Because of the small elastic modulus and large internal resistance of polyurethane materials, the use of ultrafine vertical mill can effectively reduce noise.
According to a French data, the noise of polyurethane sieve plate can be 15-20db (a) lower than that of ordinary metal sieve plate under the same excitation condition. But the noise of other parts such as side plates has not been reduced, in practice, the overall noise of ultrafine vertical mill can be reduced by 5dB (a).
The plate structure of screen box side plate and back plate are all made of sheet welded or riveted. These large area plates will radiate strong noise under the action of excitation force. The radiation noise of the plate surface is proportional to the square of the plate vibration speed. Therefore, the damping material can be applied to the plate surface to achieve the purpose of noise reduction.