Abstract: A honeycomb extrusion apparatus comprises a die body and a flow control device. The die body comprises an inlet end, an outlet end, a central axis, a first set of feedholes, a second set of feedholes, a set of central slots, and a set of outermost peripheral slots. The first set of feedholes extends from the inlet end to an interior interface portion of the die body. The second set of feedholes extends through the die body from the inlet end to the outlet end. The set of central slots extends from the outlet end to the interior interface portion of the die body. The set of outermost peripheral slots is disposed radially outwardly of the central slots. The interior interface portion of the die body is configured to allow flow of the batch material from the first set of feedholes to the central slots and to the outermost peripheral slots.

Abstract: Systems and methods for real-time, closed-loop shape control of extruded ceramic honeycomb structures are disclosed. Methods include extruding batch material through an extruder barrel and through an extruder die using at least one extrusion screw to form the extrudate, and measuring a shape of the extrudate immediately adjacent the die. The batch material water content is determined or measured, at least one of the extruder barrel and screw temperature are measured, and the extrusion screw rotation rate are measured. At least one of the batch material water content, barrel temperature, screw temperature and rotation rate is adjusted to maintain the extrudate shape to within a select tolerance.

Abstract: A honeycomb extrusion apparatus comprises a die body and a flow control device. The die body comprises an inlet end, an outlet end, a central axis, a first set of feedholes, a second set of feedholes, a set of central slots, and a set of outermost peripheral slots. The first set of feedholes extends from the inlet end to an interior interface portion of the die body. The second set of feedholes extends through the die body from the inlet end to the outlet end. The set of central slots extends from the outlet end to the interior interface portion of the die body. The set of outermost peripheral slots is disposed radially outwardly of the central slots. The interior interface portion of the die body is configured to allow flow of the batch material from the first set of feedholes to the central slots and to the outermost peripheral slots.

Abstract: Disclosed is a method and apparatus for forming a circumferential skin surrounding a central cellular structure of an extruded honeycomb article. The method and apparatus may be used to produce defect-free skins and/or skins having large thickness and a high degree of particle alignment thereby preferably exhibiting CTE comparable to the extruded webs. These benefits are achieved by providing a die and method wherein a flow, Q, exiting any two active ones of a plurality of peripheral slots forming the skin is substantially equal. Also disclosed is a thick-skinned ceramic article having a thick extruded skin (ts?>5 tw?) with an I-value comparable to the webs.