Rubber Liner for Ball Mill
Ball mills are widely used in the industrial sectors as of non-ferrous metals mines, ferrous metals mines, cement plants and power generation plants. Mills can be classified into ball mills, autogenous mills and SAG mills based on the ways in which ore is ground. Based on the functions of ore grinding, there are primary grinding mills and regrinding mills. Viewed from the ore discharging methods, there are overflow ball mills and grate ball mills.
1. Features of rubber liner for ball mill:
Compared with metal liners, rubber mill liners made of premium native rubber and molded with the vulcanizing process have the following advantages:
1.1 The density of a rubber liner is only 1/6 of that of a metal liner, and the lighter mass offers an easier installation and disassembly;
1.2 The damping and absorbing functions of rubber liners reduce noise, and the noise from rubber liners is normally lower by 10-15dB than that from metal ones;
1.3 The corrosion resistance of rubber liners are much higher than that of metal liners, and can suit both acid and basic slurry conditions;
1.4 Rubber liners have higher capacity of anti-wearing by fatigue and anti-wearing by grinding than metal liners, especially in the case of hard ore, when rubber liners will generally provide a service life 2-4 folds longer than that of metal ones. However, its capacity of anti-wearing by rolling and pressing is weaker, and it can not hold well repeated impact by large steel balls. Therefore, rubber liners are applied more on both feed-end and discharge-end heads of primary ball mills, on both feed-end and discharge-end heads and shells of regrinding mills and the discharge-end head of autogenous mills.
2. Conditions applicable for rubber liner of ball mill:
2.1 Hardness of ore: The relationship of the rates of wear and the hardness of ore for both rubber mill liners and metal mill liners is illustrated in Figure 1. The comparison of rubber mill liners with metal mill liners shows that the harder the ore is, the better wear resistance the rubber liners offer than the metal ones do. Therefore rubber liners are more suitable for application in an environment where the hardness is higher in a ball mill;
2.2 Diameter of steel ball: The steel balls selected for a rubber-lined mill should generally be about 100mm in diameter. Refer to Figure 2 for more info;
2.3 Slurry temperature: The temperatures inside a ball mill with rubber liners should generallyrange within 80 deg C;
2.4 Slurry pH: The slurry pH in a ball mill with rubber liners may range between 2-14.
3. Structural characteristics:
To a large extent, the life of rubber liners depends on their structural modes, among which the height B of the lifter bar, the spacing A between two lifter bars and the shape of the lifter bar play a major role. Figure 3 shows a typical cross section of rubber mill liners. A rationally designed height of the lifter bar not only raises the grinding efficiency of a ball mill, but also extends the service life of rubber liners. Refer to Figure 4 for the schematic view of the status of material movement.
4. Concerning the application of mills under different conditions, we have designed mill liners with a variety of specifications. They consist of rational compositions and are highly wear-resistant, while the framework material in mill liners applies structural sections of premium aluminum alloy. Refer to the following figures for the views of some rubber mill liners produced by our company.