Apparatus and methods of ceramic pre-cursor batch rheology control

Patent metadata

Field	Value
Publication number	US-11220021-B2
Application number	US-201716321882-A
Country	US
Kind code	B2
Filing date	Aug 3, 2017
Priority date	Aug 3, 2016
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

A system (100) and method to control rheology of ceramic pre-cursor batch during extrusion is described herein. An extrusion system (100) comprises an extruder (122) with an input port (144) configured to feed ceramic pre-cursor batch into a first section (120) of an extruder barrel and a discharge port configured to extrude a ceramic pre-cursor extrudate (172) out of the extruder barrel downstream of the input port (144). A liquid injector (210) is configured to inject liquid into the ceramic pre-cursor batch. A sensor (106) is configured to detect a rheology characteristic of the ceramic pre-cursor batch. A controller (108) is configured (i) to receive the rheology characteristic from the sensor (106), (ii) compare the rheology characteristic to a predetermined rheology value of the ceramic pre-cursor batch, and (iii) generate a command based on the comparison. A liquid regulator (110) is configured to receive the command and adjust liquid flow to the liquid injector (210) based on the command.

First claim

The invention claimed is:

1. An extrusion system, comprising:
an extruder, comprising:
an input port configured to feed ceramic pre-cursor batch into a first section of an extruder barrel, and
a discharge port configured to extrude a ceramic pre-cursor extrudate out of the extruder barrel downstream of the input port;

a first liquid injector configured to inject liquid into the ceramic pre-cursor batch upstream of the extruder;
a second liquid injector configured to inject liquid into the ceramic pre-cursor batch within the extruder;
a sensor configured to detect a rheology characteristic of the ceramic pre-cursor batch;
a controller configured (i) to receive the rheology characteristic from the sensor, (ii) compare the rheology characteristic to a predetermined rheology value of the ceramic pre-cursor batch, and (iii) generate a command based on the comparison; and
a liquid regulator configured to receive the command and adjust liquid flow to the first liquid injector and the second liquid injector based on the command.

2. The system of claim 1 , wherein the rheology characteristic comprises at least one of (i) a liquid content of the ceramic pre-cursor batch, (ii) a stiffness of the ceramic pre-cursor batch, (iii) a wall drag of the ceramic pre-cursor batch, (iv) a die pressure, (v) a barrel pressure, (vi) a pressure change at a mixing plate, (vii) an extrusion torque, (viii) a ceramic pre-cursor batch temperature, and (ix) a screen pressure.

3. The system claim 1 , wherein the predetermined rheology value comprises (i) a first liquid value for extruder die start-up conditions and (ii) a second liquid value less than the first value for steady-state extruder conditions.

4. The system of claim 1 , wherein the first liquid injector is configured to inject liquid into the ceramic pre-cursor batch upstream of the first section of the extruder barrel.

5. The system of claim 1 , wherein the second liquid injector is configured to inject liquid into the ceramic pre-cursor batch in a second section of the extruder barrel downstream of the first section of the extruder barrel and upstream of the discharge port of the extruder barrel.

6. The system of claim 1 , wherein the first liquid injector and/or the second liquid injector are configured to inject liquid into the extruder barrel at a pressure of 0.5 psi to 10 psi.

7. The system of claim 1 , wherein the sensor is configured to detect the liquid content in the ceramic pre-cursor batch upstream of the input port.

8. The system of claim 1 , wherein the sensor is configured to detect the liquid content in the ceramic pre-cursor batch downstream of the discharge port.

9. The system of claim 1 , wherein the sensor is configured to detect at least one of oil-based fluid content and water-based fluid content as the liquid content in the ceramic pre-cursor batch.

10. The system of claim 1 , further comprising a die coupled to the discharge port, the die comprising:
a die body;
feed holes configured to accept the ceramic pre-cursor batch at the upstream surface, wherein the feedholes are disposed in an upstream surface of the die body and extend downstream into the die body; and
exit slots configured to shape the ceramic pre-cursor batch into a honeycomb extrudate, wherein the exits slots are arranged in a matrix pattern intersecting the feedholes in the die body and extend to a discharge surface of the die.

11. The system of claim 1 , wherein the controller is configured to (i) generate the command with an increase liquid flow value, when the rheology characteristic is less than the predetermined rheology value, and (ii) generate the command with a decrease liquid flow value when the rheology characteristic is more than the predetermined rheology value, and
wherein the liquid regulator is configured to adjust more liquid flow to the first liquid injector or the second liquid injector in response to receipt of the command with the increase liquid flow value, and
wherein the liquid regulator is configured to adjust less liquid flow to the first liquid injector or the second liquid injector in response to receipt of the command with the decrease liquid flow value.

12. The system of claim 1 , further comprising a vacuum device configured to evacuate gas from the ceramic pre-cursor batch in a third section of the extruder barrel downstream of the input port, downstream of the second liquid injector, and upstream of the discharge port.

13. A method of manufacturing a ceramic pre-cursor extrudate, the method comprising:
disposing a ceramic pre-cursor batch into a first section of an extruder barrel;
injecting liquid into the ceramic pre-cursor batch via a first liquid injector and a second liquid injector;
extruding a ceramic pre-cursor extrudate out of the extruder barrel downstream of the disposing and the injecting;
detecting a rheology characteristic of the ceramic pre-cursor batch;
comparing the rheology characteristic to a predetermined rheology value of the ceramic pre-cursor batch; and
adjusting an amount of liquid injected into the ceramic pre-cursor batch based on the comparing.

14. The method of claim 13 , wherein the predetermined rheology value comprises (i) a first liquid value for extruder die start-up conditions and (ii) a second liquid value less than the first value for steady-state extruder conditions.

15. The method of claim 13 , wherein the predetermined rheology value is at least one of (i) a die pressure, (ii) a barrel pressure, (iii) a pressure change at the mixing plate, (iv) a screen pressure, and (v) a ceramic pre-cursor batch temperature.

16. The method of claim 13 , wherein the injecting is upstream of the first section.

17. The method of claim 13 , wherein the injecting is in a second section of the extruder barrel downstream of the first section.

18. The method of claim 13 , wherein the detecting comprises detecting the rheology characteristic in the ceramic pre-cursor batch upstream of the injecting.

19. The method of claim 13 , wherein the detecting comprises detecting the rheology characteristic in the ceramic pre-cursor batch downstream of the extruding.

20. The method of claim 13 , wherein the extruding comprises forming a honeycomb extrudate.

Assignees

• Corning Inc

Inventors

• Malarkey Christopher John
• Walsh Conor James

Classifications

• B28B3/224

  Twin screw extruders, e.g. double shaft extruders · CPC title

• B28B17/0081

  Process control · CPC title

• B29C48/11

  comprising two or more partially or fully enclosed cavities, e.g. honeycomb-shaped · CPC title

• B30B11/24

  using screws or worms · CPC title

• B29C2948/922

  Viscosity; Melt flow index [MFI]; Molecular weight · CPC title