Packaged electrical heating element

Claim 1

An elongate flexible heating package having sufficient flexibility to conform to an item to be heated to which the package is secured and adapted to improve the heating efficiency of an elongate, electrically insulated, electrical heating element contained within the package, said package comprising; a first layer comprising a wall made from a flexible heat conductive material that extends longitudinally along the length of the package and is adapted to establish a heat contacting relationship to the item to be heated to which the package is secured, a second layer secured along the length of the package to the side of said first layer that faces away from the item to be heated to which the package is secured, said second layer comprising a wall made from a flexible heat insulative material, a third layer secured along the length of the package to the side of said second layer that faces away from said first layer, said third layer comprising a wall made from a flexible heat resistant material that is adapted to protect said second layer, said third layer comprising a metal foil having a mylar film disposed along the length of the package on the side of said third layer that faces away from said second layer, said first, second and third layers being of substantially the same width, and an elongated cavity extending along the length of the package between a portion of said first layer wall and the composite wall comprising a portion of said second and said third layer walls, said cavity containing said electrical heating element and having an open-ended cross-sectional configuration that permits the heating element to be axially inserted into and removed from the cavity for replacement and repair without having to remove the package from the item to be heated to which the package is secured.