Cutting bit useful for impingement of earth strata

Abstract

A cutting bit for impinging earth strata wherein the cutting bit includes a highly wear-resistant elongate cutting bit body, which has an axial forward end and an axial rearward end, an enlarged dimension head portion at the axial forward end and a reduced dimension shank portion at the axial rearward end. The highly wear-resistant elongate cutting bit body has a maximum transverse dimension and a longitudinal axial length. The cutting bit includes a superhard insert, which is affixed to the head portion at the axial forward end of the cutting bit body. The cutting bit has a slimness ratio, which comprises the ratio of the maximum transverse dimension to the longitudinal axial length wherein the cutting bit exhibits a slimness ratio ranging between about 0.15 and about 0.60.

1 . A cutting bit for impinging earth strata, the cutting bit comprising:
 a highly wear-resistant elongate cutting bit body having an axial forward end and an axial rearward end, an enlarged dimension head portion at the axial forward end and a reduced dimension shank portion at the axial rearward end, and the highly wear-resistant elongate cutting bit body having a maximum transverse dimension and a longitudinal axial length;   a superhard insert affixed to the head portion at the axial forward end of the cutting bit body; and   a slimness ratio comprising the ratio of the maximum transverse dimension to the longitudinal axial length, and the slimness ratio ranging between about 0.15 and about 0.60.   
     
     
         2 . The cutting bit according to  claim 1  wherein at least a part of the highly wear-resistant cutting bit body comprising a hard component-matrix composite material to provide wear resistance, and the hard component matrix composite material consisting of a plurality of discrete hard constituents and matrix powder of hard particles and an infiltrant alloy bonded together to form the hard component-matrix composite; and
 the infiltrant alloy having a melting point between about 500 degrees Centigrade and about 1400 degrees Centigrade;   the matrix powder comprises one or more of the following: cast carbides, spherical sintered carbides, crushed cemented carbide particles, crushed cast carbide particles, crushed carbide particles, and cemented carbide powder, steel particles, carbonyl iron particles, and coated carbide particles;   the discrete hard constituents comprise one or more of cemented carbides and ceramics; sintered cemented tungsten carbide wherein a binder includes one or more of cobalt, nickel, iron and molybdenum; coated sintered cemented tungsten carbide wherein a binder includes one or more of cobalt, nickel, iron and molybdenum, and the coating comprises one or more of nickel, cobalt, iron and molybdenum; one or more of the carbides, nitrides, and borides of one or more of titanium, niobium, tantalum, hafnium, and zirconium; tungsten carbide; one or more of the coated carbides, coated nitrides, and coated borides of one or more of titanium, niobium, tantalum, hafnium, and zirconium wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; coated tungsten carbide wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; coated silicon carbide wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; coated silicon nitride wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; and coated boron carbide.   
     
     
         3 . The cutting bit according to  claim 1  wherein at least a part of the highly wear-resistant cutting bit body comprising a wear rotator to provide wear resistance and enhance rotation, and wherein the wear rotator being carried by the highly wear-resistance cutting bit body. 
     
     
         4 . The cutting bit according to  claim 3  wherein the wear rotator being attached to the cutting bit body using an attachment material. 
     
     
         5 . The cutting bit according to  claim 3  wherein the wear rotator being attached to the cutting bit body without an attachment material. 
     
     
         6 . The cutting bit according to  claim 1  wherein the highly wear-resistance cutting bit body comprising a substrate, and at least a part of the substrate having a coating layer thereon, and wherein the coating layer being a material selected from the group consisting of hardfacing including hardfacing applied by a plasma transferred arc process, polycrystalline diamond, diamond, cubic boron nitride, and polycrystalline cubic boron nitride. 
     
     
         7 . The cutting bit according to  claim 1  wherein the slimness ratio ranging between about 0.15 and about 0.25. 
     
     
         8 . The cutting bit according to  claim 1  wherein the slimness ratio ranging between about 0.15 and about 0.19. 
     
     
         9 . The cutting bit according to  claim 1  wherein the superhard insert being selected from the group consisting of a polycrystalline diamond insert, a polycrystalline cubic boron nitride insert, a cubic boron nitride insert, and a superhard coating material-coated insert. 
     
     
         10 . The cutting bit according to  claim 9  wherein the superhard coating includes hardfacing including hardfacing applied by a plasma transferred arc process. 
     
     
         11 . A cutting bit for impinging earth strata, the cutting bit comprising:
 a highly wear-resistant elongate cutting bit body having an axial forward end and an axial rearward end, an enlarged dimension head portion at the axial forward end and a reduced dimension shank portion at the axial rearward end, and at least a part of the highly wear-resistant elongate cutting bit body comprising a hard component-matrix composite material to provide wear resistance, and   a hard insert affixed to the head portion at the axial forward end of the cutting bit body.   
     
     
         12 . The cutting bit according to  claim 11  wherein the highly wear-resistant elongate cutting bit body having a maximum transverse dimension and a longitudinal axial length a slimness ratio comprising the ratio of the maximum transverse dimension to the longitudinal axial length, and the slimness ratio ranging between about 0.15 and about 0.60. 
     
     
         13 . The cutting bit according to  claim 12  wherein the slimness ratio ranging between about 0.15 and about 0.25. 
     
