Patent ID: 6148867
Filing Date: 2000-11-21
Classification: B32B,E04C,F16L,F24F,Y10T

Abstract:
A kerfed insulation board for forming a duct of a preselected transverse dimensions and cross section comprising:an insulation board having a first major surface adapted to be an interior surface of a duct formed from said insulation board and a second major surface adapted to be an outer surface of a duct formed from said insulation board; said insulation board having a length adapted to extend parallel to a longitudinal centerline of a duct formed from said insulation board, a width and a thickness;kerfs in said first major surface of said insulation board for making said insulation board flexible in a direction of said width of said insulation board and foldable into a tubular configuration of preselected transverse dimensions and cross section; each of said kerfs having a depth; each of said kerfs extending parallel with respect to and being spaced from other of said kerfs; each of said kerfs extending said length of said insulation board; each of said kerfs having sidewalls which extend from a kerf base portion adjacent but spaced inwardly from said second major surface of said insulation board to said first major surface of said insulation board; each of said kerfs having shoulder portions adjoining said first major surface of said insulation board; and each of said kerfs having a width at said first major surface of said insulation board; said width of said kerfs at said first major surface of said insulation board pressing said shoulder portions of said kerfs into abutment with said insulation in said shoulder portions being in compression, when said insulation board is formed into a duct of said preselected transverse dimensions and cross section, to retain said insulation board in said preselected transverse cross section with no exposure of the kerf sidewalls at the interior surface of the duct and with any loose fibers or dust from said kerf sidewalls being confined within said kerfs.