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In cement plants, mineral processing plants, thermal power plants, and chemical plants, the proportion of steel balls used in ball mills must be determined based on factors such as the diameter of the mill grinding surface, the hardness of the ore, the particle size of the ore fed into the mill, the hardness (quality) of the steel balls, and the rotation speed of the mill. Once the model of the ball mill is determined, its rotation speed is also fixed, and the hardness of the ore can be measured. The ore particle size for the ball mill is determined by the mesh size of the screening screen. Typically, a newly installed ball mill goes through a running-in process. During this period, the steel balls are added for the first time; the quantity added constitutes 80% of the mill’s maximum ball load. The proportion of steel balls added can be determined based on their sizes (ф120mm, ф100mm, ф80mm, ф60mm, ф40mm). Amount of steel balls added: Different ball mill models have different total amounts of balls installed. For example, the MQG1500×3000 ball mill (with a processing capacity of 100–150 tons) has a maximum loading capacity of 9.5–10 tons. For the first addition, large steel balls (φ120mm–φ100mm) account for 30%–40%, medium-sized balls of 80mm account for 40%–30%, and small balls (φ60 and φ40mm) account for 30%. The reason why only 80% of the steel balls are added during the grinding machine’s commissioning phase is that the grinding machine needs to be properly installed, with its large and small gears meshing properly; moreover, the amount of ore fed into the machine also needs to be increased gradually. After the grinding machine has been running continuously for two to three days, it should be stopped to check the condition of the gear meshing. Once everything is in order, the access cover of the grinding machine can be opened to add the remaining 20% of the steel balls. Once the ball mill is running properly, steel balls should be added in a ratio of 3:4:3 per shift (3 for ф120mm balls, 4 for ф100mm balls, and 3 for ф80mm balls). Note: The addition of small steel balls is only for use during the first ball addition. Because, during the normal operation of the ball mill, the appropriate friction generated between the steel balls, between the steel balls and the ore, and between the steel balls and the mill liners leads to increased wear, causing large balls to become smaller (turning into medium-sized balls) and medium-sized balls to become even smaller. So under normal circumstances, there is no need to add more small balls. The use of small balls is applicable when the particle size of the useful minerals has not undergone individual dissociation; when the fineness achieved by the mill does not meet the requirements for flotation, an appropriate amount of small balls can be added. In a ball mill, the steel balls wear down continuously during operation. To maintain the ball loading rate and an appropriate ratio of balls, as well as to ensure stable operation of the ball mill, it is necessary to replenish the balls appropriately in order to compensate for the wear. The amount of steel balls added is determined based on their mass; the quality of these steel balls influences the quantity required per ton of ore. It is best to use new type of wear-resistant steel balls. The optimal amount of high-quality steel balls to add is calculated based on the amount of ore being processed (that is, 0.8 kg per ton of ore). Generally, 1 kg–1.2 kg of steel balls are required to process one ton of ore. Ball mill models vary depending on the size ratio of the steel balls, and their configurations differ as well. The diameter of the ball mill is 2500 mm or less, and the sizes of the steel balls used are ф100 mm, ф80 mm, and ф60 mm. The ball mills have a diameter of over 2500, with steel balls of sizes ф120mm, ф100mm, and ф80mm being used. Sales Director: Cao Qingfu 13658620726