Plate structure for earth-boring tools, tools including plate structures and methods of forming such tools

Abstract

Plate structures attachable to earth-boring tools comprise a disk including a circumferentially extending rim configured for attachment to an earth-boring tool. An aperture is formed through a portion of the disk and positioned radially interior from the rim. The aperture is configured to at least partially align with at least one junk slot of the earth-boring tool. Earth-boring tools comprising such plate structures, and methods of forming such earth-boring tools are also disclosed.

1 . A plate structure attachable to an earth-boring tool, comprising:
 a disk comprising a circumferentially extending rim configured for attachment to an earth-boring tool; and   an aperture through a portion of the disk configured to at least partially circumferentially align with at least one junk slot of an earth-boring tool, the aperture being positioned radially interior from the rim.   
     
     
         2 . The plate structure of  claim 1 , wherein the rim has a chamfered portion thereon. 
     
     
         3 . The plate structure of  claim 1 , wherein the disk comprises a material selected from the group consisting of a metal, a metal alloy, and a particle-matrix composite. 
     
     
         4 . The plate structure of  claim 1 , further comprising at least one of a wear-resistant insert and a wear-resistant coating on at least an outer surface of the rim. 
     
     
         5 . The plate structure of  claim 1 , wherein the aperture comprises a plurality of apertures through a portion of the disk, each aperture of the plurality of apertures configured to at least partially align with at least a portion of at least one junk slot. 
     
     
         6 . The plate structure of  claim 1 , further comprising a plurality of gussets attached to a trailing surface of the disk. 
     
     
         7 . The plate structure of  claim 6  wherein at least the rim and the plurality of gussets comprise a hardfacing material over at least a portion of a surface thereof. 
     
     
         8 . An earth-boring tool, comprising:
 a body comprising a face at a leading end thereof and structure at a trailing end thereof for connecting to a drill string;   a disk encompassing a portion of the structure at the trailing end and comprising a rim extending around an outer circumference thereof and at least one aperture through a surface of the disk and positioned radially inward from the rim.   
     
     
         9 . The earth-boring tool of  claim 8 , wherein the body comprises a longitudinally extending shaft, and further comprising:
 a pilot bit coupled to a leading portion of the longitudinally extending shaft; and   a reamer assembly coupled to the body and trailing the pilot bit.   
     
     
         10 . The earth-boring tool of  claim 9 , wherein the pilot bit is configured as a roller cone bit, a drag bit, or a hybrid bit. 
     
     
         11 . The earth-boring tool of  claim 9 , wherein the reamer assembly comprises a plurality of bit legs coupled to an outer periphery of the body and forming a plurality of junk slots therebetween. 
     
     
         12 . The earth-boring tool of  claim 11 , wherein the disk comprises a plurality of apertures and wherein each aperture of the plurality of apertures is at least partially circumferentially aligned with at least a portion of at least one junk slot of the plurality of junk slots. 
     
     
         13 . The earth-boring tool of  claim 8 , wherein the rim comprises a chamfered portion thereon. 
     
     
         14 . The earth-boring tool of  claim 8 , further comprising at least one of a wear-resistant insert and a wear-resistant coating on at least an outer surface of the rim. 
     
     
         15 . The earth-boring tool of  claim 8 , wherein the disk and the body comprise an integral structure. 
     
     
         16 . The earth-boring tool of  claim 8 , further comprising a plurality of gussets attached to a trailing surface of the disk. 
     
     
         17 . The earth-boring tool of  claim 8 , further comprising a sleeve structure, wherein the plurality of gussets is coupled to the sleeve structure. 
     
     
         18 . A method of forming an earth-boring tool, comprising:
 forming a disk comprising a rim extending around an outer circumference thereof;   forming at least one aperture through a surface of the disk and positioned radially inward from the rim;   forming a body comprising a face at a leading end thereof; and   coupling the disk to the body, wherein a connecting structure protrudes from the body and extends through the disk radially inwardly of the at least one aperture.   
     
     
         19 . The method of  claim 18 , wherein forming at least one of the body and the disk comprises:
 providing a powder mixture;   pressing the powder mixture to form a green powder compact; and   at least partially sintering the green powder compact.   
     
     
         20 . The method of  claim 18 , wherein forming the disk comprises forming the disk integrally and substantially simultaneously with forming the body. 
     
     
         21 . The method of  claim 18 , wherein forming the disk comprises forming the disk separate from the body and coupling the disk to the body. 
     
     
         22 . The method of  claim 18 , further comprising forming a chamfered portion on an outer surface of the rim. 
     
     
         23 . The method of  claim 18 , further comprising disposing at least one of a wear-resistant insert and a wear-resistant coating on at least an outer surface of the rim. 
     
     
         24 . The method of  claim 18 , further comprising:
 forming a plurality of gussets; and   securing the plurality of gussets to the disk.   
     
     
         25 . The method of  claim 24 , further comprising securing the plurality of gussets to a sleeve protruding axially from the disk. 
     
     
         26 . The method of  claim 18 , further comprising forming a plurality of gussets coupled with the disk substantially simultaneously with the formation thereof. 
     
     
         27 . The method of  claim 26 , further comprising forming a sleeve axially protruding from disk and secured to the disk and to the sleeve substantially simultaneously with forming the disk and the plurality of gussets. 
     
     
         28 . The method of  claim 18 , further comprising substantially circumferentially aligning a junk slot associated with the body with the at least one aperture.