The elevator well sound-absorbing board is specially designed for elevator hoistway and engine room, and sound insulation material is produced. The core material is yellow glass wool fiber. Centrifugal glass wool is an acoustic material that has been widely used all over the world and has been proved to have excellent sound absorption. Performance, and excellent fire performance, its surface composite sound-absorbing particles. The main role is to enhance the sound absorption effect, and more convenient installation. The shape of the lift well sound-absorbing board is concave-convex. This special structure increases the effective sound absorption area and at the same time changes the sound reflection effect. The noise reduction coefficient is NRC=0.75. It is mainly applicable to elevator shafts, elevator machine rooms, and air-conditioning equipment rooms. Noise absorption and noise reduction in various types of specific structures. And it is non-toxic and harmless. It is a real green sound-absorbing decorative board.
Ladder sound-absorbing cotton fluffy and interlaced inside fibers, there are a lot of tiny pores, is a typical porous sound-absorbing material, with good sound absorption properties. Centrifugal glass wool can be made into wall panels, ceilings, space acoustic absorbers, etc., can absorb a large number of acoustic energy in the room, reduce reverberation time and reduce indoor noise.
Sound absorption principle
Elevator sound-absorbing cotton is a porous sound-absorbing material with good sound absorption properties. The reason why centrifugal glass wool can absorb sound is not due to rough surface, but because it has a large number of tiny pores and holes that communicate with each other. When sound waves are incident on the centrifugal glass wool, sound waves can enter the interior of the material along the pores, causing vibration of the air molecules in the voids. Due to the viscous resistance of air and the friction between the air molecules and the pore walls, acoustic energy is converted into heat energy and lost.
The sound absorption performance of elevator sound-absorbing cotton also has a close relationship with installation conditions. When there is an air layer behind the elevator well sound-absorbing cotton board, the sound absorption effect of the sound-absorbing cotton elevator shaft with the same thickness and no air layer is similar. In particular, the sound absorption performance of medium and low frequencies will be greatly improved compared with the fact that the material is actually attached to the hard bottom surface. The sound absorption coefficient will increase with the increase of the thickness of the air layer, but the effect will not be obvious after increasing to a certain value. Glass wools with different bulk density are stacked together to form a gradually increasing bulk density and a greater sound absorption effect can be obtained.
Ladder sound-absorbing cotton fluffy and interlaced inside fibers, there are a lot of tiny pores, is a typical porous sound-absorbing material, with good sound absorption properties. Centrifugal glass wool can be made into wall panels, ceilings, space acoustic absorbers, etc., can absorb a large number of acoustic energy in the room, reduce reverberation time and reduce indoor noise.
Sound absorption principle
Elevator sound-absorbing cotton is a porous sound-absorbing material with good sound absorption properties. The reason why centrifugal glass wool can absorb sound is not due to rough surface, but because it has a large number of tiny pores and holes that communicate with each other. When sound waves are incident on the centrifugal glass wool, sound waves can enter the interior of the material along the pores, causing vibration of the air molecules in the voids. Due to the viscous resistance of air and the friction between the air molecules and the pore walls, acoustic energy is converted into heat energy and lost.
The sound absorption performance of elevator sound-absorbing cotton also has a close relationship with installation conditions. When there is an air layer behind the elevator well sound-absorbing cotton board, the sound absorption effect of the sound-absorbing cotton elevator shaft with the same thickness and no air layer is similar. In particular, the sound absorption performance of medium and low frequencies will be greatly improved compared with the fact that the material is actually attached to the hard bottom surface. The sound absorption coefficient will increase with the increase of the thickness of the air layer, but the effect will not be obvious after increasing to a certain value. Glass wools with different bulk density are stacked together to form a gradually increasing bulk density and a greater sound absorption effect can be obtained.
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