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Spiral Duct and Fittings

The Spiral Duct are widely used in HVAC air distribution systems, known for their excellent strength, aesthetic appearance, and airflow efficiency.
Formed from continuous strips of galvanized steel into a spiral seam, these ducts provide superior rigidity, low leakage, and a clean, professional finish ideal for both exposed and concealed installations.

Spiral ducts are suitable for commercial, industrial, and public facilities where efficient air movement, space optimization, and long service life are required. Fittings such as elbows, reducers, and joints ensure smooth airflow transitions throughout the duct network.

Key Specifications

  • Material: Galvanized Steel / Stainless Steel / Aluminum

  • Diameter: 100 – 1600 mm (customizable)

  • Thickness: 0.5–1.2 mm

  • Standard: SMACNA / DW144 / ISO 9001

  • Connection: Slip Joint / Coupling / Flange System

Key Features

Smooth Airflow & Low Leakage

The spiral seam design ensures uniform airflow and minimizes pressure loss, delivering better energy performance than rectangular ducts.

High Structural Strength

The continuous spiral seam construction provides excellent rigidity, allowing longer unsupported duct runs with fewer hangers.

Quick Installation

Pre-fabricated lengths and easy-to-use fittings reduce on-site labor time and simplify system assembly.

Versatile Design Options

Available in multiple diameters and materials, with compatible fittings such as elbows, reducers, and take-offs for complete air duct systems.

Technical Specifications

MaterialGalvanized Steel (G90 / DX51D+Z), Stainless Steel, or Aluminum
Diameter Range100 – 1600 mm
Thickness0.5 – 1.2 mm
LengthStandard 3 m or 4 m sections
Connection TypeSlip Joint, Coupling, or Flange System
StandardsSMACNA / DW144 / ISO 9001
Surface FinishZinc Coated / Powder Coated / Painted
ApplicationAir Supply, Return Air, Exhaust, and Fresh Air Systems

Applications

BromingHvac
Spiral ducts and fittings are used in a wide range of HVAC systems that demand efficient airflow and space-saving installation. Typical applications include:
Office buildings and commercial centers
Industrial ventilation and process exhaust
Underground parking and tunnel systems
Airports, metro stations, and transport terminals
Public buildings, auditoriums, and warehouses

Material & Manufacturing Process

Spiral ducts are produced using advanced automatic forming machines that roll galvanized steel into a continuous spiral seam, ensuring consistent diameter and perfect roundness.
Coil Feeding: Prime galvanized steel coil is loaded for continuous operation.
Forming: The metal strip is shaped and locked into a spiral seam, creating strong, airtight ducts.
Cutting: Each section is cut to the required length with clean edges.
Fittings Fabrication: Elbows, reducers, and branches are produced using CNC plasma cutters for precise dimensions.
Testing: Air leakage and dimensional checks are performed before packaging.
BromingHvac