Double Wall Spiral Pipe And Fittings


Pro-Fab Sheet Metal double-wall, insulated duct and fittings provide exceptional noise and thermal control in air handling systems. They are constructed of a solid sheet metal outer pressure shell and a sheet metal inner liner with a layer of insulation sandwiched between.

DUCT CONSTRUCTION Our standard double-wall duct and fittings have galvanized sheet metal outer walls and a layer of fiberglass insulation surrounding the inner liner. The duct has a perforated metal inner liner, while standard fittings have a solid metal inner liner. Options include other thicknesses and types of insulation, stainless steel and aluminum outer walls, and specification of solid-wall or perforated-wall inner liners as nonstandard items.

These options and the numerous sheet metal gauges that are available enable Pro-Fab Sheet Metal to provide double-wall duct and fittings for a wide range of environments, including hospitals, laboratories, food and pharmaceutical plants, and corrosive industrial areas.

Condensation can form on the outside of duct systems that convey cold air, especially at times during the summer when the ambient relative humidity is high and a large temperature differential exists between the inside and outside of the duct system. Our standard 1-inch-thick insulation prevents external condensation.

Double-wall duct and fittings are ideal for use in architecturally exposed applications. The sheet metal outer shell has a uniform, finished appearance, and it can be painted to match or complement its surroundings. Externally insulated duct systems have unattractive surfaces that are susceptible to damage and difficult to paint.

Pro-Fab Sheet Metal double-wall, round duct is fabricated to exacting tolerances that make it easy to assemble and essentially leak free. This insulated duct provides excellent acoustical and thermal control with the efficient airflow performance of single-wall round duct.

Our spiral lockseam duct can be fabricated in lengths of 10 feet or greater. These longer sections of duct mean fewer joints and faster installation.

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