Diamond insert with heat transfer bore

Abstract

An improved diamond coated bit tip insert on a bit/holder, tool, and/or pick for road milling operations that includes a body including a tip and a base subjacent the tip, the tip including an overlay on an outer surface of the tip. The bit tip insert also includes at least one heat transfer bore extending from a distal end and/or bottom of the body to a bore termination adjacent the tip. The at least one bore of the bit tip insert is adapted to allow inward contraction when the overlay transfers heat into the base during operation.

1 . A bit tip insert comprising:
 a body comprising a tip and a base subjacent the tip, the tip including an overlay on an outer surface of the tip; and   a first bore axially extending from a distal end of the body to a first bore termination adjacent the tip, the first bore adapted to allow inward contraction when the overlay transfers heat into the base during operation.   
     
     
         2 . The bit tip insert of  claim 1 , wherein the overlay comprises at least one of a polycrystalline diamond, industrial diamond, natural diamond, polycrystalline diamond composite material, and polycrystalline diamond compact material. 
     
     
         3 . The bit tip insert of  claim 1 , wherein the overlay comprises at least one of:
 at least one coating on the outer surface of the tip; and   at least one layer on the outer surface of the tip.   
     
     
         4 . The bit tip insert of  claim 3 , wherein the at least one coating and at least one layer on the outer surface of the tip is formed by a high pressure high temperature (HPHT) process. 
     
     
         5 . The bit tip insert of  claim 1 , further comprising:
 a tapered portion adjacent a distal end of the base.   
     
     
         6 . The bit tip insert of  claim 5 , further comprising:
 at least one second bore extending from the tapered portion adjacent a distal end of the base, each second bore including a second bore termination adjacent the tip, and each second bore adapted to allow inward contraction when the overlay transfers heat into the base during operation.   
     
     
         7 . The bit tip insert of  claim 1 , wherein the base is made of at least one of steel and tungsten carbide. 
     
     
         8 . The bit tip insert of  claim 1 , wherein the tip comprises one of a frustoconical shape, a flat generally cylindrical puck shape, an arcuate shape, a parabolic shape, and a conical shape, at least one of the conical shape and the parabolic shape including a parabolic curved section below an apex thereof. 
     
     
         9 . The bit tip insert of  claim 1 , wherein a sidewall of the base is one of cylindrical and tapered inwardly toward a bottom of the base. 
     
     
         10 . The bit tip insert of  claim 1 , wherein a distance between the first bore termination and an apex of the tip is approximately a minimum one of 3/16 inch and ¼ inch. 
     
     
         11 . The bit tip insert of  claim 1 , further comprising:
 an insert disposed within the first bore of the bit tip insert, the insert adapted to transfer heat from the bit tip insert.   
     
     
         12 . The bit tip insert of  claim 11 , wherein the insert is made of a high heat transfer material. 
     
     
         13 . The bit tip insert of  claim 11 , wherein the insert is made of copper. 
     
     
         14 . The bit tip insert of  claim 1 , further comprising:
 a plurality of diamond particles disposed within the first bore of the bit tip insert, the diamond particles adapted to distribute heat generated at the tip.   
     
     
         15 . The bit tip insert of  claim 14 , wherein the plurality of diamond particles are at least one of brazed in the first bore, packed firmly within the first bore, and bonded with epoxy in the first bore. 
     
     
         16 . The bit tip insert of  claim 14 , further comprising:
 a metal plug disposed within the first bore between the plurality of diamond particles and the distal end of the body.   
     
     
         17 . A tool comprising:
 a body comprising a first bore extending inwardly from a forward end of the body;   a shank extending centrally axially from a bottom of the body; and   a bit tip insert disposed in the first bore, the bit tip insert comprising:
 a bit tip body comprising a tip and a base subjacent the tip, the tip including an overlay on an outer surface of the tip; and 
 a second bore axially extending from a distal end of the bit tip body to a second bore termination adjacent the tip, the second bore adapted to allow inward contraction when the overlay transfers heat into the base during operation. 
   
     
     
         18 . The bit holder of  claim 17 , wherein the first bore is one of cylindrical and tapered inwardly. 
     
     
         19 . The tool of  claim 17 , further comprising:
 a tapered portion adjacent the distal end of the bit tip body of the bit tip insert, the tapered portion adapted to contact a portion of the first bore of the body.   
     
     
         20 . The tool of  claim 19 , further comprising:
 at least one third bore extending from the tapered portion adjacent a distal end of the base, each third bore including a third bore termination adjacent the tip, and each third bore adapted to allow inward contraction when the overlay transfers heat into the base during operation.   
     
     
         21 . The tool of  claim 17 , wherein the first bore is disposed in a forward extension adjacent the forward end of the body. 
     
     
         22 . The tool of  claim 21 , wherein the forward extension is tapered. 
     
     
         23 . The tool of  claim 21 , further comprising:
 an annular trough laterally extending from a distal end of the forward extension; and   an annular ring disposed around the forward extension and seated in the annular trough of the body.   
     
     
         24 . The tool of  claim 23 , wherein the annular ring is made of tungsten carbide. 
     
     
         25 . The tool of  claim 17 , wherein the overlay comprises at least one of a polycrystalline diamond, industrial diamond, natural diamond, polycrystalline diamond composite material, and polycrystalline diamond compact material. 
     
     
         26 . The tool of  claim 17 , wherein a sidewall of the base is one of cylindrical and tapered inwardly toward a bottom of the base. 
     
     
         27 . The tool of  claim 17 , wherein a distance between the second bore termination and an apex of the tip is approximately a minimum of one of 3/16 inch and ¼ inch. 
     
     
         28 . The tool of  claim 17 , further comprising:
 an insert having a first end and a second end, the first end of the insert disposed within the second bore of the bit tip insert, the insert adapted to transfer heat from the bit tip insert.   
     
     
         29 . The tool of  claim 28 , wherein the insert is made of a high heat transfer material. 
     
     
         30 . The tool of  claim 28 , wherein the insert is made of copper. 
     
     
         31 . The tool of  claim 17 , further comprising:
 a plurality of diamond particles disposed within the second bore of the bit tip insert, the diamond particles adapted to distribute heat generated at the tip.   
     
     
         32 . The tool of  claim 31 , wherein the plurality of diamond particles are at least one of brazed in the second bore, packed firmly within the second bore, and bonded with epoxy in the second bore. 
     
     
         33 . The tool of  claim 31 , further comprising:
 a metal plug disposed within the second bore between the plurality of diamond particles and the distal end of the bit tip body.   
     
     
         34 . The tool of  claim 28 , further comprising:
 a third bore axially extending from a bottom of the first bore of the body to a location adjacent the bottom of the first bore; and   the second end of the insert disposed within the third bore, the insert extending to the location adapted to provide a depth that sufficiently transfers high heat from the tip of the bit tip insert.   
     
     
         35 . The bit tip insert of  claim 11 , wherein the insert varies in diameter depending on the size of the bit tip insert. 
     
     
         36 . The tool of  claim 28 , wherein the insert varies in diameter depending on the size of the bit tip insert. 
     
     
         37 . The bit tip insert of  claim 11 , wherein the insert is one of solid and hollow. 
     
     
         38 . The tool of  claim 28 , wherein the insert is one of solid and hollow. 
     
     
         39 . The bit tip insert of  claim 1 , wherein the body has a diameter between at least ⅝ inch and up to and including 1¼ inch. 
     
     
         40 . The tool of  claim 17 , wherein the bit tip body has a diameter between at least ⅝ inch and up to and including 1¼ inch.