Abstract: A cemented tungsten carbide body is formed by mixing a tungsten carbide powder and a cobalt powder together to form a powder mixture. The tungsten carbide powder makes up greater than or equal to 80 weight percent of the powder mixture, while the cobalt binder powder makes up about 1.5 weight percent to about 20 weight percent of the powder mixture. Next, the powder mixture is compacted to form a green compact, and a boron nitride coating is applied to a surface of the green compact to form a coated compact. The coated compact is sintered at a temperature sufficient to melt the cobalt powder, such that boron from the boron nitride coating diffuses into the compact and creates a gradient of metallic cobalt and boron extending inward from the surface. The metallic cobalt content increases from the surface inward, while the boron content decreases from the surface inward.

Abstract: Provided is a corrosion, erosion and wear resistant cemented carbide for high demand applications including, for example, use as a component within oil and gas production. The cemented carbide includes a hard phase and a binder phase. The cemented carbide may include, for example. Ni, Cr and Mo. The binder phase content of the cemented carbide is between 7 to 11 wt %. The WC of the cemented carbide may have an average grain size of from 0.1 to 2 ?m.

Abstract: Provided is a corrosion, erosion and wear resistant cemented carbide for high demand applications including, for example, use as a component within oil and gas production. The cemented carbide includes a hard phase and a binder phase. The cemented carbide may include, for example. Ni, Cr and Mo. The binder phase content of the cemented carbide is between 7 to 11 wt %. The WC of the cemented carbide may have an average grain size of from 0.1 to 2 ?m.

Abstract: A method for repairing a drill bit includes: scanning the drill bit after manufacture thereof; comparing the scan to a design model of the drill bit to recognize one or more features of the drill bit, thereby generating a first model of the as-built drill bit; scanning the drill bit after drilling with the drill bit; comparing the scan of the used drill bit to the first model to recognize the features, thereby generating a second model of the used drill bit; simulating a plurality of repair strategies using the first and second models; and selecting one of the repair strategies by comparing results of the simulations.

Abstract: A bottomhole assembly includes: a drill bit operable to vibrate when engaged with a formation and rotated; and a suspension sub including: a stator barrel for connection to a pipe string; a traveler barrel for connection to the drill bit; a slip joint longitudinally coupling the traveler barrel to the stator barrel while allowing movement of the traveler barrel between an extended position and a retracted position; a torsional joint connecting the traveler barrel to the stator barrel at and between the positions; and one or more springs disposed between the stator barrel and the traveler barrel. The suspension is tuned relative to the drill bit to: dampen the vibration of the drill bit when the BHA is rotated at a first angular velocity; and resonate the vibration of the drill bit when the BHA is rotated at a second angular velocity, thereby imparting percussive energy to the drill bit.

Abstract: A bottomhole assembly includes: a drill bit operable to vibrate when engaged with a formation and rotated; and a suspension sub including: a stator barrel for connection to a pipe string; a traveler barrel for connection to the drill bit; a slip joint longitudinally coupling the traveler barrel to the stator barrel while allowing movement of the traveler barrel between an extended position and a retracted position; a torsional joint connecting the traveler barrel to the stator barrel at and between the positions; and one or more springs disposed between the stator barrel and the traveler barrel. The suspension is tuned relative to the drill bit to: dampen the vibration of the drill bit when the BHA is rotated at a first angular velocity; and resonate the vibration of the drill bit when the BHA is rotated at a second angular velocity, thereby imparting percussive energy to the drill bit.

Abstract: A method for manufacturing a matrix drill bit includes: placing a metallic blank within a casting assembly including a mold having an inner surface formed into a negative shape of facial features of the drill bit; loading powder into an annulus formed between the blank and the mold, the powder including at least one of: ceramic powder and cermet powder; placing a binder alloy into the casting assembly over the blank and the mold; protecting the binder alloy from oxidation; inserting the casting assembly, blank, powder, and binder alloy into a furnace; operating the furnace to heat the protected binder alloy to an infiltration temperature between solidus and liquidus temperatures thereof, thereby infiltrating the powder with the binder alloy and forming a bit body; removing the bit body from the furnace; and after removal, attaching cutters to blades of the bit body.

Abstract: An apparatus and method for manufacturing a downhole tool that reduces failures occurring along a bondline between a cemented matrix coupled around a blank. The cemented matrix material is formed from a tungsten carbide powder, a shoulder powder, and a binder material, wherein at least one of the tungsten carbide powder or the shoulder powder is absent of any free tungsten. The blank, which optionally may be coated, is substantially cylindrically shaped and defines a channel extending from a top portion and through a bottom portion of the blank. The absence of free tungsten from at least one of the tungsten carbide powder or the shoulder powder reduces the reaction with iron from the blank, thereby allowing the control and reduction of intermetallic compounds thickness within the bondline.

Abstract: An apparatus and method for manufacturing a downhole tool that reduces failures occurring along a bondline between a cemented matrix coupled around a blank. The cemented matrix material is formed from a tungsten carbide powder, a shoulder powder, and a binder material, wherein at least one of the tungsten carbide powder or the shoulder powder is absent of any free tungsten. The blank, which optionally may be coated, is substantially cylindrically shaped and defines a channel extending from a top portion and through a bottom portion of the blank. The absence of free tungsten from at least one of the tungsten carbide powder or the shoulder powder reduces the reaction with iron from the blank, thereby allowing the control and reduction of intermetallic compounds thickness within the bondline.