Abstract: Disclosed are an improved apparatus for collecting fine fibers, such as glass fibers, having a mean diameter of less than two microns from a gaseous stream, a method of collecting fine fibers using the apparatus and the novel new product produced by this method. The improvement lies mainly in the way in which the collection drum is supported and sealed which allows the collection to take place at relatively high partial vacuums. The fiber is also consolidated in the gaseous stream by passing it through a duct having at least one approximately ninety degree turn therein.

Abstract: A method and apparatus for accumulating and densifying microfibers such as glass fibers having mean fiber diameters below 1-2 microns is disclosed. A fine fiber blanket having been collected on a collection surface is removed and wound up on a mandrel having a permeable surface while a partial vacuum, preferably exceeding one hundred inches of water column, is maintained in the interior of the mandrel.