Traditional ventilation ducts are an adjunct to a building and are rarely studied.  With the development of The Times, the function of air duct is gradually increasing, and the ventilation duct is not satisfied with the requirements of basic ventilation intensity, but also has the functions of fire prevention, energy saving and environmental protection, easy cleaning and so on.  However, the most important thing is no noise!

 Since the 1940s, China began to use ventilation pipes for the textile industry, in order to improve the quality of spinning fabric, so that the workshop environment to maintain and transport specific temperature and temperature air.  And that's when the battle against noise begins in earnest.

 What is noise?

 Answer: noise is a kind of sound that causes people to be agitated, or is too loud and harmful to human health.

 From the point of view of environmental protection: all the sound that interferes with people's normal rest, study and work, as well as the sound that interferes with people's listening, belong to noise.

 From the point of view of physics: noise is the sound produced when the vocal body does irregular vibration.

 How does a duct make noise?

 Answer: The main source of duct noise comes from the fan. The fan produces vibration in operation and transmits it to the room through the duct. The second is the duct vibration caused by friction with the wall of the duct in the process of air circulation, eddy current vibration caused by air friction in the duct, vibration between the duct, and vibration caused by the imbalance of internal and external pressure.

 How can we solve the noise generated by air duct?

 Answer :(1) material selection ,air duct with better suction effect is selected. If the suction effect of iron duct is poor, air duct lining can be installed to reduce noise.

 (2) The wind speed is appropriately selected. The higher the wind speed, the greater the noise, the higher the wind speed will cause the vibration of the air duct. The muffler should be set at the elbow tee reducer.

 (3) During installation, air ducts should be reinforced as required to reduce the vibration of air ducts.

 (4) Silenced cotton felt should be placed at the joint of air duct.

 As a new environmental protection building material, Uetersen formaldehyde-free composite glass fiber duct is a central air conditioning ventilation duct made of high volume weight formaldehyde-free glass wool board as the base material, the outer surface of which is a layer of composite aluminum foil, and the inner surface of which is a layer of anti-corrosion and moisture-proof composite glass fiber felt.

 Lining: non-toxic harmless polymer nano coating and composite glass fiber felt, has good fire prevention, waterproof, moistureproof, mouldproof, bacteriostasis, corrosion resistance, prevent of fibers, and other functions, accord with the requirement of air conditioning and ventilation system, effectively guarantee the duct pipe internally and indoor air clean and fresh, long-term exposure to make human body produce no bad reaction.

 Outer layer: composite glass fiber air duct surface layer material with imported special aluminum foil veneer, strong toughness, good air tightness, and formaldehyde-free glass wool board composite fully, effectively reduce the energy loss, while ensuring the overall robustness and beautiful appearance of the air duct.

 Middle layer: using uetersen formaldehyde-free environment-friendly glass wool board, density 80 kg/cubic meter, with sound absorption, sound insulation, noise reduction, vibration reduction, anti-corrosion, heat preservation, heat insulation and other functions, in the operation of the air conditioning system, can effectively reduce the middle and high frequency noise, with good heat preservation performance.

 Air duct as environmental protection building products, is a very important existence, with the improvement of people's requirements for quality of life, the use of air duct will be more and more widely.  At present, Uetersen formaldehyde-free environmental glass fiber duct has been widely used in transportation space, medical space, education space, commercial space, office space and so on.