Earth-boring tools including inertia modifying members and related methods

Abstract

An earth-boring tool includes a tool body including at least one blade and a center longitudinal axis extending through the tool body. The tool body includes a first material exhibiting a first volumetric density. The earth-boring tool includes at least one inertia modifying member, each inertia modifying member disposed at least partially within an inertia modification zone of the tool body. The at least one inertia modifying member includes a second material exhibiting a second volumetric density different than the first density. Related earth-boring tools, adapters, methods, and systems are also disclosed.

1 . An earth-boring tool, comprising:
 a tool body comprising at least one blade and a center longitudinal axis extending through the tool body, wherein the tool body comprises a first material exhibiting a first volumetric density; and   at least one inertia modifying member, each inertia modifying member disposed at least partially within an inertia modification zone of the tool body, the at least one inertia modifying member comprising at least one elongated lateral plug having a length extending along a longitudinal axis, the longitudinal axis extending at least partially into the tool body at an angle relative to the center longitudinal axis, the at least one elongated lateral plug comprising a second material exhibiting a second volumetric density different than the first volumetric density.   
     
     
         2 .- 3 . (canceled) 
     
     
         4 . The earth-boring tool of  claim 1 , wherein the at least one lateral plug comprises more than one lateral plug, each lateral plug at least substantially longitudinally aligned with a respective blade of the least one blade of the tool body. 
     
     
         5 . The earth-boring tool of  claim 1 , wherein the at least one lateral plug extends at least partially into the tool body in a direction at an angle within a range of from about 10° to about 90° with respect to the center longitudinal axis of the tool body. 
     
     
         6 . The earth-boring tool of  claim 1 , wherein the at least one inertia modifying member further comprises at least one inertia plate on the at least one blade. 
     
     
         7 . The earth-boring tool of  claim 6 , wherein the at least one inertia plate at least partially defines one or more cutting edges on a rotationally leading edge of the at least one blade. 
     
     
         8 . The earth-boring tool of  claim 1 , wherein the inertia modification zone exhibits a hollow cylindrical shape defined by a first diameter of the earth-boring tool and a second diameter of the earth-boring tool. 
     
     
         9 . The earth-boring tool of  claim 1 , wherein the at least one inertia modifying member further comprises at least one blade insert, the at least one blade comprising the at least one blade insert. 
     
     
         10 . The earth-boring tool of  claim 1 , wherein the at least one inertia modifying member further comprises a bridge mounted on the at least one blade and at least substantially encircling the tool body. 
     
     
         11 . The earth-boring tool of  claim 1 , wherein the first volumetric density is within a range of from about 1 g/cm 3  to about 25 g/cm 3  and the second volumetric density is within a range of from about 4 g/cm 3  to about 18 g/cm 3 . 
     
     
         12 . The earth-boring tool of  claim 1 , wherein the second material comprises one or more of steel, aluminum, diamond, lead, carbon, graphite, tungsten, titanium, and alloys thereof. 
     
     
         13 . The earth-boring tool of  claim 1 , wherein an absolute value of a difference between the first volumetric density and the second volumetric density is within a range of from about 1 g/cm 3  to about 24 g/cm 3 . 
     
     
         14 . A method of modifying rotational inertia of an earth-boring tool, the earth-boring tool comprising a tool body comprising a first material exhibiting a first volumetric density, the method comprising:
 providing at least one inertia modifying member within an inertia modification zone defined by a first diameter of the earth-boring tool and a second diameter of the earth-boring tool, the at least one inertia modifying member comprising a second material having a second volumetric density which is different than the first volumetric density,   wherein the at least one inertia modifying member comprises one or more lateral plugs having a length extending along a longitudinal axis, the longitudinal axis extending at least partially into the tool body at an angle relative to the center longitudinal axis.   
     
     
         15 . The method of  claim 14 , comprising selecting the at least one inertia modifying member to comprise one or more of steel, aluminum, diamond, lead, carbon, graphite, tungsten, titanium, and alloys thereof. 
     
     
         16 . The method of  claim 14 , comprising selecting the second material to exhibit a volumetric density of greater than or equal to about 8 g/cm 3 . 
     
     
         17 . The method of  claim 14 , wherein the at least one inertia modifying member comprises two or more inertia modifying members. 
     
     
         18 .- 20 . (canceled)