Patent ID: 8343400

Claim:
A method of making a gravity-laid inorganic fiber web comprising melt-formed inorganic fibers, comprising: extruding inorganic material as a melt and solidifying the molten extrudate as fibers and collecting the solidified inorganic fibers; introducing the collected solidified inorganic fibers into a forming chamber that comprises a plurality of fiber-separating rollers provided in at least one row within the forming chamber and that comprises a moving endless belt screen; mechanically separating at least some of the inorganic fibers with the fiber-separating rollers; capturing any remaining agglomerates of the inorganic fibers by the moving endless belt screen and returning the captured agglomerates to the fiber-separating rollers to be mechanically separated by the fiber-separating rollers; collecting the mechanically separated inorganic fibers as a gravity-laid inorganic fiber mat; removing the gravity-laid inorganic fiber mat from the forming chamber; and, consolidating the gravity-laid inorganic fiber mat to form a gravity-laid inorganic fiber web.