Extrusion die for forming thin-walled honeycomb structures

摘要

An extrusion die is disclosed for extruding a honeycomb-shaped structure having rectangular channels. The die is formed of a hard, rigid material, preferably metal, and includes a body plate (10) and an abutting face plate (20). The outlet face of the body plate (10) is brazed to the inlet face of the face plate (20). The body plate (10) has a plurality of slightly staggered primary feed holes (12), the outlet ends of each communicating with an associated feed reservoir (26), the latter each defined by a recess or depression in the inlet surface of the face plate (20). Each feed reservoir (26) communicates with the inlet ends of three associated secondary feed holes (30). The outlet surface of the face plate integrally carries a plurality of intersecting slot segments (22) defining rectangular pins (24). The outlet end of each secondary feed hole communicates with and feeds an associated intersection of groove segments (22). The arrangement is such that the number of slot intersections is greater than the number of secondary feed holes, with two diagonally opposite corners of any pin communicating with a secondary feed hole. The combination of rectangular pins (discharge slots) and staggering of the main feed holes maximizes the die interface brazing area to thereby realize honeycomb cell densities of 900 - 1400 cells per square inch.