Features of Aosun Acoustic Flexible Duct
- Multi-layer sound absorption reduces HVAC airflow noise effectively
- Its flexibility makes it fit complex duct layouts and tight installation spaces easily.
- It is easy to Install because of lightweight, so don’t need special tools required for cutting and fixing.
- Aosun offers ODM/OED customization, including diameter, length and insulation thickness.
Aosun | Professional Acoustic Flexible Duct Manufacturer in China
Aosun is a leading Chinese manufacturer of acoustic flexible duct. Our acoustic flexible duct is widely used in HVAC systems and various noise-sensitive ventilation systems. It can effectively reduce airflow noise and equipment vibration, create a quiet environment, suppress noise transmission, and improve indoor comfort. Our acoustic flexible duct is made of high-quality multi-layer materials which has excellent sound absorption, durability, and airtightness performance. It can be used in temperatures ranging from -30°C to 140°C. Its flexible and lightweight structure makes it convenient for transportation and installation, especially suitable for complex and tight layout scenarios. The diameter of the acoustic flexible ducts we produce ranges from 4 to 18 inches, which can meet various ventilation and noise reduction requirements. It is suitable for home, commerce, industry, and professional noise-sensitive areas such as hospitals and recording studios. In addition, our acoustic flexible duct has passed international certifications such as SAA, CE, ISO, and RoHS, ensuring that every product you purchase is of high quality.
It is the mainstream conventional model for residential and small commercial projects. It is suitable for conventional HVAC ventilation layout,
The outer layer of aluminum foil is heat-resistant and suitable for high-temperature and harsh ventilation environments that require fire resistance
The PVC outer layer is waterproof and moisture-proof, it is suitable for damp and high-humidity environments such as basements and bathrooms.
It has the dual performance of professional noise reduction and thermal insulation, which is suitable for central air conditioning cooling and warm air supply
What is Acoustic Flexible Duct?
Acoustic flexible duct is a multi-layer sound-absorbing structure duct designed for HAVC system . It mainly used to reduce the air flow noise and equipment vibration noise in the ventilation system. Different from ordinary flexible duct, acoustic flexible duct core purpose is sound attenuation rather than thermal insulation. It has solved the noise pollution problem caused by the ventilation system and is widely used in scenarios with high requirements for quietness.
Structure of Acoustic Flexible Duct
Acoustic flexible duct adopts a three-layer integrated structure, which can effectively reduce noise without affecting the airflow. Its noise reduction principle is to absorb noise rather than reflect noise.
The inner material is aluminium foil, which is covered with a dense tiny holes. It is supported by a spiral structure of high-strength steel wires, which enables air flow smoothly and guides noise to the sound-absorbing layer.
The sound-absorbing layer is mainly composed of glass wool or polyester fibers, which can completely absorb the noise generated by air flow and equipment vibration, thereby reducing the spread of noise to the surrounding environment.
The outermost layer is made of aluminium foil combined with PE/PVC material, which has excellent tear resistance and sealing properties. It can effectively protect the internal sound-absorbing layer from being eroded by external moisture and dust.
Applications of Acoustic Flexible Duct
Residential HVAC Systems
Used in residential HVAC systems where low-noise airflow is required for bedrooms, living rooms, and renovation projects. It can solve the buzzing sounds caused by air conditioners, ventilation equipment fans and air flow, avoid the disturbance of noise to rest and work, and create a quiet and comfortable home environment. It is also suitable for bathroom and kitchen ventilation systems that need to reduce exhaust noise. You can use the sound attenuator duct for your residential HVAC system.
Commercial Buildings
Sound attenuator duct is ideal for offices, hotels, shopping malls and fine restaurants. When you use it to reduce the noise of central air conditioning and ventilation systems, it can ensure employees work efficiently, customers enjoy a comfortable experience, and improves the overall quality of the commercial space.
Noise-Sensitive Areas
In many scenarios where noise sensitivity is required, you can use sound attenuator ducts, such as in hospitals, libraries, study rooms, recording studios, etc. These areas have extremely strict noise control requirements. Ordinary ventilation ducts would transmit air flow and equipment noise, causing interference to the environment. Using low-noise ventilation ducts can minimize the noise transmission of the ventilation duct system, ensuring that these areas remain quiet.
Industrial Ventilation
Factories usually require large air volume exhaust, which means that the generated airflow noise will also be louder. In places such as factory workshops, equipment rooms, and warehouses where noise control of equipment is needed, it can significantly reduce the noise produced by industrial exhaust fans and ventilation equipment, improve the working environment of employees, and comply with environmental noise standards.
How to Choose Acoustic Flexible Duct?
Noise Reduction Requirement
If the required noise reduction is between 15 and 20 decibels, you should choose a insulation layer thickness ranging from 15 to 20 millimeters. If the noise reduction exceeds 20 decibels, you should choose an insulation layer that is 25 millimeters or thicker. 1m duct can reduce noise by about 20dB with 25mm glass wool.
Airflow and Diameter
You need to select the diameter of the duct based on the airflow volume. If the diameter is too small, it will cause excessive wind resistance and increase noise due to air compression. If the diameter is too large, it will cause material waste and slow down the air flow speed, thereby affecting the overall ventilation effect. For example, an airflow of 100 CFM is suitable for a duct with a diameter of 100 millimeters. An airflow of 400 CFM is suitable for a duct with a diameter of 150 millimeters.
Duct Length and Layout
Long duct systems can increase airflow resistance and amplify transmitted noise if ordinary ducts are used. Because when the airflow passes through a long duct, the noise generated by the friction between the airflow and the duct and the vibration of the air duct will continuously accumulate and amplify. Ordinary ducts cannot effectively control the spread of this noise. At this point, you can choose acoustic flexible duct. For complex duct layouts, flexible ducts have high flexibility and can be easily bent and arranged.
