Threaded nozzle for a cutter bit

Abstract

A threaded nozzle for use in a cutter bit is disclosed. Threads are either machined into or pressed into a pressed powder nozzle then the nozzle is sintered. Threads of the nozzles of the present invention exhibit improved hardness and have a rougher surface finish than threads machined post-sintering. Shaping of the threads into the nozzle before sintering is also more economical and efficient than post-sintering machining.

1 . An unsintered, pressed powder nozzle for use in a cutter bit comprising:
 a body having an exterior face, an inlet end and a discharge end;   a bore extending through the body from the inlet end to the discharge end; and   external threads extending at least partially along the exterior face of the body of the unsintered nozzle.   
     
     
         2 . The unsintered, pressed powder nozzle for use in a cutter bit of  claim 1 , wherein the nozzle is made from cobalt tungsten carbide. 
     
     
         3 . The unsintered, pressed powder nozzle for use in a cutter bit of  claim 1 , wherein the external thread is separated by an undercut portion. 
     
     
         4 . The unsintered, pressed powder nozzle for use in a cutter bit of  claim 1 , wherein the external threads have a surface roughness of at least 40 microinches. 
     
     
         5 . The unsintered, pressed powder nozzle for use in a cutter bit of  claim 1 , wherein the external threads have a surface roughness greater than 50 microinches. 
     
     
         6 . The unsintered, pressed powder nozzle for use in a cutter bit of  claim 1 , wherein the external threads have a surface roughness of about 55 microinches to about 65 microinches. 
     
     
         7 . A threaded nozzle for use in a cutter bit comprising:
 a body comprising an exterior face, an inlet end and a discharge end;   a bore extending through the body from the inlet end to the discharge end; and   external threads extending at least partially along the exterior face of the body of the threaded nozzle;   wherein the external threads have a surface roughness of at least 40 microinches.   
     
     
         8 . The threaded nozzle for use in a cutter bit of  claim 7 , wherein the external threads have a surface roughness greater than 50 microinches. 
     
     
         9 . The threaded nozzle for use in a cutter bit of  claim 7 , wherein the external threads have a surface roughness of about 55 microinches to about 65 microinches. 
     
     
         10 . A method of producing a threaded nozzle for use in a cutter bit comprising the steps of:
 first providing a pressed powder nozzle blank;   second machining threads into the pressed powder nozzle blank; and   third sintering the pressed powder nozzle blank.   
     
     
         11 . The method of producing a threaded nozzle for use in a cutter bit of  claim 10 , wherein the threads are machined into the pressed powder blank using a turning operation. 
     
     
         12 . The method of producing a threaded nozzle for use in a cutter bit of  claim 10 , wherein the turning operation utilizes a CNC machine or a lathe. 
     
     
         13 . The method of producing a threaded nozzle for use in a cutter bit of  claim 11 , wherein the turning operation utilizes a thread cutting tool comprising a shank and a cutting tip having projection for forming an undercut portion between each thread. 
     
     
         14 . The method of producing a threaded nozzle for use in a cutter bit of  claim 10 , wherein the external threads of the threaded nozzle after sintering have a surface roughness of at least 40 microinches. 
     
     
         15 . The method of producing a threaded nozzle for use in a cutter bit of  claim 10 , wherein the external threads of the threaded nozzle have a surface roughness greater than 50 microinches after sintering. 
     
     
         16 . The method of producing a threaded nozzle for use in a cutter bit of  claim 10 , wherein the external threads of the threaded nozzle have a surface roughness of about 55 microinches to about 65 microinches after sintering. 
     
     
         17 . A method of producing a threaded nozzle for use in a cutter bit comprising the steps of:
 providing a die comprising a first end, a second end, a sleeve and a split insert having a thread forming section inserted into the sleeve;   inserting a first punch into a first end of the die;   filling the die with a metal powder or ceramic powder;   inserting a second punch into the second end of the die;   applying pressure to the powder within the die to create a pressed powder blank;   removing the pressed powder blank from the die; and   sintering the pressed powder blank.   
     
     
         18 . The method of producing a threaded nozzle for use in a cutter bit of  claim 17 , wherein the external threads of the threaded nozzle after sintering have a surface roughness of at least 40 microinches. 
     
     
         19 . The method of producing a threaded nozzle for use in a cutter bit of  claim 17 , wherein the external threads of the threaded nozzle after sintering have a surface roughness greater than 50 microinches. 
     
     
         20 . The method of producing a threaded nozzle for use in a cutter bit of  claim 17 , wherein the external threads of the threaded nozzle after sintering have a surface roughness of about 55 microinches to about 65 microinches.