PROCESS AND APPARATUS FOR MOLDING A FILTER

摘要

The invention provides a method for forming a fibrous layer within a tubular support, which comprises the steps of: (a) providing the tubular support; (b) providing forming mesh over me curved surface of the support and closing its ends against escape of fluid; and (c) introducing fibrous slurry (e.g. an aqueous slurry of borosilicate glass microfibers and water dispersible heat curable acrylic resin at a pH of about 3) from a pressurized source into an annular molding space between a rotary molding torpedo and an inner surface of the support, the torpedo having at least one channel for slurry opening along a curved surface thereof, fibers in the slurry collecting within the forming mesh to form the layer. The invention also provides apparatus for forming a fibrous layer within a tubular support, which comprises:(a) a mould having a molding space for the tubular support; (b) forming mesh in the molding space for covering an exterior curved surface of the support, the forming mesh being configured to collect fibers and permit liquid to pass through it; (c) headstock and tailstock end closures for closing headstock and tailstock ends of the support against escape of fluid; (d) a rotary molding torpedo extendible into and retractable from the molding space for defining with an internal curved surface of the support an annular space for formation of the fibrous layer, the torpedo having at least one channel for slurry opening along a curved surface thereof; (e) a drive coupled to the torpedo for rotation thereof during molding; and (f)a supply line for supplying fibrous slurry from a pressurized source to the torpedo for flow into and through the molding space; and (g) suction means for withdrawing fluid from the molding space.