Most of the fans used in industry are centrifugal fans, which is a common fan model. So, how can the centrifugal fan be soundproof and noise-canceling? Centrifugal fans usually have a large volume and need to use sound insulation covers for noise control, which is also the reason why many centrifugal fans are locked in the covers.
I. Noise source of centrifugal fan
Centrifugal fan noise sources can be divided into three types: air flow noise from air inlet and air outlets, noise and vibration from fan unit, noise and vibration from fan pipe. Among them, the noise of fan unit, inlet and exhaust fan can be solved by sound insulation cover. It can be said that as long as the sound insulation cover is used well, the noise of centrifugal fan can be solved by more than half.
II. Centrifugal fan sound insulation cover
1. Volume requirements of sound insulation cover
The sound insulation cover of centrifugal fan needs to be customized. The customized sound insulation cover is similar to the body of centrifugal fan. The reason why it is made is to save materials and reduce the cost and price of the sound insulation cover. The sound insulation cover is not completely enclosed in it, leaving air vents and exhaust ports for the centrifugal fan to operate, and also installing soundproof door, windows and other devices to overhaul the centrifugal fan.
2. Sound insulation cover plate material
The material of the sound insulation cover plate is related to its sound insulation capacity, and is generally selected for the noise spectrum. The sound insulation cover plate belongs to multi-layer acoustic construction, including outer layer, middle layer and lining. Each layer uses different materials. For example, the thickness of the outer plate is 2-3mm, and there are lead plate, steel plate, aluminum plate and other materials to choose from. The most used is stainless steel plate; The middle is damping layer; The lining is porous sound absorbing material. The acoustic construction sound insulation cover plate can make the internal noise impenetrable, and the noise reduction is about 30 decibels.
3. Installation of sound insulation cover
The sound insulation cover is detachable and easy to transport. After it is made according to the design scheme in the factory, it can be installed after being transported to the destination. Attention should also be paid to the installation of the sound insulation cover, especially the soft connection between the sound insulation cover body and the Machine, otherwise the vibration and noise of the equipment can easily spread out through the sound insulation cover.
III. Noise control method of centrifugal fan
After the centrifugal fan is installed with sound insulation cover, its noise can be reduced by more than half, which is enough to meet the noise reduction requirements of most factories. The fan pipes in some factories also emit noise. These noise insulation covers cannot be solved and separate noise control methods need to be used. The specific measure is to fix the fan pipe, and then carry out sound insulation and dressing; The support and hanger of the fan pipe are replaced with elastic devices. Various sound insulation measures to reduce the noise and vibration of centrifugal fan pipes.
