Domestic Main Overflow Ball Mills’ Models

Ball mills are the essential equipment to grind ores. On the basis of discharging ways, ball mills can be classified as overflow ball mills, grid ball mills, and peripheral ball mills. In overflow ball mills, the grinding products freely overflow outside via the neck of the hollow shaft of discharging end. In grid ball mills, grinding products first discharge from the grid plate’s holes in discharging end and then be sent out by the neck of the hollow shaft. While in peripheral ball mills, the grinding products are discharged from the circumjacent holes of the shell in feeding end.

Overflow ball mills are mainly composed of the shell, end cover, main bearing, neck of the hollow shaft, driving gears, feeders and other parts. Their discharging end’s neck of the hollow shaft is bigger than that of the feeding end. When the ore slurry’s level is higher than the lowest point of the discharging end mouth, the slurry will automatically flow out of the mill. According to hydromechanics, finer ore particles have lower terminal velocity than those coarser particles and the finer ore particles in upper pulp will be discharged first. Therefore, overflow ball mills have finer grinding performance, usually used in the fine grinding operation or the secondary grinding process in two-stage grinding process. However, Overflow ball mills can give rise to the overgrinding of minerals or phenomenon. Meantime, they have a smaller capacity and lower discharging speed than grid ball mills of the same specs.

Nowadays, the models of domestic overflow ball mills as follow: MQY270/360, MQY320/450 (NFC Shenyang Metallurgical Machinery Co., Ltd); Φ4500×6400, Φ5030×8000 (China First Heavy Industries); Φ5000×8530, Φ4000×6700 (CITIC Heavy Industries Co., Ltd); 1500×3000, 2100×3000 (Liaoning Liaozhong Heavy Machinery Co., Ltd); MQY4067, MQY4561, MQY3867, MQY3690 (Yantai Xinhai Mining Machinery Co., Ltd); MQY3660, MQY5064 (Shenyang Heavy Machinery Co., Ltd); 1200×1200, 1200×2400 (Henan Qunying Mining Machines); Φ1500×1500 (South Heavy Mining Machinery Company); Φ900×900, Φ900×1800 (Nanchang Heavy Machinery Company); Φ2100×2200,Φ2100×3000(Shenyang Mining Machine Group);MQY2100×3000,MQY1500×3000(Baotou Metallurgical Mining Machinery Manufacturing Co., Ltd);Φ2.1×3.0, Φ2.7×3.6;Φ2700×2100,Φ2700×3600( Janshan Mining machinery Company);MQY1.5×5.7, MQY1.83×7.0 and so on.