Installation Environment
In high-temperature conditions, we recommend that you choose the noise-reducing flexible pipe with an aluminum foil outer layer. Aluminum foil material has excellent high-temperature resistance and can stably withstand a temperature range of -30℃ to 140℃. In damp environments such as bathrooms and basements, you can choose the noise-reducing flexible pipe with a PVC outer layer. PVC material has excellent moisture-proof and waterproof properties, which can effectively prevent external damp air and water vapor. In highly corrosive industrial environments, it is necessary to customize the anti-corrosion outer layer material.
Installation Notes of Acoustic Flexible Duct
Avoid excessive bending: The minimum bending radius should not be less than 1.5 times the pipe diameter to prevent damage to the sound-absorbing layer and to ensure the noise reduction effect and air flow.
Keep straight: During installation, the pipe should be kept as straight as possible to avoid dead bends or collapses, which can cause air blockage and increased noise.
Seal connections: Use aluminum foil tape and clamps to seal the connection between the pipe and the fan outlet to prevent air leakage and noise leakage.
Support spacing: If the length of the noise reduction flexible duct is long, a hanger should be installed every 1.5 meters to prevent the flexible duct from falling.
Why Choose Aosun Acoustic Flexible Duct?
Aosun acoustic flexible duct is made of high-quality metal and glass wool. We have our own factory and production line, which can ensure a stable delivery period to guarantee that your project can proceed on schedule. Moreover, we offer OEM/ODM services. You can customize the length, diameter, thickness of the sound-absorbing layer, and outer material of the noise-reducing flexible duct according to your needs. The Aosun acoustic flexible duct strictly follows international standards and has passed SAA, CE, and RoSH international certifications to ensure that every product undergoes strict quality inspection. Aosun has complete after-sales service and can provide online installation guidance and maintenance suggestions for you. If there is any quality problem, aosun supports the return and replacement service.
The core sound-absorbing materials commonly used in silenced flexible ducts are mainly glass wool and high-density polyester fibers. Both materials have a porous sound-absorbing structure and are highly effective in absorbing air flow noise and fan resonance noise. Moreover, they have high heat resistance and are not prone to aging or deformation. They are mainstream filling materials recognized in the industry for their stable noise reduction effect.
The main difference is their function. The core function of acoustic flexible duct is to reduce noise and reduce the noise generated during air transportation. The core function of the insulation hose is insulation, reducing the loss of heat when conveying hot and cold air. Some products have both of these functions, but their designs and applications are completely different. When choosing, you should base your decision on the primary requirements of the project.
The noise reduction effect of the silencing flexible duct is not a fixed value. It is mainly influenced by the length of the duct, the thickness of the sound-absorbing layer, and the actual air volume. Generally, it can reduce the noise by 10-20 decibels. In addition, system designs such as pipeline layout, the number of elbows, and installation sealing techniques will also affect the final noise reduction effect.
Yes, the length of the duct directly affects the noise reduction effect. the more obvious the noise reduction effect will be, and the better the silent performance will be. However, the longer the air duct is not the better. The increase of the length will increase the air resistance of the air duct and reduce the ventilation air volume and system operation efficiency. You need to consider both noise reduction and duct resistance when selecting the model.
Generally speaking, the thicker the sound-absorbing layer, the better the noise reduction effect of the sound-absorbing flexible duct. However, as the thickness increases, the cost of raw materials and production will also rise. When you choose a model, do not blindly pursue extremely thick specifications. Based on the noise level of the project, the budget and the installation space to choose an appropriate thickness can balance the noise reduction effect and cost performance.
The silencing flexible duct can be adapted to large air volume ventilation systems, but you must choose a larger pipe diameter. In high-speed wind conditions, if the pipe diameter is too small, it will easily increase noise and wind pressure loss, and also weaken the overall ventilation efficiency. By matching the appropriate large-diameter model, it can not only meet the demand for large air volume transportation, but also maintain the noise reduction performance of the duct, while controlling the wind pressure loss within a reasonable range.
The silencing flexible duct is highly suitable for long-distance duct laying. The longer the pipe, the more its multi-layer sound-absorbing structure can continuously reduce noise, and the more prominent the silent advantage will be. But you need to pay attention to the long distance use will increase the overall wind resistance, easy to affect the air volume and wind pressure. When selecting, we recommend that you appropriately increase the pipe diameter to balance the noise reduction effect and ventilation efficiency.
First, you need to measure the size according to the length of the on-site pipeline, and then cut the air duct with scissors or an art knife. Place the two ends of the air duct over the fan and the air outlet respectively, wrap them with aluminum foil tape for sealing, and then fix them with clamps. During installation, try to lay it in a straight line and avoid squeezing the air duct. After completion, check whether the ventilation is smooth and if there are any abnormal noises.
Acoustic flexible duct requires minimal maintenance. You just need to conduct a simple inspection at regular intervals to check if the pipelines are damaged, if the interfaces are leaking air, and if the outer layer is damp or aged. Keep the inlet and outlet of the duct unobstructed and avoid the accumulation of debris. The noise reduction performance and ventilation efficiency of the air duct can be maintained for a long time without frequent disassembly and cleaning.
There is no fixed standard for the service life of sound-absorbing flexible air ducts. It mainly depends on the temperature and humidity of the installation environment, ventilation conditions, and daily maintenance. Under normal indoor conditions, it can operate stably for 8 to 15 years. However, in harsh conditions such as high humidity, high temperature, or high dust content, the aging process will accelerate and the service life will be shortened accordingly.
