself also plays an important role in grinding during the grinding process.
Ball mill: Mainly uses steel balls as grinding media. The number, size and type of steel balls can be adjusted according to the material characteristics and grinding requirements.
Scope of application of SAG mills and ball mills
SAG mills: Mostly used in the coarse and medium-fine grinding stages of metal mines, non-metallic mines and building materials industries. It is particularly suitable for processing ores with high hardness and large block size, such as copper mines, gold mines and other non-ferrous metal mines.
Ball mills: Widely used in cement, power, chemical industry, ceramics and other industries. It is suitable for the fine grinding stage of various ores and can process ores of various hardness, including metal ores and non-metallic ores.
Advantages and Disadvantages of Semi-autogenous Mill and Ball Mill
Semi-autogenous mill:
Advantages: High grinding efficiency, suitable for processing large ores; can reduce the crushing link and simplify the process; compared with the ball mill, it reduces the use of steel balls and reduces the operating cost.
Disadvantages: The consumption of steel balls is still large (although less than the ball mill), and the operating cost is relatively high; the internal wear of the mill is fast and requires frequent maintenance.
Ball mill:
Advantages: Simple structure, continuous operation; strong adaptability, stable performance; easy to achieve large-scale and automatic control; the grinding product has a fine particle size and can achieve a higher grinding fineness.
Disadvantages: Large consumption of steel balls and high production costs; the appropriate type and size of steel balls need to be selected according to the characteristics of different ores; for ores with higher hardness, it may be necessary to add a crushing link to improve the grinding efficiency.
