Extrusion dies for honeycomb body
An extrusion die ( 100 ) for a honeycomb body, the die ( 100 ) including: an input surface ( 102 ); an opposing output surface ( 104 ); feed holes ( 108 ) extending from the input surface ( 102 ) toward the output surface ( 104 ); discharge slots ( 106 ) having a slot width (SW) and a slot length (SL), and extending from the output surface ( 104 ) toward the input surface ( 102 ); and a plenum ( 130 ) fluidly connecting the feed holes ( 108 ) and the discharge slots ( 106 ). The plenum ( 130 ) may include chambers ( 132 ) connected to the feed holes ( 108 ) and including tapered outlets ( 134 ) connected to the discharge slots ( 106 ). The plenum ( 133 ) may include first chambers ( 132 A) connected to the feed holes ( 108 ) and including first tapered outlets ( 134 A), and second chambers ( 132 B) connected to the first outlets and including second tapered outlets ( 134 B) connected to the discharge slots ( 106 ).
1. An extrusion die having an input surface and an opposing output surface, the extrusion die comprising:
a feed hole plate forming the input surface and comprising feed holes extending from the input surface toward the output surface;
an array of substantially parallel pins extending from the feed hole plate and forming at least a portion of the output surface;
discharge slots at least partially defined by opposing first surfaces of adjacent pins, the discharge slots having a slot width (SW) and a slot length (SL), and arranged in an intersecting honeycomb pattern extending from the output surface toward the input surface; and
a plenum fluidly connecting the feed holes and the discharge slots, the plenum arranged in the intersecting honeycomb pattern and comprising:
first chambers at least partially defined by opposing second surfaces of adjacent pins, the first chambers extending from the feed holes, the first chambers having a first chamber width (CW 1 ) and a first chamber length (CL 1 ); and
second chambers at least partially defined by opposing third surfaces of adjacent pins, the second chambers extending from the first chambers to the discharge slots, the second chambers having a second chamber width (CW 2 ) and a second chamber length (CL 2 ),
wherein the first chamber width CW 1 is greater than the second chamber width CW 2 .
2. The extrusion die of claim 1 , wherein a SL/SW ratio ranges from about 15 to about 30.
3. The extrusion die of claim 1 , wherein a CL 1 /CW 1 ratio ranges from about 6 to about 10.
4. The extrusion die of claim 1 , wherein a CW 2 /SW ratio ranges from about 3 to about 5.
5. The extrusion die of claim 1 , wherein a CW 1 /CW 2 ratio ranges from about 1.2 to about 1.5.
6. The extrusion die of claim 1 , wherein a CL 2 /CW 2 ratio ranges from about 2 to about 6.
7. The extrusion die of claim 1 , wherein the slot width SW ranges from about 0.025 mm to about 0.056 mm.
8. The extrusion die of claim 1 , wherein:
the first chambers comprise tapered outlets respectively disposed in fluid communication with the second chambers;
the second chambers comprise second tapered outlets respectively disposed in fluid communication with the discharge slots; and
the first outlets and the second outlets form an exit angle ranging from about 20° to about 45°, with respect to a lengthwise axis of the corresponding first and second chambers.
9. The extrusion die of claim 8 , wherein the exit angle ranges from about 25° to about 35°.
10. The extrusion die of claim 1 , wherein the first chamber length CL 1 is greater than or equal to the second chamber length CL 2 .