     
         14 . The cutting bit according to  claim 11  wherein the hard component matrix composite material consisting of a plurality of discrete hard constituents and matrix powder of hard particles and an infiltrant alloy bonded together to form the hard component-matrix composite; and
 the infiltrant alloy having a melting point between about 500 degrees Centigrade and about 1400 degrees Centigrade;   the matrix powder comprises one or more of the following: cast carbides, spherical sintered carbides, crushed cemented carbide particles, crushed cast carbide particles, crushed carbide particles, and cemented carbide powder, steel particles, carbonyl iron particles, and coated carbide particles;   the discrete hard constituents comprise one or more of cemented carbides and ceramics; sintered cemented tungsten carbide wherein a binder includes one or more of cobalt, nickel, iron and molybdenum; coated sintered cemented tungsten carbide wherein a binder includes one or more of cobalt, nickel, iron and molybdenum, and the coating comprises one or more of nickel, cobalt, iron and molybdenum; one or more of the carbides, nitrides, and borides of one or more of titanium, niobium, tantalum, hafnium, and zirconium; tungsten carbide; one or more of the coated carbides, coated nitrides, and coated borides of one or more of titanium, niobium, tantalum, hafnium, and zirconium wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; coated tungsten carbide wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; coated silicon carbide wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; coated silicon nitride wherein the coating comprises one or more of nickel, cobalt, iron and molybdenum; and coated boron carbide.   
     
     
         15 . The cutting bit according to  claim 11  wherein the highly wear-resistant elongate cutting bit body having an axial forward portion adjacent the axial forward end thereof, and the highly wear-resistant elongate cutting bit body having an axial rearward portion adjacent the axial rearward end thereof, and the axial forward portion being attached to the axial rearward portion at an interface, and the interface presenting a non-planar surface area. 
     
     
         16 . A cutting bit for impinging earth strata, the cutting bit comprising:
 a highly wear-resistant elongate cutting bit body having an axial forward end and an axial rearward end, an enlarged dimension head portion at the axial forward end and a reduced dimension shank portion at the axial rearward end, and the highly wear-resistant elongate cutting bit body having a maximum transverse dimension and a longitudinal axial length;   the highly wear-resistance cutting bit body comprising a substrate, and at least a part of the substrate having a hardfacing layer thereon;   a hard insert affixed to the head portion at the axial forward end of the cutting bit body; and   a slimness ratio comprising the ratio of the maximum transverse dimension to the longitudinal axial length, and the slimness ratio ranging between about 0.15 and about 0.25.   
     
     
         17 . A cutting bit for impinging earth strata, the cutting bit comprising:
 a highly wear-resistant elongate cutting bit body having an axial forward end and an axial rearward end, an enlarged dimension head portion at the axial forward end and a reduced dimension shank portion at the axial rearward end, and the highly wear-resistant elongate cutting bit body carrying a wear rotator to enhance rotation; and   a hard insert affixed to the head portion at the axial forward end of the cutting bit body.   
     
     
         18 . The cutting bit according to  claim 17  wherein the highly wear-resistant elongate cutting bit body comprising a substrate made of steel, and the steel substrate carrying the wear rotator. 
     
     
         19 . The cutting bit according to  claim 17  wherein the wear rotator being attached to the cutting bit body using an attachment material. 
     
     
         20 . The cutting bit according to  claim 17  wherein the wear rotator being attached to the cutting bit body without an attachment material. 
     
     
         21 . The cutting bit according to  claim 17  wherein the highly wear-resistant elongate cutting bit body being perimeter-weighted, and a plurality of the discrete rotator wear members at the periphery of the head portion. 
     
     
         22 . The cutting bit according to  claim 17  wherein the discrete rotator wear members being made of a material selected from the group consisting of a hard component-matrix composite material, a cemented carbide, and a superhard material. 
     
     
         23 . The cutting bit according to  claim 17  wherein the discrete rotator wear member presenting an exposed rotator surface against which the pieces of the earth strata impinge during the engagement of the cutting bit with the earth strata, and the exposed rotator surface increases with the duration of the engagement of the cutting bit with the earth strata. 
     
     
         24 . The cutting bit according to  claim 17  wherein the head portion having an interior region with a first density and a perimeter region with a second density, and the second density being different from the first density. 
     
     
         25 . The cutting bit according to  claim 17  wherein the highly wear-resistant cutting bit body carrying a plurality of the rotator wear members, and the rotator wear members project the same distance from the head portion. 
     
     
         26 . The cutting bit according to  claim 17  wherein the highly wear-resistant cutting bit body carrying a plurality of the rotator wear members, and the rotator wear members project differing distances from the head portion. 
     
     
         27 . A cutting bit for impinging earth strata, the cutting bit comprising:
 a highly wear-resistant elongate cutting bit body having an axial forward end and an axial rearward end, an enlarged dimension head portion at the axial forward end and a reduced dimension shank portion at the axial rearward end, and the highly wear-resistant elongate cutting bit body having a maximum transverse dimension and a longitudinal axial length;   a hard insert affixed to the head portion at the axial forward end of the cutting bit body; and   a slimness ratio comprising the ratio of the maximum transverse dimension to the longitudinal axial length, and the slimness ratio ranging between about 0.15 and about 0.25.   
     
     
         28 . The cutting bit according to  claim 27  wherein the slimness ratio ranging between about 0.15 and about 0.20.