How to reduce noise in pneumatic conveying
? ? The significance and control methods of reducing noisepneumatic tube conveyor There are various forms of aerodynamic machinery that require different forms, capacities, and pressures for conveying capacity and usage. Such as Roots blower, centrifugal fan, reciprocating compressor, etc. These aerodynamic machinery generate strong noise during operation, which is the main source of noise in pneumatic conveying systems. The peak noise can reach 100-125dB, seriously polluting the surrounding environment and endangering the health of workers. Therefore, effective control measures should be taken to eliminate the hazards of aerodynamic mechanical noise.
? ? The noise generated by aerodynamic machinery during operation can be divided into three types: aerodynamic noise, mechanical noise, and electromagnetic noise. Aerodynamic noise refers to the noise radiated due to gas loosening; Mechanical noise refers to the noise radiated by the looseness caused by friction, collision, and unbalanced operation of the transmission device and the fan; Electromagnetic noise refers to the noise radiated by magnetostriction caused by the operation of an electric motor.
? ? Among these three types of noise, aerodynamic noise has the highest intensity. Practice has shown that aerodynamic noise is generally 10-20 dB stronger than mechanical noise. Therefore, this type of noise poses the greatest harm, and controlling it is an urgent task.
? ? In order to effectively control noise, it is necessary to understand through which pathways the aerodynamic mechanical noise is radiated to the surrounding environment? The magnitude and spectral characteristics of noise generated by different models of aerodynamic machinery are different. However, in summary, there are three ways in which they radiate noise outward:
? ? 1) Radiate noise into the space through the intake and exhaust ports of the fan.
? ? 2) Radiate noise into space through the casing and pipe walls.
? ? 3) Radiate noise through the space between basic vibrations.
? ? The first two are called airborne sound, and the latter is called solid sound.
? ? Understanding the sound source is the key to controlling the noise of pneumatic conveying. Corresponding control measures must be taken for the different ways in which aerodynamic mechanical noise spreads outward. The usual methods include mufflers, sound insulation, damping, sound absorption and radiation, and vibration isolation.
