Abstract: A glass fiber duct liner, for lining sheet metal ducts in air conditioning, heating and ventilating systems, includes a flexible blanket of biosoluble glass fibers exhibiting a biodisolution rate in excess of 150 ng/cm2/hr. The glass fibers of the blanket are bonded together at their points of intersection by a colorless, formaldehyde-free, thermosetting, acrylic acid-based latex binder resin. A major surface of the blanket, adapted to be an interior surface of the blanket over which an airstream is to be conveyed by a duct system, is coated with a white acrylic latex water and dirt repellant coating that contains an antimicrobial agent.

Abstract: Ducts are formed from rigid or semi-rigid insulation boards by forming a plurality of longitudinally extending, spaced apart, parallel kerfs in a first major surface of each of the insulation boards which is adapted to be the interior surface of the duct. When the insulation board is formed into a duct of the preselected dimensions, the shoulders of the kerfs adjoining the interior surface of the duct abut and, preferably, the insulation material in the shoulders of the kerfs is compressed. The flexibility of the insulation boards, in the direction of the widths of the insulation boards, is controlled by increasing the depths and/or the widths of the kerts and/or decreasing the spacing between the kerfs to make the insulation board more flexible and by decreasing the depths and/or the widths of the kerfs and/or increasing the spacing between the kerfs to make the insulation board less flexible.

Abstract: Ducts are formed from rigid or semi-rigid insulation boards by forming a plurality of longitudinally extending, spaced apart, parallel kerfs in a first major surface of each of the insulation boards which is adapted to be the interior surface of the duct. When the insulation board is formed into a duct of the preselected dimensions, the shoulders of the kerfs adjoining the interior surface of the duct abut and, preferably, the insulation material in the shoulders of the kerfs is compressed. The flexibility of the insulation boards, in the direction of the widths of the insulation boards, is controlled by increasing the depths and/or the widths of the kerfs and/or decreasing the spacing between the kerfs to make the insulation board more flexible and by decreasing the depths and/or the widths of the kerfs and/or increasing the spacing between the kerfs to make the insulation board less flexible.

Abstract: Ducts are formed from rigid or semi-rigid insulation boards by forming a plurality of longitudinally extending, spaced apart, parallel kerfs in a first major surface of each of the insulation boards which is adapted to be the interior surface of the duct. When the insulation board is formed into a duct of the preselected dimensions, the shoulders of the kerfs adjoining the interior surface of the duct abut and, preferably, the insulation material in the shoulders of the kerfs is compressed. The flexibility of the insulation boards, in the direction of the widths of the insulation boards, is controlled by increasing the depths and/or the widths of the kerfs and/or decreasing the spacing between the kerfs to make the insulation board more flexible and by decreasing the depths and/or the widths of the kerfs and/or increasing the spacing between the kerfs to make the insulation board less flexible.

Abstract: A duct for gas flow applications is provided with a replaceable insulating duct liner that can be axially inserted into and removed from a tubular shell of the duct. Preferably, the replaceable insulating duct liners comprise fibrous and/or cellular insulation materials. Duct systems using duct sections with replaceable insulating duct liners can be maintained by removing duct sections from the system; removing the replaceable insulating duct liners from the duct sections; inserting new replaceable insulating duct liners into the duct sections; and replacing the duct sections into the duct system.

Abstract: A glass fiber duct board has longitudinally extending, spaced-apart grooves in a major surface that facilitate the folding of the duct board into an air duct. The major surface, including the grooves, is coated with a polymeric latex coating to encapsulate glass fibers and dust within the surface of the duct board. The polymeric latex coating is applied to the surfaces of the grooves as a foam by application nozzles located downstream of groove cutting tools. The polymeric latex coating applied by the nozzles is distributed over the surfaces of the grooves and set to a predetermined thickness by wiper blades, located downstream of the nozzles, which have edge configurations complementary to the transverse configurations of the grooves being coated.

Abstract: Molded fibrous workpieces of various cross sectional configurations are coated with a polymeric latex foam coating material to encapsulate fibers and dust within the exterior surfaces of the workpieces. The foam coating is applied by passing the workpieces through a coating chamber filled with the polymeric foam so that the workpieces are totally immersed in the foam coating as the workpieces pass through the chamber. Openings for introducing the workpieces into and discharging the workpieces from the chamber have a configuration complementary to the transverse configuration of the workpieces. The foam coating is introduced into the chamber both above and below the path of the workpieces through the coating chamber to assure that the coating chamber remains fully charged with the foam coating. Brushes or wiper blades spread the foam coating over the exterior surfaces of the workpieces.

Abstract: Molded fibrous workpieces of various cross sectional configurations are coated with a polymeric latex foam coating material to encapsulate fibers and dust within the exterior surfaces of the workpieces. The foam coating is applied by passing the workpieces through a coating chamber filled with the polymeric foam so that the workpieces are totally immersed in the foam coating as the workpieces pass through the chamber. Openings for introducing the workpieces into and discharging the workpieces from the chamber have a configuration complementary to the transverse configuration of the workpieces. The foam coating is introduced into the chamber both above and below the path of the workpieces through the coating chamber to assure that the coating chamber remains fully charged with the foam coating. Brushes or wiper blades spread the foam coating over the exterior surfaces of the workpieces.

Abstract: A rigid, glass fiber airduct for conveying an airstream has an interior surface, adapted to be in contact with the airstream, which is coated with a polymeric coating comprising an organic or inorganic biocide. The polymeric coating has a dry solids content between 10 and 20 grams per square foot of duct board surface and retains its abrasion strength and puncture resistance whereby the interior surface of the airduct can be cleaned by conventional industrial or commercial cleaning procedures while in service without exposing glass fibers to the airstream.

Abstract: A rigid fiber glass air duct for conveying an airstream has an interior surface, adapted to be in contact with the airstream, which is coated with a polymeric coating with an organic biocide. The polymeric coating has a dry solids content of between 10 and 20 grams per square foot of duct board surface and retains its abrasion strength and puncture resistance whereby the interior surface of the duct can be cleaned by conventional industrial or commercial cleaning methods while in service without exposing glass fibers to the airstream.