How to perform ball mill noise reduction

As an indispensable grinding equipment in the beneficiation process, the ball mill brings economic benefits to the beneficiation plant. The ball mill is mainly used for grinding materials in the industrial production process. Due to the large volume and heavy tonnage of the ball mill, the noise during the production process is relatively large. The noise generated is generally above 95dB (A) and can exceed 1MdB (A). One of the strong noises in industrial production. It seriously affects the physical and mental health of the staff, and the problem of reducing the noise of the ball mill needs to be solved urgently.

Ball mill noise source

The main source of the ball mill noise is the mechanical noise caused by the impact of the steel ball in the drum with the cylinder wall liner and the processed material. This sound spreads outward along the liner, the tube wall, and the inlet and outlet, which include: the impact of the material, the impact between the steel ball and the steel ball, the steel ball and the inner steel plate, and the friction sound. In addition, there are sounds from the motor, and vibration noise of the conveyor during the operation of the equipment.

1. Design sound insulation room. When conditions permit, the ball mill is concentrated in a special ball mill room, and the ball mill room is transformed into a special sound insulation room. The effect will be better than the sound insulation cover. However, attention must be paid to solving the problems of monitoring, indoor heat dissipation and maintenance of the ball mill during operation. The interior wall of the sound room is a sound-absorbing material, which can reduce the reflected noise on the indoor wall and the top surface, reduce reverberation, and reduce the sound pressure level in the entire ball mill room. The external wall is a sound insulation layer, which radiates outward through the sound absorption layer. Low and medium frequency noise is blocked indoors.

2. Reduce noise from the sound source. There will be noise when the collision occurs between the inner wall of the cylinder and the lining plate. Using the cylinder muffler method can effectively remove the noise of the ball mill, which is to install an elastic buffer between the inner wall and the lining plate; a rubber lining plate can also be used instead of dream Steel lining to reduce noise.

3. Set the elastic layer. Place a heat-resistant soft rubber mat between the inner surface of the ball mill drum and the liner. In order to prevent the soft rubber mat from overheating, place an industrial felt with a thickness of 10-15 mm between the ball mill liner and the soft rubber mat. The noise is reduced below the allowable standard.

4. Add sound insulation cover. A steel structure skeleton is used, and a thin steel plate is used as an outer shell, and a damping layer and an ultra-fine glass wool or other sound absorbing materials are filled inside to seal the whole ball mill. Because the ball mill generates a large amount of heat during operation, attention must be paid to the heat dissipation in the hood and the convenience of equipment maintenance.

5. Cover the drum wall with a sound insulation layer. A 50mm thick industrial felt is wrapped around the drum mill's wall, and 1.smm thick steel plate is used as the protection surface. It is bolted to the outer wall of the drum, and the actual sound insulation value is about 12dB (A). If the two ends of the drum are also treated in the same way, the joints wrapped on the drum wall are sealed, and the sound insulation effect may be improved.

6. Damping sound insulation layer Wrap the barrel of the ball mill with a sound insulation material to reduce the cylinder noise. This method can generally reduce 5-10dBA, the effect is not ideal.