Latest Duct Manufacturing Standards 2026 | Process & Technical Requirements
1. What is an Air Duct?
An air duct is a system used to transport air in facilities such as factories, buildings, and commercial centers. It enables effective air circulation, fresh air supply, and exhaust air removal. The duct system plays a crucial role in HVAC (Heating, Ventilation, and Air Conditioning).
2. Common Air Duct Manufacturing Standards
To ensure quality, durability, and operational efficiency, air ducts must comply with international and Vietnamese standards such as:
2.1 SMACNA Standard
This is the most widely used standard in the duct industry. It specifies:
- Sheet metal thickness based on duct size
- Reinforcement (stiffeners)
- Connection methods (TDC, TDF flanges)
Widely applied in factories and high-rise buildings.
2.2 DW/144 Standard (UK)
Applicable to low, medium, and high-pressure duct systems, with strict requirements on:
- Air tightness
- Leakage testing
- Material quality
2.3 ISO Standards
Related to quality management systems:
- ISO 9001 (Quality Management)
- ISO 14001 (Environmental Management)
Ensure duct manufacturing processes meet international standards.
2.4 Vietnamese Standards (TCVN)
Applied to ventilation and air conditioning systems:
- Design
- Installation
- Inspection and acceptance
3. Duct Manufacturing Materials
Common materials used in duct production include:
- Galvanized steel (GI): most common
- Stainless steel (Inox): high corrosion resistance
- Aluminum: lightweight and easy to install
Requirements:
- Smooth surface, no rust
- Thickness meets standards (0.5mm – 1.2mm depending on size)
4. Standard Duct Manufacturing Process
A standard duct manufacturing process includes:
Step 1: Design & Drawing Breakdown
- Based on HVAC system
- Optimize airflow and pressure
Step 2: CNC Cutting
- Ensure high precision
- Minimize errors
Step 3: Forming
- Bending, folding, assembling
- Creating rectangular or round ducts
Step 4: Flange Fabrication
- TDF/TDC flanges
- Ensure strong connections
Step 5: Reinforcement
- V-shaped ribs or stiffeners
- Prevent deformation
Step 6: Quality Inspection
- Air tightness
- Dimensions
- Mechanical strength
5. Key Technical Requirements
During duct manufacturing, it is essential to ensure:
- High air tightness (to prevent airflow loss)
- Smooth surface to reduce friction
- No leakage at joints
- Ability to withstand operating pressure
- Sound insulation and thermal insulation (if required)
6. Benefits of Standard-Compliant Duct Manufacturing
- Improve HVAC system efficiency
- Save energy
- Reduce maintenance costs
- Extend building lifespan
- Ensure air quality
