Fire door
AssigneeGeorgia-Pacific Corporation
InventorsCharles W. Lehnert, James R. Van Dyke, Ray W. Hinkel
Life of this patent
Estimating the term…
Abstract
A fire door comprising a core and edge banding, the principal ingredients of the core being expanded perlite, gypsum and cement, the edge banding comprising a strip of natural wood, a strip of a cast mixture of which the principal ingredient is gypsum and an intervening strip of plastic laminate.
Claims11
Edge banding applied to a planar fire door core having a mean plane and planar edge surfaces perpendicular to said mean plane, the edge banding comprising a strip of natural wood, a strip of fiber reinforced thermoset plastic laminate and a strip of a cast gypsum mixture of the following composition:
- ______________________________________ Weight % of Set and Dried Composition ______________________________________ gypsum dihydrate 65-75 clay 4-5.5 raw vermiculite 4.5-5.5 glass fiber 0.7-1.5 wood chips 5-7 paper fiber 0.8-1.3 (kraft or sulfite) resin binder (solids) 9.5-11.5 dispersant 0.7-1.3 accelerator 0.7-1 defoamer 0.01-0.03 ______________________________________
- said cast mixture having a density of at least 60.0 lbs./cu. ft., each of said strips having a pair of oppositely facing surfaces lying in a plane transverse to the mean plane of the fire door core to which the banding is to be affixed, one of said pair of strip surfaces facing inwardly toward the fire foor core edge, the other of said pair of strip surfaces facing outwardly away from the fire door core edge, the inwardly-facing surface of the plastic laminate strip being adhesively fastened to the outwardly surface of the gypsum composition strip, and the outwardly-facing surface of the plastic laminate strip being adhesively fastened to the inwardly-facing surface of the wood strip, the inwardly-facing surface of the gypsum composition strip being presented for fastening along an edge surface of the fire door.
A fire door for use in a doorway having vertical and horizontal jamb surfaces with a door edge stop positioned inside at least one of the vertical jamb surfaces, the door comprising a planar door core having a mean plane and vertical and horizontal planar edge surfaces perpendicular to said mean plane, and edge banding on at least one of the veritcal edges of the core, the core comprising a slab molded from a fire resistant composition, and the edge banding comprising an assembly of at least three strips, the outermost strip being a strip of natural wood, an intermediate strip being formed of fiber reinforced plastic laminate, and an innermost strip being formed of a cast gypsum composition, said strips having a pair of oppositely presented surfaces transverse to the mean plane of the door core, said edge banding being mounted at an edge of the core with the wood strip positioned outward of the plastic laminate strip, said gypsum composition strip being positioned at the edge of the core, and the plastic laminate strip being positioned between the gypsum composition strip and the wood strip, said wood strip having a thickness in the direction of the mean plane of the core, which thickness is not greater than the depth of the door edge stop inside the jamb surface, so that thermal shielding of at least the wood strip is provided by the door edge strip at the jamb surface of the door.
A method for making an edge-banded fire door comprising molding a door core from a mixture of particulate materials including at least 50 weight % of expanded perlite, at least 10 weight % of calcined gypsum, and an aqueous binder, compressing said mixture to form a molded door core having edges transverse to the mean plane of the core, pre-assembling edge-banding from a strip of natural wood, a strip of fiber reinforced thermoset plastic laminate, and a strip of cast gypsum composition, the gypsum composition strip being cast from particulate materials including at least 60 weight % of calcined alpha gypsum, fibers, an accelerator and an aqueous binder, and each of said strips having a pair of oppositely presented surfaces, one of said surfaces facing outwardly and the other of said surfaces facing inwardly, the inwardly-facing and outwardly-facing surfaces of the plastic laminate being adhesively fastened to the outwardly-facing surface of the gypsum composition strip and the inwardly-facing surface of the wood strip, respectively;
- and after the strips are adhesively fastened together, fastening the assembled edge banding along the edges of the core with the inwardly-facing surface of the cast gypsum composition strip against the edge of the core.
A fire door comprising a core and tripartite edge banding, the core having a mean plane and planar edge surface perpendicular to the mean plane of the core and comprising a molded fire-resistant composition having a density of not more than 35 lbs./cu. ft., and the tripartite edge banding comprising a composite of at least three strips comprising a first strip of natural wood, a second strip of fiber reinforced thermoset plastic laminate, and a third strip of a cast mixture of the following ingredients in the weight percentages indicated:
- ______________________________________ Weight % of Set and Dried Composition ______________________________________ gypsum dihydrate 65-75 clay 4-5.5 raw vermiculite 4.5-5.5 glass fiber 0.7-1.5 wood chips 5-7 paper fiber 0.8-1.3 (kraft or sulfite) resin binder (solids) 9.5-11.5 dispersant 0.7-1.3 accelerator 0.7-1 defoamer 0.01-0.03 ______________________________________
- said cast mixture having a density of from about 60 to about 75 lbs./cu. ft., each of said strips having a pair of oppositely presented surfaces transverse to the mean plane of said core, one of said strip surfaces facing inwardly toward the core edge, the other of said strip surfaces facing outwardly away from the core edge, the inwardly-facing surface of the plastic laminate strip being adhesively fastened to the outwardly-facing surface of the gypsum composition strip, the outwardly-facing surface of the plastic laminate strip being adhesively fastened to the inwardly facing surface of the wood strip, and the inwardly-facing surface of the gypsum composition strip being mounted against at least one core edge.
Dependencies are inferred from the claim text.