Patent ID: 6964282

Claim:
A fibrous pipe insulation system, comprising: a tubular core of fibrous insulation having a length and a longitudinal axis; the tubular core having a substantially cylindrical outer surface; the tubular core having a substantially cylindrical inner surface; the tubular core having a wall extending between the cylindrical outer surface and the cylindrical inner surface; the wall of the tubular core having a radially extending thickness; the wall of the tubular core having a first slit extending completely there through; the first slit extending parallel to the longitudinal axis of the tubular core for the length of the tubular core; the tubular core having a second slit in the inner surface of the tubular core; the second slit being substantially opposite the first slit; the second slit extending parallel to the longitudinal axis of the tubular core for the length of the tubular core; and the second slit extending only partially through the wall of the tubular core to form a longitudinally extending hinge in the tubular core that permits the tubular core to be opened and closed to place the tubular core about a pipe; and a closed cell foam layer coextensive with and bonded to the substantially cylindrical outer surface of the tubular core; the closed cell foam layer being flexible so that the tubular core with the closed cell foam layer can be opened, placed about a pipe, and closed without cracking the closed cell foam layer; and the substantially cylindrical outer surface of the core has a first radius; the substantially cylindrical inner surface of the core has a second radius; and for a temperature at the substantially cylindrical inner surface of the core between 35° F. and 65° F. and a temperature of 90° F. and a relative humidity of 90% at the substantially cylindrical outer surface of the core, a dew point temperature is attained within the wall of the core at a radial distance less than the first radius and spaced inwardly from the substantially cylindrical outer wall of the core and greater than the second radius and spaced outwardly from the substantially cylindrical inner wall of the core.