Methods of manufacturing a die body

Abstract

A method of making a die body configured to extrude a honeycomb body, the method comprising the step (I) of manufacturing a die body and the step (II) of predetermining an upstream slot width W1 of the die body such that the upstream slot width W1 is optimized while a root of each die pin includes a section modulus within a predetermined section modulus range. The method still further comprises the step (III) of predetermining a slot length L such that a pin stress is within a predetermined pin stress range.

What is claimed is: 
     
         1 . A method of making a die body configured to extrude a honeycomb body, the method comprising the steps of:
 (I) manufacturing a die body including a plurality of feed holes and an array of pins that are spaced apart to define a honeycomb network of discharge slots in fluid communication with the feed holes, wherein each discharge slot is manufactured with a slot length L, each discharge slot is further manufactured with an upstream portion with an upstream slot width W1 in fluid communication with at least one feed hole and a downstream portion with a downstream slot width W2 in fluid communication with an extrusion face of the die body, and the upstream portion and the downstream portion of each discharge slot are manufactured such that W1>W2;   (II) predetermining the upstream slot width W1 such that the upstream slot width W1 is optimized while a root of each die pin includes a section modulus within a predetermined optimized section modulus range; and   (III) predetermining the slot length L such that a pin stress is within a predetermined pin stress range.   
     
     
         2 . The method of  claim 1 , wherein step (II) predetermines the upstream slot width W1 such that the upstream slot width W1 is maximized while the root of each die pin includes a section modulus within a predetermined maximized section modulus range. 
     
     
         3 . The method of  claim 1 , wherein the predetermined optimized section modulus range of step (II) includes a range of from about 9.3×10 −6  cm 3  to about 2.8×10 −5  cm 3 . 
     
     
         4 . The method of  claim 1 , wherein the predetermined pin stress range of step (III) includes a range of from about 240 MPa to about 750 MPa. 
     
     
         5 . The method of  claim 1 , wherein the predetermined pin stress range of step (III) is based on a calculated pin stress of a reference die body including a reference slot having a substantially constant reference slot width substantially equal to W2 along an overall length of the reference slot. 
     
     
         6 . The method of  claim 1 , wherein the predetermined stress range of step (III) is determined based by a calculated pin stress of the die body undergoing a cleaning procedure. 
     
     
         7 . The method of  claim 1 , wherein step (I) includes manufacturing the die body as a monolithic single piece die body. 
     
     
         8 . The method of  claim 1 , wherein step (I) includes manufacturing the die body with L≦about 2.5 mm. 
     
     
         9 . The method of  claim 1 , wherein step (I) includes manufacturing the die body with W2≦about 255 μm. 
     
     
         10 . The method of  claim 1 , wherein step (I) manufactures the upstream portion of the slot with a length L1 and the downstream portion of the slot with a length L2, wherein L≧about L1+L2. 
     
     
         11 . The method of  claim 1 , wherein step (I) manufactures each discharge slot with a transition region between the upstream portion and the downstream portion of the discharge slot, the transition region including a transition surface extending at an angle α from a surface of the upstream portion to a surface of the downstream portion of the discharge slot, wherein 45°≦α≦60°. 
     
     
         12 . The method of  claim 1 , wherein step (I) manufactures at least one pin of the array of pins with a divot located within the downstream portion of the discharge slot. 
     
     
         13 . A method of making a die body configured to extrude a honeycomb body, the method comprising the steps of:
 (I) manufacturing a die body including a plurality of feed holes and an array of pins that are spaced apart to define a honeycomb network of discharge slots in fluid communication with the feed holes, wherein each discharge slot is manufactured with a slot length L, each discharge slot is further manufactured with an upstream portion with an upstream slot width W1 in fluid communication with at least one feed hole and a downstream portion with a downstream slot width W2 in fluid communication with an extrusion face of the die body, and the upstream portion and the downstream portion of each discharge slot are manufactured such that W1>W2;   (II) predetermining the upstream slot width W1 to provide a root of each die pin includes a section modulus within a predetermined section modulus range of from about 9.3×10 −6  cm 3  to about 2.8×10 −5  cm 3 ; and   (III) predetermining the slot length L such that a pin stress is within a predetermined pin stress range based on a calculated pin stress of a reference die body including a reference slot having a substantially constant reference slot width substantially equal to W2 along an overall length of the reference slot.   
     
     
         14 . The method of  claim 13 , wherein the predetermined pin stress range of step (III) includes a range of from about 240 MPa to about 750 MPa. 
     
     
         15 . The method of  claim 13 , wherein step (II) predetermines the upstream slot width W1 such that the upstream slot width W1 is maximized while the root of each die pin includes a section modulus within the predetermined section modulus range. 
     
     
         16 . The method of  claim 13 , wherein step (I) includes manufacturing the die body as a monolithic single piece die body. 
     
     
         17 . A method of making a die body configured to extrude a honeycomb body, the method comprising the steps of:
 (I) manufacturing a die body including a plurality of feed holes and an array of pins that are spaced apart to define a honeycomb network of discharge slots in fluid communication with the feed holes, wherein each discharge slot is manufactured with a slot length L, each discharge slot is further manufactured with an upstream portion with an upstream slot width W1 in fluid communication with at least one feed hole and a downstream portion with a downstream slot width W2 in fluid communication with an extrusion face of the die body, and the upstream portion and the downstream portion of each discharge slot are manufactured such that W1>W2;   (II) predetermining the upstream slot width W1 to provide a root of each die pin includes a section modulus within a predetermined section modulus range of from about 9.3×10 −6  cm 3  to about 2.8×10 −5  cm 3 ; and   (III) predetermining the slot length L such that a pin stress is within a predetermined pin stress range determined based by a calculated pin stress of the die body undergoing a cleaning procedure.   
     
     
         18 . The method of  claim 17 , wherein the predetermined pin stress range of step (III) includes a range of from about 240 MPa to about 750 MPa. 
     
     
         19 . The method of  claim 17 , wherein step (II) predetermines the upstream slot width W1 such that the upstream slot width W1 is maximized while the root of each die pin includes a section modulus within the predetermined section modulus range. 
     
     
         20 . The method of  claim 17 , wherein step (I) includes manufacturing the die body as a monolithic single piece die body.