Introduction to Flexible Sleeves in Spiral Duct Systems

In HVAC systems, it is often necessary to convert round ducts to rectangular or other shapes to align with architectural limitations or installation conditions. The spiral duct flexible sleeve takes on this task and provides the possibility of transferring airflow from a round duct to a desired shape in a principled and standard manner.
In addition to changing the duct shape, sleeves play an important role in maintaining uniform airflow, reducing pressure drop, and preventing noise generation. Proper sleeve design ensures that airflow reaches its destination without disruption and with high efficiency.

Applications of Spiral Duct Flexible Sleeves

Sleeves are used in various parts of the ventilation system:

• Converting round ducts to rectangular or square ducts
• Connecting ducts to grilles or ceiling and wall diffusers
• Harmonizing the ventilation network with architectural limitations
• Guiding airflow to different spaces with minimal pressure drop
• Use in industrial projects with large and diverse ducts

In large and complex projects, sleeves allow engineers and installers to execute the ventilation network with minimal changes to the building structure and maximum efficiency.

Types of Spiral Duct Flexible Sleeves

Sleeves are divided into several categories based on application and duct shape:

Round to Rectangular Sleeve
This type of sleeve is designed to convert a round duct to a rectangular duct and has the most application in ventilation systems.
Advantages:

• Adapting the duct to ceiling and wall diffusers
• Smooth and uniform airflow
• Reduced pressure drop

Round to Square Sleeve
In this model, the round duct is converted to a square duct and is used in projects that require square ducts or ducts with standard dimensions.

Custom Dimension Sleeves
Some projects require sleeves with specific sizes and shapes to align with architectural limitations or ventilation equipment. Kian Fan provides the possibility to manufacture sleeves according to project drawings and requirements.

Advantages of Using Standard Sleeves

Using standard and high-quality sleeves offers numerous benefits:

• Maintaining airflow uniformity
• Reducing system pressure drop
• Preventing noise generation and air turbulence
• Complete compatibility with system engineering design
• Reducing fan energy consumption
• Fast and easy installation

These benefits, especially in large and industrial projects, lead to increased system productivity and reduced maintenance costs.

Material and Composition of Spiral Duct Flexible Sleeves

Sleeves are usually manufactured from the following materials:

• Galvanized steel sheet (most common and cost-effective option)
• Stainless steel sheet (for special environments and corrosion resistance)
• Aluminum sheet (lightweight and usable in confined spaces)

Galvanized sheet is the primary choice for most projects due to its high durability, corrosion resistance, and suitable price.

Important Considerations in Sleeve Design and Installation

To use sleeves optimally, attention must be paid to the following:

• Precise matching of the round duct diameter and rectangular or square duct dimensions
• Angle and length of the sleeve to reduce pressure drop
• Manufacturing quality and sealing
• Compatibility with the overall ventilation system and other fittings
• Project application type (residential, commercial, or industrial)

Choosing the appropriate sleeve plays an important role in the overall performance of the system and prevents execution and energy issues.

Application of Sleeves in Different Projects

Sleeves are used in various types of projects:

• Residential buildings and office complexes
• Commercial and retail centers
• Hospitals and medical centers
• Factories, sheds, and industrial spaces
• Conference halls and public centers

In each of these projects, sleeves allow engineers and installers to guide airflow with minimal pressure drop and maximum efficiency.

Conclusion

The spiral duct flexible sleeve is one of the vital connections in HVAC systems responsible for converting round ducts to rectangular or other forms. Using standard and high-quality sleeves increases system efficiency, reduces pressure drop, and ensures uniform airflow. Kian Fan offers various types of spiral duct flexible sleeves with high quality and in accordance with modern standards to professionally meet the needs of different ventilation projects.