Extrusion systems and methods with temperature control

An extrusion system for controlling the extrusion of a ceramic batch material to form an extrudate having an outer surface and a desired extrudate shape, comprising:

• an extruder having a long axis and a cavity configured to contain the ceramic batch material and that contains at least one extrusion screw operable to cause a flow of the ceramic batch material;
• an extrusion die operably arranged at an output end of the extruder;
• a front section of the extruder that resides immediately adjacent the extrusion die;
• a plurality of heating elements azimuthally arranged about at least a portion of the cavity periphery at the front section and configured to provide, in response to power signals, localized heating of the ceramic batch material as it flows through the front section;
• a plurality of first temperature sensors azimuthally arranged relative to the long axis at the extruder front end and configured to make non-contact measurements of surface temperatures of the extrudate outer surface and generate first temperature signals representative of the measured surface temperatures;
• and
• a temperature controller operably connected to the plurality of heating elements and the plurality of first temperature sensors and configured to receive the first temperature signals and control, via the power signals, amounts of heat generated by the heating elements in response to the measured surface temperatures.

An extruder system for controlling the extrusion of a ceramic batch material to form an extrudate having an outer surface and a desired extrudate shape, comprising:

• an extrusion die having a first cavity and an output aperture;
• a first extruder section arranged immediately adjacent the extrusion die and having a second cavity that is open to the first cavity;
• a second extruder section arranged immediately adjacent the first extruder section configured to cause the flow of the ceramic batch material through the second cavity to the first cavity and out of the extrusion die output end to form the extrudate;
• a plurality of first temperature sensors azimuthally disposed about the extrusion die output aperture and operable to measure temperatures of the extrudate outer surface and in response thereto generate first temperature signals;
• a plurality of first heating elements azimuthally disposed about the second cavity and operable to locally heat the ceramic batch material flowing through the second cavity in response to power signals;
• and
• a temperature control unit operably connected to the first temperature sensors and the heating elements and configured to receive the first temperature signals and control the power signals in a first control loop to control amounts of heat generated by the heating element in response to the measured surface temperatures.