Galvanized Steel Pipes — Standard Sizes

GI (galvanized iron) pipes follow standard diameter increments including 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and 16 inches for common industrial applications. For heavy-duty or large-scale installations, diameters exceeding 16 inches up to 80 inches and larger are also manufactured to order.

Galvanized steel pipe for industrial ductwork is typically referenced by its nominal inside diameter (ID), which corresponds to the actual airflow cross-section. The outside diameter will be slightly larger due to wall thickness. Always confirm ID versus OD with your supplier when ordering to ensure compatibility with fittings and system components.

Standard steel pipe diameters for industrial duct applications range from 3 inches to 16 inches in common increments, with gage specifications tied to diameter size. Larger custom sizes from 17 inches to over 80 inches are available for heavy industrial and pneumatic conveying systems. Confirm gage and wall thickness requirements based on application pressure and temperature.

Duct Incorporated offers pipes in galvanized steel, galvaneal, stainless steel 304, stainless steel 316, and aluminum. Each material suits different environments: galvanized for general use, stainless 304/316 for corrosive or high-moisture conditions, aluminum for lightweight applications, and galvaneal where paint adhesion or welding is required.

Yes. In addition to standard diameters from 3 to 80-plus inches, Duct Incorporated provides custom fabrication services for specialized industrial requirements. Custom sizing, non-standard lengths, and specialized configurations are available. Contact the team with your project specifications to receive a tailored quote and fabrication timeline.

Galvanized steel pipes are widely used in industrial dust collection systems, HVAC and ventilation distribution, pneumatic material conveying, fume extraction, and exhaust systems. Their structural integrity, corrosion resistance, and broad diameter range make them suitable for manufacturing plants, warehouses, processing facilities, and commercial building mechanical systems.